Commit Graph

590841 Commits

Author SHA1 Message Date
Chen Yu
886123fb3a x86/tsc: Read all ratio bits from MSR_PLATFORM_INFO
Currently we read the tsc radio: ratio = (MSR_PLATFORM_INFO >> 8) & 0x1f;

Thus we get bit 8-12 of MSR_PLATFORM_INFO, however according to the SDM
(35.5), the ratio bits are bit 8-15.

Ignoring the upper bits can result in an incorrect tsc ratio, which causes the
TSC calibration and the Local APIC timer frequency to be incorrect.

Fix this problem by masking 0xff instead.

[ tglx: Massaged changelog ]

Fixes: 7da7c15613 "x86, tsc: Add static (MSR) TSC calibration on Intel Atom SoCs"
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: stable@vger.kernel.org
Cc: Bin Gao <bin.gao@intel.com>
Cc: Len Brown <lenb@kernel.org>
Link: http://lkml.kernel.org/r/1462505619-5516-1-git-send-email-yu.c.chen@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-05-06 11:50:50 +02:00
Yinghai Lu
9dc1969c24 x86/KASLR: Consolidate mem_avoid[] entries
The mem_avoid[] array is used to track positions that should be avoided (like
the compressed kernel, decompression code, etc) when selecting a memory
position for the randomly relocated kernel. Since ZO is now at the end of
the decompression buffer and the decompression code (and its heap and
stack) are at the front, we can safely consolidate the decompression entry,
the heap entry, and the stack entry. The boot_params memory, however, could
be elsewhere, so it should be explicitly included.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Baoquan He <bhe@redhat.com>
[ Rwrote changelog, cleaned up code comments. ]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: kernel-hardening@lists.openwall.com
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1462486436-3707-3-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-06 09:00:59 +02:00
Kees Cook
2bc1cd39fa x86/boot: Clean up pointer casting
Currently extract_kernel() defines the input and output buffer pointers
as "unsigned char *" since that's effectively what they are. It passes
these to the decompressor routine and to the ELF parser, which both
logically deal with buffer pointers too. There is some casting ("unsigned
long") done to validate the numerical value of the pointers, but it is
relatively limited.

However, choose_random_location() operates almost exclusively on the
numerical representation of these pointers, so it ended up carrying
a lot of "unsigned long" casts. With the future physical/virtual split
these casts were going to multiply, so this attempts to solve the
problem by doing all the casting in choose_random_location()'s entry
and return instead of through-out the code. Adjusts argument names to
be more meaningful, and changes one us of "choice" to "output" to make
the future physical/virtual split more clear (i.e. "choice" should be
strictly a function return value and not used as an intermediate).

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: kernel-hardening@lists.openwall.com
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1462486436-3707-2-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-06 09:00:59 +02:00
Ingo Molnar
c0edb7467c perf/core improvements and fixes:
User visible:
 
 - Order output of 'perf trace --summary' better, now the threads will
   appear ascending order of number of events, and then, for each, in
   descending order of syscalls by the time spent in the syscalls, so
   that the last page produced can be the one about the most interesting
   thread straced, suggested by Milian Wolff (Arnaldo Carvalho de Melo)
 
 - Do not show the runtime_ms for a thread when not collecting it, that
   is done so far only with 'perf trace --sched' (Arnaldo Carvalho de Melo)
 
 - Fix kallsyms perf test on ppc64le (Naveen N. Rao)
 
 Infrastructure:
 
 - Move global variables related to presence of some keys in the sort order to a
   per hist struct, to allow code like the hists browser to work with multiple
   hists with different lists of columns (Jiri Olsa)
 
 - Add support for generating bpf prologue in powerpc (Naveen N. Rao)
 
 - Fix kprobe and kretprobe handling with kallsyms on ppc64le (Naveen N. Rao)
 
 - evlist mmap changes, prep work for supporting reading backwards (Wang Nan)
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-core-for-mingo-20160505' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

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

User visible changes:

- Order output of 'perf trace --summary' better, now the threads will
  appear ascending order of number of events, and then, for each, in
  descending order of syscalls by the time spent in the syscalls, so
  that the last page produced can be the one about the most interesting
  thread straced, suggested by Milian Wolff (Arnaldo Carvalho de Melo)

- Do not show the runtime_ms for a thread when not collecting it, that
  is done so far only with 'perf trace --sched' (Arnaldo Carvalho de Melo)

- Fix kallsyms perf test on ppc64le (Naveen N. Rao)

Infrastructure changes:

- Move global variables related to presence of some keys in the sort order to a
  per hist struct, to allow code like the hists browser to work with multiple
  hists with different lists of columns (Jiri Olsa)

- Add support for generating bpf prologue in powerpc (Naveen N. Rao)

- Fix kprobe and kretprobe handling with kallsyms on ppc64le (Naveen N. Rao)

