Commit Graph

364 Commits

Author SHA1 Message Date
Linus Torvalds
eafdca4d70 Staging/IIO patches for 4.18-rc1
Here is the big staging and IIO driver update for 4.18-rc1.
 
 It was delayed as I wanted to make sure the final driver deletions did
 not cause any major merge issues, and all now looks good.
 
 There are a lot of patches here, just over 1000.  The diffstat summary
 shows the major changes here:
 	1007 files changed, 16828 insertions(+), 227770 deletions(-)
 Because of this, we might be close to shrinking the overall kernel
 source code size for two releases in a row.
 
 There was loads of work in this release cycle, primarily:
 	- tons of ks7010 driver cleanups
 	- lots of mt7621 driver fixes and cleanups
 	- most driver cleanups
 	- wilc1000 fixes and cleanups
 	- lots and lots of IIO driver cleanups and new additions
 	- debugfs cleanups for all staging drivers
 	- lots of other staging driver cleanups and fixes, the shortlog
 	  has the full details.
 
 but the big user-visable things here are the removal of 3 chunks of
 code:
 	- ncpfs and ipx were removed on schedule, no one has cared about
 	  this code since it moved to staging last year, and if it needs
 	  to come back, it can be reverted.
 	- lustre file system is removed.  I've ranted at the lustre
 	  developers about once a year for the past 5 years, with no
 	  real forward progress at all to clean things up and get the
 	  code into the "real" part of the kernel.  Given that the
 	  lustre developers continue to work on an external tree and try
 	  to port those changes to the in-kernel tree every once in a
 	  while, this whole thing really really is not working out at
 	  all.  So I'm deleting it so that the developers can spend the
 	  time working in their out-of-tree location and get things
 	  cleaned up properly to get merged into the tree correctly at a
 	  later date.
 
 Because of these file removals, you will have merge issues on some of
 these files (2 in the ipx code, 1 in the ncpfs code, and 1 in the
 atomisp driver).  Just delete those files, it's a simple merge :)
 
 All of this has been in linux-next for a while with no reported
 problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging/IIO updates from Greg KH:
 "Here is the big staging and IIO driver update for 4.18-rc1.

  It was delayed as I wanted to make sure the final driver deletions did
  not cause any major merge issues, and all now looks good.

  There are a lot of patches here, just over 1000. The diffstat summary
  shows the major changes here:

	1007 files changed, 16828 insertions(+), 227770 deletions(-)

  Because of this, we might be close to shrinking the overall kernel
  source code size for two releases in a row.

  There was loads of work in this release cycle, primarily:

   - tons of ks7010 driver cleanups

   - lots of mt7621 driver fixes and cleanups

   - most driver cleanups

   - wilc1000 fixes and cleanups

   - lots and lots of IIO driver cleanups and new additions

   - debugfs cleanups for all staging drivers

   - lots of other staging driver cleanups and fixes, the shortlog has
     the full details.

  but the big user-visable things here are the removal of 3 chunks of
  code:

   - ncpfs and ipx were removed on schedule, no one has cared about this
     code since it moved to staging last year, and if it needs to come
     back, it can be reverted.

   - lustre file system is removed.

     I've ranted at the lustre developers about once a year for the past
     5 years, with no real forward progress at all to clean things up
     and get the code into the "real" part of the kernel.

     Given that the lustre developers continue to work on an external
     tree and try to port those changes to the in-kernel tree every once
     in a while, this whole thing really really is not working out at
     all. So I'm deleting it so that the developers can spend the time
     working in their out-of-tree location and get things cleaned up
     properly to get merged into the tree correctly at a later date.

  Because of these file removals, you will have merge issues on some of
  these files (2 in the ipx code, 1 in the ncpfs code, and 1 in the
  atomisp driver). Just delete those files, it's a simple merge :)

  All of this has been in linux-next for a while with no reported
  problems"

* tag 'staging-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (1011 commits)
  staging: ipx: delete it from the tree
  ncpfs: remove uapi .h files
  ncpfs: remove Documentation
  ncpfs: remove compat functionality
  staging: ncpfs: delete it
  staging: lustre: delete the filesystem from the tree.
  staging: vc04_services: no need to save the log debufs dentries
  staging: vc04_services: vchiq_debugfs_log_entry can be a void *
  staging: vc04_services: remove struct vchiq_debugfs_info
  staging: vc04_services: move client dbg directory into static variable
  staging: vc04_services: remove odd vchiq_debugfs_top() wrapper
  staging: vc04_services: no need to check debugfs return values
  staging: mt7621-gpio: reorder includes alphabetically
  staging: mt7621-gpio: change gc_map to don't use pointers
  staging: mt7621-gpio: use GPIOF_DIR_OUT and GPIOF_DIR_IN macros instead of custom values
  staging: mt7621-gpio: change 'to_mediatek_gpio' to make just a one line return
  staging: mt7621-gpio: dt-bindings: update documentation for #interrupt-cells property
  staging: mt7621-gpio: update #interrupt-cells for the gpio node
  staging: mt7621-gpio: dt-bindings: complete documentation for the gpio
  staging: mt7621-dts: add missing properties to gpio node
  ...
2018-06-09 10:32:39 -07:00
Stefan Agner
1c4bc43ddf mm/memblock: introduce PHYS_ADDR_MAX
So far code was using ULLONG_MAX and type casting to obtain a
phys_addr_t with all bits set.  The typecast is necessary to silence
compiler warnings on 32-bit platforms.

Use the simpler but still type safe approach "~(phys_addr_t)0" to create a
preprocessor define for all bits set.

Link: http://lkml.kernel.org/r/20180406213809.566-1-stefan@agner.ch
Signed-off-by: Stefan Agner <stefan@agner.ch>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-07 17:34:35 -07:00
Thomas Gleixner
c1a957d170 PM / suspend: Prevent might sleep splats
timekeeping suspend/resume calls read_persistent_clock() which takes
rtc_lock. That results in might sleep warnings because at that point
we run with interrupts disabled.

We cannot convert rtc_lock to a raw spinlock as that would trigger
other might sleep warnings.

As a workaround we disable the might sleep warnings by setting
system_state to SYSTEM_SUSPEND before calling sysdev_suspend() and
restoring it to SYSTEM_RUNNING afer sysdev_resume(). There is no lock
contention because hibernate / suspend to RAM is single-CPU at this
point.

In s2idle's case the system_state is set to SYSTEM_SUSPEND before
timekeeping_suspend() which is invoked by the last CPU. In the resume
case it set back to SYSTEM_RUNNING after timekeeping_resume() which is
invoked by the first CPU in the resume case. The other CPUs will block
on tick_freeze_lock.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[bigeasy: cover s2idle in tick_freeze() / tick_unfreeze()]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-05-27 11:55:02 +02:00
Dan Carpenter
227abcc6da staging: kernel.h: Prevent macro expantion bug in container_of_safe()
There aren't many users of this so it doesn't cause a problem, but we
obviously want to use "__mptr" here instead of "ptr" to prevent the
parameter from being executed twice.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: NeilBrown <neilb@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-26 09:17:34 +02:00
NeilBrown
05e6557b8e staging: lustre: add container_of_safe()
Luster has a container_of0() function which is similar to
container_of() but passes an IS_ERR_OR_NULL() pointer through
unchanged.
This could be generally useful: bcache at last has a similar function.

Naming is hard, but the precedent set by hlist_entry_safe() suggests
a _safe suffix might be most consistent.

So add container_of_safe() to kernel.h, and replace all occurrences of
container_of0() with one of
  - list_first_entry, list_next_entry, when that is a better fit,
  - container_of(), when the pointer is used as a validpointer in
    surrounding code,
  - container_of_safe() when there is no obviously better alternative.

Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-23 15:16:58 +02:00
Kees Cook
bc4f2f5469 taint: add taint for randstruct
Since the randstruct plugin can intentionally produce extremely unusual
kernel structure layouts (even performance pathological ones), some
maintainers want to be able to trivially determine if an Oops is coming
from a randstruct-built kernel, so as to keep their sanity when
debugging.  This adds the new flag and initializes taint_mask
immediately when built with randstruct.

Link: http://lkml.kernel.org/r/1519084390-43867-4-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:35 -07:00
Kees Cook
47d4b263a2 taint: convert to indexed initialization
This converts to using indexed initializers instead of comments, adds a
comment on why the taint flags can't be an enum, and make sure that no
one forgets to update the taint_flags when adding new bits.

Link: http://lkml.kernel.org/r/1519084390-43867-2-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:34 -07:00
Andrei Vagin
d1be35cb6f proc: add seq_put_decimal_ull_width to speed up /proc/pid/smaps
seq_put_decimal_ull_w(m, str, val, width) prints a decimal number with a
specified minimal field width.

It is equivalent of seq_printf(m, "%s%*d", str, width, val), but it
works much faster.

== test_smaps.py
  num = 0
  with open("/proc/1/smaps") as f:
          for x in xrange(10000):
                  data = f.read()
                  f.seek(0, 0)
==

== Before patch ==
  $ time python test_smaps.py
  real    0m4.593s
  user    0m0.398s
  sys     0m4.158s

== After patch ==
  $ time python test_smaps.py
  real    0m3.828s
  user    0m0.413s
  sys     0m3.408s

$ perf -g record python test_smaps.py
== Before patch ==
-   79.01%     3.36%  python   [kernel.kallsyms]    [k] show_smap.isra.33
   - 75.65% show_smap.isra.33
      + 48.85% seq_printf
      + 15.75% __walk_page_range
      + 9.70% show_map_vma.isra.23
        0.61% seq_puts

== After patch ==
-   75.51%     4.62%  python   [kernel.kallsyms]    [k] show_smap.isra.33
   - 70.88% show_smap.isra.33
      + 24.82% seq_put_decimal_ull_w
      + 19.78% __walk_page_range
      + 12.74% seq_printf
      + 11.08% show_map_vma.isra.23
      + 1.68% seq_puts

[akpm@linux-foundation.org: fix drivers/of/unittest.c build]
Link: http://lkml.kernel.org/r/20180212074931.7227-1-avagin@openvz.org
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:33 -07:00
Linus Torvalds
e9092d0d97 Fix subtle macro variable shadowing in min_not_zero()
Commit 3c8ba0d61d ("kernel.h: Retain constant expression output for
max()/min()") rewrote our min/max macros to be very clever, but in the
meantime resurrected a variable name shadow issue that we had had
previously fixed in commit 589a9785ee ("min/max: remove sparse
warnings when they're nested").

That commit talks about the sparse warnings that this shadowing causes,
which we ignored as just a minor annoyance.  But it turns out that the
sparse warning is the least of our problems.  We actually have a real
bug due to the shadowing through the interaction with "min_not_zero()",
which ends up doing

   min(__x, __y)

internally, and then the new declaration of "__x" and "__y" as new
variables in __cmp_once() results in a complete mess of an expression,
and "min_not_zero()" doesn't work at all.

For some odd reason, this only ever caused (reported) problems on s390,
even though it is a generic issue and most of the (obviously successful)
testing of the problematic commit had happened on other architectures.

Quoting Sebastian Ott:
 "What happened is that the bio build by the partition detection code
  was attempted to be split by the block layer because the block queue
  had a max_sector setting of 0. blk_queue_max_hw_sectors uses
  min_not_zero."

So re-introduce the use of __UNIQUE_ID() to make sure that the min/max
macros do not have these kinds of clashes.

[ That said, __UNIQUE_ID() itself has several issues that make it less
  than wonderful.

  In particular, the "uniqueness" has a fallback on the line number,
  which means that it's not actually unique in more complex cases if you
  don't build with gcc or clang (which have working unique counters that
  aren't tied to line numbers).

  That historical broken fallback also means that we have that pointless
  "prefix" argument that doesn't actually make much sense _except_ for
  the known-broken case. Oh well. ]

Fixes: 3c8ba0d61d ("kernel.h: Retain constant expression output for max()/min()")
Reported-and-tested-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-09 10:34:07 -07:00
Kees Cook
3c8ba0d61d kernel.h: Retain constant expression output for max()/min()
In the effort to remove all VLAs from the kernel[1], it is desirable to
build with -Wvla.  However, this warning is overly pessimistic, in that
it is only happy with stack array sizes that are declared as constant
expressions, and not constant values.  One case of this is the
evaluation of the max() macro which, due to its construction, ends up
converting constant expression arguments into a constant value result.

All attempts to rewrite this macro with __builtin_constant_p() failed
with older compilers (e.g.  gcc 4.4)[2].  However, Martin Uecker,
constructed[3] a mind-shattering solution that works everywhere.
Cthulhu fhtagn!

This patch updates the min()/max() macros to evaluate to a constant
expression when called on constant expression arguments.  This removes
several false-positive stack VLA warnings from an x86 allmodconfig build
when -Wvla is added:

  $ diff -u before.txt after.txt | grep ^-
  -drivers/input/touchscreen/cyttsp4_core.c:871:2: warning: ISO C90 forbids variable length array ‘ids’ [-Wvla]
  -fs/btrfs/tree-checker.c:344:4: warning: ISO C90 forbids variable length array ‘namebuf’ [-Wvla]
  -lib/vsprintf.c:747:2: warning: ISO C90 forbids variable length array ‘sym’ [-Wvla]
  -net/ipv4/proc.c:403:2: warning: ISO C90 forbids variable length array ‘buff’ [-Wvla]
  -net/ipv6/proc.c:198:2: warning: ISO C90 forbids variable length array ‘buff’ [-Wvla]
  -net/ipv6/proc.c:218:2: warning: ISO C90 forbids variable length array ‘buff64’ [-Wvla]

This also updates two cases where different enums were being compared
and explicitly casts them to int (which matches the old side-effect of
the single-evaluation code): one in tpm/tpm_tis_core.h, and one in
drm/drm_color_mgmt.c.

 [1] https://lkml.org/lkml/2018/3/7/621
 [2] https://lkml.org/lkml/2018/3/10/170
 [3] https://lkml.org/lkml/2018/3/20/845

Co-Developed-by: Linus Torvalds <torvalds@linux-foundation.org>
Co-Developed-by: Martin Uecker <Martin.Uecker@med.uni-goettingen.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05 14:17:16 -07:00
Linus Torvalds
df34df483a Staging/IIO patches for 4.17-rc1
Here is the big set of Staging/IIO driver patches for 4.17-rc1.
 
 It is a lot, over 500 changes, but not huge by previous kernel release
 standards.  We deleted more lines than we added again (27k added vs. 91k
 remvoed), thanks to finally being able to delete the IRDA drivers and
 networking code.
 
 We also deleted the ccree crypto driver, but that's coming back in
 through the crypto tree to you, in a much cleaned-up form.
 
 Added this round is at lot of "mt7621" device support, which is for an
 embedded device that Neil Brown cares about, and of course a handful of
 new IIO drivers as well.
 
 And finally, the fsl-mc core code moved out of the staging tree to the
 "real" part of the kernel, which is nice to see happen as well.
 
 Full details are in the shortlog, which has all of the tiny cleanup
 patches described.
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging/IIO updates from Greg KH:
 "Here is the big set of Staging/IIO driver patches for 4.17-rc1.

  It is a lot, over 500 changes, but not huge by previous kernel release
  standards. We deleted more lines than we added again (27k added vs.
  91k remvoed), thanks to finally being able to delete the IRDA drivers
  and networking code.

