Commit Graph

617396 Commits

Author SHA1 Message Date
Arnaldo Carvalho de Melo
fd2275984d perf probe: Do not use map_load filters for function
It is simpler to just do the loop, no need for globals and the last user
of such facility disappears.

Testing:

  # perf probe -F [a-z]*recvmsg
  aead_recvmsg
  compat_SyS_recvmsg
  compat_sys_recvmsg
  hash_recvmsg
  inet_recvmsg
  kernel_recvmsg
  netlink_recvmsg
  packet_recvmsg
  ping_recvmsg
  raw_recvmsg
  rawv6_recvmsg
  rng_recvmsg
  security_socket_recvmsg
  selinux_socket_recvmsg
  skcipher_recvmsg
  sock_common_recvmsg
  sock_no_recvmsg
  sock_recvmsg
  sys_recvmsg
  tcp_recvmsg
  udp_recvmsg
  udpv6_recvmsg
  unix_dgram_recvmsg
  unix_seqpacket_recvmsg
  unix_stream_recvmsg
  #

Without filters:

  # perf probe -F | tail -5
  zswap_pool_create
  zswap_pool_current
  zswap_update_total_size
  zswap_writeback_entry
  zswap_zpool_param_set
  #
  # perf probe -F | wc -l
  33311
  #

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20160831130427.GA13095@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-09-01 09:43:57 -03:00
Miklos Szeredi
026e5e0cc1 ovl: update doc
Some of the documented quirks no longer apply.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:12:00 +02:00
Miklos Szeredi
7cb35119d0 ovl: listxattr: use strnlen()
Be defensive about what underlying fs provides us in the returned xattr
list buffer.  If it's not properly null terminated, bail out with a warning
insead of BUG.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: <stable@vger.kernel.org>
2016-09-01 11:12:00 +02:00
Andreas Gruenbacher
0eb45fc3bb ovl: Switch to generic_getxattr
Now that overlayfs has xattr handlers for iop->{set,remove}xattr, use
those same handlers for iop->getxattr as well.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:12:00 +02:00
Miklos Szeredi
ce31513a91 ovl: copyattr after setting POSIX ACL
Setting POSIX acl may also modify the file mode, so need to copy that up to
the overlay inode.

Reported-by: Eryu Guan <eguan@redhat.com>
Fixes: d837a49bd5 ("ovl: fix POSIX ACL setting")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:12:00 +02:00
Andreas Gruenbacher
0e585ccc13 ovl: Switch to generic_removexattr
Commit d837a49bd5 ("ovl: fix POSIX ACL setting") switches from
iop->setxattr from ovl_setxattr to generic_setxattr, so switch from
ovl_removexattr to generic_removexattr as well.  As far as permission
checking goes, the same rules should apply in either case.

While doing that, rename ovl_setxattr to ovl_xattr_set to indicate that
this is not an iop->setxattr implementation and remove the unused inode
argument.

Move ovl_other_xattr_set above ovl_own_xattr_set so that they match the
order of handlers in ovl_xattr_handlers.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Fixes: d837a49bd5 ("ovl: fix POSIX ACL setting")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:12:00 +02:00
Andreas Gruenbacher
0c97be22f9 ovl: Get rid of ovl_xattr_noacl_handlers array
Use an ordinary #ifdef to conditionally include the POSIX ACL handlers
in ovl_xattr_handlers, like the other filesystems do.  Flag the code
that is now only used conditionally with __maybe_unused.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:11:59 +02:00
Andreas Gruenbacher
fe2b759523 ovl: Fix OVL_XATTR_PREFIX
Make sure ovl_own_xattr_handler only matches attribute names starting
with "overlay.", not "overlayXXX".

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Fixes: d837a49bd5 ("ovl: fix POSIX ACL setting")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:11:59 +02:00
Colin Ian King
fd36570a88 ovl: fix spelling mistake: "directries" -> "directories"
Trivial fix to spelling mistake in pr_err message.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:11:59 +02:00
Miklos Szeredi
2a3a2a3f35 ovl: don't cache acl on overlay layer
Some operations (setxattr/chmod) can make the cached acl stale.  We either
need to clear overlay's acl cache for the affected inode or prevent acl
caching on the overlay altogether.  Preventing caching has the following
advantages:

 - no double caching, less memory used

 - overlay cache doesn't go stale when fs clears it's own cache

Possible disadvantage is performance loss.  If that becomes a problem
get_acl() can be optimized for overlayfs.

This patch disables caching by pre setting i_*acl to a value that

  - has bit 0 set, so is_uncached_acl() will return true

  - is not equal to ACL_NOT_CACHED, so get_acl() will not overwrite it

The constant -3 was chosen for this purpose.

