When we change cpuset.memory_spread_{page,slab}, cpuset will flip
PF_SPREAD_{PAGE,SLAB} bit of tsk->flags for each task in that cpuset.
This should be done using atomic bitops, but currently we don't,
which is broken.
Tetsuo reported a hard-to-reproduce kernel crash on RHEL6, which happened
when one thread tried to clear PF_USED_MATH while at the same time another
thread tried to flip PF_SPREAD_PAGE/PF_SPREAD_SLAB. They both operate on
the same task.
Here's the full report:
https://lkml.org/lkml/2014/9/19/230
To fix this, we make PF_SPREAD_PAGE and PF_SPREAD_SLAB atomic flags.
v4:
- updated mm/slab.c. (Fengguang Wu)
- updated Documentation.
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Cc: Kees Cook <keescook@chromium.org>
Fixes: 950592f7b9 ("cpusets: update tasks' page/slab spread flags in time")
Cc: <stable@vger.kernel.org> # 2.6.31+
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Zefan Li <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This will simplify code when we add new flags.
v3:
- Kees pointed out that no_new_privs should never be cleared, so we
shouldn't define task_clear_no_new_privs(). we define 3 macros instead
of a single one.
v2:
- updated scripts/tags.sh, suggested by Peter
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Zefan Li <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Commit 1d4457f999 ("sched: move no_new_privs into new atomic flags")
defined PFA_NO_NEW_PRIVS as hexadecimal value, but it is confusing
because it is used as bit number. Redefine it as decimal bit number.
Note this changes the bit position of PFA_NOW_NEW_PRIVS from 1 to 0.
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Kees Cook <keescook@chromium.org>
[ lizf: slightly modified subject and changelog ]
Signed-off-by: Zefan Li <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
cgroup_pidlist_start() holds cgrp->pidlist_mutex and then calls
pidlist_array_load(), and cgroup_pidlist_stop() releases the mutex.
It is wrong that we release the mutex in the failure path in
pidlist_array_load(), because cgroup_pidlist_stop() will be called
no matter if cgroup_pidlist_start() returns errno or not.
Fixes: 4bac00d16a
Cc: <stable@vger.kernel.org> # 3.14+
Signed-off-by: Zefan Li <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Run these two scripts concurrently:
for ((; ;))
{
mkdir /cgroup/sub
rmdir /cgroup/sub
}
for ((; ;))
{
echo $$ > /cgroup/sub/cgroup.procs
echo $$ > /cgroup/cgroup.procs
}
A kernel bug will be triggered:
BUG: unable to handle kernel NULL pointer dereference at 00000038
IP: [<c10bbd69>] cgroup_put+0x9/0x80
...
Call Trace:
[<c10bbe19>] cgroup_kn_unlock+0x39/0x50
[<c10bbe91>] cgroup_kn_lock_live+0x61/0x70
[<c10be3c1>] __cgroup_procs_write.isra.26+0x51/0x230
[<c10be5b2>] cgroup_tasks_write+0x12/0x20
[<c10bb7b0>] cgroup_file_write+0x40/0x130
[<c11aee71>] kernfs_fop_write+0xd1/0x160
[<c1148e58>] vfs_write+0x98/0x1e0
[<c114934d>] SyS_write+0x4d/0xa0
[<c16f656b>] sysenter_do_call+0x12/0x12
We clear cgrp->kn->priv in the end of cgroup_rmdir(), but another
concurrent thread can access kn->priv after the clearing.
We should move the clearing to css_release_work_fn(). At that time
no one is holding reference to the cgroup and no one can gain a new
reference to access it.
v2:
- move RCU_INIT_POINTER() into the else block. (Tejun)
- remove the cgroup_parent() check. (Tejun)
- update the comment in css_tryget_online_from_dir().
Cc: <stable@vger.kernel.org> # 3.15+
Reported-by: Toralf Förster <toralf.foerster@gmx.de>
Signed-off-by: Zefan Li <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Kernel command line parameter cgroup__DEVEL__legacy_files_on_dfl forces
legacy cgroup files to show up on default hierarhcy if susbsystem does
not have any files defined for default hierarchy.