  We also deleted the ccree crypto driver, but that's coming back in
  through the crypto tree to you, in a much cleaned-up form.

  Added this round is at lot of "mt7621" device support, which is for an
  embedded device that Neil Brown cares about, and of course a handful
  of new IIO drivers as well.

  And finally, the fsl-mc core code moved out of the staging tree to the
  "real" part of the kernel, which is nice to see happen as well.

  Full details are in the shortlog, which has all of the tiny cleanup
  patches described.

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

* tag 'staging-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (579 commits)
  staging: rtl8723bs: Remove yield call, replace with cond_resched()
  staging: rtl8723bs: Replace yield() call with cond_resched()
  staging: rtl8723bs: Remove unecessary newlines from 'odm.h'.
  staging: rtl8723bs: Rework 'struct _ODM_Phy_Status_Info_' coding style.
  staging: rtl8723bs: Rework 'struct _ODM_Per_Pkt_Info_' coding style.
  staging: rtl8723bs: Replace NULL pointer comparison with '!'.
  staging: rtl8723bs: Factor out rtl8723bs_recv_tasklet() sections.
  staging: rtl8723bs: Fix function signature that goes over 80 characters.
  staging: rtl8723bs: Fix lines too long in update_recvframe_attrib().
  staging: rtl8723bs: Remove unnecessary blank lines in 'rtl8723bs_recv.c'.
  staging: rtl8723bs: Change camel case to snake case in 'rtl8723bs_recv.c'.
  staging: rtl8723bs: Add missing braces in else statement.
  staging: rtl8723bs: Add spaces around ternary operators.
  staging: rtl8723bs: Fix lines with trailing open parentheses.
  staging: rtl8723bs: Remove unnecessary length #define's.
  staging: rtl8723bs: Fix IEEE80211 authentication algorithm constants.
  staging: rtl8723bs: Fix alignment in rtw_wx_set_auth().
  staging: rtl8723bs: Remove braces from single statement conditionals.
  staging: rtl8723bs: Remove unecessary braces from switch statement.
  staging: rtl8723bs: Fix newlines in rtw_wx_set_auth().
  ...
2018-04-04 18:56:27 -07:00
Alexei Starovoitov
cf14f27f82 macro: introduce COUNT_ARGS() macro
move COUNT_ARGS() macro from apparmor to generic header and extend it
to count till twelve.

COUNT() was an alternative name for this logic, but it's used for
different purpose in many other places.

Similarly for CONCATENATE() macro.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-28 22:55:19 +02:00
Greg Kroah-Hartman
73709e1af5 Merge 4.16-rc6 into staging-next
We want the staging fixes in here as well to handle merge/test issues.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-19 06:47:01 +01:00
Josh Poimboeuf
9fbcc57aa1 extable: Make init_kernel_text() global
Convert init_kernel_text() to a global function and use it in a few
places instead of manually comparing _sinittext and _einittext.

Note that kallsyms.h has a very similar function called
is_kernel_inittext(), but its end check is inclusive.  I'm not sure
whether that's intentional behavior, so I didn't touch it.

Suggested-by: Jason Baron <jbaron@akamai.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/4335d02be8d45ca7d265d2f174251d0b7ee6c5fd.1519051220.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-21 16:54:06 +01:00
Crt Mori
47a3616348 lib: Add strongly typed 64bit int_sqrt
There is no option to perform 64bit integer sqrt on 32bit platform.
Added stronger typed int_sqrt64 enables the 64bit calculations to
be performed on 32bit platforms. Using same algorithm as int_sqrt()
with strong typing provides enough precision also on 32bit platforms,
but it sacrifices some performance. In case values are smaller than
ULONG_MAX the standard int_sqrt is used for calculation to maximize the
performance due to more native calculations.

Signed-off-by: Crt Mori <cmo@melexis.com>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-02-04 10:17:21 +00:00
Borislav Petkov
4efb442cc1 kernel/panic.c: add TAINT_AUX
This is the gist of a patch which we've been forward-porting in our
kernels for a long time now and it probably would make a good sense to
have such TAINT_AUX flag upstream which can be used by each distro etc,
how they see fit.  This way, we won't need to forward-port a distro-only
version indefinitely.

Add an auxiliary taint flag to be used by distros and others.  This
obviates the need to forward-port whatever internal solutions people
have in favor of a single flag which they can map arbitrarily to a
definition of their pleasing.

The "X" mnemonic could also mean eXternal, which would be taint from a
distro or something else but not the upstream kernel.  We will use it to
mark modules for which we don't provide support.  I.e., a really
eXternal module.

Link: http://lkml.kernel.org/r/20170911134533.dp5mtyku5bongx4c@pd.tnic
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:04 -08:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Randy Dunlap
e8c97af0c1 linux/kernel.h: add/correct kernel-doc notation
Add kernel-doc notation for some macros.  Correct kernel-doc comments &
typos for a few macros.

Link: http://lkml.kernel.org/r/76fa1403-1511-be4c-e9c4-456b43edfad3@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-13 16:18:33 -07:00
Masahiro Yamada
604df32236 linux/kernel.h: move DIV_ROUND_DOWN_ULL() macro
This macro is useful to avoid link error on 32-bit systems.

We have the same definition in two drivers, so move it to
include/linux/kernel.h

While we are here, refactor DIV_ROUND_UP_ULL() by using
DIV_ROUND_DOWN_ULL().

Link: http://lkml.kernel.org/r/1500945156-12907-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Mark Brown <broonie@kernel.org>
Cc: Cyrille Pitchen <cyrille.pitchen@wedev4u.fr>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Boris Brezillon <boris.brezillon@free-electrons.com>
Cc: Marek Vasut <marek.vasut@gmail.com>
Cc: Brian Norris <computersforpeace@gmail.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-08 18:26:47 -07:00
Kees Cook
7a46ec0e2f locking/refcounts, x86/asm: Implement fast refcount overflow protection
This implements refcount_t overflow protection on x86 without a noticeable
performance impact, though without the fuller checking of REFCOUNT_FULL.

This is done by duplicating the existing atomic_t refcount implementation
but with normally a single instruction added to detect if the refcount
has gone negative (e.g. wrapped past INT_MAX or below zero). When detected,
the handler saturates the refcount_t to INT_MIN / 2. With this overflow
protection, the erroneous reference release that would follow a wrap back
to zero is blocked from happening, avoiding the class of refcount-overflow
use-after-free vulnerabilities entirely.

Only the overflow case of refcounting can be perfectly protected, since
it can be detected and stopped before the reference is freed and left to
be abused by an attacker. There isn't a way to block early decrements,
and while REFCOUNT_FULL stops increment-from-zero cases (which would
be the state _after_ an early decrement and stops potential double-free
conditions), this fast implementation does not, since it would require
the more expensive cmpxchg loops. Since the overflow case is much more
common (e.g. missing a "put" during an error path), this protection
provides real-world protection. For example, the two public refcount
overflow use-after-free exploits published in 2016 would have been
rendered unexploitable:

  http://perception-point.io/2016/01/14/analysis-and-exploitation-of-a-linux-kernel-vulnerability-cve-2016-0728/

  http://cyseclabs.com/page?n=02012016

This implementation does, however, notice an unchecked decrement to zero
(i.e. caller used refcount_dec() instead of refcount_dec_and_test() and it
resulted in a zero). Decrements under zero are noticed (since they will
have resulted in a negative value), though this only indicates that a
use-after-free may have already happened. Such notifications are likely
avoidable by an attacker that has already exploited a use-after-free
vulnerability, but it's better to have them reported than allow such
conditions to remain universally silent.

On first overflow detection, the refcount value is reset to INT_MIN / 2
(which serves as a saturation value) and a report and stack trace are
produced. When operations detect only negative value results (such as
changing an already saturated value), saturation still happens but no
notification is performed (since the value was already saturated).