Fixes: 39a25b2b37 ("ovl: define ->get_acl() for overlay inodes")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:11:59 +02:00
Miklos Szeredi
5201dc449e ovl: use cached acl on underlying layer
Instead of calling ->get_acl() directly, use get_acl() to get the cached
value.

We will have the acl cached on the underlying inode anyway, because we do
permission checking on the both the overlay and the underlying fs.

So, since we already have double caching, this improves performance without
any cost.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:11:59 +02:00
Miklos Szeredi
eea2fb4851 ovl: proper cleanup of workdir
When mounting overlayfs it needs a clean "work" directory under the
supplied workdir.

Previously the mount code removed this directory if it already existed and
created a new one.  If the removal failed (e.g. directory was not empty)
then it fell back to a read-only mount not using the workdir.

While this has never been reported, it is possible to get a non-empty
"work" dir from a previous mount of overlayfs in case of crash in the
middle of an operation using the work directory.

In this case the left over state should be discarded and the overlay
filesystem will be consistent, guaranteed by the atomicity of operations on
moving to/from the workdir to the upper layer.

This patch implements cleaning out any files left in workdir.  It is
implemented using real recursion for simplicity, but the depth is limited
to 2, because the worst case is that of a directory containing whiteouts
under "work".

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: <stable@vger.kernel.org>
2016-09-01 11:11:59 +02:00
Miklos Szeredi
c11b9fdd6a ovl: remove posix_acl_default from workdir
Clear out posix acl xattrs on workdir and also reset the mode after
creation so that an inherited sgid bit is cleared.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: <stable@vger.kernel.org>
2016-09-01 11:11:59 +02:00
Miklos Szeredi
38b256973e ovl: handle umask and posix_acl_default correctly on creation
Setting MS_POSIXACL in sb->s_flags has the side effect of passing mode to
create functions without masking against umask.

Another problem when creating over a whiteout is that the default posix acl
is not inherited from the parent dir (because the real parent dir at the
time of creation is the work directory).

Fix these problems by:

 a) If upper fs does not have MS_POSIXACL, then mask mode with umask.

 b) If creating over a whiteout, call posix_acl_create() to get the
 inherited acls.  After creation (but before moving to the final
 destination) set these acls on the created file.  posix_acl_create() also
 updates the file creation mode as appropriate.

Fixes: 39a25b2b37 ("ovl: define ->get_acl() for overlay inodes")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:11:59 +02:00
Dave Airlie
27dd73503f Merge branch 'msm-fixes-4.8' of git://people.freedesktop.org/~robclark/linux into drm-fixes
copy from user fixes.

* 'msm-fixes-4.8' of git://people.freedesktop.org/~robclark/linux:
  drm/msm: protect against faults from copy_from_user() in submit ioctl
  drm/msm: fix use of copy_from_user() while holding spinlock
2016-09-01 06:34:09 +10:00
Mateusz Guzik
5efc244346 audit: fix exe_file access in audit_exe_compare
Prior to the change the function would blindly deference mm, exe_file
and exe_file->f_inode, each of which could have been NULL or freed.

Use get_task_exe_file to safely obtain stable exe_file.

Signed-off-by: Mateusz Guzik <mguzik@redhat.com>
Acked-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Richard Guy Briggs <rgb@redhat.com>
Cc: <stable@vger.kernel.org> # 4.3.x
Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-08-31 16:16:35 -04:00
Mateusz Guzik
cd81a9170e mm: introduce get_task_exe_file
For more convenient access if one has a pointer to the task.

As a minor nit take advantage of the fact that only task lock + rcu are
needed to safely grab ->exe_file. This saves mm refcount dance.

Use the helper in proc_exe_link.

Signed-off-by: Mateusz Guzik <mguzik@redhat.com>
Acked-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Richard Guy Briggs <rgb@redhat.com>
Cc: <stable@vger.kernel.org> # 4.3.x
Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-08-31 16:11:20 -04:00
Dave Airlie
8509eb1961 Merge branch 'drm-fixes-4.8' of git://people.freedesktop.org/~agd5f/linux into drm-fixes
Fixes for 4.8:
- 2 CI S4 fixes
- error handling fix

* 'drm-fixes-4.8' of git://people.freedesktop.org/~agd5f/linux:
  drm/amdgpu: record error code when ring test failed
  drm/amd/amdgpu: compute ring test fail during S4 on CI
  drm/amd/amdgpu: sdma resume fail during S4 on CI
2016-09-01 06:03:35 +10:00
Chunming Zhou
1f703e6679 drm/amdgpu: record error code when ring test failed
Otherwise we may miss errors.