- evlist mmap changes, prep work for supporting reading backwards (Wang Nan)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-06 08:35:14 +02:00
Linus Torvalds
9caa7e7848 Merge branch 'akpm' (patches from Andrew)
Merge fixes from Andrew Morton:
 "14 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  byteswap: try to avoid __builtin_constant_p gcc bug
  lib/stackdepot: avoid to return 0 handle
  mm: fix kcompactd hang during memory offlining
  modpost: fix module autoloading for OF devices with generic compatible property
  proc: prevent accessing /proc/<PID>/environ until it's ready
  mm/zswap: provide unique zpool name
  mm: thp: kvm: fix memory corruption in KVM with THP enabled
  MAINTAINERS: fix Rajendra Nayak's address
  mm, cma: prevent nr_isolated_* counters from going negative
  mm: update min_free_kbytes from khugepaged after core initialization
  huge pagecache: mmap_sem is unlocked when truncation splits pmd
  rapidio/mport_cdev: fix uapi type definitions
  mm: memcontrol: let v2 cgroups follow changes in system swappiness
  mm: thp: correct split_huge_pages file permission
2016-05-05 20:48:35 -07:00
Nikolay Aleksandrov
31ca0458a6 net: bridge: fix old ioctl unlocked net device walk
get_bridge_ifindices() is used from the old "deviceless" bridge ioctl
calls which aren't called with rtnl held. The comment above says that it is
called with rtnl but that is not really the case.
Here's a sample output from a test ASSERT_RTNL() which I put in
get_bridge_ifindices and executed "brctl show":
[  957.422726] RTNL: assertion failed at net/bridge//br_ioctl.c (30)
[  957.422925] CPU: 0 PID: 1862 Comm: brctl Tainted: G        W  O
4.6.0-rc4+ #157
[  957.423009] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS 1.8.1-20150318_183358- 04/01/2014
[  957.423009]  0000000000000000 ffff880058adfdf0 ffffffff8138dec5
0000000000000400
[  957.423009]  ffffffff81ce8380 ffff880058adfe58 ffffffffa05ead32
0000000000000001
[  957.423009]  00007ffec1a444b0 0000000000000400 ffff880053c19130
0000000000008940
[  957.423009] Call Trace:
[  957.423009]  [<ffffffff8138dec5>] dump_stack+0x85/0xc0
[  957.423009]  [<ffffffffa05ead32>]
br_ioctl_deviceless_stub+0x212/0x2e0 [bridge]
[  957.423009]  [<ffffffff81515beb>] sock_ioctl+0x22b/0x290
[  957.423009]  [<ffffffff8126ba75>] do_vfs_ioctl+0x95/0x700
[  957.423009]  [<ffffffff8126c159>] SyS_ioctl+0x79/0x90
[  957.423009]  [<ffffffff8163a4c0>] entry_SYSCALL_64_fastpath+0x23/0xc1

Since it only reads bridge ifindices, we can use rcu to safely walk the net
device list. Also remove the wrong rtnl comment above.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-05 23:32:30 -04:00
Ian Campbell
dedc58e067 VSOCK: do not disconnect socket when peer has shutdown SEND only
The peer may be expecting a reply having sent a request and then done a
shutdown(SHUT_WR), so tearing down the whole socket at this point seems
wrong and breaks for me with a client which does a SHUT_WR.

Looking at other socket family's stream_recvmsg callbacks doing a shutdown
here does not seem to be the norm and removing it does not seem to have
had any adverse effects that I can see.

I'm using Stefan's RFC virtio transport patches, I'm unsure of the impact
on the vmci transport.

Signed-off-by: Ian Campbell <ian.campbell@docker.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Cc: Andy King <acking@vmware.com>
Cc: Dmitry Torokhov <dtor@vmware.com>
Cc: Jorgen Hansen <jhansen@vmware.com>
Cc: Adit Ranadive <aditr@vmware.com>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-05 23:31:29 -04:00
Daniel Jurgens
82d69203df net/mlx4_en: Fix endianness bug in IPV6 csum calculation
Use htons instead of unconditionally byte swapping nexthdr.  On a little
endian systems shifting the byte is correct behavior, but it results in
incorrect csums on big endian architectures.

Fixes: f8c6455bb0 ('net/mlx4_en: Extend checksum offloading by CHECKSUM COMPLETE')
Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Reviewed-by: Carol Soto <clsoto@us.ibm.com>
Tested-by: Carol Soto <clsoto@us.ibm.com>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-05 23:26:14 -04:00
Linus Torvalds
43a3e837e2 mailmap: add John Paul Adrian Glaubitz
Apparently patchwork ended up truncating the full name.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05 20:07:14 -07:00
Linus Torvalds
7270a3f761 Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm fixes from Dan Williams:

 - a fix for the persistent memory 'struct page' driver.  The
   implementation overlooked the fact that pages are allocated in 2MB
   units leading to -ENOMEM when establishing some configurations.

   It's tagged for -stable as the problem was introduced with the
   initial implementation in 4.5.

 - The new "error status translation" routine, introduced with the 4.6
   updates to the nfit driver, missed a necessary path in
   acpi_nfit_ctl().

   The end result is that we are falsely assuming commands complete
   successfully when the embedded status says otherwise.

* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  nfit: fix translation of command status results
  libnvdimm, pfn: fix memmap reservation sizing
2016-05-05 18:10:01 -07:00
Arnd Bergmann
7322dd755e byteswap: try to avoid __builtin_constant_p gcc bug
This is another attempt to avoid a regression in wwn_to_u64() after that
started using get_unaligned_be64(), which in turn ran into a bug on
gcc-4.9 through 6.1.

The regression got introduced due to the combination of two separate
workarounds (commits e3bde9568d: "include/linux/unaligned: force
inlining of byteswap operations" and ef3fb2422f: "scsi: fc: use
get/put_unaligned64 for wwn access") that each try to sidestep distinct
problems with gcc behavior (code growth and increased stack usage).

Unfortunately after both have been applied, a more serious gcc bug has
been uncovered, leading to incorrect object code that discards part of a
function and causes undefined behavior.

As part of this problem is how __builtin_constant_p gets evaluated on an
argument passed by reference into an inline function, this avoids the
use of __builtin_constant_p() for all architectures that set
CONFIG_ARCH_USE_BUILTIN_BSWAP.  Most architectures do not set
ARCH_SUPPORTS_OPTIMIZED_INLINING, which means they probably do not
suffer from the problem in the qla2xxx driver, but they might still run
into it elsewhere.

Both of the original workarounds were only merged in the 4.6 kernel, and
the bug that is fixed by this patch should only appear if both are
there, so we probably don't need to backport the fix.  On the other
hand, it works by simplifying the code path and should not have any
negative effects.

