Commit Graph

1105 Commits

Author SHA1 Message Date
Ingo Molnar
87cfeb1920 perf/core fixes and improvements:
kernel + tools/perf:
 
   Alexey Budankov:
 
   - Introduce CAP_PERFMON to kernel and user space.
 
 callchains:
 
   Adrian Hunter:
 
   - Allow using Intel PT to synthesize callchains for regular events.
 
   Kan Liang:
 
   - Stitch LBR records from multiple samples to get deeper backtraces,
     there are caveats, see the csets for details.
 
 perf script:
 
   Andreas Gerstmayr:
 
   - Add flamegraph.py script
 
 BPF:
 
   Jiri Olsa:
 
   - Synthesize bpf_trampoline/dispatcher ksymbol events.
 
 perf stat:
 
   Arnaldo Carvalho de Melo:
 
   - Honour --timeout for forked workloads.
 
   Stephane Eranian:
 
   - Force error in fallback on :k events, to avoid counting nothing when
     the user asks for kernel events but is not allowed to.
 
 perf bench:
 
   Ian Rogers:
 
   - Add event synthesis benchmark.
 
 tools api fs:
 
   Stephane Eranian:
 
  - Make xxx__mountpoint() more scalable
 
 libtraceevent:
 
   He Zhe:
 
   - Handle return value of asprintf.
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQR2GiIUctdOfX2qHhGyPKLppCJ+JwUCXp2LlQAKCRCyPKLppCJ+
 J95oAP0ZihVUhESv/gdeX0IDE5g6Rd2V6LNcRj+jb7gX9NlQkwD/UfS454WV1ftQ
 qTwrkKPzY/5Tm2cLuVE7r7fJ6naDHgU=
 =FHm4
 -----END PGP SIGNATURE-----

Merge tag 'perf-core-for-mingo-5.8-20200420' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull perf/core fixes and improvements from Arnaldo Carvalho de Melo:

kernel + tools/perf:

  Alexey Budankov:

  - Introduce CAP_PERFMON to kernel and user space.

callchains:

  Adrian Hunter:

  - Allow using Intel PT to synthesize callchains for regular events.

  Kan Liang:

  - Stitch LBR records from multiple samples to get deeper backtraces,
    there are caveats, see the csets for details.

perf script:

  Andreas Gerstmayr:

  - Add flamegraph.py script

BPF:

  Jiri Olsa:

  - Synthesize bpf_trampoline/dispatcher ksymbol events.

perf stat:

  Arnaldo Carvalho de Melo:

  - Honour --timeout for forked workloads.

  Stephane Eranian:

  - Force error in fallback on :k events, to avoid counting nothing when
    the user asks for kernel events but is not allowed to.

perf bench:

  Ian Rogers:

  - Add event synthesis benchmark.

tools api fs:

  Stephane Eranian:

 - Make xxx__mountpoint() more scalable

libtraceevent:

  He Zhe:

  - Handle return value of asprintf.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-04-22 14:08:28 +02:00
Mauro Carvalho Chehab
33fc918ab8 media: admin-guide: split driver-specific indexes to new files
In order to better organize the main admin-guide index,
place the driver-specific indexes on separate files.

This ensures a more consistent numbering at the main index.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 08:29:45 +02:00
Mauro Carvalho Chehab
a79a0e71ae media: admin-guide: reorganize the guide
Separate the generic documentation from the driver-specific
parts, and use a better title for the documentation.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 08:29:23 +02:00
Mauro Carvalho Chehab
f45ce7a1e5 media: admin-guide: bt8xx.rst: fix a broken cross-reference
The old cards.rst file doesn't exist anymore. Also, it is not
the right reference there, as it should be pointing to the
bttv-specific cardlist.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 08:29:01 +02:00
Mauro Carvalho Chehab
8cf8f0a68a media: admin-guide: add test-drivers
While test drivers is probably something that normal users
won't bother, it doesn't hurt to add them to the card list.

This way, all drivers, except for the ones under staging,
would be listed there.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 08:28:46 +02:00
Mauro Carvalho Chehab
c84315dd8a media: admin-guide: add card lists for radio and firewire
Document the supported radio devices, plus document the
firewire driver.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 08:28:31 +02:00
Mauro Carvalho Chehab
a70559d37a media: admin-guide: add SPI cards to platform drivers
The SPI cards are also under the concept of "platform" drivers
as defined at the section introduction.

So, add a SPI card list there.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 08:28:15 +02:00
Mauro Carvalho Chehab
c127fa9d3d media: admin-guide: add a list of I2C drivers
For completeness, let's add a list of I2C drivers.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 08:28:00 +02:00
Mauro Carvalho Chehab
9436af9eb4 media: admin-guide: add a list of platform drivers
There's no reason why to keep platform drivers out of the
card list. Add them.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 08:27:42 +02:00
Mauro Carvalho Chehab
0753351432 media: admin-guide: add a table with USB drivers
Having a table with a list of all USB drivers seems worth,
and it comes almost for free, as we can just use Kconfig
descriptions (with some adjustments).

So, add a table for that.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 08:27:24 +02:00
Mauro Carvalho Chehab
0cb8f667ec media: admin-guide: add a list of media PCI cards
Instead of listing "other" PCI card list, just add a list with
the existing drivers (not including sub-drivers).

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 08:27:05 +02:00
Mauro Carvalho Chehab
97b202b004 media: admin-guide: replace the frontend drivers list
The frontend drivers list is incomplete. Update it from
what's there at the Kernel Kconfig files.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 08:26:38 +02:00
Mauro Carvalho Chehab
d3cb083207 media: admin-guide: split DVB cards.rst
The DVB cards.rst file is old and outdated. It also contains
data that are contained on other cardlists. Remove the
duplicated information and split frontends and PCI cards on
separate files.

As all USB cards already have their own card lists, just drop
the old USB data there.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 08:26:12 +02:00
Mauro Carvalho Chehab
ea90626fdf media: admin-guide: add a cardlist for all other USB cards
There are several other USB cards. Most of them support just
one device. The only exception is the "pwc" driver. But, as
updates to it are not frequent, let's just place everything
manually into a single file.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 08:25:39 +02:00
Mauro Carvalho Chehab
da95d30bb0 media: admin-guide: add a card list for the Siano driver
The siano driver looks like em28xx, except that its cards
are split on 3 drivers.

Add a card list for it.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 08:25:14 +02:00
Mauro Carvalho Chehab
4b45a0cd39 media: admin-guide: add support for the remaining dvb-usb boards
Add documentation for the remaining dvb-usb boards.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 08:24:38 +02:00
Mauro Carvalho Chehab
f21067392b media: admin-guide: add dibusb-mb and dibusb-mc card lists
Document the supported dib0300 boards.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 08:24:04 +02:00
Mauro Carvalho Chehab
9f054a7e7d media: admin-guide: add cardlist for dib0700 driver
Document the cards supported by dib0700 driver.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 08:23:01 +02:00
Mauro Carvalho Chehab
760ec48b6b media: admin-guide: add dvb-usb-v2 card lists
Include cardlist documentation for the sub-drivers supported by
dvb-usb-v2 core.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 08:22:37 +02:00
Mauro Carvalho Chehab
17ce5e6d72 media: admin-guide: improve cardlist.rst documentation
The cardlist section is important for some boards, because they
may require extra modprobe parameters.

Improve the docs to mention that.

Thanks-to: Hans Verkuil <hverkuil-cisco@xs4all.nl> # for providing me some PCI IDs
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 08:19:01 +02:00
Mauro Carvalho Chehab
2aca74c8b1 media: admin-guide: add a generic building guide
Several of the existing documents under the media admin-guide
contain build procedures.

Add an specific chapter describing it. This document was
partially inspired on the modifications I made to the bttv.rst
file.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 07:48:36 +02:00
Mauro Carvalho Chehab
d9d43617bb media: admin-guide: Add an introduction chapter
The media's admin guide is currently just a group of
not-connected docs.

Add an introduction chapter for it to start making sense
to a random reader.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 07:47:53 +02:00
Mauro Carvalho Chehab
433c8e5660 media: admin-guide: update em28xx cardlist
A new em28xx card was added upstream. Update cards list
accordingly.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 07:45:44 +02:00
Mauro Carvalho Chehab
74da0d515c media: admin-guide: add a card list for cx231xx boards
It is interesting to have a card list also for cx231xx
driver, as it currently supports 27 different boards.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-22 07:45:28 +02:00
Fabio Estevam
d00c9761af media: imx.rst: Provide streaming examples for imx6q-sabresd
Improve the documentation by providing examples on how to test camera
capture on imx6q-sabresd via v4l2-ctl and Gstreamer.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Steve Longerbeam<slongerbeam@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-21 13:30:32 +02:00
Fabio Estevam
8a4676d6e6 media: imx.rst: Provide the OV560 module part number
In order to improve the documentation, provide the OV5640 MIPI module
part number that is used on the imx6q-sabresd board.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-21 13:29:34 +02:00
Fabio Estevam
62ce7201f4 media: imx.rst: Provide an example for unprocessed video capture
The current example for imx6q-sabresd is for a direct conversion pipeline.

Provide an extra example using unprocessed video capture for completeness.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-21 13:29:11 +02:00
Fabio Estevam
9429e7072f media: imx.rst: Fix the MIPI CSI-2 virtual channel
The current instructions for imx6q-sabresd do not lead to functional
capture on OV5640 MIPI CSI-2.

The reason for this, as explained by Steve Longerbeam, is that OV5640 by
default transmits on virtual channel 0, not channel 1 as is given in the
instructions.

Adapt the instructions to use virtual channel 0 so that a working
camera setup can be achieved on imx6q-sabresd.

Also, since we are using an IC direct conversion pipeline, improve
the example by demonstrating colorspace and scaling.

Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Steve Longerbeam<slongerbeam@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-21 13:28:43 +02:00
Cristian Souza
7dbffd3f84 docs: admin-guide: Clarify sentences
Changes to make the text more formal and organized. The reasons are now cited and described at the same time.
Minor grammatical problems have also been fixed.

Signed-off-by: Cristian Souza <cristianmsbr@gmail.com>
Link: https://lore.kernel.org/r/20200411010201.GA22706@darkstar
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-20 17:03:42 -06:00
Stephen Kitt
5d8e5aee0e docs: sysctl/kernel: document BPF entries
Based on the implementation in kernel/bpf/syscall.c,
kernel/bpf/trampoline.c, include/linux/filter.h, and the documentation
in bpftool-prog.rst.

Signed-off-by: Stephen Kitt <steve@sk2.org>
Link: https://lore.kernel.org/r/20200315122648.20558-1-steve@sk2.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-20 16:59:23 -06:00
Mauro Carvalho Chehab
4a3fe6541c docs: mm: userfaultfd.rst: use a cross-reference for a section
Instead of using "foo", let's use `foo`_, with is a ReST way of
saying that foo is a section of the document. With that, after
building the docs, an hyperlink is generated.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/f46b45f1aaec233217f2e0b0438bbd8cc16fe17b.1586881715.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-20 15:45:23 -06:00
Mauro Carvalho Chehab
14a7e51ff1 docs: mm: userfaultfd.rst: use `foo` for literals
Several parts of this document define literals: ioctl names,
function calls, directory patches, etc. Mark those as literal
blocks, in order to improve its readability (both at text mode
and after parsed by Sphinx.

This fixes those two warnings:

	Documentation/admin-guide/mm/userfaultfd.rst:139: WARNING: Inline emphasis start-string without end-string.
	Documentation/admin-guide/mm/userfaultfd.rst:139: WARNING: Inline emphasis start-string without end-string.

produced during documentation build.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/2ae061761baf8fe00cdf8a7e6dae293756849a05.1586881715.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-20 15:45:23 -06:00
Mauro Carvalho Chehab
00aff95659 docs: ras: don't need to repeat twice the same thing
We don't need to say twice "for the first time" at the same
paragraph.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/f76dcae96de8b1bb8ee37a79781c111c825e26d6.1586881715.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-20 15:45:23 -06:00
Mauro Carvalho Chehab
cfa204984d docs: ras: get rid of some warnings
Sphinx produce some warnings due to a bad table format:

    Documentation/admin-guide/ras.rst:358: WARNING: Definition list ends without a blank line; unexpected unindent.
    Documentation/admin-guide/ras.rst:358: WARNING: Definition list ends without a blank line; unexpected unindent.
    Documentation/admin-guide/ras.rst:363: WARNING: Definition list ends without a blank line; unexpected unindent.
    Documentation/admin-guide/ras.rst:363: WARNING: Definition list ends without a blank line; unexpected unindent.

Rearrange the things there in order to supress the warnings
while being precise at the Sphinx output about how ranks are
mapped into csrows.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/9e1bb44d6dbedb5b6f049d081b47da1f9620de16.1586881715.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-20 15:45:23 -06:00
Mauro Carvalho Chehab
0c1bc6b845 docs: filesystems: fix renamed references
Some filesystem references got broken by a previous patch
series I submitted. Address those.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: David Sterba <dsterba@suse.com> # fs/affs/Kconfig
Link: https://lore.kernel.org/r/57318c53008dbda7f6f4a5a9e5787f4d37e8565a.1586881715.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-20 15:45:22 -06:00
Mauro Carvalho Chehab
9e04ff70cf Linux 5.7-rc2
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAl6cxDAeHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGb2YH/3V3yrWOgbZkEWvO
 IwW5nSjYk+xTBs7Tf5+nycWHpr+e92tX4m/+DZ6qn1sQpjdKEA7EZ/E0mpm0fm5w
 Po+dzy4PP40CLi/Z0mXl3U3FWmp5l50Q4tEs5fzI6rQPKjX+G5qO8+J7Yu1iNduJ
 KRbNeKCnUGHf2mRYiOJRNurVm4Yv370AIyvulxX5FkZHN7hTq/Js76sRV1BSnG7k
 o1Vs4vvFSSdFgVxyuflpV0Uv9bDTxppqiwQ4ktntB8TKmVtXLT25wcO4V5LwRjQt
 6o064j343Q+OQ4t/LZVKYUB0Fmw8Ks1YH00OOdH6G41wY6LogaxYIXM1YvUZ4NwQ
 HjNsASY=
 =kvEN
 -----END PGP SIGNATURE-----

Merge tag 'v5.7-rc2' into patchwork

Linux 5.7-rc2

* tag 'v5.7-rc2': (331 commits)
  Linux 5.7-rc2
  mm: Fix MREMAP_DONTUNMAP accounting on VMA merge
  xattr.h: Replace zero-length array with flexible-array member
  uapi: linux: fiemap.h: Replace zero-length array with flexible-array member
  uapi: linux: dlm_device.h: Replace zero-length array with flexible-array member
  tpm_eventlog.h: Replace zero-length array with flexible-array member
  ti_wilink_st.h: Replace zero-length array with flexible-array member
  swap.h: Replace zero-length array with flexible-array member
  skbuff.h: Replace zero-length array with flexible-array member
  sched: topology.h: Replace zero-length array with flexible-array member
  rslib.h: Replace zero-length array with flexible-array member
  rio.h: Replace zero-length array with flexible-array member
  posix_acl.h: Replace zero-length array with flexible-array member
  platform_data: wilco-ec.h: Replace zero-length array with flexible-array member
  memcontrol.h: Replace zero-length array with flexible-array member
  list_lru.h: Replace zero-length array with flexible-array member
  lib: cpu_rmap: Replace zero-length array with flexible-array member
  irq.h: Replace zero-length array with flexible-array member
  ihex.h: Replace zero-length array with flexible-array member
  igmp.h: Replace zero-length array with flexible-array member
  ...
2020-04-20 16:50:25 +02:00
Mark Gross
7222a1b5b8 x86/speculation: Add SRBDS vulnerability and mitigation documentation
Add documentation for the SRBDS vulnerability and its mitigation.

 [ bp: Massage.
   jpoimboe: sysfs table strings. ]

Signed-off-by: Mark Gross <mgross@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
2020-04-20 12:19:22 +02:00
Mark Gross
7e5b3c267d x86/speculation: Add Special Register Buffer Data Sampling (SRBDS) mitigation
SRBDS is an MDS-like speculative side channel that can leak bits from the
random number generator (RNG) across cores and threads. New microcode
serializes the processor access during the execution of RDRAND and
RDSEED. This ensures that the shared buffer is overwritten before it is
released for reuse.

While it is present on all affected CPU models, the microcode mitigation
is not needed on models that enumerate ARCH_CAPABILITIES[MDS_NO] in the
cases where TSX is not supported or has been disabled with TSX_CTRL.

The mitigation is activated by default on affected processors and it
increases latency for RDRAND and RDSEED instructions. Among other
effects this will reduce throughput from /dev/urandom.

* Enable administrator to configure the mitigation off when desired using
  either mitigations=off or srbds=off.

* Export vulnerability status via sysfs

* Rename file-scoped macros to apply for non-whitelist table initializations.

 [ bp: Massage,
   - s/VULNBL_INTEL_STEPPING/VULNBL_INTEL_STEPPINGS/g,
   - do not read arch cap MSR a second time in tsx_fused_off() - just pass it in,
   - flip check in cpu_set_bug_bits() to save an indentation level,
   - reflow comments.
   jpoimboe: s/Mitigated/Mitigation/ in user-visible strings
   tglx: Dropped the fused off magic for now
 ]

Signed-off-by: Mark Gross <mgross@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Tested-by: Neelima Krishnan <neelima.krishnan@intel.com>
2020-04-20 12:19:22 +02:00
Rafael J. Wysocki
33aa46f252 cpufreq: intel_pstate: Use passive mode by default without HWP
After recent changes allowing scale-invariant utilization to be
used on x86, the schedutil governor on top of intel_pstate in the
passive mode should be on par with (or better than) the active mode
"powersave" algorithm of intel_pstate on systems in which
hardware-managed P-states (HWP) are not used, so it should not be
necessary to use the internal scaling algorithm in those cases.

Accordingly, modify intel_pstate to start in the passive mode by
default if the processor at hand does not support HWP of if the driver
is requested to avoid using HWP through the kernel command line.