On the matter of races, since the entire range beyond INT_MAX but before
0 is negative, every operation at INT_MIN / 2 will trap, leaving no
overflow-only race condition.

As for performance, this implementation adds a single "js" instruction
to the regular execution flow of a copy of the standard atomic_t refcount
operations. (The non-"and_test" refcount_dec() function, which is uncommon
in regular refcount design patterns, has an additional "jz" instruction
to detect reaching exactly zero.) Since this is a forward jump, it is by
default the non-predicted path, which will be reinforced by dynamic branch
prediction. The result is this protection having virtually no measurable
change in performance over standard atomic_t operations. The error path,
located in .text.unlikely, saves the refcount location and then uses UD0
to fire a refcount exception handler, which resets the refcount, handles
reporting, and returns to regular execution. This keeps the changes to
.text size minimal, avoiding return jumps and open-coded calls to the
error reporting routine.

Example assembly comparison:

refcount_inc() before:

  .text:
  ffffffff81546149:       f0 ff 45 f4             lock incl -0xc(%rbp)

refcount_inc() after:

  .text:
  ffffffff81546149:       f0 ff 45 f4             lock incl -0xc(%rbp)
  ffffffff8154614d:       0f 88 80 d5 17 00       js     ffffffff816c36d3
  ...
  .text.unlikely:
  ffffffff816c36d3:       48 8d 4d f4             lea    -0xc(%rbp),%rcx
  ffffffff816c36d7:       0f ff                   (bad)

These are the cycle counts comparing a loop of refcount_inc() from 1
to INT_MAX and back down to 0 (via refcount_dec_and_test()), between
unprotected refcount_t (atomic_t), fully protected REFCOUNT_FULL
(refcount_t-full), and this overflow-protected refcount (refcount_t-fast):

  2147483646 refcount_inc()s and 2147483647 refcount_dec_and_test()s:
		    cycles		protections
  atomic_t           82249267387	none
  refcount_t-fast    82211446892	overflow, untested dec-to-zero
  refcount_t-full   144814735193	overflow, untested dec-to-zero, inc-from-zero

This code is a modified version of the x86 PAX_REFCOUNT atomic_t
overflow defense from the last public patch of PaX/grsecurity, based
on my understanding of the code. Changes or omissions from the original
code are mine and don't reflect the original grsecurity/PaX code. Thanks
to PaX Team for various suggestions for improvement for repurposing this
code to be a refcount-only protection.

Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Hans Liljestrand <ishkamiel@gmail.com>
Cc: James Bottomley <James.Bottomley@hansenpartnership.com>
Cc: Jann Horn <jannh@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Serge E. Hallyn <serge@hallyn.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: arozansk@redhat.com
Cc: axboe@kernel.dk
Cc: kernel-hardening@lists.openwall.com
Cc: linux-arch <linux-arch@vger.kernel.org>
Link: http://lkml.kernel.org/r/20170815161924.GA133115@beast
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-17 10:40:26 +02:00
Ian Abbott
c7acec713d kernel.h: handle pointers to arrays better in container_of()
If the first parameter of container_of() is a pointer to a
non-const-qualified array type (and the third parameter names a
non-const-qualified array member), the local variable __mptr will be
defined with a const-qualified array type.  In ISO C, these types are
incompatible.  They work as expected in GNU C, but some versions will
issue warnings.  For example, GCC 4.9 produces the warning
"initialization from incompatible pointer type".

Here is an example of where the problem occurs:

-------------------------------------------------------
   #include <linux/kernel.h>
   #include <linux/module.h>

  MODULE_LICENSE("GPL");

  struct st {
  	int a;
  	char b[16];
  };

  static int __init example_init(void) {
  	struct st t = { .a = 101, .b = "hello" };
  	char (*p)[16] = &t.b;
  	struct st *x = container_of(p, struct st, b);
  	printk(KERN_DEBUG "%p %p\n", (void *)&t, (void *)x);
  	return 0;
  }

  static void __exit example_exit(void) {
  }

  module_init(example_init);
  module_exit(example_exit);
-------------------------------------------------------

Building the module with gcc-4.9 results in these warnings (where '{m}'
is the module source and '{k}' is the kernel source):

-------------------------------------------------------
  In file included from {m}/example.c:1:0:
  {m}/example.c: In function `example_init':
  {k}/include/linux/kernel.h:854:48: warning: initialization from incompatible pointer type
    const typeof( ((type *)0)->member ) *__mptr = (ptr); \
                                                  ^
  {m}/example.c:14:17: note: in expansion of macro `container_of'
    struct st *x = container_of(p, struct st, b);
                   ^
  {k}/include/linux/kernel.h:854:48: warning: (near initialization for `x')
    const typeof( ((type *)0)->member ) *__mptr = (ptr); \
                                                  ^
  {m}/example.c:14:17: note: in expansion of macro `container_of'
    struct st *x = container_of(p, struct st, b);
                   ^
-------------------------------------------------------

Replace the type checking performed by the macro to avoid these
warnings.  Make sure `*(ptr)` either has type compatible with the
member, or has type compatible with `void`, ignoring qualifiers.  Raise
compiler errors if this is not true.  This is stronger than the previous
behaviour, which only resulted in compiler warnings for a type mismatch.

[arnd@arndb.de: fix new warnings for container_of()]
  Link: http://lkml.kernel.org/r/20170620200940.90557-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/20170525120316.24473-7-abbotti@mev.co.uk
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Johannes Berg <johannes.berg@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-12 16:25:59 -07:00
Thomas Gleixner
69a78ff226 init: Introduce SYSTEM_SCHEDULING state
might_sleep() debugging and smp_processor_id() debugging should be active
right after the scheduler starts working. The init task can invoke
smp_processor_id() from preemptible context as it is pinned on the boot cpu
until sched_smp_init() removes the pinning and lets it schedule on all non
isolated cpus.

Add a new state which allows to enable those checks earlier and add it to
the xen do_poweroff() function.

No functional change.

Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170516184736.196214622@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-23 10:01:38 +02:00
Linus Torvalds
5a0387a8a8 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu:
 "Here is the crypto update for 4.12:

  API:
   - Add batch registration for acomp/scomp
   - Change acomp testing to non-unique compressed result
   - Extend algorithm name limit to 128 bytes
   - Require setkey before accept(2) in algif_aead

  Algorithms:
   - Add support for deflate rfc1950 (zlib)

  Drivers:
   - Add accelerated crct10dif for powerpc
   - Add crc32 in stm32
   - Add sha384/sha512 in ccp
   - Add 3des/gcm(aes) for v5 devices in ccp
   - Add Queue Interface (QI) backend support in caam
   - Add new Exynos RNG driver
   - Add ThunderX ZIP driver
   - Add driver for hardware random generator on MT7623 SoC"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (101 commits)
  crypto: stm32 - Fix OF module alias information
  crypto: algif_aead - Require setkey before accept(2)
  crypto: scomp - add support for deflate rfc1950 (zlib)
  crypto: scomp - allow registration of multiple scomps
  crypto: ccp - Change ISR handler method for a v5 CCP
  crypto: ccp - Change ISR handler method for a v3 CCP
  crypto: crypto4xx - rename ce_ring_contol to ce_ring_control
  crypto: testmgr - Allow ecb(cipher_null) in FIPS mode
  Revert "crypto: arm64/sha - Add constant operand modifier to ASM_EXPORT"
  crypto: ccp - Disable interrupts early on unload
  crypto: ccp - Use only the relevant interrupt bits
  hwrng: mtk - Add driver for hardware random generator on MT7623 SoC
  dt-bindings: hwrng: Add Mediatek hardware random generator bindings
  crypto: crct10dif-vpmsum - Fix missing preempt_disable()
  crypto: testmgr - replace compression known answer test
  crypto: acomp - allow registration of multiple acomps
  hwrng: n2 - Use devm_kcalloc() in n2rng_probe()
  crypto: chcr - Fix error handling related to 'chcr_alloc_shash'
  padata: get_next is never NULL
  crypto: exynos - Add new Exynos RNG driver
  ...
2017-05-02 15:53:46 -07:00
Krzysztof Kozlowski
ed067d4a85 linux/kernel.h: Add ALIGN_DOWN macro
Few parts of kernel define their own macro for aligning down so provide
a common define for this, with the same usage and assumptions as existing
ALIGN.