Signed-off-by: Chunming Zhou <David1.Zhou@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
2016-08-31 12:45:56 -04:00
jimqu
53960b4f89 drm/amd/amdgpu: compute ring test fail during S4 on CI
unhalt Instrction Fetch Unit after all rings are inited.

Signed-off-by: JimQu <Jim.Qu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
2016-08-31 12:45:17 -04:00
jimqu
10ea943406 drm/amd/amdgpu: sdma resume fail during S4 on CI
SDMA could be fail in the thaw() and restore() processes, do software reset
if each SDMA engine is busy.

Signed-off-by: JimQu <Jim.Qu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
2016-08-31 12:44:45 -04:00
Linus Torvalds
071e31e254 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto fixes from Herbert Xu:
 "This fixes the following issues:

   - Kconfig problem that prevented mxc-rnga from being enabled

   - bogus key sizes in qat aes-xts

   - buggy aes-xts code in vmx"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: vmx - fix null dereference in p8_aes_xts_crypt
  crypto: qat - fix aes-xts key sizes
  hwrng: mxc-rnga - Fix Kconfig dependency
2016-08-31 09:42:14 -07:00
Linus Torvalds
9f834ec18d binfmt_elf: switch to new creds when switching to new mm
We used to delay switching to the new credentials until after we had
mapped the executable (and possible elf interpreter).  That was kind of
odd to begin with, since the new executable will actually then _run_
with the new creds, but whatever.

The bigger problem was that we also want to make sure that we turn off
prof events and tracing before we start mapping the new executable
state.  So while this is a cleanup, it's also a fix for a possible
information leak.

Reported-by: Robert Święcki <robert@swiecki.net>
Tested-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-31 09:13:56 -07:00
Jimi Damon
c8d192428f serial: 8250: added acces i/o products quad and octal serial cards
Added devices ids for acces i/o products quad and octal serial cards
that make use of existing Pericom PI7C9X7954 and PI7C9X7958
configurations .

Signed-off-by: Jimi Damon <jdamon@accesio.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 16:28:26 +02:00
Andy Shevchenko
47b34d2ef2 serial: 8250_mid: fix divide error bug if baud rate is 0
Since the commit c1a67b48f6 ("serial: 8250_pci: replace switch-case by
formula for Intel MID"), the 8250 driver crashes in the byt_set_termios()
function with a divide error. This is caused by the fact that a baud rate of 0
(B0) is not handled properly. Fix it by falling back to B9600 in this case.

Reported-by: "Mendez Salinas, Fernando" <fernando.mendez.salinas@intel.com>
Fixes: c1a67b48f6 ("serial: 8250_pci: replace switch-case by formula for Intel MID")
Cc: stable@vger.kernel.org
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 15:49:26 +02:00
Andy Shevchenko
5db4f7f80d Revert "tty/serial/8250: use mctrl_gpio helpers"
Serial console is broken in v4.8-rcX. Mika and I independently bisected down to
commit 4ef03d3287 ("tty/serial/8250: use mctrl_gpio helpers").

Since neither author nor anyone else didn't propose a solution we better revert
it for now.

This reverts commit 4ef03d3287.

Link: https://lkml.kernel.org/r/20160809130229.GN1729@lahna.fi.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 15:36:01 +02:00
Konstantin Khlebnikov
17d0774f80 sysfs: correctly handle read offset on PREALLOC attrs
Attributes declared with __ATTR_PREALLOC use sysfs_kf_read() which returns
zero bytes for non-zero offset. This breaks script checkarray in mdadm tool
in debian where /bin/sh is 'dash' because its builtin 'read' reads only one
byte at a time. Script gets 'i' instead of 'idle' when reads current action
from /sys/block/$dev/md/sync_action and as a result does nothing.

This patch adds trivial implementation of partial read: generate whole
string and move required part into buffer head.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Fixes: 4ef67a8c95 ("sysfs/kernfs: make read requests on pre-alloc files use the buffer.")
Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=787950
Cc: Stable <stable@vger.kernel.org> # v3.19+
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 15:14:44 +02:00
Martin Fuzzey
96b0af4b72 documentation: drivers/core/of: fix name of of_node symlink
commit 5590f3196b ("drivers/core/of: Add symlink to device-tree from
devices with an OF node") added a symlink called "of_node" to sysfs
however the documentation describes it as "of_path".

Fix the documentation to match what the code actually does.

Signed-off-by: Martin Fuzzey <mfuzzey@parkeon.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 15:14:44 +02:00
Tejun Heo
df6a58c5c5 kernfs: don't depend on d_find_any_alias() when generating notifications
kernfs_notify_workfn() sends out file modified events for the
scheduled kernfs_nodes.  Because the modifications aren't from
userland, it doesn't have the matching file struct at hand and can't
use fsnotify_modify().  Instead, it looked up the inode and then used
d_find_any_alias() to find the dentry and used fsnotify_parent() and
fsnotify() directly to generate notifications.