Among other things, that will allow utilization clamps and the
support for RT/DL tasks in the schedutil governor to be utilized on
systems in which intel_pstate is used.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-04-17 17:04:38 +02:00
Alexey Budankov
025b16f81d doc/admin-guide: update kernel.rst with CAP_PERFMON information
Update the kernel.rst documentation file with the information related to
usage of CAP_PERFMON capability to secure performance monitoring and
observability operations in system.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/84c32383-14a2-fa35-16b6-f9e59bd37240@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:12 -03:00
Alexey Budankov
902a8dcc5b doc/admin-guide: Update perf-security.rst with CAP_PERFMON information
Update perf-security.rst documentation file with the information
related to usage of CAP_PERFMON capability to secure performance
monitoring and observability operations in system.

Committer notes:

While testing 'perf top' under cap_perfmon I noticed that it needs
some more capability and Alexey pointed out cap_ipc_lock, as needed by
this kernel chunk:

  kernel/events/core.c: 6101
       if ((locked > lock_limit) && perf_is_paranoid() &&
               !capable(CAP_IPC_LOCK)) {
               ret = -EPERM;
               goto unlock;
       }

So I added it to the documentation, and also mentioned that if the
libcap version doesn't yet supports 'cap_perfmon', its numeric value can
be used instead, i.e. if:

	# setcap "cap_perfmon,cap_ipc_lock,cap_sys_ptrace,cap_syslog=ep" perf

Fails, try:

	# setcap "38,cap_ipc_lock,cap_sys_ptrace,cap_syslog=ep" perf

I also added a paragraph stating that using an unpatched libcap will
fail the check for CAP_PERFMON, as it checks the cap number against a
maximum to see if it is valid, which makes it use as the default the
'cycles:u' event, even tho a cap_perfmon capable perf binary can get
kernel samples, to workaround that just use, e.g.:

  # perf top -e cycles
  # perf record -e cycles

And it will sample kernel and user modes.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/17278551-9399-9ebe-d665-8827016a217d@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:10 -03:00
Eric Biggers
52338dfb3c docs: admin-guide: merge sections for the kernel.modprobe sysctl
Documentation for the kernel.modprobe sysctl was added both by
commit 0317c5371e ("docs: merge debugging-modules.txt into
sysctl/kernel.rst") and by commit 6e71582506 ("docs: admin-guide:
document the kernel.modprobe sysctl"), resulting in the same sysctl
being documented in two places.  Merge these into one place.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Stephen Kitt <steve@sk2.org>
Link: https://lore.kernel.org/r/20200414172430.230293-1-ebiggers@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-15 14:50:09 -06:00
Mauro Carvalho Chehab
63735af86d media: docs: add cros-references to the other media guides
In order to make easier for people to navigate between the
three media guides, add cross-references between them

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-15 15:51:24 +02:00
Mauro Carvalho Chehab
cc5d250e5a media: docs: move copyrights to the end and update them
The copyright info is not the most valuable information
there. Move them to the end.

While here, change the copyright to cover up to this
year (2020).

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-15 15:51:24 +02:00
Mauro Carvalho Chehab
1c9eeba232 media: docs: get rid of obsoleted udev documentation
This file is very old, and doesn't match the current udev
behavior.

I wanted to preserve it, because we'll need some udev
description some day about how to keep names unique,
but there's nothing here to help with that...

So, be it: let's just discard this document, as it doesn't
provide anything useful anymore.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-15 15:51:23 +02:00
Mauro Carvalho Chehab
08256f12ac media: docs: zr364xx: update documentation
There aren't much to be done here... almost everything is
still valid. The supported boards even reflect the current
driver's state. Yet, some things changed, so let's keep
this document updated.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-15 15:51:23 +02:00
Mauro Carvalho Chehab
12bcf90c69 media: docs: saa7134.rst: update the documentation
There are several things here that are outdated, because this
document was written a long time ago.

Update them to reflect the current status of the driver and
the media subsystem.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-15 15:51:23 +02:00
Mauro Carvalho Chehab
8a1bfbc70d media: docs: update Digital TV faq.rst
This file contains lots of obsoleted information. Update it
to reflect the current status and tools used by Digital TV
users and add pointers to the current locations and to
LinuxTV wiki pages.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-15 15:51:23 +02:00
Mauro Carvalho Chehab
fe877259d8 media: docs: cpia2.rst: do some cleanups
Do some cleanups at the document in order to mark two
literal blocks as such.

While here, simplify two block markups, using the less
verbose option (::).

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-15 15:51:23 +02:00
Mauro Carvalho Chehab
9fafef5857 media: docs: add a cardlist for cx18 boards
There aren't many boards supported by this driver. So, add
a list for it manually generated.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-15 15:51:23 +02:00
Mauro Carvalho Chehab
729126e4b4 media: docs: update bttv.rst information
This document is... old. The bttv driver was one of the first
drivers at the Kernel. So, the document became a little obsoleted.

Update it to reflect some changes that happened along the time
affecting this driver and the subsystem.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-15 15:51:23 +02:00
Mauro Carvalho Chehab
f631516f6d media: docs: bt8xx.rst: update document info
This document is very outdated, and doesn't match the
upstream current way.

Update it, making some parts a little bit more generic.
While the main focus of this document is digital TV
cards, its content also may also help someone with just
analog TV support.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-15 15:51:23 +02:00
Mauro Carvalho Chehab
c5b352431f media: docs: update avermedia.rst contents
While this is old, now that we moved the intro part of it,
its contents seem to be valid, if we mention that we're
talking only about the BT878 support.

Update the document title accordingly and remove the obsolete
note from it.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-15 15:51:23 +02:00
Mauro Carvalho Chehab
03693a5a23 media: docs: intro.rst actually contain DVB references
This document doesn't describe the DVB subsystem. Instead, it
just contain references to some places.

Better name it and improve its contents.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-15 15:51:23 +02:00
Mauro Carvalho Chehab
109895a152 media: docs: dvb_intro.rst: update its contents
The content there is somewhat outdated. Update to reflect
the current status.

While here, remove extra spaces, as we won't be preserving
left margin alinment on this document.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-15 15:51:23 +02:00
Mauro Carvalho Chehab
c4b89166d2 media: docs: split avermedia.rst contents on two files
Part of this document has nothing to do with the Avermedia
driver. It is generic to the entire subsystem. So, split it
on a separate file.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-15 15:51:23 +02:00
Mauro Carvalho Chehab
b533cad6fd media: docs: update cardlists
There were some changes at the drivers adding support for
more cards. Update cardlists accordingly.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-15 15:51:22 +02:00
Milan Broz
0a2bd55c19 dm integrity: document allow_discard option
Add decription of the allow_discard option added in commit
84597a44a9.

Signed-off-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-04-14 13:54:07 -04:00
Bingbu Cao
9611ba28d8 media: ipu3.rst: add yuv-downscaling into pipeline diagram
For ipu3 ImgU image processing, the frame data from TNR can feed into
DDR by Output Formatting System or feed into YUV downscaler to do YUV
downscaling for secondary output, which is usually used for display.
current ImgU image pipeline diagram misses the YUV downscaling,
this patch add it to aligh with actual hardware blocks.

Signed-off-by: Bingbu Cao <bingbu.cao@intel.com>
Suggested-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-14 12:31:55 +02:00
Bingbu Cao
ce7d96a4a7 media: doc-rst: add yavta test example in ipu3 docs
This patch add yavta test command in ipu3.rst as an example on how to
run simple ImgU test using yavta.

Signed-off-by: Bingbu Cao <bingbu.cao@intel.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-14 12:20:37 +02:00
Steve Longerbeam
cdb82f826e media: imx.rst: Add example media graphs
Add the media graph topologies for the i.MX6Q SabreSD and SabreAuto.
This makes it easier to understand the topology and follow the
entity descriptions in the following sections.

Also clarify that the SabreSD and SabreLite media pipeline config examples
are for the i.MX6Q boards.

Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-14 11:35:49 +02:00
Mauro Carvalho Chehab
32e2eae23f media: docs: move user-facing docs to the admin guide
Most of the driver-specific documentation is meant to help
users of the media subsystem.

Move them to the admin-guide.

It should be noticed, however, that several of those files
are outdated and will require further work in order to make
them useful again.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-04-14 10:34:58 +02:00
Linus Torvalds
0785249f8b Time(keeping) updates:
- Fix the time_for_children symlink in /proc/$PID/ so it properly reflects
    that it part of the 'time' namespace
 
  - Add the missing userns limit for the allowed number of time namespaces,
    which was half defined but the actual array member was not added.  This
    went unnoticed as the array has an exessive empty member at the end but
    introduced a user visible regression as the output was corrupted.
 
  - Prevent further silent ucount corruption by adding a BUILD_BUG_ON() to
    catch half updated data.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl6TFe4THHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYob4PD/47Qwz2z2mEeO037VbbI2gY4yl/raFo
 5KPWmnwonKrtVaYAldLutA3iaG7bBbUX5fRvbSRNTS6CJIHwwfLSx7/CeWMmIXEX
 0zsBsn5QXjG89lJZXM+ot74yzjvkeoad2g0jEHv92v0WDSXFiAWhkBUwknfNFbpa
 csEjkdpyn2zTVBGBzKVHWHXddkY0o0Q0JOy0EiH09rHGpQktPoLJdYp73VCygoJd
 NRAXhTmBQq85RMcSB3eVTbSPpIuBUzZke9zoio7YZwEjl6bkvSqetPmTdIr57u4s
 ex3PX++64EXD7r8ZW36fPGDqu6v0CH2ILK7QVhwyHAYJo2LQKVd+v25muaFrzfpn
 dSG1SqabWqdIHUoW/76ORyecAFLTzGwDu07UH+6VJbXeLfmuhe/LI3hdDQFph9NQ
 BOBKhaHm8aXmAmvrkxbbAikSkJYVHrAIp5abI4PSYoPaqK1DWnSPaT1cqtaIUgYL
 Mk15z19V9np4lMCH2cucAlap8U9EvQEIfCRRdl+crDu17ZzGID1pwhY2DA8adqcT
 SUfwzzUaykd5TZtDeIe+6G9fsgf/wbSTSSbrNGKlLXDbxx+iNVXErkmx0JXLEHV4
 47cmBwQZ255DzjMfuS4HzCck2MaaP8mDWgcbszgkP+GFnkf9EAP5XNp9st937mbG
 rzP+NkjNCldN9w==
 =wOiC
 -----END PGP SIGNATURE-----

Merge tag 'timers-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull time(keeping) updates from Thomas Gleixner:

 - Fix the time_for_children symlink in /proc/$PID/ so it properly
   reflects that it part of the 'time' namespace

 - Add the missing userns limit for the allowed number of time
   namespaces, which was half defined but the actual array member was
   not added. This went unnoticed as the array has an exessive empty
   member at the end but introduced a user visible regression as the
   output was corrupted.

 - Prevent further silent ucount corruption by adding a BUILD_BUG_ON()
   to catch half updated data.

* tag 'timers-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ucount: Make sure ucounts in /proc/sys/user don't regress again
  time/namespace: Add max_time_namespaces ucount
  time/namespace: Fix time_for_children symlink
2020-04-12 10:13:14 -07:00
Linus Torvalds
5b8b9d0c6d Merge branch 'akpm' (patches from Andrew)
Merge yet more updates from Andrew Morton:

 - Almost all of the rest of MM (memcg, slab-generic, slab, pagealloc,
   gup, hugetlb, pagemap, memremap)

 - Various other things (hfs, ocfs2, kmod, misc, seqfile)

* akpm: (34 commits)
  ipc/util.c: sysvipc_find_ipc() should increase position index
  kernel/gcov/fs.c: gcov_seq_next() should increase position index
  fs/seq_file.c: seq_read(): add info message about buggy .next functions
  drivers/dma/tegra20-apb-dma.c: fix platform_get_irq.cocci warnings
  change email address for Pali Rohár
  selftests: kmod: test disabling module autoloading
  selftests: kmod: fix handling test numbers above 9
  docs: admin-guide: document the kernel.modprobe sysctl
  fs/filesystems.c: downgrade user-reachable WARN_ONCE() to pr_warn_once()
  kmod: make request_module() return an error when autoloading is disabled
  mm/memremap: set caching mode for PCI P2PDMA memory to WC
  mm/memory_hotplug: add pgprot_t to mhp_params
  powerpc/mm: thread pgprot_t through create_section_mapping()
  x86/mm: introduce __set_memory_prot()
  x86/mm: thread pgprot_t through init_memory_mapping()
  mm/memory_hotplug: rename mhp_restrictions to mhp_params
  mm/memory_hotplug: drop the flags field from struct mhp_restrictions
  mm/special: create generic fallbacks for pte_special() and pte_mkspecial()
  mm/vma: introduce VM_ACCESS_FLAGS
  mm/vma: define a default value for VM_DATA_DEFAULT_FLAGS
  ...
2020-04-10 17:57:48 -07:00
Linus Torvalds
ca6151a978 A handful of late-arriving fixes for the documentation tree.
-----BEGIN PGP SIGNATURE-----
 
 iQFDBAABCAAtFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAl6QnP0PHGNvcmJldEBs
 d24ubmV0AAoJEBdDWhNsDH5Yf2kH+gO2r5g/OzT32Szm3ZgRYgnJ3u6ON6MXllCd
 pxY+M3Yw/3Q4W1CMkg4Oo8Hq97dTSNtPriDpWMBDj6+QvBF1DzG797ThiHHNpTEy
 i0CV5uawvRuWHTr/jOdRZDRosegbTdgqRbj8MWBw9JjWalHky5QUG0StubXy0TPD
 ahj+QRN3oxFqlHr4OtVL8NXTeVwjiXPiRFDrcy/eEw2jb2hkiLhWfElFsh7KhE9L
 K0PPLGKJMqSM6PYjqQqJx+M363Pm/nNpyw5z55pTMn0l5kbG5tu6CIYMlMJmzYBE
 8vwJnxpiA3QRrqG5TtgVLS+yFRxO1AXdY/F6N5qt2hiczUyXlf8=
 =C8i4
 -----END PGP SIGNATURE-----

Merge tag 'docs-5.7-2' of git://git.lwn.net/linux

Pull Documentation fixes from Jonathan Corbet:
 "A handful of late-arriving fixes for the documentation tree"

* tag 'docs-5.7-2' of git://git.lwn.net/linux:
  Documentation: android: binderfs: add 'stats' mount option
  Documentation: driver-api/usb/writing_usb_driver.rst Updates documentation links
  docs: driver-api: address duplicate label warning
  Documentation: sysrq: fix RST formatting
  docs: kernel-parameters.txt: Fix broken references
  docs: kernel-parameters.txt: Remove nompx
  docs: filesystems: fix typo in qnx6.rst
2020-04-10 17:53:43 -07:00
Eric Biggers
6e71582506 docs: admin-guide: document the kernel.modprobe sysctl
Document the kernel.modprobe sysctl in the same place that all the other
kernel.* sysctls are documented.  Make sure to mention how to use this
sysctl to completely disable module autoloading, and how this sysctl
relates to CONFIG_STATIC_USERMODEHELPER.

[ebiggers@google.com: v5]
  Link: http://lkml.kernel.org/r/20200318230515.171692-4-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jeff Vander Stoep <jeffv@google.com>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: NeilBrown <neilb@suse.com>
Link: http://lkml.kernel.org/r/20200312202552.241885-4-ebiggers@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10 15:36:22 -07:00
Roman Gushchin
cf11e85fc0 mm: hugetlb: optionally allocate gigantic hugepages using cma
Commit 944d9fec8d ("hugetlb: add support for gigantic page allocation
at runtime") has added the run-time allocation of gigantic pages.

However it actually works only at early stages of the system loading,
when the majority of memory is free.  After some time the memory gets
fragmented by non-movable pages, so the chances to find a contiguous 1GB
block are getting close to zero.  Even dropping caches manually doesn't
help a lot.

At large scale rebooting servers in order to allocate gigantic hugepages
is quite expensive and complex.  At the same time keeping some constant
percentage of memory in reserved hugepages even if the workload isn't
using it is a big waste: not all workloads can benefit from using 1 GB
pages.

The following solution can solve the problem:
1) On boot time a dedicated cma area* is reserved. The size is passed
   as a kernel argument.
2) Run-time allocations of gigantic hugepages are performed using the
   cma allocator and the dedicated cma area

In this case gigantic hugepages can be allocated successfully with a
high probability, however the memory isn't completely wasted if nobody
is using 1GB hugepages: it can be used for pagecache, anon memory, THPs,
etc.

* On a multi-node machine a per-node cma area is allocated on each node.
  Following gigantic hugetlb allocation are using the first available
  numa node if the mask isn't specified by a user.

Usage:
1) configure the kernel to allocate a cma area for hugetlb allocations:
   pass hugetlb_cma=10G as a kernel argument

2) allocate hugetlb pages as usual, e.g.
   echo 10 > /sys/kernel/mm/hugepages/hugepages-1048576kB/nr_hugepages

If the option isn't enabled or the allocation of the cma area failed,
the current behavior of the system is preserved.

x86 and arm-64 are covered by this patch, other architectures can be
trivially added later.

The patch contains clean-ups and fixes proposed and implemented by Aslan
Bakirov and Randy Dunlap.  It also contains ideas and suggestions
proposed by Rik van Riel, Michal Hocko and Mike Kravetz.  Thanks!

Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Andreas Schaufler <andreas.schaufler@gmx.de>
Acked-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Michal Hocko <mhocko@kernel.org>
Cc: Aslan Bakirov <aslan@fb.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Link: http://lkml.kernel.org/r/20200407163840.92263-3-guro@fb.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10 15:36:21 -07:00
Randy Dunlap
befacdcf47 Documentation: android: binderfs: add 'stats' mount option
Add documentation of the binderfs 'stats' mount option.

Description taken from the commit message.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/baa0aa81-007d-af46-16a5-91fead0bd1b9@infradead.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-10 10:14:53 -06:00
Alyssa Ross
8699039042 Documentation: sysrq: fix RST formatting
"On x86" and "On SPARC" are now definition list terms, like
"On PowerPC", "On other", and "On all".