[arnd@arndb.de: fix older gcc warnings]
  (http://lkml.kernel.org/r/12243652.bxSxEgjgfk@wuerfel)
Link: https://lkml.org/lkml/headers/2016/4/12/1103
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66122
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70232
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70646
Fixes: e3bde9568d ("include/linux/unaligned: force inlining of byteswap operations")
Fixes: ef3fb2422f ("scsi: fc: use get/put_unaligned64 for wwn access")
Link: http://lkml.kernel.org/r/1780465.XdtPJpi8Tt@wuerfel
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Tested-by: Josh Poimboeuf <jpoimboe@redhat.com> # on gcc-5.3
Tested-by: Quinn Tran <quinn.tran@qlogic.com>
Cc: Martin Jambor <mjambor@suse.cz>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: James Bottomley <James.Bottomley@hansenpartnership.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Himanshu Madhani <himanshu.madhani@qlogic.com>
Cc: Jan Hubicka <hubicka@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05 17:38:53 -07:00
Joonsoo Kim
7c31190bcf lib/stackdepot: avoid to return 0 handle
Recently, we allow to save the stacktrace whose hashed value is 0.  It
causes the problem that stackdepot could return 0 even if in success.
User of stackdepot cannot distinguish whether it is success or not so we
need to solve this problem.  In this patch, 1 bit are added to handle
and make valid handle none 0 by setting this bit.  After that, valid
handle will not be 0 and 0 handle will represent failure correctly.

Fixes: 33334e2576 ("lib/stackdepot.c: allow the stack trace hash to be zero")
Link: http://lkml.kernel.org/r/1462252403-1106-1-git-send-email-iamjoonsoo.kim@lge.com
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05 17:38:53 -07:00
Vlastimil Babka
172400c69c mm: fix kcompactd hang during memory offlining
Assume memory47 is the last online block left in node1.  This will hang:

  # echo offline > /sys/devices/system/node/node1/memory47/state

After a couple of minutes, the following pops up in dmesg:

  INFO: task bash:957 blocked for more than 120 seconds.
         Not tainted 4.6.0-rc6+ #6
  "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  bash            D ffff8800b7adbaf8     0   957    951 0x00000000
  Call Trace:
    schedule+0x35/0x80
    schedule_timeout+0x1ac/0x270
    wait_for_completion+0xe1/0x120
    kthread_stop+0x4f/0x110
    kcompactd_stop+0x26/0x40
    __offline_pages.constprop.28+0x7e6/0x840
    offline_pages+0x11/0x20
    memory_block_action+0x73/0x1d0
    memory_subsys_offline+0x47/0x60
    device_offline+0x86/0xb0
    store_mem_state+0xda/0xf0
    dev_attr_store+0x18/0x30
    sysfs_kf_write+0x37/0x40
    kernfs_fop_write+0x11d/0x170
    __vfs_write+0x37/0x120
    vfs_write+0xa9/0x1a0
    SyS_write+0x55/0xc0
    entry_SYSCALL_64_fastpath+0x1a/0xa4

kcompactd is waiting for kcompactd_max_order > 0 when it's woken up to
actually exit.  Check kthread_should_stop() to break out of the wait.

Fixes: 698b1b306 ("mm, compaction: introduce kcompactd").
Reported-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Tested-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05 17:38:53 -07:00
Philipp Zabel
acbef7b766 modpost: fix module autoloading for OF devices with generic compatible property
Since the wildcard at the end of OF module aliases is gone, autoloading
of modules that don't match a device's last (most generic) compatible
value fails.

For example the CODA960 VPU on i.MX6Q has the SoC specific compatible
"fsl,imx6q-vpu" and the generic compatible "cnm,coda960".  Since the
driver currently only works with knowledge about the SoC specific
integration, it doesn't list "cnm,cod960" in the module device table.

This results in the device compatible
"of:NvpuT<NULL>Cfsl,imx6q-vpuCcnm,coda960" not matching the module alias
"of:N*T*Cfsl,imx6q-vpu" anymore, whereas before commit 2f632369ab
("modpost: don't add a trailing wildcard for OF module aliases") it
matched the module alias "of:N*T*Cfsl,imx6q-vpu*".

This patch adds two module aliases for each compatible, one without the
wildcard and one with "C*" appended.

  $ modinfo coda | grep imx6q
  alias:          of:N*T*Cfsl,imx6q-vpuC*
  alias:          of:N*T*Cfsl,imx6q-vpu

Fixes: 2f632369ab ("modpost: don't add a trailing wildcard for OF module aliases")
Link: http://lkml.kernel.org/r/1462203339-15340-1-git-send-email-p.zabel@pengutronix.de
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Javier Martinez Canillas <javier@osg.samsung.com>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org>	[4.5+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05 17:38:53 -07:00
Mathias Krause
8148a73c99 proc: prevent accessing /proc/<PID>/environ until it's ready
If /proc/<PID>/environ gets read before the envp[] array is fully set up
in create_{aout,elf,elf_fdpic,flat}_tables(), we might end up trying to
read more bytes than are actually written, as env_start will already be
set but env_end will still be zero, making the range calculation
underflow, allowing to read beyond the end of what has been written.

Fix this as it is done for /proc/<PID>/cmdline by testing env_end for
zero.  It is, apparently, intentionally set last in create_*_tables().

This bug was found by the PaX size_overflow plugin that detected the
arithmetic underflow of 'this_len = env_end - (env_start + src)' when
env_end is still zero.

The expected consequence is that userland trying to access
/proc/<PID>/environ of a not yet fully set up process may get
inconsistent data as we're in the middle of copying in the environment
variables.

Fixes: https://forums.grsecurity.net/viewtopic.php?f=3&t=4363
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=116461
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Emese Revfy <re.emese@gmail.com>
Cc: Pax Team <pageexec@freemail.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Mateusz Guzik <mguzik@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05 17:38:53 -07:00
Dan Streetman
32a4e16903 mm/zswap: provide unique zpool name
Instead of using "zswap" as the name for all zpools created, add an
atomic counter and use "zswap%x" with the counter number for each zpool
created, to provide a unique name for each new zpool.