Convert also three existing implementations to this one.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-04-21 20:30:44 +08:00
Baoquan He
f51b17c8d9 boot/param: Move next_arg() function to lib/cmdline.c for later reuse
next_arg() will be used to parse boot parameters in the x86/boot/compressed code,
so move it to lib/cmdline.c for better code reuse.

No change in functionality.

Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Cc: Jens Axboe <axboe@fb.com>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Johannes Berg <johannes.berg@intel.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dan.j.williams@intel.com
Cc: dave.jiang@intel.com
Cc: dyoung@redhat.com
Cc: keescook@chromium.org
Cc: zijun_hu <zijun_hu@htc.com>
Link: http://lkml.kernel.org/r/1492436099-4017-2-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-18 10:37:13 +02:00
Niklas Söderlund
4f5901f5a6 linux/kernel.h: fix DIV_ROUND_CLOSEST to support negative divisors
While working on a thermal driver I encounter a scenario where the
divisor could be negative, instead of adding local code to handle this I
though I first try to add support for this in DIV_ROUND_CLOSEST.

Add support to DIV_ROUND_CLOSEST for negative divisors if both dividend
and divisor variable types are signed.  This should not alter current
behavior for users of the macro as previously negative divisors where
not supported.

Before:

DIV_ROUND_CLOSEST(  59,  4) =  15
DIV_ROUND_CLOSEST(  59, -4) = -14
DIV_ROUND_CLOSEST( -59,  4) = -15
DIV_ROUND_CLOSEST( -59, -4) =  14

After:

DIV_ROUND_CLOSEST(  59,  4) =  15
DIV_ROUND_CLOSEST(  59, -4) = -15
DIV_ROUND_CLOSEST( -59,  4) = -15
DIV_ROUND_CLOSEST( -59, -4) =  15

[akpm@linux-foundation.org: fix comment, per Guenter]
Link: http://lkml.kernel.org/r/20161222102217.29011-1-niklas.soderlund+renesas@ragnatech.se
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:57 -08:00
Larry Finger
5eb7c0d04f taint/module: Fix problems when out-of-kernel driver defines true or false
Commit 7fd8329ba5 ("taint/module: Clean up global and module taint
flags handling") used the key words true and false as character members
of a new struct. These names cause problems when out-of-kernel modules
such as VirtualBox include their own definitions of true and false.

Fixes: 7fd8329ba5 ("taint/module: Clean up global and module taint flags handling")
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Reported-by: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jessica Yu <jeyu@redhat.com>
2017-01-17 10:56:45 -08:00
Linus Torvalds
4d98ead183 Modules updates for v4.10
Summary of modules changes for the 4.10 merge window:
 
 * The rodata= cmdline parameter has been extended to additionally
   apply to module mappings
 
 * Fix a hard to hit race between module loader error/clean up
   handling and ftrace registration
 
 * Some code cleanups, notably panic.c and modules code use a
   unified taint_flags table now. This is much cleaner than
   duplicating the taint flag code in modules.c
 
 Signed-off-by: Jessica Yu <jeyu@redhat.com>
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Merge tag 'modules-for-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux

Pull modules updates from Jessica Yu:
 "Summary of modules changes for the 4.10 merge window:

   - The rodata= cmdline parameter has been extended to additionally
     apply to module mappings

   - Fix a hard to hit race between module loader error/clean up
     handling and ftrace registration

   - Some code cleanups, notably panic.c and modules code use a unified
     taint_flags table now. This is much cleaner than duplicating the
     taint flag code in modules.c"

* tag 'modules-for-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  module: fix DEBUG_SET_MODULE_RONX typo
  module: extend 'rodata=off' boot cmdline parameter to module mappings
  module: Fix a comment above strong_try_module_get()
  module: When modifying a module's text ignore modules which are going away too
  module: Ensure a module's state is set accordingly during module coming cleanup code
  module: remove trailing whitespace
  taint/module: Clean up global and module taint flags handling
  modpost: free allocated memory
2016-12-14 20:12:43 -08:00
Linus Torvalds
e6efef7260 Merge branch 'for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
Pull percpu update from Tejun Heo:
 "This includes just one patch to reject non-power-of-2 alignments and
  trigger warning. Interestingly, this actually caught a bug in XEN
  ARM64"

* 'for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu: ensure the requested alignment is power of two
2016-12-13 12:34:47 -08:00
Petr Mladek
7fd8329ba5 taint/module: Clean up global and module taint flags handling
The commit 66cc69e34e ("Fix: module signature vs tracepoints:
add new TAINT_UNSIGNED_MODULE") updated module_taint_flags() to
potentially print one more character. But it did not increase the
size of the corresponding buffers in m_show() and print_modules().

We have recently done the same mistake when adding a taint flag
for livepatching, see
https://lkml.kernel.org/r/cfba2c823bb984690b73572aaae1db596b54a082.1472137475.git.jpoimboe@redhat.com

Also struct module uses an incompatible type for mod-taints flags.
It survived from the commit 2bc2d61a96 ("[PATCH] list module
taint flags in Oops/panic"). There was used "int" for the global taint
flags at these times. But only the global tain flags was later changed
to "unsigned long" by the commit 25ddbb18aa ("Make the taint
flags reliable").

This patch defines TAINT_FLAGS_COUNT that can be used to create
arrays and buffers of the right size. Note that we could not use
enum because the taint flag indexes are used also in assembly code.

Then it reworks the table that describes the taint flags. The TAINT_*
numbers can be used as the index. Instead, we add information
if the taint flag is also shown per-module.

Finally, it uses "unsigned long", bit operations, and the updated
taint_flags table also for mod->taints.

It is not optimal because only few taint flags can be printed by
module_taint_flags(). But better be on the safe side. IMHO, it is
not worth the optimization and this is a good compromise.

Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: http://lkml.kernel.org/r/1474458442-21581-1-git-send-email-pmladek@suse.com
[jeyu@redhat.com: fix broken lkml link in changelog]
Signed-off-by: Jessica Yu <jeyu@redhat.com>
2016-11-26 11:18:01 -08:00
Christoph Hellwig
d38499530e fs: decouple READ and WRITE from the block layer ops
Move READ and WRITE to kernel.h and don't define them in terms of block
layer ops; they are our generic data direction indicators these days
and have no more resemblance with the block layer ops.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-01 09:43:26 -06:00
zijun_hu
3ca45a46f8 percpu: ensure the requested alignment is power of two
The percpu allocator expectedly assumes that the requested alignment
is power of two but hasn't been veryfing the input.  If the specified
alignment isn't power of two, the allocator can malfunction.  Add the
sanity check.

The following is detailed analysis of the effects of alignments which
aren't power of two.

 The alignment must be a even at least since the LSB of a chunk->map
 element is used as free/in-use flag of a area; besides, the alignment
 must be a power of 2 too since ALIGN() doesn't work well for other
 alignment always but is adopted by pcpu_fit_in_area().  IOW, the
 current allocator only works well for a power of 2 aligned area
 allocation.