The Credits list is now a bulleted list, like lots of Credits lists in
other files.  This prevents the list from becoming a single long,
unpunctuated sentence in the generated documentation.

I also did a couple of other tiny readability improvements to the
"How do I use the magic SysRq key?" section while I was there.

Signed-off-by: Alyssa Ross <hi@alyssa.is>
Link: https://lore.kernel.org/r/20200403170701.10852-1-hi@alyssa.is
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-07 13:32:15 -06:00
Jimmy Assarsson
cd4ca34153 docs: kernel-parameters.txt: Fix broken references
Fix remaining broken references in kernel-parameters.txt.

Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Jimmy Assarsson <jimmyassarsson@gmail.com>
Link: https://lore.kernel.org/r/20200402172614.3020-2-jimmyassarsson@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-07 13:29:35 -06:00
Jimmy Assarsson
ed01b03018 docs: kernel-parameters.txt: Remove nompx
x86/mpx was removed in commit 45fc24e89b
("x86/mpx: remove MPX from arch/x86"), this removes the documentation of
parameter nompx.

Fixes: 45fc24e89b ("x86/mpx: remove MPX from arch/x86")
Signed-off-by: Jimmy Assarsson <jimmyassarsson@gmail.com>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/r/20200402172614.3020-1-jimmyassarsson@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-04-07 13:28:56 -06:00
Baoquan He
f3cd4c865b mm/memory_hotplug.c: only respect mem= parameter during boot stage
In commit 357b4da50a ("x86: respect memory size limiting via mem=
parameter") a global varialbe max_mem_size is added to store the value
parsed from 'mem= ', then checked when memory region is added.  This truly
stops those DIMMs from being added into system memory during boot-time.

However, it also limits the later memory hotplug functionality.  Any DIMM
can't be hotplugged any more if its region is beyond the max_mem_size.  We
will get errors like:

[  216.387164] acpi PNP0C80:02: add_memory failed
[  216.389301] acpi PNP0C80:02: acpi_memory_enable_device() error
[  216.392187] acpi PNP0C80:02: Enumeration failure

This will cause issue in a known use case where 'mem=' is added to the
hypervisor.  The memory that lies after 'mem=' boundary will be assigned
to KVM guests.  After commit 357b4da50a merged, memory can't be extended
dynamically if system memory on hypervisor is not sufficient.

So fix it by also checking if it's during boot-time restricting to add
memory.  Otherwise, skip the restriction.

And also add this use case to document of 'mem=' kernel parameter.

Fixes: 357b4da50a ("x86: respect memory size limiting via mem= parameter")
Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Link: http://lkml.kernel.org/r/20200204050643.20925-1-bhe@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:40 -07:00
Martin Cracauer
57e5d4f278 userfaultfd: wp: UFFDIO_REGISTER_MODE_WP documentation update
Add documentation about the write protection support.

[peterx@redhat.com: rewrite in rst format; fixups here and there]
Signed-off-by: Martin Cracauer <cracauer@cons.org>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Reviewed-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Denis Plotnikov <dplotnikov@virtuozzo.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Marty McFadden <mcfadden8@llnl.gov>
Cc: Maya Gokhale <gokhale2@llnl.gov>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Shaohua Li <shli@fb.com>
Link: http://lkml.kernel.org/r/20200220163112.11409-17-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:39 -07:00
David Rientjes
85b9f46e8e mm, thp: track fallbacks due to failed memcg charges separately
The thp_fault_fallback and thp_file_fallback vmstats are incremented if
either the hugepage allocation fails through the page allocator or the
hugepage charge fails through mem cgroup.

This patch leaves this field untouched but adds two new fields,
thp_{fault,file}_fallback_charge, which is incremented only when the mem
cgroup charge fails.

This distinguishes between attempted hugepage allocations that fail due to
fragmentation (or low memory conditions) and those that fail due to mem
cgroup limits.  That can be used to determine the impact of fragmentation
on the system by excluding faults that failed due to memcg usage.

Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Yang Shi <yang.shi@linux.alibaba.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Jeremy Cline <jcline@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Link: http://lkml.kernel.org/r/alpine.DEB.2.21.2003061422070.7412@chino.kir.corp.google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:38 -07:00
David Rientjes
dcdf11ee14 mm, shmem: add vmstat for hugepage fallback
The existing thp_fault_fallback indicates when thp attempts to allocate a
hugepage but fails, or if the hugepage cannot be charged to the mem cgroup
hierarchy.

Extend this to shmem as well.  Adds a new thp_file_fallback to complement
thp_file_alloc that gets incremented when a hugepage is attempted to be
allocated but fails, or if it cannot be charged to the mem cgroup
hierarchy.

Additionally, remove the check for CONFIG_TRANSPARENT_HUGE_PAGECACHE from
shmem_alloc_hugepage() since it is only called with this configuration
option.

Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Yang Shi <yang.shi@linux.alibaba.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Jeremy Cline <jcline@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Link: http://lkml.kernel.org/r/alpine.DEB.2.21.2003061421240.7412@chino.kir.corp.google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:38 -07:00
Dmitry Safonov
eeec26d5da time/namespace: Add max_time_namespaces ucount
Michael noticed that userns limit for number of time namespaces is missing.

Furthermore, time namespace introduced UCOUNT_TIME_NAMESPACES, but didn't
introduce an array member in user_table[]. It would make array's
initialisation OOB write, but by luck the user_table array has an excessive
empty member (all accesses to the array are limited with UCOUNT_COUNTS - so
it silently reuses the last free member.

Fixes user-visible regression: max_inotify_instances by reason of the
missing UCOUNT_ENTRY() has limited max number of namespaces instead of the
number of inotify instances.

Fixes: 769071ac9f ("ns: Introduce Time Namespace")
Reported-by: Michael Kerrisk (man-pages) <mtk.manpages@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Andrei Vagin <avagin@gmail.com>
Acked-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: stable@kernel.org
Link: https://lkml.kernel.org/r/20200406171342.128733-1-dima@arista.com
2020-04-07 12:37:21 +02:00
Linus Torvalds
7e63420847 Additional ACPI updates for 5.7-rc1
- Update the ACPICA code in the kernel to upstream revision 20200326
    including:
 
    * Fix for a typo in a comment field (Bob Moore).
    * acpiExec namespace init file fixes (Bob Moore).
    * Addition of NHLT to the known tables list (Cezary Rojewski).
    * Conversion of PlatformCommChannel ASL keyword to PCC (Erik
      Kaneda).
    * acpiexec cleanup (Erik Kaneda).
    * WSMT-related typo fix (Erik Kaneda).
    * sprintf() utility function fix (John Levon).
    * IVRS IVHD type 11h parsing implementation (Michał Żygowski).
    * IVRS IVHD type 10h reserved field name fix (Michał Żygowski).
 
  - Fix ACPI-related CPU hotplug deadlock on x86 (Qian Cai).
 
  - Fix Intel Tiger Lake ACPI device IDs in several places (Gayatri
    Kammela).
 
  - Add ACPI backlight blacklist entry for Acer Aspire 5783z (Hans
    de Goede).
 
  - Fix documentation of the "acpi_backlight" kernel command line
    switch (Randy Dunlap).
 
  - Clean up the acpi_get_psd_map() CPPC library routine (Liguang
    Zhang).
 -----BEGIN PGP SIGNATURE-----
 
 iQJGBAABCAAwFiEE4fcc61cGeeHD/fCwgsRv/nhiVHEFAl6LQEASHHJqd0Byand5
 c29ja2kubmV0AAoJEILEb/54YlRxqfoQAI/GPq7xhb8jOofmTfLxa4ahO2NDxK1E
 Ye4Tcm8JLv78hro7iMUlbPsRXm15lyDxMldGRfxsiLFTF2xQtYhdTnPx+KZ439j+
 QokMHUT6gFEMAV7OPFvXd2r58ShJJHezobbn241zTILx1c3ai66dCQrqyhYjlZ28
 0hUCyY4ilgXWuYInlckGW3Rp/Qxc9IVOxzFUV90EW9pTb4vKzoqznjNm+dpY8rHm
 QFNb2BkTJygOPmJiumi/yJX+74YSZrzW5fS1PDQS4Lr46j0imvWVVataMd1qbQ0+
 fDhvhL7IimHiM/qZg67hKpsAt6AcQPhaZ6JyoEGUoafxpBQN0a7b5rMwmL0P/HWV
 pL5mKM+jc7zh0HTb+xkpNotJxT+KBFo1jTRxGyVAnK8SThzlyFhKhetiOwaHCIDv
 dNYao6bCNsuGLh3T/09xbAmEeCSt7k+ok892N4o9wzqNfoDg6fX/c0M5ZD1F+Awb
 l9agU7XChziyDJwAqTbqndx71DK4ALrhZa1tNKA5PGTY8b5XrojoKsOyYk6PYA1x
 CqU20muRV4VAzB0pvdiwBc2Yrtfiv32mv5jMNrqrrv3D6S6R8vBUNhHlWKu/75a9
 9muIoEHWnK0/a9kmVJG8CUSXTTTPQpvOovesznruTxvGx3Mp9gw+d3/1tjuA/QNM
 ZoOOru5AEyi+
 =b3Dp
 -----END PGP SIGNATURE-----

Merge tag 'acpi-5.7-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull more ACPI updates from Rafael Wysocki:
 "Additional ACPI updates.

  These update the ACPICA code in the kernel to the 20200326 upstream
  revision, fix an ACPI-related CPU hotplug deadlock on x86, update
  Intel Tiger Lake device IDs in some places, add a new ACPI backlight
  blacklist entry, update the "acpi_backlight" kernel command line
  switch documentation and clean up a CPPC library routine.

  Specifics:

   - Update the ACPICA code in the kernel to upstream revision 20200326
     including:
      * Fix for a typo in a comment field (Bob Moore)
      * acpiExec namespace init file fixes (Bob Moore)
      * Addition of NHLT to the known tables list (Cezary Rojewski)
      * Conversion of PlatformCommChannel ASL keyword to PCC (Erik
        Kaneda)
      * acpiexec cleanup (Erik Kaneda)
      * WSMT-related typo fix (Erik Kaneda)
      * sprintf() utility function fix (John Levon)
      * IVRS IVHD type 11h parsing implementation (Michał Żygowski)
      * IVRS IVHD type 10h reserved field name fix (Michał Żygowski)

   - Fix ACPI-related CPU hotplug deadlock on x86 (Qian Cai)

   - Fix Intel Tiger Lake ACPI device IDs in several places (Gayatri
     Kammela)

   - Add ACPI backlight blacklist entry for Acer Aspire 5783z (Hans de
     Goede)

   - Fix documentation of the "acpi_backlight" kernel command line
     switch (Randy Dunlap)

   - Clean up the acpi_get_psd_map() CPPC library routine (Liguang
     Zhang)"

* tag 'acpi-5.7-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  x86: ACPI: fix CPU hotplug deadlock
  thermal: int340x_thermal: fix: Update Tiger Lake ACPI device IDs
  platform/x86: intel-hid: fix: Update Tiger Lake ACPI device ID
  ACPI: Update Tiger Lake ACPI device IDs
  ACPI: video: Use native backlight on Acer Aspire 5783z
  ACPI: video: Docs update for "acpi_backlight" kernel parameter options
  ACPICA: Update version 20200326
  ACPICA: Fixes for acpiExec namespace init file
  ACPICA: Add NHLT table signature
  ACPICA: WSMT: Fix typo, no functional change
  ACPICA: utilities: fix sprintf()
  ACPICA: acpiexec: remove redeclaration of acpi_gbl_db_opt_no_region_support
  ACPICA: Change PlatformCommChannel ASL keyword to PCC
  ACPICA: Fix IVRS IVHD type 10h reserved field name
  ACPICA: Implement IVRS IVHD type 11h parsing
  ACPICA: Fix a typo in a comment field
  ACPI: CPPC: clean up acpi_get_psd_map()
2020-04-06 10:35:06 -07:00
Linus Torvalds
ef05db16bb Additional power management updates for 5.7-rc1
- Fix corner-case suspend-to-idle wakeup issue on systems where
    the ACPI SCI is shared with another wakeup source (Hans de Goede).
 
  - Add document describing system-wide suspend and resume code flows
    to the admin guide (Rafael Wysocki).
 
  - Add kernel command line option to set pm_debug_messages (Chen Yu).
 
  - Choose schedutil as the preferred scaling governor by default on
    ARM big.LITTLE systems and on x86 systems using the intel_pstate
    driver in the passive mode (Linus Walleij, Rafael Wysocki).
 
  - Drop racy and redundant checks from the PM core's device_prepare()
    routine (Rafael Wysocki).
 
  - Make resume from hibernation take the hibernation_restore() return
    value into account (Dexuan Cui).
 -----BEGIN PGP SIGNATURE-----
 
 iQJGBAABCAAwFiEE4fcc61cGeeHD/fCwgsRv/nhiVHEFAl6LN9kSHHJqd0Byand5
 c29ja2kubmV0AAoJEILEb/54YlRxqj0P/3Uh16YIKOUeXosqtptJJiWgZoWu82aR
 H2uzc9hCV6k/tnSG/Y3ZGgI4dUZGcJ94By80XoWceZ97CC1YuBHpF/dHSupTCcvt
 tBEP9H2qbSLi9d2PhlEUJ0B6PBpWEjCzOb519Tzj4sd67FGhsKeihXl+WXdgaaKZ
 hpdj+tBkQ6Dxb7CXVw/mUpWlg/nmF+yRqpK5By+V0WMOlQtg4Ecb3lMqaJPr7b4F
 W/I5m4PE9QG+VetSSXoe7CKfLo2fsDtyHH6ioTJ9xklcOflIblZ3MYf3sKgOuuny
 m/6Zm71HmQwWRkjA/V+C/eTr0VX2TuMUALfA8i+uZBo//I58TTJq9oqosu8eao2P
 5MR79Vwa+eqtYRgpHCTM4JO1iyKiE+FTfVAPOS4hHOKjqY9BUj0YtWHxk8abdzQd
 owv9DjEtGKcipAnCKtWDIS9ikZ5TOsYiGgWyJQnoonpFY+0s3DwtRdi+gBLJliSj
 5j7sRv9wJrJRFZ7tRMHHAqoQkSYqf4YdBuRBG7F/M44anveORBJNaTbPgm30qbUP
 FXD9hTJn/4Q2nmBSzqvEv0+TJrWoCyKduzr5uNsR0eyg48w9mrlUDDkW7dOMb3DU
 WV6QGNomMuKIY4DHKCo3/k21NmzW2JN7zhUrErCnl0bXjV2AM71Cb2xjUD1eNOqV
 9LxPDvAmZoGt
 =QFDr
 -----END PGP SIGNATURE-----

Merge tag 'pm-5.7-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull more power management updates from Rafael Wysocki:
 "Additional power management updates.

  These fix a corner-case suspend-to-idle wakeup issue on systems where
  the ACPI SCI is shared with another wakeup source, add a kernel
  command line option to set pm_debug_messages via the kernel command
  line, add a document desctibing system-wide suspend and resume code
  flows, modify cpufreq Kconfig to choose schedutil as the preferred
  governor by default in a couple of cases and do some assorted
  cleanups.

  Specifics:

   - Fix corner-case suspend-to-idle wakeup issue on systems where the
     ACPI SCI is shared with another wakeup source (Hans de Goede).

   - Add document describing system-wide suspend and resume code flows
     to the admin guide (Rafael Wysocki).

   - Add kernel command line option to set pm_debug_messages (Chen Yu).

   - Choose schedutil as the preferred scaling governor by default on
     ARM big.LITTLE systems and on x86 systems using the intel_pstate
     driver in the passive mode (Linus Walleij, Rafael Wysocki).

   - Drop racy and redundant checks from the PM core's device_prepare()
     routine (Rafael Wysocki).

   - Make resume from hibernation take the hibernation_restore() return
     value into account (Dexuan Cui)"

* tag 'pm-5.7-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  platform/x86: intel_int0002_vgpio: Use acpi_register_wakeup_handler()
  ACPI: PM: Add acpi_[un]register_wakeup_handler()
  Documentation: PM: sleep: Document system-wide suspend code flows
  cpufreq: Select schedutil when using big.LITTLE
  PM: sleep: Add pm_debug_messages kernel command line option
  PM: sleep: core: Drop racy and redundant checks from device_prepare()
  PM: hibernate: Propagate the return value of hibernation_restore()
  cpufreq: intel_pstate: Select schedutil as the default governor
2020-04-06 10:14:39 -07:00
Linus Torvalds
0ad5b053d4 Char/Misc driver patches for 5.7-rc1
Here is the big set of char/misc/other driver patches for 5.7-rc1.
 
 Lots of things in here, and it's later than expected due to some reverts
 to resolve some reported issues.  All is now clean with no reported
 problems in linux-next.
 
 Included in here is:
 	- interconnect updates
 	- mei driver updates
 	- uio updates
 	- nvmem driver updates
 	- soundwire updates
 	- binderfs updates
 	- coresight updates
 	- habanalabs updates
 	- mhi new bus type and core
 	- extcon driver updates
 	- some Kconfig cleanups
 	- other small misc driver cleanups and updates
 
 As mentioned, all have been in linux-next for a while, and with the last
 two reverts, all is calm and good.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCXodfvA8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+ynzCQCfROhar3E8EhYEqSOP6xq6uhX9uegAnRgGY2rs
 rN4JJpOcTddvZcVlD+vo
 =ocWk
 -----END PGP SIGNATURE-----

Merge tag 'char-misc-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the big set of char/misc/other driver patches for 5.7-rc1.

  Lots of things in here, and it's later than expected due to some
  reverts to resolve some reported issues. All is now clean with no
  reported problems in linux-next.