The assumption was that the relevant dentries would have been pinned
if there are listeners, which isn't true as inotify doesn't pin
dentries at all and watching the parent doesn't pin the child dentries
even for dnotify.  This led to, for example, inotify watchers not
getting notifications if the system is under memory pressure and the
matching dentries got reclaimed.  It can also be triggered through
/proc/sys/vm/drop_caches or a remount attempt which involves shrinking
dcache.

fsnotify_parent() only uses the dentry to access the parent inode,
which kernfs can do easily.  Update kernfs_notify_workfn() so that it
uses fsnotify() directly for both the parent and target inodes without
going through d_find_any_alias().  While at it, supply the target file
name to fsnotify() from kernfs_node->name.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Evgeny Vereshchagin <evvers@ya.ru>
Fixes: d911d98748 ("kernfs: make kernfs_notify() trigger inotify events too")
Cc: John McCutchan <john@johnmccutchan.com>
Cc: Robert Love <rlove@rlove.org>
Cc: Eric Paris <eparis@parisplace.org>
Cc: stable@vger.kernel.org # v3.16+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 14:48:52 +02:00
Lukas Wunner
ccdf3b888d thunderbolt: Don't declare Falcon Ridge unsupported
Falcon Ridge 4C has been supported by the driver from the beginning,
Falcon Ridge 2C support was just added. Don't irritate users with a
warning declaring the opposite.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 13:25:02 +02:00
Xavier Gnata
82a6a81c2a thunderbolt: Add support for INTEL_FALCON_RIDGE_2C controller.
From: Xavier Gnata <xavier.gnata@gmail.com>

Add support to INTEL_FALCON_RIDGE_2C controller and corresponding quirk
to support suspend/resume.
Tested against 4.7 master on a MacBook Air 11" 2015.

Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 13:25:02 +02:00
Andreas Noever
25eb7e5c74 thunderbolt: Fix resume quirk for Falcon Ridge 4C.
The quirk 'quirk_apple_wait_for_thunderbolt' did not fire on Falcon
Ridge 4C controllers with subdevice/subvendor set to zero. This lead
to lost pci devices on system resume.

Older thunderbolt controllers (pre Falcon Ridge) used the same device id
for bridges and for the controller. On Apple hardware the subvendor- &
subdevice-ids were set for the controller, but not for bridges. So that
is what was used to differentiate between the two. Starting with Falcon
Ridge bridges and controllers received different device ids.
Additionally on some MacBookPro models (but not all) the
subvendor/subdevice was zeroed.

Starting with a42fb351c (thunderbolt: Allow loading of module on recent
Apple MacBooks with thunderbolt 2 controller) the thunderbolt driver
binds to all Falcon Ridge 4C controllers (irregardless of
subvendor/subdevice). The corresponding quirk was not updated.

This commit changes the quirk to check the device class instead of its
subvendor-/subdeviceids. This works for all generations of Thunderbolt
controllers.

Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 13:25:02 +02:00
Michael Ellerman
c012268b37 lkdtm: Mark lkdtm_rodata_do_nothing() notrace
lkdtm_rodata_do_nothing() is an empty function which is generated in
order to test the non-executability of rodata.

Currently if function tracing is enabled then an mcount callsite will be
generated for lkdtm_rodata_do_nothing(), and it will appear in the list
of available functions for function tracing (available_filter_functions).

Given it's purpose purely as a test function, it seems preferable for
lkdtm_rodata_do_nothing() to be marked notrace, so it doesn't appear as
traceable.

This also avoids triggering a linker bug on powerpc:

  https://sourceware.org/bugzilla/show_bug.cgi?id=20428

When the linker sees code that needs to generate a call stub, eg. a
branch to mcount(), it assumes the section is executable and
dereferences a NULL pointer leading to a linker segfault. Marking
lkdtm_rodata_do_nothing() notrace avoids triggering the bug because the
function contains no other function calls.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 13:12:38 +02:00
Peter Wu
279cf3f238 drm/nouveau/acpi: use DSM if bridge does not support D3cold
Even if PR3 support is available on the bridge, it will not be used if
the PCI layer considers it unavailable (i.e. on all laptops from 2013
and 2014). Ensure that this condition is checked to allow a fallback to
the Optimus DSM for device poweroff.