As zsmalloc, one of the zpool implementations, requires/expects a unique
name for each pool created, zswap should provide a unique name.  The
zsmalloc pool creation does not fail if a new pool with a conflicting
name is created, unless CONFIG_ZSMALLOC_STAT is enabled; in that case,
zsmalloc pool creation fails with -ENOMEM.  Then zswap will be unable to
change its compressor parameter if its zpool is zsmalloc; it also will
be unable to change its zpool parameter back to zsmalloc, if it has any
existing old zpool using zsmalloc with page(s) in it.  Attempts to
change the parameters will result in failure to create the zpool.  This
changes zswap to provide a unique name for each zpool creation.

Fixes: f1c54846ee ("zswap: dynamic pool creation")
Signed-off-by: Dan Streetman <ddstreet@ieee.org>
Reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Dan Streetman <dan.streetman@canonical.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05 17:38:53 -07:00
Andrea Arcangeli
127393fbe5 mm: thp: kvm: fix memory corruption in KVM with THP enabled
After the THP refcounting change, obtaining a compound pages from
get_user_pages() no longer allows us to assume the entire compound page
is immediately mappable from a secondary MMU.

A secondary MMU doesn't want to call get_user_pages() more than once for
each compound page, in order to know if it can map the whole compound
page.  So a secondary MMU needs to know from a single get_user_pages()
invocation when it can map immediately the entire compound page to avoid
a flood of unnecessary secondary MMU faults and spurious
atomic_inc()/atomic_dec() (pages don't have to be pinned by MMU notifier
users).

Ideally instead of the page->_mapcount < 1 check, get_user_pages()
should return the granularity of the "page" mapping in the "mm" passed
to get_user_pages().  However it's non trivial change to pass the "pmd"
status belonging to the "mm" walked by get_user_pages up the stack (up
to the caller of get_user_pages).  So the fix just checks if there is
not a single pte mapping on the page returned by get_user_pages, and in
turn if the caller can assume that the whole compound page is mapped in
the current "mm" (in a pmd_trans_huge()).  In such case the entire
compound page is safe to map into the secondary MMU without additional
get_user_pages() calls on the surrounding tail/head pages.  In addition
of being faster, not having to run other get_user_pages() calls also
reduces the memory footprint of the secondary MMU fault in case the pmd
split happened as result of memory pressure.

Without this fix after a MADV_DONTNEED (like invoked by QEMU during
postcopy live migration or balloning) or after generic swapping (with a
failure in split_huge_page() that would only result in pmd splitting and
not a physical page split), KVM would map the whole compound page into
the shadow pagetables, despite regular faults or userfaults (like
UFFDIO_COPY) may map regular pages into the primary MMU as result of the
pte faults, leading to the guest mode and userland mode going out of
sync and not working on the same memory at all times.

Any other secondary MMU notifier manager (KVM is just one of the many
MMU notifier users) will need the same information if it doesn't want to
run a flood of get_user_pages_fast and it can support multiple
granularity in the secondary MMU mappings, so I think it is justified to
be exposed not just to KVM.

The other option would be to move transparent_hugepage_adjust to
mm/huge_memory.c but that currently has all kind of KVM data structures
in it, so it's definitely not a cut-and-paste work, so I couldn't do a
fix as cleaner as this one for 4.6.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: "Li, Liang Z" <liang.z.li@intel.com>
Cc: Amit Shah <amit.shah@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05 17:38:53 -07:00
Eric Engestrom
ff2de822c9 MAINTAINERS: fix Rajendra Nayak's address
Signed-off-by: Eric Engestrom <eric.engestrom@imgtec.com>
Cc: Rajendra Nayak <rnayak@codeaurora.org>
Cc: Afzal Mohammed <afzal.mohd.ma@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05 17:38:53 -07:00
Hugh Dickins
14af4a5e9b mm, cma: prevent nr_isolated_* counters from going negative
/proc/sys/vm/stat_refresh warns nr_isolated_anon and nr_isolated_file go
increasingly negative under compaction: which would add delay when
should be none, or no delay when should delay.  The bug in compaction
was due to a recent mmotm patch, but much older instance of the bug was
also noticed in isolate_migratepages_range() which is used for CMA and
gigantic hugepage allocations.

The bug is caused by putback_movable_pages() in an error path
decrementing the isolated counters without them being previously
incremented by acct_isolated().  Fix isolate_migratepages_range() by
removing the error-path putback, thus reaching acct_isolated() with
migratepages still isolated, and leaving putback to caller like most
other places do.

Fixes: edc2ca6124 ("mm, compaction: move pageblock checks up from isolate_migratepages_range()")
[vbabka@suse.cz: expanded the changelog]
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05 17:38:53 -07:00
Jason Baron
bc22af74f2 mm: update min_free_kbytes from khugepaged after core initialization
Khugepaged attempts to raise min_free_kbytes if its set too low.
However, on boot khugepaged sets min_free_kbytes first from
subsys_initcall(), and then the mm 'core' over-rides min_free_kbytes
after from init_per_zone_wmark_min(), via a module_init() call.

Khugepaged used to use a late_initcall() to set min_free_kbytes (such
that it occurred after the core initialization), however this was
removed when the initialization of min_free_kbytes was integrated into
the starting of the khugepaged thread.

The fix here is simply to invoke the core initialization using a
core_initcall() instead of module_init(), such that the previous
initialization ordering is restored.  I didn't restore the
late_initcall() since start_stop_khugepaged() already sets
min_free_kbytes via set_recommended_min_free_kbytes().

This was noticed when we had a number of page allocation failures when
moving a workload to a kernel with this new initialization ordering.  On
an 8GB system this restores min_free_kbytes back to 67584 from 11365
when CONFIG_TRANSPARENT_HUGEPAGE=y is set and either
CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS=y or
CONFIG_TRANSPARENT_HUGEPAGE_MADVISE=y.