  Included in here is:
   - interconnect updates
   - mei driver updates
   - uio updates
   - nvmem driver updates
   - soundwire updates
   - binderfs updates
   - coresight updates
   - habanalabs updates
   - mhi new bus type and core
   - extcon driver updates
   - some Kconfig cleanups
   - other small misc driver cleanups and updates

  As mentioned, all have been in linux-next for a while, and with the
  last two reverts, all is calm and good"

* tag 'char-misc-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (174 commits)
  Revert "driver core: platform: Initialize dma_parms for platform devices"
  Revert "amba: Initialize dma_parms for amba devices"
  amba: Initialize dma_parms for amba devices
  driver core: platform: Initialize dma_parms for platform devices
  bus: mhi: core: Drop the references to mhi_dev in mhi_destroy_device()
  bus: mhi: core: Initialize bhie field in mhi_cntrl for RDDM capture
  bus: mhi: core: Add support for reading MHI info from device
  misc: rtsx: set correct pcr_ops for rts522A
  speakup: misc: Use dynamic minor numbers for speakup devices
  mei: me: add cedar fork device ids
  coresight: do not use the BIT() macro in the UAPI header
  Documentation: provide IBM contacts for embargoed hardware
  nvmem: core: remove nvmem_sysfs_get_groups()
  nvmem: core: use is_bin_visible for permissions
  nvmem: core: use device_register and device_unregister
  nvmem: core: add root_only member to nvmem device struct
  extcon: axp288: Add wakeup support
  extcon: Mark extcon_get_edev_name() function as exported symbol
  extcon: palmas: Hide error messages if gpio returns -EPROBE_DEFER
  dt-bindings: extcon: usbc-cros-ec: convert extcon-usbc-cros-ec.txt to yaml format
  ...
2020-04-03 13:22:40 -07:00
Linus Torvalds
d883600523 Merge branch 'for-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:

 - Christian extended clone3 so that processes can be spawned into
   cgroups directly.

   This is not only neat in terms of semantics but also avoids grabbing
   the global cgroup_threadgroup_rwsem for migration.

 - Daniel added !root xattr support to cgroupfs.

   Userland already uses xattrs on cgroupfs for bookkeeping. This will
   allow delegated cgroups to support such usages.

 - Prateek tried to make cpuset hotplug handling synchronous but that
   led to possible deadlock scenarios. Reverted.

 - Other minor changes including release_agent_path handling cleanup.

* 'for-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  docs: cgroup-v1: Document the cpuset_v2_mode mount option
  Revert "cpuset: Make cpuset hotplug synchronous"
  cgroupfs: Support user xattrs
  kernfs: Add option to enable user xattrs
  kernfs: Add removed_size out param for simple_xattr_set
  kernfs: kvmalloc xattr value instead of kmalloc
  cgroup: Restructure release_agent_path handling
  selftests/cgroup: add tests for cloning into cgroups
  clone3: allow spawning processes into cgroups
  cgroup: add cgroup_may_write() helper
  cgroup: refactor fork helpers
  cgroup: add cgroup_get_from_file() helper
  cgroup: unify attach permission checking
  cpuset: Make cpuset hotplug synchronous
  cgroup.c: Use built-in RCU list checking
  kselftest/cgroup: add cgroup destruction test
  cgroup: Clean up css_set task traversal
2020-04-03 11:30:20 -07:00
Waiman Long
0c05b9bdbf docs: cgroup-v1: Document the cpuset_v2_mode mount option
The cpuset in cgroup v1 accepts a special "cpuset_v2_mode" mount
option that make cpuset.cpus and cpuset.mems behave more like those in
cgroup v2.  Document it to make other people more aware of this feature
that can be useful in some circumstances.

Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2020-04-03 11:42:56 -04:00
Rafael J. Wysocki
4506c531f1 Documentation: PM: sleep: Document system-wide suspend code flows
Add a document describing high-level system-wide suspend code flows
in Linux.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-04-03 11:41:01 +02:00
Linus Torvalds
8c1b724ddb ARM:
* GICv4.1 support
 * 32bit host removal
 
 PPC:
 * secure (encrypted) using under the Protected Execution Framework
 ultravisor
 
 s390:
 * allow disabling GISA (hardware interrupt injection) and protected
 VMs/ultravisor support.
 
 x86:
 * New dirty bitmap flag that sets all bits in the bitmap when dirty
 page logging is enabled; this is faster because it doesn't require bulk
 modification of the page tables.
 * Initial work on making nested SVM event injection more similar to VMX,
 and less buggy.
 * Various cleanups to MMU code (though the big ones and related
 optimizations were delayed to 5.8).  Instead of using cr3 in function
 names which occasionally means eptp, KVM too has standardized on "pgd".
 * A large refactoring of CPUID features, which now use an array that
 parallels the core x86_features.
 * Some removal of pointer chasing from kvm_x86_ops, which will also be
 switched to static calls as soon as they are available.
 * New Tigerlake CPUID features.
 * More bugfixes, optimizations and cleanups.
 
 Generic:
 * selftests: cleanups, new MMU notifier stress test, steal-time test
 * CSV output for kvm_stat.
 
 KVM/MIPS has been broken since 5.5, it does not compile due to a patch committed
 by MIPS maintainers.  I had already prepared a fix, but the MIPS maintainers
 prefer to fix it in generic code rather than KVM so they are taking care of it.
 -----BEGIN PGP SIGNATURE-----
 
 iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAl6GOnIUHHBib256aW5p
 QHJlZGhhdC5jb20ACgkQv/vSX3jHroMfxwf/ZKLZiRoaovXCOG71M/eHtQb8ZIqU
 3MPy+On3eC5Sk/aBxWUL9EFZsbYG6kYdbZ1VOvG9XPBoLlnkDSm/IR0kaELHtnjj
 oGVda/tvGn46Ne39y8xBptmb91WDcWH0vFthT/CwlMxAw3xjr+gG7Qyo+8F2CW6m
 SSSuLiHSBnyO1cQKruBTHZ8qnR8LlnfXEqtd6Y4LFLic0LbLIoIdRcT3wjQrcZrm
 Djd7wbTEYZjUfoqZ72ekwEDUsONcDLDSKcguDO9pSMSCGhpxCVT5Vy68KRpoIMs2
 nzNWDKjvqQo5zb2+GWxJgkd12Hv+n7PCXZMbVrWBu1pQsewUns9m4mkpGw==
 =6fGt
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "ARM:
   - GICv4.1 support

   - 32bit host removal

  PPC:
   - secure (encrypted) using under the Protected Execution Framework
     ultravisor

  s390:
   - allow disabling GISA (hardware interrupt injection) and protected
     VMs/ultravisor support.

  x86:
   - New dirty bitmap flag that sets all bits in the bitmap when dirty
     page logging is enabled; this is faster because it doesn't require
     bulk modification of the page tables.

   - Initial work on making nested SVM event injection more similar to
     VMX, and less buggy.

   - Various cleanups to MMU code (though the big ones and related
     optimizations were delayed to 5.8). Instead of using cr3 in
     function names which occasionally means eptp, KVM too has
     standardized on "pgd".

   - A large refactoring of CPUID features, which now use an array that
     parallels the core x86_features.

   - Some removal of pointer chasing from kvm_x86_ops, which will also
     be switched to static calls as soon as they are available.

   - New Tigerlake CPUID features.

   - More bugfixes, optimizations and cleanups.

  Generic:
   - selftests: cleanups, new MMU notifier stress test, steal-time test

   - CSV output for kvm_stat"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (277 commits)
  x86/kvm: fix a missing-prototypes "vmread_error"
  KVM: x86: Fix BUILD_BUG() in __cpuid_entry_get_reg() w/ CONFIG_UBSAN=y
  KVM: VMX: Add a trampoline to fix VMREAD error handling
  KVM: SVM: Annotate svm_x86_ops as __initdata
  KVM: VMX: Annotate vmx_x86_ops as __initdata
  KVM: x86: Drop __exit from kvm_x86_ops' hardware_unsetup()
  KVM: x86: Copy kvm_x86_ops by value to eliminate layer of indirection
  KVM: x86: Set kvm_x86_ops only after ->hardware_setup() completes
  KVM: VMX: Configure runtime hooks using vmx_x86_ops
  KVM: VMX: Move hardware_setup() definition below vmx_x86_ops
  KVM: x86: Move init-only kvm_x86_ops to separate struct
  KVM: Pass kvm_init()'s opaque param to additional arch funcs
  s390/gmap: return proper error code on ksm unsharing
  KVM: selftests: Fix cosmetic copy-paste error in vm_mem_region_move()
  KVM: Fix out of range accesses to memslots
  KVM: X86: Micro-optimize IPI fastpath delay
  KVM: X86: Delay read msr data iff writes ICR MSR
  KVM: PPC: Book3S HV: Add a capability for enabling secure guests
  KVM: arm64: GICv4.1: Expose HW-based SGIs in debugfs
  KVM: arm64: GICv4.1: Allow non-trapping WFI when using HW SGIs
  ...
2020-04-02 15:13:15 -07:00
Linus Torvalds
6cad420cc6 Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:
 "A large amount of MM, plenty more to come.

  Subsystems affected by this patch series:
   - tools
   - kthread
   - kbuild
   - scripts
   - ocfs2
   - vfs
   - mm: slub, kmemleak, pagecache, gup, swap, memcg, pagemap, mremap,
         sparsemem, kasan, pagealloc, vmscan, compaction, mempolicy,
         hugetlbfs, hugetlb"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (155 commits)
  include/linux/huge_mm.h: check PageTail in hpage_nr_pages even when !THP
  mm/hugetlb: fix build failure with HUGETLB_PAGE but not HUGEBTLBFS
  selftests/vm: fix map_hugetlb length used for testing read and write
  mm/hugetlb: remove unnecessary memory fetch in PageHeadHuge()
  mm/hugetlb.c: clean code by removing unnecessary initialization
  hugetlb_cgroup: add hugetlb_cgroup reservation docs
  hugetlb_cgroup: add hugetlb_cgroup reservation tests
  hugetlb: support file_region coalescing again
  hugetlb_cgroup: support noreserve mappings
  hugetlb_cgroup: add accounting for shared mappings
  hugetlb: disable region_add file_region coalescing
  hugetlb_cgroup: add reservation accounting for private mappings
  mm/hugetlb_cgroup: fix hugetlb_cgroup migration
  hugetlb_cgroup: add interface for charge/uncharge hugetlb reservations
  hugetlb_cgroup: add hugetlb_cgroup reservation counter
  hugetlbfs: Use i_mmap_rwsem to address page fault/truncate race
  hugetlbfs: use i_mmap_rwsem for more pmd sharing synchronization
  mm/memblock.c: remove redundant assignment to variable max_addr
  mm: mempolicy: require at least one nodeid for MPOL_PREFERRED
  mm: mempolicy: use VM_BUG_ON_VMA in queue_pages_test_walk()
  ...
2020-04-02 13:55:34 -07:00
Mina Almasry
6566704daf hugetlb_cgroup: add hugetlb_cgroup reservation docs
Add docs for how to use hugetlb_cgroup reservations, and their behavior.

Signed-off-by: Mina Almasry <almasrymina@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Sandipan Das <sandipan@linux.ibm.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Link: http://lkml.kernel.org/r/20200211213128.73302-9-almasrymina@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:32 -07:00
Sebastian Andrzej Siewior
6923aa0d8c mm/compaction: Disable compact_unevictable_allowed on RT
Since commit 5bbe3547aa ("mm: allow compaction of unevictable pages")
it is allowed to examine mlocked pages and compact them by default.  On
-RT even minor pagefaults are problematic because it may take a few 100us
to resolve them and until then the task is blocked.

Make compact_unevictable_allowed = 0 default and issue a warning on RT if
it is changed.

[bigeasy@linutronix.de: v5]
  Link: https://lore.kernel.org/linux-mm/20190710144138.qyn4tuttdq6h7kqx@linutronix.de/
  Link: http://lkml.kernel.org/r/20200319165536.ovi75tsr2seared4@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Link: https://lore.kernel.org/linux-mm/20190710144138.qyn4tuttdq6h7kqx@linutronix.de/
Link: http://lkml.kernel.org/r/20200303202225.nhqc3v5gwlb7x6et@linutronix.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:31 -07:00
Johannes Weiner
8a931f8013 mm: memcontrol: recursive memory.low protection
Right now, the effective protection of any given cgroup is capped by its
own explicit memory.low setting, regardless of what the parent says.  The
reasons for this are mostly historical and ease of implementation: to make
delegation of memory.low safe, effective protection is the min() of all
memory.low up the tree.

Unfortunately, this limitation makes it impossible to protect an entire
subtree from another without forcing the user to make explicit protection
allocations all the way to the leaf cgroups - something that is highly
undesirable in real life scenarios.

Consider memory in a data center host.  At the cgroup top level, we have a
distinction between system management software and the actual workload the
system is executing.  Both branches are further subdivided into individual
services, job components etc.

We want to protect the workload as a whole from the system management
software, but that doesn't mean we want to protect and prioritize
individual workload wrt each other.  Their memory demand can vary over
time, and we'd want the VM to simply cache the hottest data within the
workload subtree.  Yet, the current memory.low limitations force us to
allocate a fixed amount of protection to each workload component in order
to get protection from system management software in general.  This
results in very inefficient resource distribution.

Another concern with mandating downward allocation is that, as the
complexity of the cgroup tree grows, it gets harder for the lower levels
to be informed about decisions made at the host-level.  Consider a
container inside a namespace that in turn creates its own nested tree of
cgroups to run multiple workloads.  It'd be extremely difficult to
configure memory.low parameters in those leaf cgroups that on one hand
balance pressure among siblings as the container desires, while also
reflecting the host-level protection from e.g.  rpm upgrades, that lie
beyond one or more delegation and namespacing points in the tree.

It's highly unusual from a cgroup interface POV that nested levels have to
be aware of and reflect decisions made at higher levels for them to be
effective.

To enable such use cases and scale configurability for complex trees, this
patch implements a resource inheritance model for memory that is similar
to how the CPU and the IO controller implement work-conserving resource
allocations: a share of a resource allocated to a subree always applies to
the entire subtree recursively, while allowing, but not mandating,
children to further specify distribution rules.

That means that if protection is explicitly allocated among siblings,
those configured shares are being followed during page reclaim just like
they are now.  However, if the memory.low set at a higher level is not
fully claimed by the children in that subtree, the "floating" remainder is
applied to each cgroup in the tree in proportion to its size.  Since
reclaim pressure is applied in proportion to size as well, each child in
that tree gets the same boost, and the effect is neutral among siblings -
with respect to each other, they behave as if no memory control was
enabled at all, and the VM simply balances the memory demands optimally
within the subtree.  But collectively those cgroups enjoy a boost over the
cgroups in neighboring trees.

E.g.  a leaf cgroup with a memory.low setting of 0 no longer means that
it's not getting a share of the hierarchically assigned resource, just
that it doesn't claim a fixed amount of it to protect from its siblings.

This allows us to recursively protect one subtree (workload) from another
(system management), while letting subgroups compete freely among each
other - without having to assign fixed shares to each leaf, and without
nested groups having to echo higher-level settings.

The floating protection composes naturally with fixed protection.
Consider the following example tree:

		A            A: low = 2G
               / \          A1: low = 1G
              A1 A2         A2: low = 0G

As outside pressure is applied to this tree, A1 will enjoy a fixed
protection from A2 of 1G, but the remaining, unclaimed 1G from A is split
evenly among A1 and A2, coming out to 1.5G and 0.5G.

There is a slight risk of regressing theoretical setups where the
top-level cgroups don't know about the true budgeting and set bogusly high
"bypass" values that are meaningfully allocated down the tree.  Such
setups would rely on unclaimed protection to be discarded, and
distributing it would change the intended behavior.  Be safe and hide the
new behavior behind a mount option, 'memory_recursiveprot'.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: Chris Down <chris@chrisdown.name>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michal Koutný <mkoutny@suse.com>
Link: http://lkml.kernel.org/r/20200227195606.46212-4-hannes@cmpxchg.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-02 09:35:28 -07:00
Chen Yu
db96a75946 PM: sleep: Add pm_debug_messages kernel command line option
Debug messages from the system suspend/hibernation infrastructure
are disabled by default, and can only be enabled after the system
has boot up via /sys/power/pm_debug_messages.

This makes the hibernation resume hard to track as it involves system
boot up across hibernation.  There's no chance for software_resume()
to track the resume process, for example.

Add a kernel command line option to set pm_debug_messages during
boot up.

Signed-off-by: Chen Yu <yu.c.chen@intel.com>
[ rjw: Subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-04-02 15:29:56 +02:00
Linus Torvalds
69c1fd9726 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina:
 "My attempt to revitalize trivial queue I've been neglecting for years
  (what a disaster that was for this world, right? :) ) with patches
  collected from backlog that were still relevant and not applied
  elsewhere in the meantime"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
  err.h: remove deprecated PTR_RET for good
  blk-mq: Fix typo in comment
  x86/boot: Fix comment spelling
  sh: mach-highlander: Fix comment spelling
  s390/dasd: Fix comment spelling
  mfd: wm8994: Fix comment spelling
  docs: Add reference in binfmt-misc.rst
  genirq: fix kerneldoc comment for irq_desc
  drm/amdgpu: fix two documentation mismatch issues
  HID: fix Kconfig word ordering
  list/hashtable: minor documentation corrections.
2020-04-01 14:52:59 -07:00
Randy Dunlap
5fd769c2bf ACPI: video: Docs update for "acpi_backlight" kernel parameter options
Update the Documentation for "acpi_backlight" by adding 2 new
options (native and none).

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-04-01 11:15:55 +02:00
Linus Torvalds
29d9f30d4c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:
 "Highlights:

   1) Fix the iwlwifi regression, from Johannes Berg.

   2) Support BSS coloring and 802.11 encapsulation offloading in
      hardware, from John Crispin.

   3) Fix some potential Spectre issues in qtnfmac, from Sergey
      Matyukevich.

   4) Add TTL decrement action to openvswitch, from Matteo Croce.

   5) Allow paralleization through flow_action setup by not taking the
      RTNL mutex, from Vlad Buslov.

   6) A lot of zero-length array to flexible-array conversions, from
      Gustavo A. R. Silva.

   7) Align XDP statistics names across several drivers for consistency,
      from Lorenzo Bianconi.

   8) Add various pieces of infrastructure for offloading conntrack, and
      make use of it in mlx5 driver, from Paul Blakey.

   9) Allow using listening sockets in BPF sockmap, from Jakub Sitnicki.