Initially I wanted to call pci_d3cold_enable before checking bridge_d3
(in case the user changed d3cold_allowed), but that is such an unlikely
case and likely fragile anyway. The current patch is suggested by Mika
in http://www.spinics.net/lists/linux-pci/msg52599.html

Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Peter Wu <peter@lekensteyn.nl>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2016-08-31 16:54:05 +10:00
Paul E. McKenney
d7737ce964 PM / runtime: Add _rcuidle suffix to allow rpm_idle() use from idle
This commit appends a few _rcuidle suffixes to fix the following
RCU-used-from-idle bug:

> ===============================
> [ INFO: suspicious RCU usage. ]
> 4.6.0-rc5-next-20160426+ #1116 Not tainted
> -------------------------------
> include/trace/events/rpm.h:95 suspicious rcu_dereference_check() usage!
>
> other info that might help us debug this:
>
>
> RCU used illegally from idle CPU!
> rcu_scheduler_active = 1, debug_locks = 0
> RCU used illegally from extended quiescent state!
> 1 lock held by swapper/0/0:
>  #0:  (&(&dev->power.lock)->rlock){-.-...}, at: [<c052cc2c>] __rpm_callback+0x58/0x60
>
> stack backtrace:
> CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1116
> Hardware name: Generic OMAP36xx (Flattened Device Tree)
> [<c0110290>] (unwind_backtrace) from [<c010c3a8>] (show_stack+0x10/0x14)
> [<c010c3a8>] (show_stack) from [<c047fd68>] (dump_stack+0xb0/0xe4)
> [<c047fd68>] (dump_stack) from [<c052d5d0>] (rpm_suspend+0x580/0x768)
> [<c052d5d0>] (rpm_suspend) from [<c052ec58>] (__pm_runtime_suspend+0x64/0x84)
> [<c052ec58>] (__pm_runtime_suspend) from [<c04bf25c>] (omap2_gpio_prepare_for_idle+0x5c/0x70)
> [<c04bf25c>] (omap2_gpio_prepare_for_idle) from [<c0125568>] (omap_sram_idle+0x140/0x244)
> [<c0125568>] (omap_sram_idle) from [<c01269dc>] (omap3_enter_idle_bm+0xfc/0x1ec)
> [<c01269dc>] (omap3_enter_idle_bm) from [<c0601bdc>] (cpuidle_enter_state+0x80/0x3d4)
> [<c0601bdc>] (cpuidle_enter_state) from [<c0183b08>] (cpu_startup_entry+0x198/0x3a0)
> [<c0183b08>] (cpu_startup_entry) from [<c0b00c0c>] (start_kernel+0x354/0x3c8)
> [<c0b00c0c>] (start_kernel) from [<8000807c>] (0x8000807c)

In the immortal words of Steven Rostedt, "*Whack* *Whack* *Whack*!!!"

Reported-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
WhACKED-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-31 03:00:59 +02:00
Paul E. McKenney
d44c950e93 PM / runtime: Add _rcuidle suffix to allow rpm_resume() to be called from idle
This commit applies another _rcuidle suffix to fix an RCU use from
idle.

> ===============================
> [ INFO: suspicious RCU usage. ]
> 4.6.0-rc5-next-20160426+ #1122 Not tainted
> -------------------------------
> include/trace/events/rpm.h:69 suspicious rcu_dereference_check() usage!
>
> other info that might help us debug this:
>
>
> RCU used illegally from idle CPU!
> rcu_scheduler_active = 1, debug_locks = 0
> RCU used illegally from extended quiescent state!
> 1 lock held by swapper/0/0:
>  #0:  (&(&dev->power.lock)->rlock){-.-...}, at: [<c052e3dc>] __pm_runtime_resume+0x3c/0x64
>
> stack backtrace:
> CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1122
> Hardware name: Generic OMAP36xx (Flattened Device Tree)
> [<c0110290>] (unwind_backtrace) from [<c010c3a8>] (show_stack+0x10/0x14)
> [<c010c3a8>] (show_stack) from [<c047fd68>] (dump_stack+0xb0/0xe4)
> [<c047fd68>] (dump_stack) from [<c052e178>] (rpm_resume+0x5cc/0x7f4)
> [<c052e178>] (rpm_resume) from [<c052e3ec>] (__pm_runtime_resume+0x4c/0x64)
> [<c052e3ec>] (__pm_runtime_resume) from [<c04bf2c4>] (omap2_gpio_resume_after_idle+0x54/0x68)
> [<c04bf2c4>] (omap2_gpio_resume_after_idle) from [<c01269dc>] (omap3_enter_idle_bm+0xfc/0x1ec)
> [<c01269dc>] (omap3_enter_idle_bm) from [<c060198c>] (cpuidle_enter_state+0x80/0x3d4)
> [<c060198c>] (cpuidle_enter_state) from [<c0183b08>] (cpu_startup_entry+0x198/0x3a0)
> [<c0183b08>] (cpu_startup_entry) from [<c0b00c0c>] (start_kernel+0x354/0x3c8)
> [<c0b00c0c>] (start_kernel) from [<8000807c>] (0x8000807c)

Reported-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-31 02:59:20 +02:00
Wei Yongjun
bd37e022e3 cpufreq: dt: Add terminate entry for of_device_id tables
Make sure of_device_id tables are NULL terminated.