But this seems to be working only if legacy files are defined in
ss->legacy_cftypes. If one adds some cftypes later using
cgroup_add_legacy_cftypes(), these files don't show up on default
hierarchy. Update the function accordingly so that the dynamically
added legacy files also show up in the default hierarchy if the target
subsystem is also using the base legacy files for the default
hierarchy.
tj: Patch description and comment updates.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
/proc/<pid>/cgroup contains one cgroup path on each line. If cgroup names are
allowed to contain "\n", applications cannot parse /proc/<pid>/cgroup safely.
Signed-off-by: Alban Crequy <alban.crequy@collabora.co.uk>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org
Pull x86 platform driver updates from Matthew Garrett:
"A moderate number of changes, but nothing awfully significant.
A lot of const cleanups, some reworking and additions to the rfkill
quirks in the asus driver, a new driver for generating falling laptop
events on Toshibas and some misc fixes.
Maybe vendors have stopped inventing things"
* 'for_linus' of git://cavan.codon.org.uk/platform-drivers-x86: (41 commits)
platform/x86: Enable build support for toshiba_haps
Documentation: Add file about toshiba_haps module
platform/x86: Toshiba HDD Active Protection Sensor
asus-nb-wmi: Add wapf4 quirk for the U32U
alienware-wmi: make hdmi_mux enabled on case-by-case basis
ideapad-laptop: Constify DMI table and other r/o variables
asus-nb-wmi.c: Rename x401u quirk to wapf4
compal-laptop: correct invalid hwmon name
toshiba_acpi: Add Qosmio X75-A to the alt keymap dmi list
toshiba_acpi: Add extra check to backlight code
Fix log message about future removal of interface
ideapad-laptop: Disable touchpad interface on Yoga models
asus-nb-wmi: Add wapf4 quirk for the X550CC
intel_ips: Make ips_mcp_limits variables static
thinkpad_acpi: Mark volume_alsa_control_{vol,mute} as __initdata
fujitsu-laptop: Mark fujitsu_dmi_table[] DMI table as __initconst
hp-wmi: Add missing __init annotations to initialization code
hp_accel: Constify ACPI and DMI tables
fujitsu-tablet: Mark DMI callbacks as __init code
dell-laptop: Mark dell_quirks[] DMI table as __initconst
...
Pull idle update from Len Brown:
"Two Intel-platform-specific updates to intel_idle, and a cosmetic
tweak to the turbostat utility"
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
tools/power turbostat: tweak whitespace in output format
intel_idle: Broadwell support
intel_idle: Disable Baytrail Core and Module C6 auto-demotion
value (we don't fail unknown module params any more, just warn).
Cheers,
Rusty.
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Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull module fix from Rusty Russell:
"Nasty potential bug if someone uses a known module param with an
invalid value (we don't fail unknown module params any more, just
warn)"
* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
module: Clean up ro/nx after early module load failures
Pull virtio-rng update from Amit Shah:
"Add derating factor for use by hwrng core
Sending directly to you with the commit log changes Ted Ts'o pointed
out. Not sure if Rusty's back after his travel, but this already has
his s-o-b"
* 'rng-queue' of git://git.kernel.org/pub/scm/linux/kernel/git/amit/virtio:
virtio: rng: add derating factor for use by hwrng core
Pull btrfs updates from Chris Mason:
"These are all fixes I'd like to get out to a broader audience.
The biggest of the bunch is Mark's quota fix, which is also in the
SUSE kernel, and makes our subvolume quotas dramatically more
accurate.
I've been running xfstests with these against your current git
overnight, but I'm queueing up longer tests as well"
* 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: disable strict file flushes for renames and truncates
Btrfs: fix csum tree corruption, duplicate and outdated checksums
Btrfs: Fix memory corruption by ulist_add_merge() on 32bit arch
Btrfs: fix compressed write corruption on enospc
btrfs: correctly handle return from ulist_add
btrfs: qgroup: account shared subtrees during snapshot delete
Btrfs: read lock extent buffer while walking backrefs
Btrfs: __btrfs_mod_ref should always use no_quota
btrfs: adjust statfs calculations according to raid profiles
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Merge tag 'locks-v3.17-2' of git://git.samba.org/jlayton/linux
Pull file locking bugfixes from Jeff Layton:
"Most of these patches are to fix a long-standing regression that crept
in when the BKL was removed from the file-locking code. The code was
converted to use a conventional spinlock, but some fl_release_private
ops can block and you can end up sleeping inside the lock.
