Commit Graph

633300 Commits

Author SHA1 Message Date
Linus Torvalds 9d71bdfbcb Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixlet from Ingo Molnar:
 "Remove an unused variable"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  alarmtimer: Remove unused but set variable
2016-10-18 09:57:12 -07:00
Linus Torvalds 2c11fc87ca Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fix from Ingo Molnar:
 "Fix a crash that can trigger when racing with CPU hotplug: we didn't
  use sched-domains data structures carefully enough in select_idle_cpu()"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/fair: Fix sched domains NULL dereference in select_idle_sibling()
2016-10-18 09:53:59 -07:00
Linus Torvalds b75d3886f3 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Four tooling fixes, two kprobes KASAN related fixes and an x86 PMU
  driver fix/cleanup"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf jit: Fix build issue on Ubuntu
  perf jevents: Handle events including .c and .o
  perf/x86/intel: Remove an inconsistent NULL check
  kprobes: Unpoison stack in jprobe_return() for KASAN
  kprobes: Avoid false KASAN reports during stack copy
  perf header: Set nr_numa_nodes only when we parsed all the data
  perf top: Fix refreshing hierarchy entries on TUI
2016-10-18 09:30:18 -07:00
Linus Torvalds e0ed1c22d4 Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Ingo Molnar:
 "Two fixes:

   - a file locks fix (missing critical section, bug introduced in this
     merge window)

   - an x86 down_write() stack frame annotation"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking, fs/locks: Add missing file_sem locks
  locking/rwsem/x86: Add stack frame dependency for ____down_write()
2016-10-18 09:04:17 -07:00
Linus Torvalds 50276c9abb Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Ingo Molnar:
 "Three irqchip driver fixes"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/gicv3: Handle loop timeout proper
  irqchip/jcore: Fix lost per-cpu interrupts
  irqchip/eznps: Acknowledge NPS_IPI before calling the handler
2016-10-18 09:01:22 -07:00
Linus Torvalds 351267d941 Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull misc fixes from Ingo Molnar:
 "A CPU hotplug debuggability fix and three objtool false positive
  warnings fixes for new GCC6 code generation patterns"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  cpu/hotplug: Use distinct name for cpu_hotplug.dep_map
  objtool: Skip all "unreachable instruction" warnings for gcov kernels
  objtool: Improve rare switch jump table pattern detection
  objtool: Support '-mtune=atom' stack frame setup instruction
2016-10-18 08:35:07 -07:00
Linus Torvalds 5aa43efe90 Merge tag 'firewire-update' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394
Pull firewire fixlet from Stefan Richter:
 "IEEE 1394 subsystem patch: catch an initialization error in the packet
  sniffer nosy"

* tag 'firewire-update' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394:
  firewire: nosy: do not ignore errors in ioremap_nocache()
2016-10-18 08:28:08 -07:00
Linus Torvalds 37c1e28931 Merge tag 'drm-fixes-for-v4.9-rc2' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
 "Just had a couple of amdgpu fixes and one core fix I wanted to get out
  early to fix some regressions.

  I'm sure I'll have more stuff this week for -rc2"

* tag 'drm-fixes-for-v4.9-rc2' of git://people.freedesktop.org/~airlied/linux: (22 commits)
  drm: Print device information again in debugfs
  drm/amd/powerplay: fix bug stop dpm can't work on Vi.
  drm/amd/powerplay: notify smu no display by default.
  drm/amdgpu/dpm: implement thermal sensor for CZ/ST
  drm/amdgpu/powerplay: implement thermal sensor for CZ/ST
  drm/amdgpu: disable smu hw first on tear down
  drm/amdgpu: fix amdgpu_need_full_reset (v2)
  drm/amdgpu/si_dpm: Limit clocks on HD86xx part
  drm/amd/powerplay: fix static checker warnings in smu7_hwmgr.c
  drm/amdgpu: potential NULL dereference in debugfs code
  drm/amd/powerplay: fix static checker warnings in smu7_hwmgr.c
  drm/amd/powerplay: fix static checker warnings in iceland_smc.c
  drm/radeon: change vblank_time's calculation method to reduce computational error.
  drm/amdgpu: change vblank_time's calculation method to reduce computational error.
  drm/amdgpu: clarify UVD/VCE special handling for CG
  drm/amd/amdgpu: enable clockgating only after late init
  drm/radeon: allow TA_CS_BC_BASE_ADDR on SI
  drm/amdgpu: initialize the context reset_counter in amdgpu_ctx_init
  drm/amdgpu/gfx8: fix CGCG_CGLS handling
  drm/radeon: fix modeset tear down code
  ...
2016-10-18 08:05:29 -07:00
Peter Zijlstra 5f43086bb9 locking, fs/locks: Add missing file_sem locks
I overlooked a few code-paths that can lead to
locks_delete_global_locks().