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Fixes: f56aad1d98 (cpufreq: dt: Add generic platform-device creation support)
CC: 4.7+ <stable@vger.kernel.org> # 4.7+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-31 02:49:05 +02:00
Bhaktipriya Shridhar
edd1ea2a8a dm bufio: remove use of deprecated create_singlethread_workqueue()
The workqueue "dm_bufio_wq" queues a single work item &dm_bufio_work so
it doesn't require execution ordering.  Hence, alloc_workqueue() has
been used to replace the deprecated create_singlethread_workqueue().

The WQ_MEM_RECLAIM flag has been set since DM requires forward progress
under memory pressure.

Since there are fixed number of work items, explicit concurrency
limit is unnecessary here.

Signed-off-by: Bhaktipriya Shridhar <bhaktipriya96@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2016-08-30 19:45:20 -04:00
Eric Biggers
5d0be84ec0 dm crypt: fix free of bad values after tfm allocation failure
If crypt_alloc_tfms() had to allocate multiple tfms and it failed before
the last allocation, then it would call crypt_free_tfms() and could free
pointers from uninitialized memory -- due to the crypt_free_tfms() check
for non-zero cc->tfms[i].  Fix by allocating zeroed memory.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
2016-08-30 19:45:19 -04:00
Mikulas Patocka
4e870e948f dm crypt: fix error with too large bios
When dm-crypt processes writes, it allocates a new bio in
crypt_alloc_buffer().  The bio is allocated from a bio set and it can
have at most BIO_MAX_PAGES vector entries, however the incoming bio can be
larger (e.g. if it was allocated by bcache).  If the incoming bio is
larger, bio_alloc_bioset() fails and an error is returned.

To avoid the error, we test for a too large bio in the function
crypt_map() and use dm_accept_partial_bio() to split the bio.
dm_accept_partial_bio() trims the current bio to the desired size and
asks DM core to send another bio with the rest of the data.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org # v3.16+
2016-08-30 19:44:11 -04:00
Vladimir Zapolskiy
91e630d9ae dm log writes: fix check of kthread_run() return value
The kthread_run() function returns either a valid task_struct or
ERR_PTR() value, check for NULL is invalid.  This change fixes potential
for oops, e.g. in OOM situation.

Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
2016-08-30 19:41:43 -04:00
Linus Torvalds
61b5ebd6ff Fix fatal signal delivery after ptrace reordering.
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Merge tag 'seccomp-v4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull seccomp fix from Kees Cook:
 "Fix fatal signal delivery after ptrace reordering"

* tag 'seccomp-v4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  seccomp: Fix tracer exit notifications during fatal signals
2016-08-30 16:25:57 -07:00
Kees Cook
485a252a55 seccomp: Fix tracer exit notifications during fatal signals
This fixes a ptrace vs fatal pending signals bug as manifested in
seccomp now that seccomp was reordered to happen after ptrace. The
short version is that seccomp should not attempt to call do_exit()
while fatal signals are pending under a tracer. The existing code was
trying to be as defensively paranoid as possible, but it now ends up
confusing ptrace. Instead, the syscall can just be skipped (which solves
the original concern that the do_exit() was addressing) and normal signal
handling, tracer notification, and process death can happen.

Paraphrasing from the original bug report:

If a tracee task is in a PTRACE_EVENT_SECCOMP trap, or has been resumed
after such a trap but not yet been scheduled, and another task in the
thread-group calls exit_group(), then the tracee task exits without the
ptracer receiving a PTRACE_EVENT_EXIT notification. Test case here:
https://gist.github.com/khuey/3c43ac247c72cef8c956ca73281c9be7

The bug happens because when __seccomp_filter() detects
fatal_signal_pending(), it calls do_exit() without dequeuing the fatal
signal. When do_exit() sends the PTRACE_EVENT_EXIT notification and
that task is descheduled, __schedule() notices that there is a fatal
signal pending and changes its state from TASK_TRACED to TASK_RUNNING.
That prevents the ptracer's waitpid() from returning the ptrace event.
A more detailed analysis is here:
https://github.com/mozilla/rr/issues/1762#issuecomment-237396255.