  10) Lots of parallelization improvements during configuration changes
      in mlxsw driver, from Ido Schimmel.

  11) Add support to devlink for generic packet traps, which report
      packets dropped during ACL processing. And use them in mlxsw
      driver. From Jiri Pirko.

  12) Support bcmgenet on ACPI, from Jeremy Linton.

  13) Make BPF compatible with RT, from Thomas Gleixnet, Alexei
      Starovoitov, and your's truly.

  14) Support XDP meta-data in virtio_net, from Yuya Kusakabe.

  15) Fix sysfs permissions when network devices change namespaces, from
      Christian Brauner.

  16) Add a flags element to ethtool_ops so that drivers can more simply
      indicate which coalescing parameters they actually support, and
      therefore the generic layer can validate the user's ethtool
      request. Use this in all drivers, from Jakub Kicinski.

  17) Offload FIFO qdisc in mlxsw, from Petr Machata.

  18) Support UDP sockets in sockmap, from Lorenz Bauer.

  19) Fix stretch ACK bugs in several TCP congestion control modules,
      from Pengcheng Yang.

  20) Support virtual functiosn in octeontx2 driver, from Tomasz
      Duszynski.

  21) Add region operations for devlink and use it in ice driver to dump
      NVM contents, from Jacob Keller.

  22) Add support for hw offload of MACSEC, from Antoine Tenart.

  23) Add support for BPF programs that can be attached to LSM hooks,
      from KP Singh.

  24) Support for multiple paths, path managers, and counters in MPTCP.
      From Peter Krystad, Paolo Abeni, Florian Westphal, Davide Caratti,
      and others.

  25) More progress on adding the netlink interface to ethtool, from
      Michal Kubecek"

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2121 commits)
  net: ipv6: rpl_iptunnel: Fix potential memory leak in rpl_do_srh_inline
  cxgb4/chcr: nic-tls stats in ethtool
  net: dsa: fix oops while probing Marvell DSA switches
  net/bpfilter: remove superfluous testing message
  net: macb: Fix handling of fixed-link node
  net: dsa: ksz: Select KSZ protocol tag
  netdevsim: dev: Fix memory leak in nsim_dev_take_snapshot_write
  net: stmmac: add EHL 2.5Gbps PCI info and PCI ID
  net: stmmac: add EHL PSE0 & PSE1 1Gbps PCI info and PCI ID
  net: stmmac: create dwmac-intel.c to contain all Intel platform
  net: dsa: bcm_sf2: Support specifying VLAN tag egress rule
  net: dsa: bcm_sf2: Add support for matching VLAN TCI
  net: dsa: bcm_sf2: Move writing of CFP_DATA(5) into slicing functions
  net: dsa: bcm_sf2: Check earlier for FLOW_EXT and FLOW_MAC_EXT
  net: dsa: bcm_sf2: Disable learning for ASP port
  net: dsa: b53: Deny enslaving port 7 for 7278 into a bridge
  net: dsa: b53: Prevent tagged VLAN on port 7 for 7278
  net: dsa: b53: Restore VLAN entries upon (re)configuration
  net: dsa: bcm_sf2: Fix overflow checks
  hv_netvsc: Remove unnecessary round_up for recv_completion_cnt
  ...
2020-03-31 17:29:33 -07:00
Linus Torvalds
b3aa112d57 selinux/stable-5.7 PR 20200330
-----BEGIN PGP SIGNATURE-----
 
 iQJIBAABCAAyFiEES0KozwfymdVUl37v6iDy2pc3iXMFAl6Ch6wUHHBhdWxAcGF1
 bC1tb29yZS5jb20ACgkQ6iDy2pc3iXPdcg/9FDMS/n0Xl1HQBUyu26EwLu3aUpNE
 BdghXW1LKSTp7MrOENE60PGzZSAiC07ci1DqFd7zfLPZf2q5IwPwOBa/Avy8z95V
 oHKqcMT6WO1SPOm/PxZn16FCKyET4gZDTXvHBAyiyFsbk36R522ZY615P9T3eLu/
 ZA1NFsSjj68SqMCUlAWfeqjcbQiX63bryEpugOIg0qWy7R/+rtWxj9TjriZ+v9tq
 uC45UcjBqphpmoPG8BifA3jjyclwO3DeQb5u7E8//HPPraGeB19ntsymUg7ljoGk
 NrqCkZtv6E+FRCDTR5f0O7M1T4BWJodxw2NwngnTwKByLC25EZaGx80o+VyMt0eT
 Pog+++JZaa5zZr2OYOtdlPVMLc2ALL6p/8lHOqFU3GKfIf04hWOm6/Lb2IWoXs3f
 CG2b6vzoXYyjbF0Q7kxadb8uBY2S1Ds+CVu2HMBBsXsPdwbbtFWOT/6aRAQu61qn
 PW+f47NR8By3SO6nMzWts2SZEERZNIEdSKeXHuR7As1jFMXrHLItreb4GCSPay5h
 2bzRpxt2br5CDLh7Jv2pZnHtUqBWOSbslTix77+Z/hPKaNowvD9v3tc5hX87rDmB
 dYXROD6/KoyXFYDcMdphlvORFhqGqd5bEYuHHum/VjSIRh237+/nxFY/vZ4i4bzU
 2fvpAmUlVX1c4rw=
 =LlWA
 -----END PGP SIGNATURE-----

Merge tag 'selinux-pr-20200330' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux

Pull SELinux updates from Paul Moore:
 "We've got twenty SELinux patches for the v5.7 merge window, the
  highlights are below:

   - Deprecate setting /sys/fs/selinux/checkreqprot to 1.

     This flag was originally created to deal with legacy userspace and
     the READ_IMPLIES_EXEC personality flag. We changed the default from
     1 to 0 back in Linux v4.4 and now we are taking the next step of
     deprecating it, at some point in the future we will take the final
     step of rejecting 1.

   - Allow kernfs symlinks to inherit the SELinux label of the parent
     directory. In order to preserve backwards compatibility this is
     protected by the genfs_seclabel_symlinks SELinux policy capability.

   - Optimize how we store filename transitions in the kernel, resulting
     in some significant improvements to policy load times.

   - Do a better job calculating our internal hash table sizes which
     resulted in additional policy load improvements and likely general
     SELinux performance improvements as well.

   - Remove the unused initial SIDs (labels) and improve how we handle
     initial SIDs.

   - Enable per-file labeling for the bpf filesystem.

   - Ensure that we properly label NFS v4.2 filesystems to avoid a
     temporary unlabeled condition.

   - Add some missing XFS quota command types to the SELinux quota
     access controls.

   - Fix a problem where we were not updating the seq_file position
     index correctly in selinuxfs.

   - We consolidate some duplicated code into helper functions.

   - A number of list to array conversions.

   - Update Stephen Smalley's email address in MAINTAINERS"

* tag 'selinux-pr-20200330' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  selinux: clean up indentation issue with assignment statement
  NFS: Ensure security label is set for root inode
  MAINTAINERS: Update my email address
  selinux: avtab_init() and cond_policydb_init() return void
  selinux: clean up error path in policydb_init()
  selinux: remove unused initial SIDs and improve handling
  selinux: reduce the use of hard-coded hash sizes
  selinux: Add xfs quota command types
  selinux: optimize storage of filename transitions
  selinux: factor out loop body from filename_trans_read()
  security: selinux: allow per-file labeling for bpffs
  selinux: generalize evaluate_cond_node()
  selinux: convert cond_expr to array
  selinux: convert cond_av_list to array
  selinux: convert cond_list to array
  selinux: sel_avc_get_stat_idx should increase position index
  selinux: allow kernfs symlinks to inherit parent directory context
  selinux: simplify evaluate_cond_node()
  Documentation,selinux: deprecate setting checkreqprot to 1
  selinux: move status variables out of selinux_ss
2020-03-31 15:07:55 -07:00
Linus Torvalds
42595ce90b Merge branch 'x86-vmware-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 vmware updates from Ingo Molnar:
 "The main change in this tree is the addition of 'steal time clock
  support' for VMware guests"

* 'x86-vmware-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/vmware: Use bool type for vmw_sched_clock
  x86/vmware: Enable steal time accounting
  x86/vmware: Add steal time clock support for VMware guests
  x86/vmware: Remove vmware_sched_clock_setup()
  x86/vmware: Make vmware_select_hypercall() __init
2020-03-31 12:09:51 -07:00
Paolo Bonzini
cf39d37539 KVM/arm updates for Linux 5.7
- GICv4.1 support
 - 32bit host removal
 -----BEGIN PGP SIGNATURE-----
 
 iQJDBAABCgAtFiEEn9UcU+C1Yxj9lZw9I9DQutE9ekMFAl6DKKIPHG1hekBrZXJu
 ZWwub3JnAAoJECPQ0LrRPXpDDe0P/30Oda6HJdcUY+g0dnHkH8N7t+VKjPPnihlX
 WBaT0Y4SzMsfAtG5lQqS48A50dXKWW70QvwkZjxu7abQhYFWGd2SGtTQxwqJXT8J
 I6MBh4r9xrIfiqzVT2BXslA6id5H6wCyyFI6vKm/IFkIu1J6JtwnKakQ0CIddS1d
 Blbgj5jcxGw+2xOppHCQXbWwwDdmYWkMZEBZjmhkezddqLDK+oaAUiUhHHHizTsB
 kLjgqYBVENpR1zDIsGpQAJloKXAiHfBQshQAmnhnBNzXE60LZ0n0/iODU9U5FDEO
 5j0DRWccKvsIMsUh7JpPr5xerGJ0rqk1IwPC2JcyzfRbvRLMpK1IOWfhI5Tg5lbP
 4Ev96QLEMBnKOWMSE0MqnMdq6JPzDLA6WZ28HZe2nc3/oWNgsSDtlXigx4xFFxTX
 zfc2YpAgFu3xJkPf8PtWTFvItm0AvFNFynPg0Rr/NsGf/FGeszYR4cLcHmv5NlWS
 IiV4+lgnlmr2LZr3VjUaumbtWIpuVF4Db5Al2K2E/PCN7ObfEkyCweDic8ophkH8
 sMS9TI38aH1Efy+I2Nfxxqpy8BcElZAMrAWt9R27A4JRLHdr7j5DsGnyRigXHgRe
 pFgbqtk/EjWkHwjaJVg8kPxf2+2P05VZsQeGG721nbKAIKDetM3RA2BflexdsptY
 kXplNsVr
 =eILh
 -----END PGP SIGNATURE-----

Merge tag 'kvmarm-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm updates for Linux 5.7

- GICv4.1 support
- 32bit host removal
2020-03-31 10:44:53 -04:00
Linus Torvalds
2853d5fafb Support for "split lock" detection:
- Atomic operations (lock prefixed instructions) which span two cache
     lines have to acquire the global bus lock. This is at least 1k cycles
     slower than an atomic operation within a cache line and disrupts
     performance on other cores. Aside of performance disruption this is
     a unpriviledged form of DoS.
 
     Some newer CPUs have the capability to raise an #AC trap when such an
     operation is attempted. The detection is by default enabled in warning
     mode which will warn once when a user space application is caught. A
     command line option allows to disable the detection or to select fatal
     mode which will terminate offending applications with SIGBUS.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl6B/uMTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYocsAD/9yqpw+XlPKNPsfbm9sbirBDfTrENcL
 F44iwn4WnrjoW/gnnZCYmPxJFsTtGVPqxHdUf4eyGemg9r9ZEO0DQftmUHC5Z6KX
 aa/b5JoeM61wp9HlpVlD4D1jVt4pWyQODQeZnUXE4DEzmRc3cD/5lSU+/VeaIwwz
 lxwUemqmXK7ucH2KA7smOGsl2nU6ED84q3mdOB1b4Cw+gWYMUnPJnuS/ipriBRx4
 BYbMItcxsFvtdO9Hx8PvGd5LUK0wW8JOWrYQICD2kLpZtHtGeaHpBzFzL0+nMU7d
 1epyDqJQDmX+PAzvj+EYyn3HTfobZlckn+tbxMQkkS+oDk1ywOZd+BancClvn5/5
 jMfPIQJF5bGASVnzGMWhzVdwthTZiMG4d1iKsUWOA/hN0ch0+rm1BqraToabsEFg
 Sv7/rvl9KtSOtMJTeAmMhlZUMBj9m8BtPFjniDwp6nw/upGgJdST5mrKFNYZvqOj
 JnXsEMr/nJVW6bnUvT6LF66xbHlzHdxtodkQWqF+IEsyRaOz1zAGpQamP98KxNLc
 dq/XYoEe1KqIFbg4BkNP+GeDL3FQDxjFNwPQnnjQEzWRbjkHlfmq1uKCsR2r8mBO
 fYNJ1X8lTyGV0kx/ERpWGazzabpzh+8Lr1yMhnoA3EWvlzUjmpN2PFI4oTpTrtzT
 c/q16SCxim3NWA==
 =D9x8
 -----END PGP SIGNATURE-----

Merge tag 'x86-splitlock-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 splitlock updates from Thomas Gleixner:
 "Support for 'split lock' detection:

  Atomic operations (lock prefixed instructions) which span two cache
  lines have to acquire the global bus lock. This is at least 1k cycles
  slower than an atomic operation within a cache line and disrupts
  performance on other cores. Aside of performance disruption this is a
  unpriviledged form of DoS.

  Some newer CPUs have the capability to raise an #AC trap when such an
  operation is attempted. The detection is by default enabled in warning
  mode which will warn once when a user space application is caught. A
  command line option allows to disable the detection or to select fatal
  mode which will terminate offending applications with SIGBUS"

* tag 'x86-splitlock-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/split_lock: Avoid runtime reads of the TEST_CTRL MSR
  x86/split_lock: Rework the initialization flow of split lock detection
  x86/split_lock: Enable split lock detection by kernel
2020-03-30 19:35:52 -07:00
Linus Torvalds
642e53ead6 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "The main changes in this cycle are:

   - Various NUMA scheduling updates: harmonize the load-balancer and
     NUMA placement logic to not work against each other. The intended
     result is better locality, better utilization and fewer migrations.

   - Introduce Thermal Pressure tracking and optimizations, to improve
     task placement on thermally overloaded systems.

   - Implement frequency invariant scheduler accounting on (some) x86
     CPUs. This is done by observing and sampling the 'recent' CPU
     frequency average at ~tick boundaries. The CPU provides this data
     via the APERF/MPERF MSRs. This hopefully makes our capacity
     estimates more precise and keeps tasks on the same CPU better even
     if it might seem overloaded at a lower momentary frequency. (As
     usual, turbo mode is a complication that we resolve by observing
     the maximum frequency and renormalizing to it.)

   - Add asymmetric CPU capacity wakeup scan to improve capacity
     utilization on asymmetric topologies. (big.LITTLE systems)

   - PSI fixes and optimizations.

   - RT scheduling capacity awareness fixes & improvements.

   - Optimize the CONFIG_RT_GROUP_SCHED constraints code.

   - Misc fixes, cleanups and optimizations - see the changelog for
     details"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (62 commits)
  threads: Update PID limit comment according to futex UAPI change
  sched/fair: Fix condition of avg_load calculation
  sched/rt: cpupri_find: Trigger a full search as fallback
  kthread: Do not preempt current task if it is going to call schedule()
  sched/fair: Improve spreading of utilization
  sched: Avoid scale real weight down to zero
  psi: Move PF_MEMSTALL out of task->flags
  MAINTAINERS: Add maintenance information for psi
  psi: Optimize switching tasks inside shared cgroups
  psi: Fix cpu.pressure for cpu.max and competing cgroups
  sched/core: Distribute tasks within affinity masks
  sched/fair: Fix enqueue_task_fair warning
  thermal/cpu-cooling, sched/core: Move the arch_set_thermal_pressure() API to generic scheduler code
  sched/rt: Remove unnecessary push for unfit tasks
  sched/rt: Allow pulling unfitting task
  sched/rt: Optimize cpupri_find() on non-heterogenous systems
  sched/rt: Re-instate old behavior in select_task_rq_rt()
  sched/rt: cpupri_find: Implement fallback mechanism for !fit case
  sched/fair: Fix reordering of enqueue/dequeue_task_fair()
  sched/fair: Fix runnable_avg for throttled cfs
  ...
2020-03-30 17:01:51 -07:00
Linus Torvalds
7c4fa15071 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Make kfree_rcu() use kfree_bulk() for added performance

   - RCU updates

   - Callback-overload handling updates

   - Tasks-RCU KCSAN and sparse updates

   - Locking torture test and RCU torture test updates

   - Documentation updates

   - Miscellaneous fixes"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (74 commits)
  rcu: Make rcu_barrier() account for offline no-CBs CPUs
  rcu: Mark rcu_state.gp_seq to detect concurrent writes
  Documentation/memory-barriers: Fix typos
  doc: Add rcutorture scripting to torture.txt
  doc/RCU/rcu: Use https instead of http if possible
  doc/RCU/rcu: Use absolute paths for non-rst files
  doc/RCU/rcu: Use ':ref:' for links to other docs
  doc/RCU/listRCU: Update example function name
  doc/RCU/listRCU: Fix typos in a example code snippets
  doc/RCU/Design: Remove remaining HTML tags in ReST files
  doc: Add some more RCU list patterns in the kernel
  rcutorture: Set KCSAN Kconfig options to detect more data races
  rcutorture: Manually clean up after rcu_barrier() failure
  rcutorture: Make rcu_torture_barrier_cbs() post from corresponding CPU
  rcuperf: Measure memory footprint during kfree_rcu() test
  rcutorture: Annotation lockless accesses to rcu_torture_current
  rcutorture: Add READ_ONCE() to rcu_torture_count and rcu_torture_batch
  rcutorture: Fix stray access to rcu_fwd_cb_nodelay
  rcutorture: Fix rcu_torture_one_read()/rcu_torture_writer() data race
  rcutorture: Make kvm-find-errors.sh abort on bad directory
  ...
2020-03-30 15:52:00 -07:00
Linus Torvalds
6d90508121 ACPI updates for 5.7-rc1
- Update the ACPICA code in the kernel to the 20200214 upstream
    release including:
 
    * Fix to re-enable the sleep button after wakeup (Anchal Agarwal).
    * Fixes for mistakes in comments and typos (Bob Moore).
    * ASL-ASL+ converter updates (Erik Kaneda).
    * Type casting cleanups (Sven Barth).
 