 See below opposite example for why an odd alignment doesn't work.
 Let's assume area [16, 36) is free but its previous one is in-use, we
 want to allocate a @size == 8 and @align == 7 area.  The larger area
 [16, 36) is split to three areas [16, 21), [21, 29), [29, 36)
 eventually.  However, due to the usage for a chunk->map element, the
 actual offset of the aim area [21, 29) is 21 but is recorded in
 relevant element as 20; moreover, the residual tail free area [29,
 36) is mistook as in-use and is lost silently

 Unlike macro roundup(), ALIGN(x, a) doesn't work if @a isn't a power
 of 2 for example, roundup(10, 6) == 12 but ALIGN(10, 6) == 10, and
 the latter result isn't desired obviously.

tj: Code style and patch description updates.

Signed-off-by: zijun_hu <zijun_hu@htc.com>
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2016-10-19 13:53:02 -04:00
Johannes Berg
589a9785ee min/max: remove sparse warnings when they're nested
Currently, when min/max are nested within themselves, sparse will warn:

    warning: symbol '_min1' shadows an earlier one
    originally declared here
    warning: symbol '_min1' shadows an earlier one
    originally declared here
    warning: symbol '_min2' shadows an earlier one
    originally declared here

This also immediately happens when min3() or max3() are used.

Since sparse implements __COUNTER__, we can use __UNIQUE_ID() to
generate unique variable names, avoiding this.

Link: http://lkml.kernel.org/r/1471519773-29882-1-git-send-email-johannes@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-07 18:46:30 -07:00
Peter Zijlstra
9af6528ee9 sched/core: Optimize __schedule()
Oleg noted that by making do_exit() use __schedule() for the TASK_DEAD
context switch, we can avoid the TASK_DEAD special case currently in
__schedule() because that avoids the extra preempt_disable() from
schedule().

In order to facilitate this, create a do_task_dead() helper which we
place in the scheduler code, such that it can access __schedule().

Also add some __noreturn annotations to the functions, there's no
coming back from do_exit().

Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Cheng Chao <cs.os.kernel@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akpm@linux-foundation.org
Cc: chris@chris-wilson.co.uk
Cc: tj@kernel.org
Link: http://lkml.kernel.org/r/20160913163729.GB5012@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-22 14:53:45 +02:00
Luis de Bethencourt
9d5059c959 dynamic_debug: only add header when used
kernel.h header doesn't directly use dynamic debug, instead we can
include it in module.c (which used it via kernel.h).  printk.h only uses
it if CONFIG_DYNAMIC_DEBUG is on, changing the inclusion to only happen
in that case.

Link: http://lkml.kernel.org/r/1468429793-16917-1-git-send-email-luisbg@osg.samsung.com
[luisbg@osg.samsung.com: include dynamic_debug.h in drb_int.h]
  Link: http://lkml.kernel.org/r/1468447828-18558-2-git-send-email-luisbg@osg.samsung.com
Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02 19:35:03 -04:00
Daniel Bristot de Oliveira
088e9d253d rcu: sysctl: Panic on RCU Stall
It is not always easy to determine the cause of an RCU stall just by
analysing the RCU stall messages, mainly when the problem is caused
by the indirect starvation of rcu threads. For example, when preempt_rcu
is not awakened due to the starvation of a timer softirq.

We have been hard coding panic() in the RCU stall functions for
some time while testing the kernel-rt. But this is not possible in
some scenarios, like when supporting customers.

This patch implements the sysctl kernel.panic_on_rcu_stall. If
set to 1, the system will panic() when an RCU stall takes place,
enabling the capture of a vmcore. The vmcore provides a way to analyze
all kernel/tasks states, helping out to point to the culprit and the
solution for the stall.

The kernel.panic_on_rcu_stall sysctl is disabled by default.

Changes from v1:
- Fixed a typo in the git log
- The if(sysctl_panic_on_rcu_stall) panic() is in a static function
- Fixed the CONFIG_TINY_RCU compilation issue
- The var sysctl_panic_on_rcu_stall is now __read_mostly

Cc: Jonathan Corbet <corbet@lwn.net>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Reviewed-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Tested-by: "Luis Claudio R. Goncalves" <lgoncalv@redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2016-06-15 16:00:05 -07:00
Linus Torvalds
2f37dd131c Staging and IIO driver update for 4.7-rc1
Here's the big staging and iio driver update for 4.7-rc1.
 
 I think we almost broke even with this release, only adding a few more
 lines than we removed, which isn't bad overall given that there's a
 bunch of new iio drivers added.  The Lustre developers seem to have
 woken up from their sleep and have been doing a great job in cleaning up
 the code and pruning unused or old cruft, the filesystem is almost
 readable :)
 
 Other than that, just a lot of basic coding style cleanups in the churn.
 All have been in linux-next for a while with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging and IIO driver updates from Greg KH:
 "Here's the big staging and iio driver update for 4.7-rc1.

  I think we almost broke even with this release, only adding a few more
  lines than we removed, which isn't bad overall given that there's a
  bunch of new iio drivers added.

  The Lustre developers seem to have woken up from their sleep and have
  been doing a great job in cleaning up the code and pruning unused or
  old cruft, the filesystem is almost readable :)

  Other than that, just a lot of basic coding style cleanups in the
  churn.  All have been in linux-next for a while with no reported
  issues"

* tag 'staging-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (938 commits)
  Staging: emxx_udc: emxx_udc: fixed coding style issue
  staging/gdm724x: fix "alignment should match open parenthesis" issues
  staging/gdm724x: Fix avoid CamelCase
  staging: unisys: rename misleading var ii with frag
  staging: unisys: visorhba: switch success handling to error handling
  staging: unisys: visorhba: main path needs to flow down the left margin
  staging: unisys: visorinput: handle_locking_key() simplifications
  staging: unisys: visorhba: fail gracefully for thread creation failures
  staging: unisys: visornic: comment restructuring and removing bad diction
  staging: unisys: fix format string %Lx to %llx for u64
  staging: unisys: remove unused struct members
  staging: unisys: visorchannel: correct variable misspelling
  staging: unisys: visorhba: replace functionlike macro with function
  staging: dgnc: Need to check for NULL of ch
  staging: dgnc: remove redundant condition check
  staging: dgnc: fix 'line over 80 characters'
  staging: dgnc: clean up the dgnc_get_modem_info()
  staging: lustre: lnet: enable configuration per NI interface
  staging: lustre: o2iblnd: properly set ibr_why
  staging: lustre: o2iblnd: remove last of kiblnd_tunables_fini
  ...
2016-05-20 22:20:48 -07:00
Rasmus Villemoes
48a270554a include/linux: apply __malloc attribute
Attach the malloc attribute to a few allocation functions.  This helps
gcc generate better code by telling it that the return value doesn't
alias any existing pointers (which is even more valuable given the
pessimizations implied by -fno-strict-aliasing).

A simple example of what this allows gcc to do can be seen by looking at
the last part of drm_atomic_helper_plane_reset:

	plane->state = kzalloc(sizeof(*plane->state), GFP_KERNEL);

	if (plane->state) {
		plane->state->plane = plane;
		plane->state->rotation = BIT(DRM_ROTATE_0);
	}

which compiles to

    e8 99 bf d6 ff          callq  ffffffff8116d540 <kmem_cache_alloc_trace>
    48 85 c0                test   %rax,%rax
    48 89 83 40 02 00 00    mov    %rax,0x240(%rbx)
    74 11                   je     ffffffff814015c4 <drm_atomic_helper_plane_reset+0x64>
    48 89 18                mov    %rbx,(%rax)
    48 8b 83 40 02 00 00    mov    0x240(%rbx),%rax [*]
    c7 40 40 01 00 00 00    movl   $0x1,0x40(%rax)

With this patch applied, the instruction at [*] is elided, since the
store to plane->state->plane is known to not alter the value of
plane->state.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-19 19:12:14 -07:00
Gustavo Padovan
3ed605bc8a kernel.h: add u64_to_user_ptr()
This function had copies in 3 different files. Unify them in kernel.h.