Fixes: 79553da293 ("thp: cleanup khugepaged startup")
Signed-off-by: Jason Baron <jbaron@akamai.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05 17:38:53 -07:00
Hugh Dickins
684283988f huge pagecache: mmap_sem is unlocked when truncation splits pmd
zap_pmd_range()'s CONFIG_DEBUG_VM !rwsem_is_locked(&mmap_sem) BUG() will
be invalid with huge pagecache, in whatever way it is implemented:
truncation of a hugely-mapped file to an unhugely-aligned size would
easily hit it.

(Although anon THP could in principle apply khugepaged to private file
mappings, which are not excluded by the MADV_HUGEPAGE restrictions, in
practice there's a vm_ops check which excludes them, so it never hits
this BUG() - there's no interface to "truncate" an anonymous mapping.)

We could complicate the test, to check i_mmap_rwsem also when there's a
vm_file; but my inclination was to make zap_pmd_range() more readable by
simply deleting this check.  A search has shown no report of the issue
in the years since commit e0897d75f0 ("mm, thp: print useful
information when mmap_sem is unlocked in zap_pmd_range") expanded it
from VM_BUG_ON() - though I cannot point to what commit I would say then
fixed the issue.

But there are a couple of other patches now floating around, neither yet
in the tree: let's agree to retain the check as a VM_BUG_ON_VMA(), as
Matthew Wilcox has done; but subject to a vma_is_anonymous() check, as
Kirill Shutemov has done.  And let's get this in, without waiting for
any particular huge pagecache implementation to reach the tree.

Matthew said "We can reproduce this BUG() in the current Linus tree with
DAX PMDs".

Signed-off-by: Hugh Dickins <hughd@google.com>
Tested-by: Matthew Wilcox <willy@linux.intel.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Yang Shi <yang.shi@linaro.org>
Cc: Ning Qu <quning@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05 17:38:53 -07:00
Alexandre Bounine
4e1016dac1 rapidio/mport_cdev: fix uapi type definitions
Fix problems in uapi definitions reported by Gabriel Laskar: (see
https://lkml.org/lkml/2016/4/5/205 for details)

 - move public header file rio_mport_cdev.h to include/uapi/linux directory
 - change types in data structures passed as IOCTL parameters
 - improve parameter checking in some IOCTL service routines

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Reported-by: Gabriel Laskar <gabriel@lse.epita.fr>
Tested-by: Barry Wood <barry.wood@idt.com>
Cc: Gabriel Laskar <gabriel@lse.epita.fr>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: Andre van Herk <andre.van.herk@prodrive-technologies.com>
Cc: Barry Wood <barry.wood@idt.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05 17:38:53 -07:00
Johannes Weiner
4550c4e157 mm: memcontrol: let v2 cgroups follow changes in system swappiness
Cgroup2 currently doesn't have a per-cgroup swappiness setting.  We
might want to add one later - that's a different discussion - but until
we do, the cgroups should always follow the system setting.  Otherwise
it will be unchangeably set to whatever the ancestor inherited from the
system setting at the time of cgroup creation.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: <stable@vger.kernel.org>	[4.5]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05 17:38:53 -07:00
Yang Shi
145bdaa150 mm: thp: correct split_huge_pages file permission
split_huge_pages doesn't support get method at all, so the read
permission sounds confusing, change the permission to write only.

And, add "\n" to the output of set method to make it more readable.

Signed-off-by: Yang Shi <yang.shi@linaro.org>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05 17:38:53 -07:00
Wang Nan
b6b85dad30 perf evlist: Rename variable in perf_mmap__read()
In perf_mmap__read(), give better names to pointers. Original name 'old'
and 'head' directly related to pointers in ring buffer control page. For
backward ring buffer, the meaning of 'head' point is not 'the first byte
of free space', but 'the first byte of the last record'. To reduce
confusion, rename 'old' to 'start', 'head' to 'end'.  'start' -> 'end'
is the direction the records should be read from.

Change parameter order.

Change 'overwrite' to 'check_messup'. When reading from 'head', no need
to check messup for for backward ring buffer.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1461723563-67451-3-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:04:04 -03:00
Wang Nan
0f4ccd1181 perf evlist: Extract perf_mmap__read()
Extract event reader from perf_evlist__mmap_read() to perf__mmap_read().
Future commit will feed it with manually computed 'head' and 'old'
pointers.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1461723563-67451-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:04:03 -03:00
Naveen N. Rao
0b3c2264ae perf symbols: Fix kallsyms perf test on ppc64le
ppc64le functions have a Global Entry Point (GEP) and a Local Entry
Point (LEP). While placing a probe, we always prefer the LEP since it
catches function calls through both the GEP and the LEP. In order to do
this, we fixup the function entry points during elf symbol table lookup
to point to the LEPs. This works, but breaks 'perf test kallsyms' since
the symbols loaded from the symbol table (pointing to the LEP) do not
match the symbols in kallsyms.

To fix this, we do not adjust all the symbols during symbol table load.
Instead, we note down st_other in a newly introduced arch-specific
member of perf symbol structure, and later use this to adjust the probe
trace point.

Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Cc: Mark Wielaard <mjw@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/6be7c2b17e370100c2f79dd444509df7929bdd3e.1460451721.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:04:03 -03:00
Naveen N. Rao
239aeba764 perf powerpc: Fix kprobe and kretprobe handling with kallsyms on ppc64le
So far, we used to treat probe point offsets as being offset from the
LEP. However, userspace applications (objdump/readelf) always show
disassembly and offsets from the function GEP. This is confusing to the
user as we will end up probing at an address different from what the
user expects when looking at the function disassembly with
readelf/objdump. Fix this by changing how we modify probe address with
perf.

If only the function name is provided, we assume the user needs the LEP.
Otherwise, if an offset is specified, we assume that the user knows the
exact address to probe based on function disassembly, and so we just
place the probe from the GEP offset.

Finally, kretprobe was also broken with kallsyms as we were trying to
specify an offset. This patch also fixes that issue.

Reported-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Cc: Mark Wielaard <mjw@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/75df860aad8216bf4b9bcd10c6351ecc0e3dee54.1460451721.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:04:02 -03:00
Jiri Olsa
7cecb7fe83 perf hists: Move sort__has_comm into struct perf_hpp_list
Now we have sort dimensions private for struct hists,
we need to make dimension booleans hists specific as
well.