  - Clean up the intialization of the EC driver and eliminate some
    dead code from it (Rafael Wysocki).
 
  - Clean up the quirk tables in the AC and battery drivers (Hans de
    Goede).
 
  - Fix the global lock handling on x86 to ignore unspecified bit
    positions in the global lock field (Jan Engelhardt).
 
  - Add a new "tiny" driver for ACPI button devices exposed by VMs to
    guest kernels to send signals directly to init (Josh Triplett).
 
  - Add a kernel parameter to disable ACPI BGRT on x86 (Alex Hung).
 
  - Make the ACPI PCI host bridge and fan drivers use scnprintf() to
    avoid potential buffer overflows (Takashi Iwai).
 
  - Clean up assorted pieces of code:
 
    * Reorder "asmlinkage" to make g++ happy (Alexey Dobriyan).
    * Drop unneeded variable initialization (Colin Ian King).
    * Add missing __acquires/__releases annotations (Jules Irenge).
    * Replace list_for_each_safe() with list_for_each_entry_safe()
      (chenqiwu).
 -----BEGIN PGP SIGNATURE-----
 
 iQJGBAABCAAwFiEE4fcc61cGeeHD/fCwgsRv/nhiVHEFAl6CCQASHHJqd0Byand5
 c29ja2kubmV0AAoJEILEb/54YlRx15UQAISSZxFTq6huh9c3r0xEgddamhn7VOX+
 phjRuTmPzRn2RqFt7Q/ypiy5qqRgBko7oR0UyMJeHc7YPYcJ2nrRx/6Ymg46nmac
 mdIwTG3y1bH6cD/Fz8cM+9ZCtQl8iZRf36zvlY/8fNpk+Cj98et+x+wbUN8GMO9F
 9anHpPKk7hHCwxSN/SnyrJGJpjKdW057sv9sYwgR65XnM35dGxExQNjqtQVFk/ih
 N7TKVHUAlEE06liS0QYCeugsZsu5/GviU/1uy3qwg+Fxcxw7muHfG/impZwFhdjn
 QrdnFOGz9lFXzY+ynQplW0tJtt1AvOLJzQtzGVOxurTJIgz1pEJnptvDXFWP2YBX
 aESfuFt47bzi/NT1f31L3YQ3vuOJczwkS/QlDxv4TJh6rFdZFnQQNo+iIxBAlB6n
 xSsADFbZ3OaAU2VcjVn6WSL7iD3znnIBZp/xQIybb+9BUoDhSXCTH7rNT7p025cR
 g4KGAevlNDEVKIsZs3UHRQYpFQ+qHDM3WNiAiIEyF9cdenSXEMKrBnEYKSbV7DnI
 rBYexFTvjAyVEb6qnuaQDwHHKhu5Xc0JebIXeTjByg993Y8SFLll7a5d40H71S6Z
 /nG4mOa8+Qt6MqhwvkXLu/cxrXgNmnCG8W9RH0/2sQs25AMys9SESo1jsvEeCS2o
 tC2xCpKl2TlU
 =kQmH
 -----END PGP SIGNATURE-----

Merge tag 'acpi-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI updates from Rafael Wysocki:

   - Update the ACPICA code in the kernel to the 20200214 upstream
     release including:

       * Fix to re-enable the sleep button after wakeup (Anchal
         Agarwal).

       * Fixes for mistakes in comments and typos (Bob Moore).

       * ASL-ASL+ converter updates (Erik Kaneda).

       * Type casting cleanups (Sven Barth).

   - Clean up the intialization of the EC driver and eliminate some dead
     code from it (Rafael Wysocki).

   - Clean up the quirk tables in the AC and battery drivers (Hans de
     Goede).

   - Fix the global lock handling on x86 to ignore unspecified bit
     positions in the global lock field (Jan Engelhardt).

   - Add a new "tiny" driver for ACPI button devices exposed by VMs to
     guest kernels to send signals directly to init (Josh Triplett).

   - Add a kernel parameter to disable ACPI BGRT on x86 (Alex Hung).

   - Make the ACPI PCI host bridge and fan drivers use scnprintf() to
     avoid potential buffer overflows (Takashi Iwai).

   - Clean up assorted pieces of code:

       * Reorder "asmlinkage" to make g++ happy (Alexey Dobriyan).

       * Drop unneeded variable initialization (Colin Ian King).

       * Add missing __acquires/__releases annotations (Jules Irenge).

       * Replace list_for_each_safe() with list_for_each_entry_safe()
         (chenqiwu)"

* tag 'acpi-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (31 commits)
  ACPICA: Update version to 20200214
  ACPI: PCI: Use scnprintf() for avoiding potential buffer overflow
  ACPI: fan: Use scnprintf() for avoiding potential buffer overflow
  ACPI: EC: Eliminate EC_FLAGS_QUERY_HANDSHAKE
  ACPI: EC: Do not clear boot_ec_is_ecdt in acpi_ec_add()
  ACPI: EC: Simplify acpi_ec_ecdt_start() and acpi_ec_init()
  ACPI: EC: Consolidate event handler installation code
  acpi/x86: ignore unspecified bit positions in the ACPI global lock field
  acpi/x86: add a kernel parameter to disable ACPI BGRT
  x86/acpi: make "asmlinkage" part first thing in the function definition
  ACPI: list_for_each_safe() -> list_for_each_entry_safe()
  ACPI: video: remove redundant assignments to variable result
  ACPI: OSL: Add missing __acquires/__releases annotations
  ACPI / battery: Cleanup Lenovo Ideapad Miix 320 DMI table entry
  ACPI / AC: Cleanup DMI quirk table
  ACPI: EC: Use fast path in acpi_ec_add() for DSDT boot EC
  ACPI: EC: Simplify acpi_ec_add()
  ACPI: EC: Drop AE_NOT_FOUND special case from ec_install_handlers()
  ACPI: EC: Avoid passing redundant argument to functions
  ACPI: EC: Avoid printing confusing messages in acpi_ec_setup()
  ...
2020-03-30 15:17:04 -07:00
Linus Torvalds
49835c15a5 Power management updates for 5.7-rc1
- Clean up and rework the PM QoS API to simplify the code and
    reduce the size of it (Rafael Wysocki).
 
  - Fix a suspend-to-idle wakeup regression on Dell XPS13 9370
    and similar platforms where the USB plug/unplug events are
    handled by the EC (Rafael Wysocki).
 
  - CLean up the intel_idle and PSCI cpuidle drivers (Rafael Wysocki,
    Ulf Hansson).
 
  - Extend the haltpoll cpuidle driver so that it can be forced to
    run on some systems where it refused to load (Maciej Szmigiero).
 
  - Convert several cpufreq documents to the .rst format and move the
    legacy driver documentation into one common file (Mauro Carvalho
    Chehab, Rafael Wysocki).
 
  - Update several cpufreq drivers:
 
    * Extend and fix the imx-cpufreq-dt driver (Anson Huang).
 
    * Improve the -EPROBE_DEFER handling and fix unwanted CPU
      overclocking on i.MX6ULL in imx6q-cpufreq (Anson Huang,
      Christoph Niedermaier).
 
    * Add support for Krait based SoCs to the qcom driver (Ansuel
      Smith).
 
    * Add support for OPP_PLUS to ti-cpufreq (Lokesh Vutla).
 
    * Add platform specific intermediate callbacks support to
      cpufreq-dt and update the imx6q driver (Peng Fan).
 
    * Simplify and consolidate some pieces of the intel_pstate driver
      and update its documentation (Rafael Wysocki, Alex Hung).
 
  - Fix several devfreq issues:
 
    * Remove unneeded extern keyword from a devfreq header file
      and use the DEVFREQ_GOV_UPDATE_INTERNAL event name instead of
      DEVFREQ_GOV_INTERNAL (Chanwoo Choi).
 
    * Fix the handling of dev_pm_qos_remove_request() result (Leonard
      Crestez).
 
    * Use constant name for userspace governor (Pierre Kuo).
 
    * Get rid of doc warnings and fix a typo (Christophe JAILLET).
 
  - Use built-in RCU list checking in some places in the PM core to
    avoid false-positive RCU usage warnings (Madhuparna Bhowmik).
 
  - Add explicit READ_ONCE()/WRITE_ONCE() annotations to low-level
    PM QoS routines (Qian Cai).
 
  - Fix removal of wakeup sources to avoid NULL pointer dereferences
    in a corner case (Neeraj Upadhyay).
 
  - Clean up the handling of hibernate compat ioctls and fix the
    related documentation (Eric Biggers).
 
  - Update the idle_inject power capping driver to use variable-length
    arrays instead of zero-length arrays (Gustavo Silva).
 
  - Fix list format in a PM QoS document (Randy Dunlap).
 
  - Make the cpufreq stats module use scnprintf() to avoid potential
    buffer overflows (Takashi Iwai).
 
  - Add pm_runtime_get_if_active() to PM-runtime API (Sakari Ailus).
 
  - Allow no domain-idle-states DT property in generic PM domains (Ulf
    Hansson).
 
  - Fix a broken y-axis scale in the intel_pstate_tracer utility (Doug
    Smythies).
 -----BEGIN PGP SIGNATURE-----
 
 iQJGBAABCAAwFiEE4fcc61cGeeHD/fCwgsRv/nhiVHEFAl6B/YkSHHJqd0Byand5
 c29ja2kubmV0AAoJEILEb/54YlRxEjIP/jXoO1pAxq7BMx7naZnZL7pzemJfAGR7
 HVnRLDo0IlsSwI7Jvuy13a0eI+EcGPA6pRo5qnBM4TZCIFsHoO5Yle47ndNGsi8r
 Jd3T89oT3I+fXI4KTfWO0n+K/F6mv8/CTZDz/E7Z6zirpFxyyZQxgIsAT76RcZom
 xhWna9vygOlBnFsQaAeph+GzoXBWIylaMZfylUeT3v4c4DLH6FzcbnINPkgJsZCw
 Ayt1bmE0L9yiqCizEto91eaDObkxTHVFGr2OVNa/Y/SVW+VUThUJrXqV28opQxPZ
 h4TiQorpTX1CwMmiXZwmoeqqsiVXrm0KyhK0lwc5tZ9FnZWiW4qjJ487Eu6TjOmh
 gecT+M2Yexy0BvUGN0wIdaCLtfmf2Hjxk0trxM2blAh3uoFjf3UJ9SLNkRjlu2/b
 QqWmIRRPljD5fEUid5lVV4EAXuITUzWMJeia+FiAsgx1SF3pZPar80f+FGrYfaJN
 wL2BTwBx1aXpPpAkEX0kM9Rkf6oJsFATR3p7DNzyZ1bMrQUxiToWRlQBID5H6G4v
 /kAkSTQjNQVwkkylUzTLOlcmL56sCvc0YPdybH62OsLXs9K4gyC8v6tEdtdA5qtw
 0Up9DrYbNKKv6GrSXf8eyk2Q2CEqfRXHv2ACNnkLRXZ6fWnFiTfMgNj7zqtrfna7
 tJBvrV9/ACXE
 =cBQd
 -----END PGP SIGNATURE-----

Merge tag 'pm-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management updates from Rafael Wysocki:
 "These clean up and rework the PM QoS API, address a suspend-to-idle
  wakeup regression on some ACPI-based platforms, clean up and extend a
  few cpuidle drivers, update multiple cpufreq drivers and cpufreq
  documentation, and fix a number of issues in devfreq and several other
  things all over.

  Specifics:

   - Clean up and rework the PM QoS API to simplify the code and reduce
     the size of it (Rafael Wysocki).

   - Fix a suspend-to-idle wakeup regression on Dell XPS13 9370 and
     similar platforms where the USB plug/unplug events are handled by
     the EC (Rafael Wysocki).

   - CLean up the intel_idle and PSCI cpuidle drivers (Rafael Wysocki,
     Ulf Hansson).

   - Extend the haltpoll cpuidle driver so that it can be forced to run
     on some systems where it refused to load (Maciej Szmigiero).

   - Convert several cpufreq documents to the .rst format and move the
     legacy driver documentation into one common file (Mauro Carvalho
     Chehab, Rafael Wysocki).

   - Update several cpufreq drivers:

        * Extend and fix the imx-cpufreq-dt driver (Anson Huang).

        * Improve the -EPROBE_DEFER handling and fix unwanted CPU
          overclocking on i.MX6ULL in imx6q-cpufreq (Anson Huang,
          Christoph Niedermaier).

        * Add support for Krait based SoCs to the qcom driver (Ansuel
          Smith).

        * Add support for OPP_PLUS to ti-cpufreq (Lokesh Vutla).

        * Add platform specific intermediate callbacks support to
          cpufreq-dt and update the imx6q driver (Peng Fan).

        * Simplify and consolidate some pieces of the intel_pstate
          driver and update its documentation (Rafael Wysocki, Alex
          Hung).

   - Fix several devfreq issues:

        * Remove unneeded extern keyword from a devfreq header file and
          use the DEVFREQ_GOV_UPDATE_INTERNAL event name instead of
          DEVFREQ_GOV_INTERNAL (Chanwoo Choi).

        * Fix the handling of dev_pm_qos_remove_request() result
          (Leonard Crestez).

        * Use constant name for userspace governor (Pierre Kuo).

        * Get rid of doc warnings and fix a typo (Christophe JAILLET).

   - Use built-in RCU list checking in some places in the PM core to
     avoid false-positive RCU usage warnings (Madhuparna Bhowmik).

   - Add explicit READ_ONCE()/WRITE_ONCE() annotations to low-level PM
     QoS routines (Qian Cai).

   - Fix removal of wakeup sources to avoid NULL pointer dereferences in
     a corner case (Neeraj Upadhyay).

   - Clean up the handling of hibernate compat ioctls and fix the
     related documentation (Eric Biggers).

   - Update the idle_inject power capping driver to use variable-length
     arrays instead of zero-length arrays (Gustavo Silva).

   - Fix list format in a PM QoS document (Randy Dunlap).

   - Make the cpufreq stats module use scnprintf() to avoid potential
     buffer overflows (Takashi Iwai).

   - Add pm_runtime_get_if_active() to PM-runtime API (Sakari Ailus).

   - Allow no domain-idle-states DT property in generic PM domains (Ulf
     Hansson).

   - Fix a broken y-axis scale in the intel_pstate_tracer utility (Doug
     Smythies)"

* tag 'pm-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (78 commits)
  cpufreq: intel_pstate: Simplify intel_pstate_cpu_init()
  tools/power/x86/intel_pstate_tracer: fix a broken y-axis scale
  ACPI: PM: s2idle: Refine active GPEs check
  ACPICA: Allow acpi_any_gpe_status_set() to skip one GPE
  PM: sleep: wakeup: Skip wakeup_source_sysfs_remove() if device is not there
  PM / devfreq: Get rid of some doc warnings
  PM / devfreq: Fix handling dev_pm_qos_remove_request result
  PM / devfreq: Fix a typo in a comment
  PM / devfreq: Change to DEVFREQ_GOV_UPDATE_INTERVAL event name
  PM / devfreq: Remove unneeded extern keyword
  PM / devfreq: Use constant name of userspace governor
  ACPI: PM: s2idle: Fix comment in acpi_s2idle_prepare_late()
  cpufreq: qcom: Add support for krait based socs
  cpufreq: imx6q-cpufreq: Improve the logic of -EPROBE_DEFER handling
  cpufreq: Use scnprintf() for avoiding potential buffer overflow
  cpuidle: psci: Split psci_dt_cpu_init_idle()
  PM / Domains: Allow no domain-idle-states DT property in genpd when parsing
  PM / hibernate: Remove unnecessary compat ioctl overrides
  PM: hibernate: fix docs for ioctls that return loff_t via pointer
  Documentation: intel_pstate: update links for references
  ...
2020-03-30 15:05:01 -07:00
Linus Torvalds
59838093be Driver core patches for 5.7-rc1
Here is the "big" set of driver core changes for 5.7-rc1.
 
 Nothing huge in here, just lots of little firmware core changes and use
 of new apis, a libfs fix, a debugfs api change, and some driver core
 deferred probe rework.
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCXoHLIg8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+yle2ACgjJJzRJl9Ckae3ms+9CS4OSFFZPsAoKSrXmFc
 Z7goYQdZo1zz8c0RYDrJ
 =Y91m
 -----END PGP SIGNATURE-----

Merge tag 'driver-core-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the "big" set of driver core changes for 5.7-rc1.

  Nothing huge in here, just lots of little firmware core changes and
  use of new apis, a libfs fix, a debugfs api change, and some driver
  core deferred probe rework.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'driver-core-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (44 commits)
  Revert "driver core: Set fw_devlink to "permissive" behavior by default"
  driver core: Set fw_devlink to "permissive" behavior by default
  driver core: Replace open-coded list_last_entry()
  driver core: Read atomic counter once in driver_probe_done()
  libfs: fix infoleak in simple_attr_read()
  driver core: Add device links from fwnode only for the primary device
  platform/x86: touchscreen_dmi: Add info for the Chuwi Vi8 Plus tablet
  platform/x86: touchscreen_dmi: Add EFI embedded firmware info support
  Input: icn8505 - Switch to firmware_request_platform for retreiving the fw
  Input: silead - Switch to firmware_request_platform for retreiving the fw
  selftests: firmware: Add firmware_request_platform tests
  test_firmware: add support for firmware_request_platform
  firmware: Add new platform fallback mechanism and firmware_request_platform()
  Revert "drivers: base: power: wakeup.c: Use built-in RCU list checking"
  drivers: base: power: wakeup.c: Use built-in RCU list checking
  component: allow missing unbind callback
  debugfs: remove return value of debugfs_create_file_size()
  debugfs: Check module state before warning in {full/open}_proxy_open()
  firmware: fix a double abort case with fw_load_sysfs_fallback
  arch_topology: Fix putting invalid cpu clk
  ...
2020-03-30 13:59:52 -07:00
Linus Torvalds
481ed297d9 This has been a busy cycle for documentation work. Highlights include:
- Lots of RST conversion work by Mauro, Daniel ALmeida, and others.
     Maybe someday we'll get to the end of this stuff...maybe...
 