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Jeff Layton <jlayton@poochiereds.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Bruce Fields <bfields@fieldses.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-fsdevel@vger.kernel.org
Cc: syzkaller <syzkaller@googlegroups.com>
Link: http://lkml.kernel.org/r/20161008081228.GF3142@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-18 12:21:28 +02:00
Josh Poimboeuf 55a76b59b5 locking/rwsem/x86: Add stack frame dependency for ____down_write()
Arnd reported the following objtool warning:

  kernel/locking/rwsem.o: warning: objtool: down_write_killable()+0x16: call without frame pointer save/setup

The warning means gcc placed the ____down_write() inline asm (and its
call instruction) before the frame pointer setup in
down_write_killable(), which breaks frame pointer convention and can
result in incorrect stack traces.

Force the stack frame to be created before the call instruction by
listing the stack pointer as an output operand in the inline asm
statement.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1188b7015f04baf361e59de499ee2d7272c59dce.1476393828.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-18 12:21:16 +02:00
Junjie Mao 14155cafea btrfs: assign error values to the correct bio structs
Fixes: 4246a0b63b ("block: add a bi_error field to struct bio")
Signed-off-by: Junjie Mao <junjie.mao@enight.me>
Acked-by: David Sterba <dsterba@suse.cz>
Cc: stable@vger.kernel.org # 4.3+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-17 14:16:14 -07:00
Dave Hansen eac0ca77e4 x86, pkeys: remove cruft from never-merged syscalls
pkey_set() and pkey_get() were syscalls present in older versions
of the protection keys patches.  The syscall number definitions
were inadvertently left in place.  This patch removes them.

I did a git grep and verified that these are the last places in
the tree that these appear, save for the protection_keys.c tests
and Documentation.  Those spots talk about functions called
pkey_get/set() which are wrappers for the direct PKRU
instructions, not the syscalls.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: mgorman@techsingularity.net
Cc: arnd@arndb.de
Cc: linux-api@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: luto@kernel.org
Cc: akpm@linux-foundation.org
Fixes: f9afc6197e ("x86: Wire up protection keys system calls")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-17 14:16:13 -07:00
Dave Hansen 71757904ef generic syscalls: kill cruft from removed pkey syscalls
pkey_set() and pkey_get() were syscalls present in older versions
of the protection keys patches.  They were fully excised from the
x86 code, but some cruft was left in the generic syscall code.  The
C++ comments were intended to help to make it more glaring to me to
fix them before actually submitting them.  That technique worked,
but later than I would have liked.

I test-compiled this for arm64.

Fixes: a60f7b69d9 ("generic syscalls: Wire up memory protection keys syscalls")
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
Cc: linux-arch@vger.kernel.org
Cc: mgorman@techsingularity.net
Cc: linux-api@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: luto@kernel.org
Cc: akpm@linux-foundation.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-17 09:50:56 -07:00
Ingo Molnar 0130669966 Merge tag 'perf-urgent-for-mingo-20161017' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent
Pull perf/urgent fixes from Arnaldo Carvalho de Melo:

- Fix handling of NUMA nodes in perf.data files (Jiri Olsa)

- Fix scrolling when refreshing 'perf top --tui --hierarchy' entries (Namhyung Kim)

- Fix building of JIT support on Ubuntu 16.04 (Anton Blanchard)

- Fix handling of events including .c and .o, that were being treated as
  BPF scripts instead of vendor ones (Wang Nan)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-17 16:49:16 +02:00
Anton Blanchard 53613e0054 perf jit: Fix build issue on Ubuntu
When building on Ubuntu 16.04, I get the following error:

Makefile:49: *** the openjdk development package appears to me missing, install and try again.  Stop.