Moving sort__has_comm into struct perf_hpp_list.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1462276488-26683-8-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:04:02 -03:00
Jiri Olsa
fa82911a1b perf hists: Move sort__has_thread into struct perf_hpp_list
Now we have sort dimensions private for struct hists, we need to make
dimension booleans hists specific as well.

Moving sort__has_thread into struct perf_hpp_list.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1462276488-26683-7-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:04:01 -03:00
Jiri Olsa
35a634f76c perf hists: Move sort__has_socket into struct perf_hpp_list
Now we have sort dimensions private for struct hists, we need to make
dimension booleans hists specific as well.

Moving sort__has_socket into struct perf_hpp_list.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1462276488-26683-6-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:04:01 -03:00
Jiri Olsa
69849fc5d2 perf hists: Move sort__has_dso into struct perf_hpp_list
Now we have sort dimensions private for struct hists, we need to make
dimension booleans hists specific as well.

Moving sort__has_dso into struct perf_hpp_list.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1462276488-26683-5-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:04:00 -03:00
Jiri Olsa
2e0453af4e perf hists: Move sort__has_sym into struct perf_hpp_list
Now we have sort dimensions private for struct hists, we need to make
dimension booleans hists specific as well.

Moving sort__has_sym into struct perf_hpp_list.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1462276488-26683-4-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:03:59 -03:00
Jiri Olsa
de7e6a7c8b perf hists: Move sort__has_parent into struct perf_hpp_list
Now we have sort dimensions private for struct hists, we need to make
dimension booleans hists specific as well.

Moving sort__has_parent into struct perf_hpp_list.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1462276488-26683-3-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:03:59 -03:00
Jiri Olsa
52225036fa perf hists: Move sort__need_collapse into struct perf_hpp_list
Now we have sort dimensions private for struct hists, we need to make
dimension booleans hists specific as well.

Moving sort__need_collapse into struct perf_hpp_list.

Adding hists__has macro to easily access this info perf struct hists
object.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1462276488-26683-2-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:03:58 -03:00
Naveen N. Rao
4679bccaa3 perf tools powerpc: Add support for generating bpf prologue
Generalize existing macros to serve the purpose.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Ian Munsie <imunsie@au1.ibm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/1462461799-17518-1-git-send-email-naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:03:58 -03:00
Arnaldo Carvalho de Melo
03548ebf6d perf trace: Do not show the runtime_ms for a thread when not collecting it
That field is only updated when we use the "sched:sched_stat_runtime"
tracepoint, and that is only done so far when we use the '--stat' command line
option, without it we get just zeros, confusing the users:

Without this patch:

  # trace -a -s sleep 1
  <SNIP>
   qemu-system-x86 (9931), 468 events, 9.6%, 0.000 msec

     syscall     calls    total       min       avg       max      stddev
                          (msec)    (msec)    (msec)    (msec)        (%)
     ---------- ------ --------- --------- --------- ---------     ------
     ppoll          98   982.374     0.000    10.024    29.983     12.65%
     write          34     0.401     0.005     0.012     0.027      5.49%
     ioctl         102     0.347     0.002     0.003     0.007      3.08%

   firefox (10871), 1856 events, 38.2%, 0.000 msec

                          (msec)    (msec)    (msec)    (msec)        (%)
     ---------- ------ --------- --------- --------- ---------     ------
     poll          395   934.873     0.000     2.367    17.120     11.51%
     recvmsg       395     0.988     0.001     0.003     0.021      4.20%
     read          106     0.460     0.002     0.004     0.007      3.17%
     futex          24     0.108     0.001     0.004     0.010     10.05%
     mmap            2     0.041     0.016     0.021     0.026     23.92%
     write           6     0.027     0.004     0.004     0.005      2.52%

After this patch that ', 0.000 msecs' gets suppressed when --stat is not
in use.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-p7emqrsw7900tdkg43v9l1e1@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:03:57 -03:00
Arnaldo Carvalho de Melo
b535d523dc perf trace: Sort syscalls stats by msecs in --summary
# trace -a -s sleep 1
  <SNIP>
   Xorg (1965), 788 events, 19.0%, 0.000 msec

     syscall            calls    total       min       avg       max      stddev
                                 (msec)    (msec)    (msec)    (msec)        (%)
     --------------- -------- --------- --------- --------- ---------     ------
     select                89   731.038     0.000     8.214   175.218     36.71%
     ioctl                 22     0.661     0.010     0.030     0.072     10.43%
     writev                42     0.253     0.002     0.006     0.011      5.94%
     recvmsg               60     0.185     0.001     0.003     0.009      5.90%
     setitimer             60     0.127     0.001     0.002     0.006      6.14%
     read                  52     0.102     0.001     0.002     0.005      8.55%
     rt_sigprocmask        45     0.092     0.001     0.002     0.023     23.65%
     poll                  12     0.021     0.001     0.002     0.003      7.21%
     epoll_wait            12     0.019     0.001     0.002     0.002      2.71%

   firefox (10871), 1080 events, 26.1%, 0.000 msec

     syscall            calls    total       min       avg       max      stddev
                                 (msec)    (msec)    (msec)    (msec)        (%)
     --------------- -------- --------- --------- --------- ---------     ------
     poll                 240   979.562     0.000     4.082    17.132     11.33%
     recvmsg              240     0.532     0.001     0.002     0.007      3.69%
     read                  60     0.303     0.003     0.005     0.029      8.50%