   - Some organizational work to bring some order to the core-api manual.
 
   - Various new docs and additions to the existing documentation.
 
   - Typo fixes, warning fixes, ...
 -----BEGIN PGP SIGNATURE-----
 
 iQFDBAABCAAtFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAl6BLf4PHGNvcmJldEBs
 d24ubmV0AAoJEBdDWhNsDH5YLhkIAIhcg6gxp0oZZ3KDfQyhvej0EWQGVDNkmloQ
 O1VOSV3RJsZL9HwN9xSNnNfN5+hw5RUYVbn1s201uj6kovZY9qcTpHP2LCizUeGb
 eFkSTmzkyAuAbJjuVLgMPDerJPEew0HnudiToeSpQeoIL1WB6YGd4/5H/cN1KLex
 8ggjllcY0wOgbiFffmK6+tavDv7vT0lKTdwKRYh2nxu7zrPVVd1ZnW+RtntdTVQt
 i+xwV6/YdWtg5C53IwBPpeyubX40vqaIjU8rzpLq5SCVbsZN14sSR709m1AYCOK0
 i4VDWEhfA2XBi6Nycl5U0czuGziwoHrTgSCkS1mmSDujnpgfKM8=
 =6YOS
 -----END PGP SIGNATURE-----

Merge tag 'docs-5.7' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "This has been a busy cycle for documentation work.

  Highlights include:

   - Lots of RST conversion work by Mauro, Daniel ALmeida, and others.
     Maybe someday we'll get to the end of this stuff...maybe...

   - Some organizational work to bring some order to the core-api
     manual.

   - Various new docs and additions to the existing documentation.

   - Typo fixes, warning fixes, ..."

* tag 'docs-5.7' of git://git.lwn.net/linux: (123 commits)
  Documentation: x86: exception-tables: document CONFIG_BUILDTIME_TABLE_SORT
  MAINTAINERS: adjust to filesystem doc ReST conversion
  docs: deprecated.rst: Add BUG()-family
  doc: zh_CN: add translation for virtiofs
  doc: zh_CN: index files in filesystems subdirectory
  docs: locking: Drop :c:func: throughout
  docs: locking: Add 'need' to hardirq section
  docs: conf.py: avoid thousands of duplicate label warning on Sphinx
  docs: prevent warnings due to autosectionlabel
  docs: fix reference to core-api/namespaces.rst
  docs: fix pointers to io-mapping.rst and io_ordering.rst files
  Documentation: Better document the softlockup_panic sysctl
  docs: hw-vuln: tsx_async_abort.rst: get rid of an unused ref
  docs: perf: imx-ddr.rst: get rid of a warning
  docs: filesystems: fuse.rst: supress a Sphinx warning
  docs: translations: it: avoid duplicate refs at programming-language.rst
  docs: driver.rst: supress two ReSt warnings
  docs: trace: events.rst: convert some new stuff to ReST format
  Documentation: Add io_ordering.rst to driver-api manual
  Documentation: Add io-mapping.rst to driver-api manual
  ...
2020-03-30 12:45:23 -07:00
Rafael J. Wysocki
2409000a0c Merge branches 'pm-devfreq', 'powercap' and 'pm-docs'
* pm-devfreq:
  PM / devfreq: Get rid of some doc warnings
  PM / devfreq: Fix handling dev_pm_qos_remove_request result
  PM / devfreq: Fix a typo in a comment
  PM / devfreq: Change to DEVFREQ_GOV_UPDATE_INTERVAL event name
  PM / devfreq: Remove unneeded extern keyword
  PM / devfreq: Use constant name of userspace governor

* powercap:
  powercap: idle_inject: Replace zero-length array with flexible-array member

* pm-docs:
  docs: cpu-freq: convert cpufreq-stats.txt to ReST
  docs: cpu-freq: convert cpu-drivers.txt to ReST
  docs: cpu-freq: convert core.txt to ReST
  docs: cpu-freq: convert index.txt to ReST
  docs: cpufreq: fix a broken reference
  Documentation: cpufreq: Move legacy driver documentation
2020-03-30 14:48:31 +02:00
Rafael J. Wysocki
0411f0d10e Merge branch 'pm-cpufreq'
* pm-cpufreq:
  cpufreq: intel_pstate: Simplify intel_pstate_cpu_init()
  cpufreq: qcom: Add support for krait based socs
  cpufreq: imx6q-cpufreq: Improve the logic of -EPROBE_DEFER handling
  cpufreq: Use scnprintf() for avoiding potential buffer overflow
  Documentation: intel_pstate: update links for references
  cpufreq: intel_pstate: Consolidate policy verification
  cpufreq: dt: Allow platform specific intermediate callbacks
  cpufreq: imx-cpufreq-dt: Correct i.MX8MP's market segment fuse location
  cpufreq: imx6q: read OCOTP through nvmem for imx6q
  cpufreq: imx6q: fix error handling
  cpufreq: imx-cpufreq-dt: Add "cpu-supply" property check
  cpufreq: ti-cpufreq: Add support for OPP_PLUS
  cpufreq: imx6q: Fixes unwanted cpu overclocking on i.MX6ULL
2020-03-30 14:46:27 +02:00
Rafael J. Wysocki
8f1073ed8c Merge branch 'pm-qos'
* pm-qos: (30 commits)
  PM: QoS: annotate data races in pm_qos_*_value()
  Documentation: power: fix pm_qos_interface.rst format warning
  PM: QoS: Make CPU latency QoS depend on CONFIG_CPU_IDLE
  Documentation: PM: QoS: Update to reflect previous code changes
  PM: QoS: Update file information comments
  PM: QoS: Drop PM_QOS_CPU_DMA_LATENCY and rename related functions
  sound: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: usb: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: tty: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: spi: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: net: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: mmc: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: media: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: hsi: Call cpu_latency_qos_*() instead of pm_qos_*()
  drm: i915: Call cpu_latency_qos_*() instead of pm_qos_*()
  x86: platform: iosf_mbi: Call cpu_latency_qos_*() instead of pm_qos_*()
  cpuidle: Call cpu_latency_qos_limit() instead of pm_qos_request()
  PM: QoS: Add CPU latency QoS API wrappers
  PM: QoS: Adjust pm_qos_request() signature and reorder pm_qos.h
  PM: QoS: Simplify definitions of CPU latency QoS trace events
  ...
2020-03-30 14:45:57 +02:00
Konstantin Khlebnikov
2b8bd42361 block/diskstats: more accurate approximation of io_ticks for slow disks
Currently io_ticks is approximated by adding one at each start and end of
requests if jiffies counter has changed. This works perfectly for requests
shorter than a jiffy or if one of requests starts/ends at each jiffy.

If disk executes just one request at a time and they are longer than two
jiffies then only first and last jiffies will be accounted.

Fix is simple: at the end of request add up into io_ticks jiffies passed
since last update rather than just one jiffy.

Example: common HDD executes random read 4k requests around 12ms.

fio --name=test --filename=/dev/sdb --rw=randread --direct=1 --runtime=30 &
iostat -x 10 sdb

Note changes of iostat's "%util" 8,43% -> 99,99% before/after patch:

Before:

Device:         rrqm/s   wrqm/s     r/s     w/s    rkB/s    wkB/s avgrq-sz avgqu-sz   await r_await w_await  svctm  %util
sdb               0,00     0,00   82,60    0,00   330,40     0,00     8,00     0,96   12,09   12,09    0,00   1,02   8,43

After:

Device:         rrqm/s   wrqm/s     r/s     w/s    rkB/s    wkB/s avgrq-sz avgqu-sz   await r_await w_await  svctm  %util
sdb               0,00     0,00   82,50    0,00   330,00     0,00     8,00     1,00   12,10   12,10    0,00  12,12  99,99

Now io_ticks does not loose time between start and end of requests, but
for queue-depth > 1 some I/O time between adjacent starts might be lost.

For load estimation "%util" is not as useful as average queue length,
but it clearly shows how often disk queue is completely empty.

Fixes: 5b18b5a737 ("block: delete part_round_stats and switch to less precise counting")
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-25 08:49:08 -06:00
Ingo Molnar
baf5fe7618 Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU changes from Paul E. McKenney:

 - Make kfree_rcu() use kfree_bulk() for added performance
 - RCU updates
 - Callback-overload handling updates
 - Tasks-RCU KCSAN and sparse updates
 - Locking torture test and RCU torture test updates
 - Documentation updates
 - Miscellaneous fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-24 10:10:09 +01:00
Alexey Makhalov
e73a8f38f8 x86/vmware: Enable steal time accounting
Set paravirt_steal_rq_enabled if steal clock present.
paravirt_steal_rq_enabled is used in sched/core.c to adjust task
progress by offsetting stolen time. Use 'no-steal-acc' off switch (share
same name with KVM) to disable steal time accounting.

Signed-off-by: Alexey Makhalov <amakhalov@vmware.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200323195707.31242-5-amakhalov@vmware.com
2020-03-24 10:06:27 +01:00
Paul E. McKenney
aa93ec620b Merge branches 'doc.2020.02.27a', 'fixes.2020.03.21a', 'kfree_rcu.2020.02.20a', 'locktorture.2020.02.20a', 'ovld.2020.02.20a', 'rcu-tasks.2020.02.20a', 'srcu.2020.02.20a' and 'torture.2020.02.20a' into HEAD
doc.2020.02.27a: Documentation updates.
fixes.2020.03.21a: Miscellaneous fixes.
kfree_rcu.2020.02.20a: Updates to kfree_rcu().
locktorture.2020.02.20a: Lock torture-test updates.
ovld.2020.02.20a: Updates to callback-overload handling.
rcu-tasks.2020.02.20a: RCU-tasks updates.
srcu.2020.02.20a: SRCU updates.
torture.2020.02.20a: Torture-test updates.
2020-03-21 17:15:11 -07:00
Romuald Brunet
a7d47e59e7 docs: Add reference in binfmt-misc.rst
While looking at the binfmt-misc documentation I noticed that there is a
reference to the “java” example that could be a direct link.

This patch simply adds the link without changing the HTML output.

Signed-off-by: Romuald Brunet <romuald@chivil.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2020-03-17 20:41:00 +01:00
Alex Hung
c1f59a3782 Documentation: intel_pstate: update links for references
URLs for presentation and Intel Software Developer’s Manual are updated
as they were using "http" which are gradually replaced by "https".

Signed-off-by: Alex Hung <alex.hung@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-14 11:46:02 +01:00
Alex Hung
1ffb8d032d acpi/x86: add a kernel parameter to disable ACPI BGRT
BGRT is for displaying seamless OEM logo from booting to login screen;
however, this mechanism does not always work well on all configurations
and the OEM logo can be displayed multiple times. This looks worse than
without BGRT enabled.

This patch adds a kernel parameter to disable BGRT in boot time. This is
easier than re-compiling a kernel with CONFIG_ACPI_BGRT disabled.

Signed-off-by: Alex Hung <alex.hung@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-14 10:36:49 +01:00
David S. Miller
44ef976ab3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2020-03-13

The following pull-request contains BPF updates for your *net-next* tree.

We've added 86 non-merge commits during the last 12 day(s) which contain
a total of 107 files changed, 5771 insertions(+), 1700 deletions(-).

The main changes are:

1) Add modify_return attach type which allows to attach to a function via
   BPF trampoline and is run after the fentry and before the fexit programs
   and can pass a return code to the original caller, from KP Singh.

2) Generalize BPF's kallsyms handling and add BPF trampoline and dispatcher
   objects to be visible in /proc/kallsyms so they can be annotated in
   stack traces, from Jiri Olsa.

3) Extend BPF sockmap to allow for UDP next to existing TCP support in order
   in order to enable this for BPF based socket dispatch, from Lorenz Bauer.

4) Introduce a new bpftool 'prog profile' command which attaches to existing
   BPF programs via fentry and fexit hooks and reads out hardware counters
   during that period, from Song Liu. Example usage:

   bpftool prog profile id 337 duration 3 cycles instructions llc_misses

        4228 run_cnt
     3403698 cycles                                              (84.08%)
     3525294 instructions   #  1.04 insn per cycle               (84.05%)
          13 llc_misses     #  3.69 LLC misses per million isns  (83.50%)

5) Batch of improvements to libbpf, bpftool and BPF selftests. Also addition
   of a new bpf_link abstraction to keep in particular BPF tracing programs
   attached even when the applicaion owning them exits, from Andrii Nakryiko.

6) New bpf_get_current_pid_tgid() helper for tracing to perform PID filtering
   and which returns the PID as seen by the init namespace, from Carlos Neira.

7) Refactor of RISC-V JIT code to move out common pieces and addition of a
   new RV32G BPF JIT compiler, from Luke Nelson.

8) Add gso_size context member to __sk_buff in order to be able to know whether
   a given skb is GSO or not, from Willem de Bruijn.

9) Add a new bpf_xdp_output() helper which reuses XDP's existing perf RB output
   implementation but can be called from tracepoint programs, from Eelco Chaudron.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-13 20:52:03 -07:00
Guilherme G. Piccoli
0a07bef6e5 Documentation: Better document the softlockup_panic sysctl
Commit 9c44bc03ff ("softlockup: allow panic on lockup") added the
softlockup_panic sysctl, but didn't add information about it to the file
Documentation/admin-guide/sysctl/kernel.rst (which in that time certainly
wasn't rst and had other name!).

This patch just adds the respective documentation and references it from
the corresponding entry in Documentation/admin-guide/kernel-parameters.txt.

This patch was strongly based on Scott Wood's commit d22881dc13
("Documentation: Better document the hardlockup_panic sysctl").

Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Guilherme G. Piccoli <gpiccoli@canonical.com>
Link: https://lore.kernel.org/r/20200310183649.23163-1-gpiccoli@canonical.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-03-10 13:55:55 -06:00
Mauro Carvalho Chehab
23f03fe220 docs: hw-vuln: tsx_async_abort.rst: get rid of an unused ref
The virt_mechanism reference there points to a section
called elsewhere (Virtualization mitigation). Also, it is
not used anywere.

Besides that, it conflicts with a label with the same name
inside:

	Documentation/admin-guide/hw-vuln/mds.rst

Perhaps added due to some cut-and-paste?

Anyway, as this is not used, let's just get rid of it.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/681c8e2916bf4943ac2277f181668bfbc5fdbc01.1583250595.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-03-10 11:56:48 -06:00
Mauro Carvalho Chehab
2b008dc692 docs: perf: imx-ddr.rst: get rid of a warning
Documentation/admin-guide/perf/imx-ddr.rst:47: WARNING: Unexpected indentation.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/b27b54bd4f847032fd33313d6497ff320c0f3d78.1583250595.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-03-10 11:56:15 -06:00
Jonathan Neuschäfer
ea6b537083 docs: admin-guide: binfmt-misc: Improve the title
Trim the title a bit, since it's relatively long. Add `binfmt_misc` to
make it easier to search for the feature by its common name.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Link: https://lore.kernel.org/r/20200308210935.7273-1-j.neuschaefer@gmx.net
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-03-10 11:13:24 -06:00
Greg Kroah-Hartman
9a2dd57059 Merge 5.6-rc5 into driver-core-next
We need the driver core and debugfs changes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-09 08:41:53 +01:00
Greg Kroah-Hartman
bb3a151dd4 Merge 5.6-rc5 into char-misc-next
We need the binder and other fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-09 08:38:58 +01:00
Thara Gopinath
05289b90c2 sched/fair: Enable tuning of decay period
Thermal pressure follows pelt signals which means the decay period for
thermal pressure is the default pelt decay period. Depending on SoC
characteristics and thermal activity, it might be beneficial to decay
thermal pressure slower, but still in-tune with the pelt signals.  One way
to achieve this is to provide a command line parameter to set a decay
shift parameter to an integer between 0 and 10.

Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200222005213.3873-10-thara.gopinath@linaro.org
2020-03-06 12:57:21 +01:00
Rafael J. Wysocki
86dfa5bec2 Merge branch 'acpi-doc'
* acpi-doc:
  Documentation/admin-guide/acpi: fix fan_performance_states.rst warnings
2020-03-06 10:57:46 +01:00
Luke Nelson
06b7415216 bpf, doc: Add BPF JIT for RV32G to BPF documentation
Update filter.txt and admin-guide to mention the BPF JIT for RV32G.

Co-developed-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Luke Nelson <luke.r.nels@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Björn Töpel <bjorn.topel@gmail.com>
Acked-by: Björn Töpel <bjorn.topel@gmail.com>
Link: https://lore.kernel.org/bpf/20200305050207.4159-4-luke.r.nels@gmail.com
2020-03-05 16:13:47 +01:00
Saravana Kannan
e94f62b714 of: property: Delete of_devlink kernel commandline option
With the addition of fw_devlink kernel commandline option, of_devlink is
redundant and not useful anymore. So, delete it.

Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200222014038.180923-6-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-04 17:58:48 +01:00
Saravana Kannan
8375e74f2b driver core: Add fw_devlink kernel commandline option
fwnode_operations.add_links allows creating device links from
information provided by firmware.

fwnode_operations.add_links is currently implemented only by
OF/devicetree code and a specific case of efi. However, there's nothing
preventing ACPI or other firmware types from implementing it.

The OF implementation is currently controlled by a kernel commandline
parameter called of_devlink.

Since this feature is generic isn't limited to OF, add a generic
fw_devlink kernel commandline parameter to control this feature across
firmware types.

Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20200222014038.180923-3-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-04 17:58:48 +01:00
Niklas Söderlund
3eb30c51a6 Documentation: nfsroot.rst: Fix references to nfsroot.rst
When converting and moving nfsroot.txt to nfsroot.rst the references to
the old text file was not updated to match the change, fix this.