Reported-by: Robert O'Callahan <robert@ocallahan.org>
Reported-by: Kyle Huey <khuey@kylehuey.com>
Tested-by: Kyle Huey <khuey@kylehuey.com>
Fixes: 93e35efb8d ("x86/ptrace: run seccomp after ptrace")
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: James Morris <james.l.morris@oracle.com>
2016-08-30 16:12:46 -07:00
Mikulas Patocka
7efb367320 dm log writes: fix bug with too large bios
bio_alloc() can allocate a bio with at most BIO_MAX_PAGES (256) vector
entries.  However, the incoming bio may have more vector entries if it
was allocated by other means.  For example, bcache submits bios with
more than BIO_MAX_PAGES entries.  This results in bio_alloc() failure.

To avoid the failure, change the code so that it allocates bio with at
most BIO_MAX_PAGES entries.  If the incoming bio has more entries,
bio_add_page() will fail and a new bio will be allocated - the code that
handles bio_add_page() failure already exists in the dm-log-writes
target.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reviewed-by: Josef Bacik <jbacik@fb,com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org # v4.1+
2016-08-30 16:20:55 -04:00
Mikulas Patocka
a5d60783df dm log writes: move IO accounting earlier to fix error path
Move log_one_block()'s atomic_inc(&lc->io_blocks) before bio_alloc() to
fix a bug that the target hangs if bio_alloc() fails.  The error path
does put_io_block(lc), so atomic_inc(&lc->io_blocks) must occur before
invoking the error path to avoid underflow of lc->io_blocks.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reviewed-by: Josef Bacik <jbacik@fb,com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
2016-08-30 16:16:49 -04:00
Linus Torvalds
86a1679860 Merge tag 'md/4.8-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md
Pull MD fixes from Shaohua Li:
 "This includes several bug fixes:

   - Alexey Obitotskiy fixed a hang for faulty raid5 array with external
     management

   - Song Liu fixed two raid5 journal related bugs

   - Tomasz Majchrzak fixed a bad block recording issue and an
     accounting issue for raid10

   - ZhengYuan Liu fixed an accounting issue for raid5

   - I fixed a potential race condition and memory leak with DIF/DIX
     enabled

   - other trival fixes"

* tag 'md/4.8-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
  raid5: avoid unnecessary bio data set
  raid5: fix memory leak of bio integrity data
  raid10: record correct address of bad block
  md-cluster: fix error return code in join()
  r5cache: set MD_JOURNAL_CLEAN correctly
  md: don't print the same repeated messages about delayed sync operation
  md: remove obsolete ret in md_start_sync
  md: do not count journal as spare in GET_ARRAY_INFO
  md: Prevent IO hold during accessing to faulty raid5 array
  MD: hold mddev lock to change bitmap location
  raid5: fix incorrectly counter of conf->empty_inactive_list_nr
  raid10: increment write counter after bio is split
2016-08-30 11:24:04 -07:00
Linus Torvalds
0cf21c6609 NFS client bugfixes for 4.8
Highlights include:
 
 Stable patches:
 - Fix a refcount leak in nfs_callback_up_net
 - Fix an Oopsable condition when the flexfile pNFS driver connection to
   the DS fails
 - Fix an Oopsable condition in NFSv4.1 server callback races
 - Ensure pNFS clients stop doing I/O to the DS if their lease has expired,
   as required by the NFSv4.1 protocol
 
 Bugfixes:
 - Fix potential looping in the NFSv4.x migration code
 - Patch series to close callback races for OPEN, LAYOUTGET and LAYOUTRETURN
 - Silence WARN_ON when NFSv4.1 over RDMA is in use
 - Fix a LAYOUTCOMMIT race in the pNFS/blocks client
 - Fix pNFS timeout issues when the DS fails
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Merge tag 'nfs-for-4.8-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client bugfixes from Trond Myklebust:
 "Highlights include:

  Stable patches:
   - Fix a refcount leak in nfs_callback_up_net
   - Fix an Oopsable condition when the flexfile pNFS driver connection
     to the DS fails
   - Fix an Oopsable condition in NFSv4.1 server callback races
   - Ensure pNFS clients stop doing I/O to the DS if their lease has
     expired, as required by the NFSv4.1 protocol

  Bugfixes:
   - Fix potential looping in the NFSv4.x migration code
   - Patch series to close callback races for OPEN, LAYOUTGET and
     LAYOUTRETURN
   - Silence WARN_ON when NFSv4.1 over RDMA is in use
   - Fix a LAYOUTCOMMIT race in the pNFS/blocks client
   - Fix pNFS timeout issues when the DS fails"