The problem is that update-java-alternatives has multiple spaces between
fields, and cut treats each space as a new delimiter:

java-1.8.0-openjdk-ppc64el     1081       /usr/lib/jvm/java-1.8.0-openjdk-ppc64el

Fix this by using awk, which handles this fine.

Signed-off-by: Anton Blanchard <anton@samba.org>
Reviewed-by: Stephane Eranian <eranian@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1476325243-15788-1-git-send-email-anton@ozlabs.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-10-17 11:25:34 -03:00
Wang Nan 2d470b62fa perf jevents: Handle events including .c and .o
This patch helps with Sukadev's vendor event tree where such events can happen.

>From Andi Kleen:
 Any event including a .c/.o/.bpf currently triggers BPF compilation or loading
 and then an error. This can happen for some Intel vendor events, which cannot
 be used.

This patch fixes this problem by forbidding BPF file patch containing '{', '}'
and ',', make sure flex consumes the leading '{', instead of matching it using
a BPF file path.

Tested result:

  $ perf stat -e '{unc_p_clockticks,unc_p_power_state_occupancy.cores_c0}' -a -I 1000
  invalid or unsupported event: '{unc_p_clockticks,unc_p_power_state_occupancy.cores_c0}'
  Run 'perf list' for a list of valid events
  (as expected, interperted as event)

  $ perf stat -e 'aaa.c' -a -I 1000
  ERROR: problems with path aaa.c: No such file or directory
  (as expected, interpreted as BPF source)

  $ perf stat -e 'aaa.ccc' -a -I 1000
  invalid or unsupported event: 'aaa.ccc'
  (as expected, interpreted as event)

  $ perf stat -e '{aaa.c}' -a -I 1000
  ERROR: problems with path aaa.c: No such file or directory
  event syntax error: '{aaa.c}'
  <SKIP>
  (as expected, interpreted as BPF source)

  $ perf stat -e '{cycles,aaa.c}' -a -I 1000
  ERROR: problems with path aaa.c: No such file or directory
  event syntax error: '{cycles,aaa.c}'
  (as expected, interpreted as BPF source)

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Reported-by: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1475900185-37967-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-10-17 11:24:18 -03:00
Tobias Klauser 54e23845e9 alarmtimer: Remove unused but set variable
Remove the set but unused variable base in alarm_clock_get to fix the
following warning when building with 'W=1':

  kernel/time/alarmtimer.c: In function ‘alarm_timer_create’:
  kernel/time/alarmtimer.c:545:21: warning: variable ‘base’ set but not used [-Wunused-but-set-variable]

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20161017094702.10873-1-tklauser@distanz.ch
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-10-17 11:59:37 +02:00
Daniel Vetter fa860a1751 drm: Print device information again in debugfs
I was a bit over-eager in my cleanup in

commit 95c081c17f
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Tue Jun 21 10:54:12 2016 +0200

    drm: Move master pointer from drm_minor to drm_device

Noticed by Chris Wilson.

Fixes: 95c081c17f ("drm: Move master pointer from drm_minor to drm_device")
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Emil Velikov <emil.l.velikov@gmail.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2016-10-17 16:20:53 +10:00
Dave Airlie bc91657e67 Merge branch 'drm-next-4.9' of git://people.freedesktop.org/~agd5f/linux into drm-next
Fixes for radeon and amdgpu for 4.9:
- allow an additional reg in the SI reg checker
- fix thermal sensor readback on CZ/ST
- misc bug fixes