Cc: Joe Perches <joe@perches.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Rob Clark <robdclark@gmail.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Acked-by: Daniel Vetter <daniel.vetter@intel.com>	[drm/i915/]
Acked-by: Rob Clark <robdclark@gmail.com>		[drm/msm/]
Acked-by: Lucas Stach <l.stach@pengutronix.de>		[drm/etinav/]
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-29 17:03:49 -07:00
Linus Torvalds
e46b4e2b46 Nothing major this round. Mostly small clean ups and fixes.
Some visible changes:
 
  A new flag was added to distinguish traces done in NMI context.
 
  Preempt tracer now shows functions where preemption is disabled but
  interrupts are still enabled.
 
 Other notes:
 
  Updates were done to function tracing to allow better performance
  with perf.
 
  Infrastructure code has been added to allow for a new histogram
  feature for recording live trace event histograms that can be
  configured by simple user commands. The feature itself was just
  finished, but needs a round in linux-next before being pulled.
  This only includes some infrastructure changes that will be needed.
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Merge tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "Nothing major this round.  Mostly small clean ups and fixes.

  Some visible changes:

   - A new flag was added to distinguish traces done in NMI context.

   - Preempt tracer now shows functions where preemption is disabled but
     interrupts are still enabled.

  Other notes:

   - Updates were done to function tracing to allow better performance
     with perf.

   - Infrastructure code has been added to allow for a new histogram
     feature for recording live trace event histograms that can be
     configured by simple user commands.  The feature itself was just
     finished, but needs a round in linux-next before being pulled.

     This only includes some infrastructure changes that will be needed"

* tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (22 commits)
  tracing: Record and show NMI state
  tracing: Fix trace_printk() to print when not using bprintk()
  tracing: Remove redundant reset per-CPU buff in irqsoff tracer
  x86: ftrace: Fix the misleading comment for arch/x86/kernel/ftrace.c
  tracing: Fix crash from reading trace_pipe with sendfile
  tracing: Have preempt(irqs)off trace preempt disabled functions
  tracing: Fix return while holding a lock in register_tracer()
  ftrace: Use kasprintf() in ftrace_profile_tracefs()
  ftrace: Update dynamic ftrace calls only if necessary
  ftrace: Make ftrace_hash_rec_enable return update bool
  tracing: Fix typoes in code comment and printk in trace_nop.c
  tracing, writeback: Replace cgroup path to cgroup ino
  tracing: Use flags instead of bool in trigger structure
  tracing: Add an unreg_all() callback to trigger commands
  tracing: Add needs_rec flag to event triggers
  tracing: Add a per-event-trigger 'paused' field
  tracing: Add get_syscall_name()
  tracing: Add event record param to trigger_ops.func()
  tracing: Make event trigger functions available
  tracing: Make ftrace_event_field checking functions available
  ...
2016-03-24 10:52:25 -07:00
Hidehiro Kawai
ebc41f20d7 panic: change nmi_panic from macro to function
Commit 1717f2096b ("panic, x86: Fix re-entrance problem due to panic
on NMI") and commit 58c5661f21 ("panic, x86: Allow CPUs to save
registers even if looping in NMI context") introduced nmi_panic() which
prevents concurrent/recursive execution of panic().  It also saves
registers for the crash dump on x86.

However, there are some cases where NMI handlers still use panic().
This patch set partially replaces them with nmi_panic() in those cases.

Even this patchset is applied, some NMI or similar handlers (e.g.  MCE
handler) continue to use panic().  This is because I can't test them
well and actual problems won't happen.  For example, the possibility
that normal panic and panic on MCE happen simultaneously is very low.

This patch (of 3):

Convert nmi_panic() to a proper function and export it instead of
exporting internal implementation details to modules, for obvious
reasons.

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: Javi Merino <javi.merino@arm.com>
Cc: Gobinda Charan Maji <gobinda.cemk07@gmail.com>
Cc: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Steven Rostedt (Red Hat)
3debb0a9dd tracing: Fix trace_printk() to print when not using bprintk()
The trace_printk() code will allocate extra buffers if the compile detects
that a trace_printk() is used. To do this, the format of the trace_printk()
is saved to the __trace_printk_fmt section, and if that section is bigger
than zero, the buffers are allocated (along with a message that this has
happened).

If trace_printk() uses a format that is not a constant, and thus something
not guaranteed to be around when the print happens, the compiler optimizes
the fmt out, as it is not used, and the __trace_printk_fmt section is not
filled. This means the kernel will not allocate the special buffers needed
for the trace_printk() and the trace_printk() will not write anything to the
tracing buffer.

Adding a "__used" to the variable in the __trace_printk_fmt section will
keep it around, even though it is set to NULL. This will keep the string
from being printed in the debugfs/tracing/printk_formats section as it is
not needed.

Reported-by: Vlastimil Babka <vbabka@suse.cz>
Fixes: 07d777fe8c "tracing: Add percpu buffers for trace_printk()"
Cc: stable@vger.kernel.org # v3.5+
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-22 18:02:40 -04:00
Linus Torvalds
1200b6809d Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Highlights:

   1) Support more Realtek wireless chips, from Jes Sorenson.

   2) New BPF types for per-cpu hash and arrap maps, from Alexei
      Starovoitov.

   3) Make several TCP sysctls per-namespace, from Nikolay Borisov.

   4) Allow the use of SO_REUSEPORT in order to do per-thread processing
   of incoming TCP/UDP connections.  The muxing can be done using a
   BPF program which hashes the incoming packet.  From Craig Gallek.

   5) Add a multiplexer for TCP streams, to provide a messaged based
      interface.  BPF programs can be used to determine the message
      boundaries.  From Tom Herbert.

   6) Add 802.1AE MACSEC support, from Sabrina Dubroca.

   7) Avoid factorial complexity when taking down an inetdev interface
      with lots of configured addresses.  We were doing things like
      traversing the entire address less for each address removed, and
      flushing the entire netfilter conntrack table for every address as
      well.

   8) Add and use SKB bulk free infrastructure, from Jesper Brouer.

   9) Allow offloading u32 classifiers to hardware, and implement for
      ixgbe, from John Fastabend.

  10) Allow configuring IRQ coalescing parameters on a per-queue basis,
      from Kan Liang.

  11) Extend ethtool so that larger link mode masks can be supported.
      From David Decotigny.

  12) Introduce devlink, which can be used to configure port link types
      (ethernet vs Infiniband, etc.), port splitting, and switch device
      level attributes as a whole.  From Jiri Pirko.

  13) Hardware offload support for flower classifiers, from Amir Vadai.

  14) Add "Local Checksum Offload".  Basically, for a tunneled packet
      the checksum of the outer header is 'constant' (because with the
      checksum field filled into the inner protocol header, the payload
      of the outer frame checksums to 'zero'), and we can take advantage
      of that in various ways.  From Edward Cree"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1548 commits)
  bonding: fix bond_get_stats()
  net: bcmgenet: fix dma api length mismatch
  net/mlx4_core: Fix backward compatibility on VFs
  phy: mdio-thunder: Fix some Kconfig typos
  lan78xx: add ndo_get_stats64
  lan78xx: handle statistics counter rollover
  RDS: TCP: Remove unused constant
  RDS: TCP: Add sysctl tunables for sndbuf/rcvbuf on rds-tcp socket
  net: smc911x: convert pxa dma to dmaengine
  team: remove duplicate set of flag IFF_MULTICAST
  bonding: remove duplicate set of flag IFF_MULTICAST
  net: fix a comment typo
  ethernet: micrel: fix some error codes
  ip_tunnels, bpf: define IP_TUNNEL_OPTS_MAX and use it
  bpf, dst: add and use dst_tclassid helper
  bpf: make skb->tc_classid also readable
  net: mvneta: bm: clarify dependencies
  cls_bpf: reset class and reuse major in da
  ldmvsw: Checkpatch sunvnet.c and sunvnet_common.c
  ldmvsw: Add ldmvsw.c driver code
  ...
2016-03-19 10:05:34 -07:00
Kees Cook
ef95159907 lib: move strtobool() to kstrtobool()
Create the kstrtobool_from_user() helper and move strtobool() logic into
the new kstrtobool() (matching all the other kstrto* functions).
Provides an inline wrapper for existing strtobool() callers.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Joe Perches <joe@perches.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Amitkumar Karwar <akarwar@marvell.com>
Cc: Nishant Sarmukadam <nishants@marvell.com>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: Steve French <sfrench@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Nicolas Dichtel
b5d3755a22 uapi: define DIV_ROUND_UP for userland
DIV_ROUND_UP is defined in linux/kernel.h only for the kernel.
When ethtool.h is included by a userland app, we got the following error:

include/linux/ethtool.h:1218:8: error: variably modified 'queue_mask' at file scope
  __u32 queue_mask[DIV_ROUND_UP(MAX_NUM_QUEUE, 32)];
        ^

Let's add a common definition in uapi and use it everywhere.