* tag 'nfs-for-4.8-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFSv4.x: Fix a refcount leak in nfs_callback_up_net
  NFS4: Avoid migration loops
  pNFS/flexfiles: Fix an Oopsable condition when connection to the DS fails
  NFSv4.1: Remove obsolete and incorrrect assignment in nfs4_callback_sequence
  NFSv4.1: Close callback races for OPEN, LAYOUTGET and LAYOUTRETURN
  NFSv4.1: Defer bumping the slot sequence number until we free the slot
  NFSv4.1: Delay callback processing when there are referring triples
  NFSv4.1: Fix Oopsable condition in server callback races
  SUNRPC: Silence WARN_ON when NFSv4.1 over RDMA is in use
  pnfs/blocklayout: update last_write_offset atomically with extents
  pNFS: The client must not do I/O to the DS if it's lease has expired
  pNFS: Handle NFS4ERR_OLD_STATEID correctly in LAYOUTSTAT calls
  pNFS/flexfiles: Set reasonable default retrans values for the data channel
  NFS: Allow the mount option retrans=0
  pNFS/flexfiles: Fix layoutstat periodic reporting
2016-08-30 11:14:02 -07:00
Josh Poimboeuf
0d025d271e mm/usercopy: get rid of CONFIG_DEBUG_STRICT_USER_COPY_CHECKS
There are three usercopy warnings which are currently being silenced for
gcc 4.6 and newer:

1) "copy_from_user() buffer size is too small" compile warning/error

   This is a static warning which happens when object size and copy size
   are both const, and copy size > object size.  I didn't see any false
   positives for this one.  So the function warning attribute seems to
   be working fine here.

   Note this scenario is always a bug and so I think it should be
   changed to *always* be an error, regardless of
   CONFIG_DEBUG_STRICT_USER_COPY_CHECKS.

2) "copy_from_user() buffer size is not provably correct" compile warning

   This is another static warning which happens when I enable
   __compiletime_object_size() for new compilers (and
   CONFIG_DEBUG_STRICT_USER_COPY_CHECKS).  It happens when object size
   is const, but copy size is *not*.  In this case there's no way to
   compare the two at build time, so it gives the warning.  (Note the
   warning is a byproduct of the fact that gcc has no way of knowing
   whether the overflow function will be called, so the call isn't dead
   code and the warning attribute is activated.)

   So this warning seems to only indicate "this is an unusual pattern,
   maybe you should check it out" rather than "this is a bug".

   I get 102(!) of these warnings with allyesconfig and the
   __compiletime_object_size() gcc check removed.  I don't know if there
   are any real bugs hiding in there, but from looking at a small
   sample, I didn't see any.  According to Kees, it does sometimes find
   real bugs.  But the false positive rate seems high.

3) "Buffer overflow detected" runtime warning

   This is a runtime warning where object size is const, and copy size >
   object size.

All three warnings (both static and runtime) were completely disabled
for gcc 4.6 with the following commit:

  2fb0815c9e ("gcc4: disable __compiletime_object_size for GCC 4.6+")

That commit mistakenly assumed that the false positives were caused by a
gcc bug in __compiletime_object_size().  But in fact,
__compiletime_object_size() seems to be working fine.  The false
positives were instead triggered by #2 above.  (Though I don't have an
explanation for why the warnings supposedly only started showing up in
gcc 4.6.)

So remove warning #2 to get rid of all the false positives, and re-enable
warnings #1 and #3 by reverting the above commit.

Furthermore, since #1 is a real bug which is detected at compile time,
upgrade it to always be an error.

Having done all that, CONFIG_DEBUG_STRICT_USER_COPY_CHECKS is no longer
needed.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-30 10:10:21 -07:00
Linus Torvalds
d8dc020cac Merge branch 'for-4.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata
Pull libata fixes from Tejun Heo:
 "Two libata driver specific fixes for v4.8-rc4.  Nothing too scary"

* 'for-4.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  pata_ninja32: Avoid corrupting status flags
  ahci: disable correct irq for dummy ports
2016-08-30 09:44:11 -07:00
Linus Torvalds
748e7fc209 Merge branch 'for-4.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:
 "Two fixes for cgroup.

   - There still was a hole in enforcing cpuset rules, fixed by Li.

   - The recent switch to global percpu_rwseom for threadgroup locking
     revealed a couple issues in how percpu_rwsem is implemented and
     used by cgroup.  Balbir found that the read locking section was too
     wide unnecessarily including operations which can often depend on
     IOs.  With percpu_rwsem updates (coming through a different tree)
     and reduction of read locking section, all the reported locking
     latency issues, including the android one, are resolved.

  It looks like we can keep global percpu_rwsem locking for now.  If
  there actually are cases which can't be resolved, we can go back to
  more complex per-signal_struct locking"

* 'for-4.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: reduce read locked section of cgroup_threadgroup_rwsem during fork
  cpuset: make sure new tasks conform to the current config of the cpuset
2016-08-30 09:31:59 -07:00