There's also a patch to make /proc/locks show delegations as 'DELEG'"
* tag 'locks-v3.17-2' of git://git.samba.org/jlayton/linux:
locks: update Locking documentation to clarify fl_release_private behavior
locks: move locks_free_lock calls in do_fcntl_add_lease outside spinlock
locks: defer freeing locks in locks_delete_lock until after i_lock has been dropped
locks: don't reuse file_lock in __posix_lock_file
locks: don't call locks_release_private from locks_copy_lock
locks: show delegations as "DELEG" in /proc/locks
Pull aio updates from Ben LaHaise.
* git://git.kvack.org/~bcrl/aio-next:
aio: use iovec array rather than the single one
aio: fix some comments
aio: use the macro rather than the inline magic number
aio: remove the needless registration of ring file's private_data
aio: remove no longer needed preempt_disable()
aio: kill the misleading rcu read locks in ioctx_add_table() and kill_ioctx()
aio: change exit_aio() to load mm->ioctx_table once and avoid rcu_read_lock()
Makefile and Kconfig build support patch for the newly introduced
kernel module toshiba_haps.
Signed-off-by: Azael Avalos <coproscefalo@gmail.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
This patch provides information about the Toshiba HDD
Active Protection Sensor driver module toshiba_haps.
Signed-off-by: Azael Avalos <coproscefalo@gmail.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
This driver adds support for the built-in accelereometer found
on recent Toshiba laptops with HID TOS620A.
This driver receives ACPI notify events 0x80 when the sensor
detects a sudden move or a harsh vibration, as well as an
ACPI notify event 0x81 whenever the movement or vibration has
been stabilized.
Also provides sysfs entries to get/set the desired protection
level and reseting the HDD protection interface.
Signed-off-by: Azael Avalos <coproscefalo@gmail.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Not all HW supporting WMAX method will support the HDMI mux feature.
Explicitly quirk the HW that does support it.
Signed-off-by: Mario Limonciello <mario_limonciello@dell.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Constify the rfkill_blacklist[] DMI table, the ideapad_rfk_data[] table
and the ideapad_attribute_group attribute group. There's no need to have
them writeable during runtime.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Ike Panhc <ike.pan@canonical.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
The actual x401u does not use the so named x401u quirk but the x55u quirk.
All that the x401u quirk does it setting wapf to 4, so rename it to wapf4 to
stop the confusion.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Change the name of the hwmon interface from "compal-laptop" to "compal".
A dash is an invalid character for a hwmon name and caused the call to
hwmon_device_register_with_groups() to fail.
Signed-off-by: Roald Frederickx <roald.frederickx@gmail.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
The Toshiba Qosmio X75-A series models also come with
the new keymap layout.
This patch adds this model to the alt_keymap_dmi list,
along with an extra key found on these models.
Signed-off-by: Azael Avalos <coproscefalo@gmail.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Some Toshiba models (most notably Qosmios) come with an
incomplete backlight method where the AML code doesn't
check for write or read commands and always returns
HCI_SUCCESS and the actual brightness (and in some
cases the max brightness), thus allowing the backlight
interface to be registered without write support.
This patch changes the set_lcd_brightness function,
checking the returned values for values greater than
zero to avoid registering a broken backlight interface.
Signed-off-by: Azael Avalos <coproscefalo@gmail.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
If this is going away, it won't be in 2012.