Fixes: f9a9349846 ("Documentation: nfsroot.txt: convert to ReST")
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200212181332.520545-1-niklas.soderlund+renesas@ragnatech.se
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-03-02 13:11:46 -07:00
Zenghui Yu
ae5977765a Documentation: kthread: Fix WQ_SYSFS workqueues path name
The set of WQ_SYSFS workqueues should be displayed using
"ls /sys/devices/virtual/workqueue", add the missing '/'.

Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20200225124052.1506-1-yuzenghui@huawei.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-03-02 13:04:57 -07:00
Jakub Kicinski
373e8ffafd doc: cgroup: improve formatting of references
Annotate references to other documents to make them clickable.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/r/20200228000653.1572553-6-kuba@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-03-02 12:57:03 -07:00
Jakub Kicinski
f3431ba715 doc: cgroup: improve formatting of cpuset examples
We need literal sections otherwise the entire example is rendered
as a single line.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/r/20200228000653.1572553-5-kuba@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-03-02 12:57:03 -07:00
Jakub Kicinski
69654d37cf doc: cgroup: improve formatting of io example
We need a literal section, like few paragraphs below.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/r/20200228000653.1572553-4-kuba@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-03-02 12:57:03 -07:00
Jakub Kicinski
2551cab599 doc: cgroup: improve formatting of mem stats
If there is an empty line between item and description
Sphinx does not emphasize the item. First half of the
list does not have the empty line and is emphasized
correctly.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/r/20200228000653.1572553-3-kuba@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-03-02 12:57:03 -07:00
Jakub Kicinski
d0c3bacb3e doc: cgroup: improve formatting
Fix tabs vs spaces issue which cases the line to be considered
a new list entry.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/r/20200228000653.1572553-2-kuba@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-03-02 12:57:03 -07:00
Jonathan Neuschäfer
7fe068dba8 docs: admin-guide: kernel-parameters: Document earlycon options for i.MX UARTs
drivers/tty/serial/imx.c implements these earlycon options.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Link: https://lore.kernel.org/r/20200229132750.2783-1-j.neuschaefer@gmx.net
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-03-02 12:51:37 -07:00
Rafael J. Wysocki
03b2249650 Documentation: cpufreq: Move legacy driver documentation
There are three legacy driver documents in Documentation/cpu-freq/
that were added years ago and converting them each to the .rst
format is rather pointless, even though there is some value in
preserving them.  However, if they are preserved, they need to go
into the admin-guide part of cpufreq documentation where they belong
(at least to a certain extent).

To preserve them with minimum amount of changes and put them into the
right place, and make it possible to process them into HTML (and other
formats) along with the rest of the documentation, move them each
as a "literal text" block into a separate section of a single .rst
"wrapper" file under Documentation/admin-guide/pm/.

While at it, repair the PCC specification URL in one of them.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-02 11:31:06 +01:00
Linus Torvalds
c60c040213 ACPI fixes for 5.6-rc4
Fix a couple of configuration issues in the ACPI watchdog (WDAT)
 driver (Mika Westerberg) and make it possible to disable that
 driver at boot time in case it still does not work as
 expected (Jean Delvare).
 -----BEGIN PGP SIGNATURE-----
 
 iQJGBAABCAAwFiEE4fcc61cGeeHD/fCwgsRv/nhiVHEFAl5Y6UYSHHJqd0Byand5
 c29ja2kubmV0AAoJEILEb/54YlRxj7YP/1qVMcIJo3CcItiQVV7+2S+WS+kK+Rf8
 t6g+8F5KL0DBrDqji7l19kv0O+kPpn2uGnREcNk3T3mHEu0jSywghvBI+nzrym2P
 Q+p2+2Fryy5zgiNTyhq7imA3IH4Zw5CVt6GRJjITvzFwhMGM38NQsDUbZEpZtJrz
 HTVQyqPgmhvox5sa2Qk1+vZOtclWlkPenWmtJEs8m+Pg8w+Ejfs4Lj+CQYlI5RB8
 GGhTgBiBMS7A80yTVxl8LULsrini6PWAGGY2yMScwDUYNZTAUuT8QSUx4/QBmyyP
 U5K1sIK2pd/JuE2QqSBztrYC7x1fpfoBJylF8B0HK5uNBpZth7eXhe6t+xDYVTpw
 U31unYfmcx6UT47lF/yWWNuhP6EDvdvZ0Xx4DHlgBJqKNuyfhz4Uazsr7HyLi2sI
 /YrBPimtgvICFHYorrNVwEheTUEp+QXtNZp6aTugLGVX6zbQ3nZp7ajifNO7hdsQ
 K+IjjRgH/YsVi9GQY/U3A/zTO+39fSupQgKiH33pG8Yp5bZbreoo1kPKzlnt23JJ
 DXuaN7wH74sgT2EqZm30lFapF/0wv+iIpdWmorlE/4WwTwIeDck/ULeBiGFqpUI6
 9Di10O6w+TJ+VevyJ5Hqkzukjlj93Vq+kCY8eOiWVpTga2ieQiYKFSbxDPE3OC1k
 j2wkDwKqkh0o
 =eIlw
 -----END PGP SIGNATURE-----

Merge tag 'acpi-5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI fixes from Rafael Wysocki:
 "Fix a couple of configuration issues in the ACPI watchdog (WDAT)
  driver (Mika Westerberg) and make it possible to disable that driver
  at boot time in case it still does not work as expected (Jean
  Delvare)"

* tag 'acpi-5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: watchdog: Set default timeout in probe
  ACPI: watchdog: Fix gas->access_width usage
  ACPICA: Introduce ACPI_ACCESS_BYTE_WIDTH() macro
  ACPI: watchdog: Allow disabling WDAT at boot
2020-02-28 09:02:18 -08:00
Vasily Gorbik
ecdc5d842b s390/protvirt: introduce host side setup
Add "prot_virt" command line option which controls if the kernel
protected VMs support is enabled at early boot time. This has to be
done early, because it needs large amounts of memory and will disable
some features like STP time sync for the lpar.

Extend ultravisor info definitions and expose it via uv_info struct
filled in during startup.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2020-02-27 19:44:40 +01:00
Linus Torvalds
91ad64a84e Tracing updates:
Change in API of bootconfig (before it comes live in a release)
   - Have a magic value "BOOTCONFIG" in initrd to know a bootconfig exists
   - Set CONFIG_BOOT_CONFIG to 'n' by default
   - Show error if "bootconfig" on cmdline but not compiled in
   - Prevent redefining the same value
   - Have a way to append values
   - Added a SELECT BLK_DEV_INITRD to fix a build failure
 
  Synthetic event fixes:
   - Switch to raw_smp_processor_id() for recording CPU value in preempt
     section. (No care for what the value actually is)
   - Fix samples always recording u64 values
   - Fix endianess
   - Check number of values matches number of fields
   - Fix a printing bug
 
  Fix of trace_printk() breaking postponed start up tests
 
  Make a function static that is only used in a single file.
 -----BEGIN PGP SIGNATURE-----
 
 iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXlW4vxQccm9zdGVkdEBn
 b29kbWlzLm9yZwAKCRAp5XQQmuv6qtioAP0WLEm3dWO0z3321h/a0DSshC+Bslu3
 HDPTsGVGrXmvggEA/lr1ikRHd8PsO7zW8BfaZMxoXaTqXiuSrzEWxnMlFw0=
 =O8PM
 -----END PGP SIGNATURE-----

Merge tag 'trace-v5.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing and bootconfig updates:
 "Fixes and changes to bootconfig before it goes live in a release.

  Change in API of bootconfig (before it comes live in a release):
  - Have a magic value "BOOTCONFIG" in initrd to know a bootconfig
    exists
  - Set CONFIG_BOOT_CONFIG to 'n' by default
  - Show error if "bootconfig" on cmdline but not compiled in
  - Prevent redefining the same value
  - Have a way to append values
  - Added a SELECT BLK_DEV_INITRD to fix a build failure

  Synthetic event fixes:
  - Switch to raw_smp_processor_id() for recording CPU value in preempt
    section. (No care for what the value actually is)
  - Fix samples always recording u64 values
  - Fix endianess
  - Check number of values matches number of fields
  - Fix a printing bug

  Fix of trace_printk() breaking postponed start up tests

  Make a function static that is only used in a single file"

* tag 'trace-v5.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  bootconfig: Fix CONFIG_BOOTTIME_TRACING dependency issue
  bootconfig: Add append value operator support
  bootconfig: Prohibit re-defining value on same key
  bootconfig: Print array as multiple commands for legacy command line
  bootconfig: Reject subkey and value on same parent key
  tools/bootconfig: Remove unneeded error message silencer
  bootconfig: Add bootconfig magic word for indicating bootconfig explicitly
  bootconfig: Set CONFIG_BOOT_CONFIG=n by default
  tracing: Clear trace_state when starting trace
  bootconfig: Mark boot_config_checksum() static
  tracing: Disable trace_printk() on post poned tests
  tracing: Have synthetic event test use raw_smp_processor_id()
  tracing: Fix number printing bug in print_synth_event()
  tracing: Check that number of vals matches number of synth event fields
  tracing: Make synth_event trace functions endian-correct
  tracing: Make sure synth_event_trace() example always uses u64
2020-02-26 10:34:42 -08:00
Stephen Kitt
021622df55 docs: add a script to check sysctl docs
This script allows sysctl documentation to be checked against the
kernel source code, to identify missing or obsolete entries. Running
it against 5.5 shows for example that sysctl/kernel.rst has two
obsolete entries and is missing 52 entries.

Signed-off-by: Stephen Kitt <steve@sk2.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-02-25 03:35:16 -07:00
Alex Hung
bf347b9da9 Documentation: fix a typo for intel_iommu=nobounce
"untrusted" was mis-spelled as "unstrusted"

Signed-off-by: Alex Hung <alex.hung@canonical.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-02-25 03:34:25 -07:00
Stephen Kitt
2bd49cb581 docs: sysctl/kernel: document acpi_video_flags
Based on the implementation in arch/x86/kernel/acpi/sleep.c, in
particular the acpi_sleep_setup() function.

Signed-off-by: Stephen Kitt <steve@sk2.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-02-25 03:27:23 -07:00
Masami Hiramatsu
5f811c57c9 bootconfig: Add append value operator support
Add append value operator "+=" support to bootconfig syntax.
With this operator, user can add new value to the key as
an entry of array instead of overwriting.
For example,

  foo = bar
  ...
  foo += baz

Then the key "foo" has "bar" and "baz" values as an array.

Link: http://lkml.kernel.org/r/158227283195.12842.8310503105963275584.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-21 09:59:39 -05:00
Masami Hiramatsu
4e4694d872 bootconfig: Prohibit re-defining value on same key
Currently, bootconfig adds a new value on the existing key to the tail of an
array. But this looks a bit confusing because an admin can easily rewrite
the original value in the same config file.

This rejects the following value re-definition.

  key = value1
  ...
  key = value2

You should rewrite value1 to value2 in this case.

Link: http://lkml.kernel.org/r/158227282199.12842.10110929876059658601.stgit@devnote2

Suggested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
[ Fixed spelling of arraies to arrays ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-21 09:59:19 -05:00
Paul E. McKenney
8171d3e0da torture: Allow disabling of boottime CPU-hotplug torture operations
In theory, RCU-hotplug operations are supposed to work as soon as there
is more than one CPU online.  However, in practice, in normal production
there is no way to make them happen until userspace is up and running.
Besides which, on smaller systems, rcutorture doesn't start doing hotplug
operations until 30 seconds after the start of boot, which on most
systems also means the better part of 30 seconds after the end of boot.
This commit therefore provides a new torture.disable_onoff_at_boot kernel
boot parameter that suppresses CPU-hotplug torture operations until
about the time that init is spawned.

Of course, if you know of a need for boottime CPU-hotplug operations,
then you should avoid passing this argument to any of the torture tests.
You might also want to look at the splats linked to below.

Link: https://lore.kernel.org/lkml/20191206185208.GA25636@paulmck-ThinkPad-P72/
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-02-20 16:03:30 -08:00
Paul E. McKenney
58c53360b3 rcutorture: Allow boottime stall warnings to be suppressed
In normal production, an RCU CPU stall warning at boottime is often
just as bad as at any other time.  In fact, given the desire for fast
boot, any sort of long-term stall at boot is a bad idea.  However,
heavy rcutorture testing on large hyperthreaded systems can generate
boottime RCU CPU stalls as a matter of course.  This commit therefore
provides a kernel boot parameter that suppresses reporting of boottime
RCU CPU stall warnings and similarly of rcutorture writer stalls.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-02-20 16:03:30 -08:00
Paul E. McKenney
b2b00ddf19 rcu: React to callback overload by aggressively seeking quiescent states
In default configutions, RCU currently waits at least 100 milliseconds
before asking cond_resched() and/or resched_rcu() for help seeking
quiescent states to end a grace period.  But 100 milliseconds can be
one good long time during an RCU callback flood, for example, as can
happen when user processes repeatedly open and close files in a tight
loop.  These 100-millisecond gaps in successive grace periods during a
callback flood can result in excessive numbers of callbacks piling up,
unnecessarily increasing memory footprint.

This commit therefore asks cond_resched() and/or resched_rcu() for help
as early as the first FQS scan when at least one of the CPUs has more
than 20,000 callbacks queued, a number that can be changed using the new
rcutree.qovld kernel boot parameter.  An auxiliary qovld_calc variable
is used to avoid acquisition of locks that have not yet been initialized.
Early tests indicate that this reduces the RCU-callback memory footprint
during rcutorture floods by from 50% to 4x, depending on configuration.

Reported-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Reported-by: Tejun Heo <tj@kernel.org>
[ paulmck: Fix bug located by Qian Cai. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Tested-by: Dexuan Cui <decui@microsoft.com>
Tested-by: Qian Cai <cai@lca.pw>
2020-02-20 16:00:20 -08:00
Masami Hiramatsu
a24d286f36 bootconfig: Reject subkey and value on same parent key
Reject if a value node is mixed with subkey node on same
parent key node.

A value node can not co-exist with subkey node under some key
node, e.g.

key = value
key.subkey = another-value

This is not be allowed because bootconfig API is not designed
to handle such case.

Link: http://lkml.kernel.org/r/158220115232.26565.7792340045009731803.stgit@devnote2

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-20 17:54:09 -05:00
Masami Hiramatsu
85c46b78da bootconfig: Add bootconfig magic word for indicating bootconfig explicitly
Add bootconfig magic word to the end of bootconfig on initrd
image for indicating explicitly the bootconfig is there.
Also tools/bootconfig treats wrong size or wrong checksum or
parse error as an error, because if there is a bootconfig magic
word, there must be a bootconfig.

The bootconfig magic word is "#BOOTCONFIG\n", 12 bytes word.
Thus the block image of the initrd file with bootconfig is
as follows.

[Initrd][bootconfig][size][csum][#BOOTCONFIG\n]

Link: http://lkml.kernel.org/r/158220112263.26565.3944814205960612841.stgit@devnote2

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-20 17:52:34 -05:00
Peter Zijlstra (Intel)
6650cdd9a8 x86/split_lock: Enable split lock detection by kernel
A split-lock occurs when an atomic instruction operates on data that spans
two cache lines. In order to maintain atomicity the core takes a global bus
lock.

This is typically >1000 cycles slower than an atomic operation within a
cache line. It also disrupts performance on other cores (which must wait
for the bus lock to be released before their memory operations can
complete). For real-time systems this may mean missing deadlines. For other
systems it may just be very annoying.

Some CPUs have the capability to raise an #AC trap when a split lock is
attempted.

Provide a command line option to give the user choices on how to handle
this:

split_lock_detect=
	off	- not enabled (no traps for split locks)
	warn	- warn once when an application does a
		  split lock, but allow it to continue
		  running.
	fatal	- Send SIGBUS to applications that cause split lock

On systems that support split lock detection the default is "warn". Note
that if the kernel hits a split lock in any mode other than "off" it will
OOPs.

One implementation wrinkle is that the MSR to control the split lock
detection is per-core, not per thread. This might result in some short
lived races on HT systems in "warn" mode if Linux tries to enable on one
thread while disabling on the other. Race analysis by Sean Christopherson:

  - Toggling of split-lock is only done in "warn" mode.  Worst case
    scenario of a race is that a misbehaving task will generate multiple
    #AC exceptions on the same instruction.  And this race will only occur
    if both siblings are running tasks that generate split-lock #ACs, e.g.
    a race where sibling threads are writing different values will only
    occur if CPUx is disabling split-lock after an #AC and CPUy is
    re-enabling split-lock after *its* previous task generated an #AC.
  - Transitioning between off/warn/fatal modes at runtime isn't supported
    and disabling is tracked per task, so hardware will always reach a steady
    state that matches the configured mode.  I.e. split-lock is guaranteed to
    be enabled in hardware once all _TIF_SLD threads have been scheduled out.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Co-developed-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Co-developed-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20200126200535.GB30377@agluck-desk2.amr.corp.intel.com
2020-02-20 21:17:53 +01:00
Randy Dunlap
ae99fb8baa Documentation/admin-guide/acpi: fix fan_performance_states.rst warnings
Fix Sphinx format warnings in fan_performace_states.rst
by adding indentation.

Documentation/admin-guide/acpi/fan_performance_states.rst:21: WARNING: Literal block ends without a blank line; unexpected unindent.
Documentation/admin-guide/acpi/fan_performance_states.rst:41: WARNING: Literal block expected; none found.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-02-20 10:50:43 +01:00
Jonathan Neuschäfer
b4ce545f34 docs: admin-guide: edid: Clarify where to run "make"
When both the documentation and the data files lived in
Documentation/EDID, this wasn't necessary, but both have
been moved to other directories in the meantime.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-02-19 04:10:32 -07:00
Jonathan Neuschäfer
320bfd91a9 docs: admin-guide: Move edid.rst from driver-api
This document describes actions that an admin can do, rather than
interfaces available to driver developers, so admin-guide seems to
be a more appropriate place for it.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-02-19 04:10:31 -07:00
Stephen Kitt
8f21f54b8a docs: sysctl/kernel: remove rtsig entries
These have no corresponding code in the kernel.

Signed-off-by: Stephen Kitt <steve@sk2.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-02-19 03:34:42 -07:00