Suggested-by: Milian Wolff <milian.wolff@kdab.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-52kdkuyxihq0kvc0n2aalhay@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:03:56 -03:00
Arnaldo Carvalho de Melo
96c1445122 perf trace: Sort summary output by number of events
# trace -a -s sleep 1 |& grep events | tail
   gmain (1733), 34 events, 1.0%, 0.000 msec
   hexchat (9765), 46 events, 1.4%, 0.000 msec
   ssh (11109), 80 events, 2.4%, 0.000 msec
   sleep (32631), 81 events, 2.4%, 0.000 msec
   qemu-system-x86 (10021), 272 events, 8.2%, 0.000 msec
   Xorg (1965), 322 events, 9.7%, 0.000 msec
   SoftwareVsyncTh (10922), 366 events, 11.1%, 0.000 msec
   gnome-shell (2231), 446 events, 13.5%, 0.000 msec
   qemu-system-x86 (9931), 468 events, 14.1%, 0.000 msec
   firefox (10871), 1098 events, 33.2%, 0.000 msec
  [root@jouet ~]#

Suggested-by: Milian Wolff <milian.wolff@kdab.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-ye4cnprhfeiq32ar4lt60dqs@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:03:56 -03:00
Arnaldo Carvalho de Melo
f58c253564 perf tools: Add template for generating rbtree resort class
Sometimes we want to sort an existing rbtree by a different key,
introduce a template for that, that needs only to be provided the
rbtree root and the number of entries in it.

To do that a new rbtree will be created with extra space for each entry,
where possibly pre-calculated keys will be stored to be used in the
resort process and also later, when using the newly sorted rbtree.

Please check the following two changesets to see it in use for resorting
stats for threads and its syscalls in 'perf trace --summary'.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-9l6e1q34lmf3wwdeewstyakg@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:03:55 -03:00
Arnaldo Carvalho de Melo
d2c1103440 perf machine: Introduce number of threads member
To be used, for instance, for pre-allocating an rb_tree array for
sorting by other keys besides the current pid one.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-ja0ifkwue7ttjhbwijn6g6eu@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-05-05 21:03:55 -03:00
Linus Torvalds
85f397a97a asm-generic syscall fix for 4.6-rc
My last pull request for asm-generic had just one patch that added two
 new system calls to asm/unistd.h, but unfortunately it turned out
 to be wrong, pointing arch/tile compat mode at the native handlers
 rather than the compat ones.
 
 This was spotted by Yury Norov, who is working on ILP32 mode
 for arch/arm64, which would have the same problem when merged.
 This fixes the table to use the correct compat syscalls, like
 the other 64-bit architectures do.
 
 I'll try to find the time to come up with a solution that
 prevents this problem from happening again, by allowing all
 future system calls to just get added in a single file
 for use by all architectures.
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Merge tag 'asm-generic-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic

Pull asm-generic syscall fix from Arnd Bergmann:
 "My last pull request for asm-generic had just one patch that added two
  new system calls to asm/unistd.h, but unfortunately it turned out to
  be wrong, pointing arch/tile compat mode at the native handlers rather
  than the compat ones.

  This was spotted by Yury Norov, who is working on ILP32 mode for
  arch/arm64, which would have the same problem when merged.  This fixes
  the table to use the correct compat syscalls, like the other 64-bit
  architectures do.

  I'll try to find the time to come up with a solution that prevents
  this problem from happening again, by allowing all future system calls
  to just get added in a single file for use by all architectures"

* tag 'asm-generic-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
  asm-generic: use compat version for preadv2 and pwritev2
2016-05-05 15:40:38 -07:00
Greg Kroah-Hartman
2b86c4a843 Fourth set of IIO fixes for the 4.6 cycle.
This last minute set is concerned with a regression in the mpu6050 driver.
 The regression causes a null pointer dereference on any ACPI device
 that has one of these present such as the ASUS T100TA Baytrail/T.
 
 The issue was known but thought (i.e. missunderstood by me)
 to only be a possible with no reports, so was routed via the normal merge
 window.  Turns out this was wrong (thanks to Alan for reporting the crash).
 
 The pull is just for the null dereference fix and a followup fix
 that also stops the reported name of the device being NULL.
 
 * mpu6050
   - Fix a 'possible' NULL dereference introduced as part of splitting the
   driver to allow both i2c and spi to be supported.  The issue affects ACPI
   systems with this device.
   - Fix a follow up issue where the name and chip id both get set to null if
   the device driver instance is instantiated from ACPI tables.
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Merge tag 'iio-fixes-for-4.6d' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-linus

Jonathan writes:

Fourth set of IIO fixes for the 4.6 cycle.

This last minute set is concerned with a regression in the mpu6050 driver.
The regression causes a null pointer dereference on any ACPI device
that has one of these present such as the ASUS T100TA Baytrail/T.

The issue was known but thought (i.e. missunderstood by me)
to only be a possible with no reports, so was routed via the normal merge
window.  Turns out this was wrong (thanks to Alan for reporting the crash).

The pull is just for the null dereference fix and a followup fix
that also stops the reported name of the device being NULL.

* mpu6050
  - Fix a 'possible' NULL dereference introduced as part of splitting the
  driver to allow both i2c and spi to be supported.  The issue affects ACPI
  systems with this device.
  - Fix a follow up issue where the name and chip id both get set to null if
  the device driver instance is instantiated from ACPI tables.
2016-05-05 15:38:07 -07:00
Linus Torvalds
c4781a8df9 Here are a couple last-minute fixes for ARM SoCs. Most of them
are for the OMAP platforms, quoting Tony Lindgren:
 
     Fixes for omaps for v4.6-rc cycle. All dts fixes, mostly
     affecting voltages and pinctrl for various device drivers:
 
     - Regulator minimum voltage fixes for omap5
     - ISP syscon register offset fix for omap3
     - Fix regulator initial modes for n900
     - Fix omap5 pinctrl wkup instance size
 
 The rest are all for different platforms:
 
 - Allwinner:
    Remove incorrect constraints from a dcdc1 regulator
 
 - Alltera SoCFPGA:
   Fix compilation in thumb2 mode
 
 - Samsung exynos:
   Fix a potential oops in the pm-domain error handling
 
 - Davinci:
   Avoid a link error if NVMEM is disabled
 
 - Renesas:
   Do not mark an external uart clock as disabled, to allow
   probing the uarts
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Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC fixes from Arnd Bergmann:
 "Here are a couple last-minute fixes for ARM SoCs.  Most of them are
  for the OMAP platforms, the rest are all for different platforms.