* 'drm-next-4.9' of git://people.freedesktop.org/~agd5f/linux: (21 commits)
  drm/amd/powerplay: fix bug stop dpm can't work on Vi.
  drm/amd/powerplay: notify smu no display by default.
  drm/amdgpu/dpm: implement thermal sensor for CZ/ST
  drm/amdgpu/powerplay: implement thermal sensor for CZ/ST
  drm/amdgpu: disable smu hw first on tear down
  drm/amdgpu: fix amdgpu_need_full_reset (v2)
  drm/amdgpu/si_dpm: Limit clocks on HD86xx part
  drm/amd/powerplay: fix static checker warnings in smu7_hwmgr.c
  drm/amdgpu: potential NULL dereference in debugfs code
  drm/amd/powerplay: fix static checker warnings in smu7_hwmgr.c
  drm/amd/powerplay: fix static checker warnings in iceland_smc.c
  drm/radeon: change vblank_time's calculation method to reduce computational error.
  drm/amdgpu: change vblank_time's calculation method to reduce computational error.
  drm/amdgpu: clarify UVD/VCE special handling for CG
  drm/amd/amdgpu: enable clockgating only after late init
  drm/radeon: allow TA_CS_BC_BASE_ADDR on SI
  drm/amdgpu: initialize the context reset_counter in amdgpu_ctx_init
  drm/amdgpu/gfx8: fix CGCG_CGLS handling
  drm/radeon: fix modeset tear down code
  drm/radeon: fix up dp aux tear down (v2)
  ...
2016-10-17 09:31:52 +10:00
Dan Carpenter 5c38181ce9 perf/x86/intel: Remove an inconsistent NULL check
Smatch complains that we don't check "event->ctx" consistently.  It's
never NULL so we can just remove the check.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Carrillo-Cisneros <davidcc@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: kernel-janitors@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-16 11:34:14 +02:00
Joonas Lahtinen a705e07b9c cpu/hotplug: Use distinct name for cpu_hotplug.dep_map
Use distinctive name for cpu_hotplug.dep_map to avoid the actual
cpu_hotplug.lock appearing as cpu_hotplug.lock#2 in lockdep splats.

Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Gautham R . Shenoy <ego@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: trivial@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-16 11:09:32 +02:00
Dmitry Vyukov 9f7d416c36 kprobes: Unpoison stack in jprobe_return() for KASAN
I observed false KSAN positives in the sctp code, when
sctp uses jprobe_return() in jsctp_sf_eat_sack().

The stray 0xf4 in shadow memory are stack redzones:

[     ] ==================================================================
[     ] BUG: KASAN: stack-out-of-bounds in memcmp+0xe9/0x150 at addr ffff88005e48f480
[     ] Read of size 1 by task syz-executor/18535
[     ] page:ffffea00017923c0 count:0 mapcount:0 mapping:          (null) index:0x0
[     ] flags: 0x1fffc0000000000()
[     ] page dumped because: kasan: bad access detected
[     ] CPU: 1 PID: 18535 Comm: syz-executor Not tainted 4.8.0+ #28
[     ] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[     ]  ffff88005e48f2d0 ffffffff82d2b849 ffffffff0bc91e90 fffffbfff10971e8
[     ]  ffffed000bc91e90 ffffed000bc91e90 0000000000000001 0000000000000000
[     ]  ffff88005e48f480 ffff88005e48f350 ffffffff817d3169 ffff88005e48f370
[     ] Call Trace:
[     ]  [<ffffffff82d2b849>] dump_stack+0x12e/0x185
[     ]  [<ffffffff817d3169>] kasan_report+0x489/0x4b0
[     ]  [<ffffffff817d31a9>] __asan_report_load1_noabort+0x19/0x20
[     ]  [<ffffffff82d49529>] memcmp+0xe9/0x150
[     ]  [<ffffffff82df7486>] depot_save_stack+0x176/0x5c0
[     ]  [<ffffffff817d2031>] save_stack+0xb1/0xd0
[     ]  [<ffffffff817d27f2>] kasan_slab_free+0x72/0xc0
[     ]  [<ffffffff817d05b8>] kfree+0xc8/0x2a0
[     ]  [<ffffffff85b03f19>] skb_free_head+0x79/0xb0
[     ]  [<ffffffff85b0900a>] skb_release_data+0x37a/0x420
[     ]  [<ffffffff85b090ff>] skb_release_all+0x4f/0x60
[     ]  [<ffffffff85b11348>] consume_skb+0x138/0x370
[     ]  [<ffffffff8676ad7b>] sctp_chunk_put+0xcb/0x180
[     ]  [<ffffffff8676ae88>] sctp_chunk_free+0x58/0x70
[     ]  [<ffffffff8677fa5f>] sctp_inq_pop+0x68f/0xef0
[     ]  [<ffffffff8675ee36>] sctp_assoc_bh_rcv+0xd6/0x4b0
[     ]  [<ffffffff8677f2c1>] sctp_inq_push+0x131/0x190
[     ]  [<ffffffff867bad69>] sctp_backlog_rcv+0xe9/0xa20
[ ... ]
[     ] Memory state around the buggy address:
[     ]  ffff88005e48f380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[     ]  ffff88005e48f400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[     ] >ffff88005e48f480: f4 f4 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[     ]                    ^
[     ]  ffff88005e48f500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[     ]  ffff88005e48f580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[     ] ==================================================================

KASAN stack instrumentation poisons stack redzones on function entry
and unpoisons them on function exit. If a function exits abnormally
(e.g. with a longjmp like jprobe_return()), stack redzones are left
poisoned. Later this leads to random KASAN false reports.