Fixes: ac2c7ad0e5 ("net/ethtool: introduce a new ioctl for per queue setting")
CC: Kan Liang <kan.liang@intel.com>
Suggested-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-04 16:10:36 -05:00
Michal Nazarewicz
8f57e4d930 include/linux/kernel.h: change abs() macro so it uses consistent return type
Rewrite abs() so that its return type does not depend on the
architecture and no unexpected type conversion happen inside of it.  The
only conversion is from unsigned to signed type.  char is left as a
return type but treated as a signed type regradless of it's actual
signedness.

With the old version, int arguments were promoted to long and depending
on architecture a long argument might result in s64 or long return type
(which may or may not be the same).

This came after some back and forth with Nicolas.  The current macro has
different return type (for the same input type) depending on
architecture which might be midly iritating.

An alternative version would promote to int like so:

	#define abs(x)	__abs_choose_expr(x, long long,			\
			__abs_choose_expr(x, long,			\
			__builtin_choose_expr(				\
				sizeof(x) <= sizeof(int),		\
				({ int __x = (x); __x<0?-__x:__x; }),	\
				((void)0))))

I have no preference but imagine Linus might.  :] Nicolas argument against
is that promoting to int causes iconsistent behaviour:

	int main(void) {
		unsigned short a = 0, b = 1, c = a - b;
		unsigned short d = abs(a - b);
		unsigned short e = abs(c);
		printf("%u %u\n", d, e);  // prints: 1 65535
	}

Then again, no sane person expects consistent behaviour from C integer
arithmetic.  ;)

Note:

  __builtin_types_compatible_p(unsigned char, char) is always false, and
  __builtin_types_compatible_p(signed char, char) is also always false.

Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-16 11:17:22 -08:00
Hidehiro Kawai
58c5661f21 panic, x86: Allow CPUs to save registers even if looping in NMI context
Currently, kdump_nmi_shootdown_cpus(), a subroutine of crash_kexec(),
sends an NMI IPI to CPUs which haven't called panic() to stop them,
save their register information and do some cleanups for crash dumping.
However, if such a CPU is infinitely looping in NMI context, we fail to
save its register information into the crash dump.

For example, this can happen when unknown NMIs are broadcast to all
CPUs as follows:

  CPU 0                             CPU 1
  ===========================       ==========================
  receive an unknown NMI
  unknown_nmi_error()
    panic()                         receive an unknown NMI
      spin_trylock(&panic_lock)     unknown_nmi_error()
      crash_kexec()                   panic()
                                        spin_trylock(&panic_lock)
                                        panic_smp_self_stop()
                                          infinite loop
        kdump_nmi_shootdown_cpus()
          issue NMI IPI -----------> blocked until IRET
                                          infinite loop...

Here, since CPU 1 is in NMI context, the second NMI from CPU 0 is
blocked until CPU 1 executes IRET. However, CPU 1 never executes IRET,
so the NMI is not handled and the callback function to save registers is
never called.

In practice, this can happen on some servers which broadcast NMIs to all
CPUs when the NMI button is pushed.

To save registers in this case, we need to:

  a) Return from NMI handler instead of looping infinitely
  or
  b) Call the callback function directly from the infinite loop

Inherently, a) is risky because NMI is also used to prevent corrupted
data from being propagated to devices.  So, we chose b).

This patch does the following:

1. Move the infinite looping of CPUs which haven't called panic() in NMI
   context (actually done by panic_smp_self_stop()) outside of panic() to
   enable us to refer pt_regs. Please note that panic_smp_self_stop() is
   still used for normal context.

2. Call a callback of kdump_nmi_shootdown_cpus() directly to save
   registers and do some cleanups after setting waiting_for_crash_ipi which
   is used for counting down the number of CPUs which handled the callback

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Gobinda Charan Maji <gobinda.cemk07@gmail.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Javi Merino <javi.merino@arm.com>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: kexec@lists.infradead.org
Cc: linux-doc@vger.kernel.org
Cc: lkml <linux-kernel@vger.kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Stefan Lippers-Hollmann <s.l-h@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Link: http://lkml.kernel.org/r/20151210014628.25437.75256.stgit@softrs
[ Cleanup comments, fixup formatting. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-12-19 11:07:01 +01:00
Hidehiro Kawai
1717f2096b panic, x86: Fix re-entrance problem due to panic on NMI
If panic on NMI happens just after panic() on the same CPU, panic() is
recursively called. Kernel stalls, as a result, after failing to acquire
panic_lock.

To avoid this problem, don't call panic() in NMI context if we've
already entered panic().

For that, introduce nmi_panic() macro to reduce code duplication. In
the case of panic on NMI, don't return from NMI handlers if another CPU
already panicked.

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Gobinda Charan Maji <gobinda.cemk07@gmail.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Javi Merino <javi.merino@arm.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: kexec@lists.infradead.org
Cc: linux-doc@vger.kernel.org
Cc: lkml <linux-kernel@vger.kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/20151210014626.25437.13302.stgit@softrs
[ Cleanup comments, fixup formatting. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-12-19 11:07:00 +01:00
Andrew Morton
79211c8ed1 remove abs64()
Switch everything to the new and more capable implementation of abs().
Mainly to give the new abs() a bit of a workout.

Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-09 15:11:24 -08:00
Michal Nazarewicz
c8299cb605 kernel.h: make abs() work with 64-bit types
For 64-bit arguments, the abs macro casts it to an int which leads to
lost precision and may cause incorrect results.  To deal with 64-bit
types abs64 macro has been introduced but still there are places where
abs macro is used incorrectly.

To deal with the problem, expand abs macro such that it operates on s64
type when dealing with 64-bit types while still returning long when
dealing with smaller types.

This fixes one known bug (per John):

The internal clocksteering done for fine-grained error correction uses a
: logarithmic approximation, so any time adjtimex() adjusts the clock
: steering, timekeeping_freqadjust() quickly approximates the correct clock
: frequency over a series of ticks.
:
: Unfortunately, the logic in timekeeping_freqadjust(), introduced in commit
: dc491596f6 (Rework frequency adjustments to work better w/ nohz),
: used the abs() function with a s64 error value to calculate the size of
: the approximated adjustment to be made.
:
: Per include/linux/kernel.h: "abs() should not be used for 64-bit types
: (s64, u64, long long) - use abs64()".
:
: Thus on 32-bit platforms, this resulted in the clocksteering to take a
: quite dampended random walk trying to converge on the proper frequency,
: which caused the adjustments to be made much slower then intended (most
: easily observed when large adjustments are made).

Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Reported-by: John Stultz <john.stultz@linaro.org>
Tested-by: John Stultz <john.stultz@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-09 15:11:24 -08:00