  OMAP:
     All dts fixes, mostly affecting voltages and pinctrl for various
     device drivers:

      - Regulator minimum voltage fixes for omap5
      - ISP syscon register offset fix for omap3
      - Fix regulator initial modes for n900
      - Fix omap5 pinctrl wkup instance size

  Allwinner:
     Remove incorrect constraints from a dcdc1 regulator

  Alltera SoCFPGA:
     Fix compilation in thumb2 mode

  Samsung exynos:
     Fix a potential oops in the pm-domain error handling

  Davinci:
     Avoid a link error if NVMEM is disabled

  Renesas:
     Do not mark an external uart clock as disabled, to allow probing
     the uarts"

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: davinci: only use NVMEM when available
  ARM: SoCFPGA: Fix secondary CPU startup in thumb2 kernel
  ARM: dts: omap5: fix range of permitted wakeup pinmux registers
  ARM: dts: omap3-n900: Specify peripherals LDO regulators initial mode
  ARM: dts: omap3: Fix ISP syscon register offset
  ARM: dts: omap5-cm-t54: fix ldo1_reg and ldo4_reg ranges
  ARM: dts: omap5-board-common: fix ldo1_reg and ldo4_reg ranges
  arm64: dts: r8a7795: Don't disable referenced optional scif clock
  ARM: EXYNOS: Properly skip unitialized parent clock in power domain on
  ARM: dts: sun8i-q8-common: Do not set constraints on dc1sw regulator
2016-05-05 15:31:35 -07:00
Russell King
54176cc680 maintainers: update rmk's email address(es)
Update my email and web addresses in the kernel maintainers file.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-05 15:26:31 -07:00
Howard Cochran
74d3694433 writeback: Fix performance regression in wb_over_bg_thresh()
Commit 947e9762a8 ("writeback: update wb_over_bg_thresh() to use
wb_domain aware operations") unintentionally changed this function's
meaning from "are there more dirty pages than the background writeback
threshold" to "are there more dirty pages than the writeback threshold".
The background writeback threshold is typically half of the writeback
threshold, so this had the effect of raising the number of dirty pages
required to cause a writeback worker to perform background writeout.

This can cause a very severe performance regression when a BDI uses
BDI_CAP_STRICTLIMIT because balance_dirty_pages() and the writeback worker
can now disagree on whether writeback should be initiated.

For example, in a system having 1GB of RAM, a single spinning disk, and a
"pass-through" FUSE filesystem mounted over the disk, application code
mmapped a 128MB file on the disk and was randomly dirtying pages in that
mapping.

Because FUSE uses strictlimit and has a default max_ratio of only 1%, in
balance_dirty_pages, thresh is ~200, bg_thresh is ~100, and the
dirty_freerun_ceiling is the average of those, ~150. So, it pauses the
dirtying processes when we have 151 dirty pages and wakes up a background
writeback worker. But the worker tests the wrong threshold (200 instead of
100), so it does not initiate writeback and just returns.

Thus, balance_dirty_pages keeps looping, sleeping and then waking up the
worker who will do nothing. It remains stuck in this state until the few
dirty pages that we have finally expire and we write them back for that
reason. Then the whole process repeats, resulting in near-zero throughput
through the FUSE BDI.

The fix is to call the parameterized variant of wb_calc_thresh, so that the
worker will do writeback if the bg_thresh is exceeded which was the
behavior before the referenced commit.

Fixes: 947e9762a8 ("writeback: update wb_over_bg_thresh() to use wb_domain aware operations")
Signed-off-by: Howard Cochran <hcochran@kernelspring.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: <stable@vger.kernel.org> # v4.2+
Tested-by Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-05-05 15:44:55 -06:00
Vladimir Murzin
ec953b70f3 ARM: 8573/1: domain: move {set,get}_domain under config guard
Recursive undefined instrcution falut is seen with R-class taking an
exception. The reson for that is __show_regs() tries to get domain
information, but domains is not available on !MMU cores, like R/M
class.

Fix it by puting {set,get}_domain functions under CONFIG_CPU_CP15_MMU
guard and providing stubs for the case where domains is not supported.

Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-05-05 19:03:02 +01:00
Jean-Philippe Brucker
5b526bd925 ARM: 8572/1: nommu: change memory reserve for the vectors
Commit 19accfd3 (ARM: move vector stubs) moved the vector stubs in an
additional page above the base vector one. This change wasn't taken into
account by the nommu memreserve.
This patch ensures that the kernel won't overwrite any vector stub on
nommu.

[changed the MPU side too]

Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-05-05 19:03:02 +01:00
Jean-Philippe Brucker
695665b0c5 ARM: 8571/1: nommu: fix PMSAv7 setup
Commit 1c2f87c (ARM: 8025/1: Get rid of meminfo) broke the support for
MPU on ARMv7-R. This patch adapts the code inside CONFIG_ARM_MPU to use
memblocks appropriately.

MPU initialisation only uses the first memory region, and removes all
subsequent ones. Because looping over all regions that need removal is
inefficient, and memblock_remove already handles memory ranges, we can
flatten the 'for_each_memblock' part.

Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-05-05 19:03:01 +01:00
Christoph Hellwig
9c674815d3 IB/iser: Fix max_sectors calculation
iSER currently has a couple places that set max_sectors in either the host
template or SCSI host, and all of them get it wrong.

This patch instead uses a single assignment that (hopefully) gets it right:
the max_sectors value must be derived from the number of segments in the
FR or FMR structure, but actually be one lower than the page size multiplied
by the number of sectors, as it has to handle the case of non-aligned I/O.

Without this I get trivial to reproduce hangs when running xfstests
(on XFS) over iSER to Linux targets.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Acked-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2016-05-05 12:41:24 -04:00