Unpoison stack redzones in the frames we are going to jump over
before doing actual longjmp in jprobe_return().

Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: kasan-dev@googlegroups.com
Cc: surovegin@google.com
Cc: rostedt@goodmis.org
Link: http://lkml.kernel.org/r/1476454043-101898-1-git-send-email-dvyukov@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-16 11:02:31 +02:00
Dmitry Vyukov 9254139ad0 kprobes: Avoid false KASAN reports during stack copy
Kprobes save and restore raw stack chunks with memcpy().
With KASAN these chunks can contain poisoned stack redzones,
as the result memcpy() interceptor produces false
stack out-of-bounds reports.

Use __memcpy() instead of memcpy() for stack copying.
__memcpy() is not instrumented by KASAN and does not lead
to the false reports.

Currently there is a spew of KASAN reports during boot
if CONFIG_KPROBES_SANITY_TEST is enabled:

[   ] Kprobe smoke test: started
[   ] ==================================================================
[   ] BUG: KASAN: stack-out-of-bounds in setjmp_pre_handler+0x17c/0x280 at addr ffff88085259fba8
[   ] Read of size 64 by task swapper/0/1
[   ] page:ffffea00214967c0 count:0 mapcount:0 mapping:          (null) index:0x0
[   ] flags: 0x2fffff80000000()
[   ] page dumped because: kasan: bad access detected
[...]

Reported-by: CAI Qian <caiqian@redhat.com>
Tested-by: CAI Qian <caiqian@redhat.com>
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kasan-dev@googlegroups.com
[ Improved various details. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-16 10:58:59 +02:00
Josh Poimboeuf 9cfffb1168 objtool: Skip all "unreachable instruction" warnings for gcov kernels
Recently objtool has started reporting a few "unreachable instruction"
warnings when CONFIG_GCOV is enabled for newer versions of GCC.  Usually
this warning means there's some new control flow that objtool doesn't
understand.  But in this case, objtool is correct and the instructions
really are inaccessible.  It's an annoying quirk of gcov, but it's
harmless, so it's ok to just silence the warnings.

With older versions of GCC, it was relatively easy to detect
gcov-specific instructions and to skip any unreachable warnings produced
by them.  But GCC 6 has gotten craftier.

Instead of continuing to play whack-a-mole with gcov, just use a bigger,
more permanent hammer and disable unreachable warnings for the whole
file when gcov is enabled.  This is fine to do because a) unreachable
warnings are usually of questionable value; and b) gcov isn't used for
production kernels and we can relax the checks a bit there.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.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>
Link: http://lkml.kernel.org/r/38d5c87d61d9cd46486dd2c86f46603dff0df86f.1476393584.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-16 09:12:36 +02:00
Josh Poimboeuf 3732710ff6 objtool: Improve rare switch jump table pattern detection
GCC 6 added a new switch statement jump table optimization which makes
objtool's life harder.  It looks like:

  mov [rodata addr],%reg1
  ... some instructions ...
  jmpq *(%reg1,%reg2,8)

The optimization is quite rare, but objtool still needs to be able to
identify the pattern so that it can follow all possible control flow
paths related to the switch statement.

In order to detect the pattern, objtool starts from the indirect jump
and scans backwards through the function until it finds the first
instruction in the pattern.  If it encounters an unconditional jump
along the way, it stops and considers the pattern to be not found.

As it turns out, unconditional jumps can happen, as long as they are
small forward jumps within the range being scanned.

This fixes the following warnings:

  drivers/infiniband/sw/rxe/rxe_comp.o: warning: objtool: rxe_completer()+0x2f4: sibling call from callable instruction with changed frame pointer
  drivers/infiniband/sw/rxe/rxe_resp.o: warning: objtool: rxe_responder()+0x10f: sibling call from callable instruction with changed frame pointer

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.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>
Link: http://lkml.kernel.org/r/8a9ed68ae1780e8d3963e4ee13f2f257fe3a3c33.1476393584.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-16 09:12:35 +02:00