Signed-off-by: Martin Kepplinger <martink@posteo.de>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Yoga models don't offer touchpad ctrl through the ideapad interface, causing
ideapad_sync_touchpad_state to send wrong touchpad enable/disable events.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
These variables don't need to be visible outside of this compilation
unit, make them static.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Mark volume_alsa_control_vol and volume_alsa_control_mute as __initdata,
as snd_ctl_new1() will copy the relevant parts, so there is no need to
keep the master copies around after initialization.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Henrique de Moraes Holschuh <ibm-acpi@hmh.eng.br>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
The DMI table is only ever used during initialization. Mark it as
__initconst so its memory can be released afterwards -- roughly 1.5 kB.
In turn, the callback functions can be marked with __init, too.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Jonathan Woithe <jwoithe@just42.net>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
These functions are only called from other initialization routines, so
can be marked __init, too.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Constify the lis3lv02d_device_ids[] ACPI and the lis3lv02d_dmi_ids[] DMI
tables. There's no need to have them writeable during runtime.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Eric Piel <eric.piel@tremplin-utc.net>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
The DMI table is already marked as __initconst, so can be the callback
functions as they're only used in that context.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Robert Gerlach <khnz@gmx.de>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
The dell_quirks[] DMI table is only ever used during initialization.
Mark it as __initconst so its memory can be released afterwards --
roughly 5.7 kB. In turn, the callback function can be marked with
__init, too.
Also the touchpad_led_init() function can be marked __init as it's only
referenced from dell_init() -- an __init function.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Constify the asus_quirks[] DMI table. There's no need to have it
writeable during runtime.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Corentin Chary <corentin.chary@gmail.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Quite a lot of code and data of acer-wmi.c is only ever used during
initialization. Mark those accordingly -- and constify, where
appropriate -- so the memory can be released afterwards.
All in all those changes move ~10 kB of code and data to the .init
sections, marking them for release after initialization has finished.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: "Lee, Chun-Yi" <jlee@suse.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Constify the asus_quirks[] DMI table. There's no need to have it
writeable during runtime.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Corentin Chary <corentin.chary@gmail.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
The DMI table is only ever used during initialization. Mark it as
__initconst so its memory can be released appropriately. In turn, the
callback function can be marked with __init, too.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Encapsulate acer_suspend() and acer_resume with #ifdef CONFIG_PM_SLEEP
to get rid of the following warnings:
../acer-wmi.c:2046:12: warning: ‘acer_suspend’ defined but not used [-Wunused-function]
../acer-wmi.c:2068:12: warning: ‘acer_resume’ defined but not used [-Wunused-function]
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: "Lee, Chun-Yi" <jlee@suse.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
sparse_keymap_setup() will make a copy of the keymap, so we can release
the master copy after initialization.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: "Lee, Chun-Yi" <jlee@suse.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
The repo on kernel.org is no longer available but has a replacement at
cavan.codon.org.uk.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
This patch removes the null test on block. block is initialized at the
beginning of the function to &wblock->gblock. Since wblock is
dereferenced prior to the null test, wblock must be a valid pointer,
and &wblock->gblock cannot be null.
The following Coccinelle script is used for detecting the change:
@r@
expression e,f;
identifier g,y;
statement S1,S2;
@@
*e = &f->g
<+...
f->y
...+>
*if (e != NULL || ...)
S1 else S2
Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
As reported here: https://bugs.launchpad.net/bugs/1277959
the X550CL needs wapf=4 too.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
BIOS won't light on the wifi-led after S3, so asus-wmi driver needs to
control the wifi and wifi-led status.
But, it'll lead to bt status error if asus-wmi driver controls bt as well.
So, for X200CA, asus-wmi driver controls wifi status only and have to set
wapf to 1.
Signed-off-by: AceLan Kao <acelan.kao@canonical.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Wifi will be controlled by asus-wmi driver when wapf > 0
So, controls the wifi-led when wapf > 0
Signed-off-by: AceLan Kao <acelan.kao@canonical.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
When bl_power support got added to asus-wmi, the error handling for it was
written to ignore -ENODEV, to avoid not registering a backlight interface for
models which have no bl_power control, but do have brightness control.
At the same time the error handling for brightness_max was modified to do the
same, this is wrong, when there is no brightness_max asus-wmi should not
register a backlight interface.
Note the caller of asus_wmi_backlight_init already special cases -ENODEV,
and will not cause the wmi driver regristration to fail because of a
-ENODEV return from asus_wmi_backlight_init.
https://bugzilla.redhat.com/show_bug.cgi?id=1097436
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Some Asus motherboards for desktop PC-s export an acpi-video interface
advertising backlight support. Test the dmi chassis-type and tell acpi-video
to not register a backlight interface on desktops.
https://bugzilla.redhat.com/show_bug.cgi?id=1097436
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
