One small bug fix, plus a rename of all the ST Ericsson regulators in
the device tree since all the device trees had been written with
different names and some infelicities in the test proceedures meant that
the device tree code had apparently never actually been run against the
upstream device tree.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.12 (GNU/Linux)
iQIcBAABAgAGBQJP3hQ6AAoJEBus8iNuMP3dbToP/iFWsPR14SRqtmv5N0AEftyD
SdDYZRdWAlwSunRkZhE12Kk1+q2wpxYmG2rJgYHJWw2Mk4biaW6XHKKGYjKxJ0C6
WdskxhAs+Pl0KFqq0Z2+zrWEjSFMqkFHQrt3zfSHFb/ju3Us6jn8VaxR0i+WlWSJ
IIZRvHPRU0et+BXuVUwcF6JOPNnoWlsFVugCBH7r56mCgPkU78NTKycUD6oprQvy
BIMrHek5TWK39a6oHICWGLgQBxMKDNz+91yq9+4mIjxE84XcsAGuZcoDcbpNHtbA
YmusSqKHQ0ShZVDvGj58xntbmh0SjqC/8CnVrzgXGOHaHisHiErZ/1y4sEiLrPnL
o/6/42wyO+DKfftAOYOydks4AfOFPUJsfpvR/wDFvVSwwCSYJCwxP0ZxfQ9GGGcl
IH8oLb84F3uHqg7De/zCW5+Qsw+EUxq76K+lnKx8vab5mJWtwxl9kMOsttYjr/f0
8/q5ndln0C3rnAoB6hPMqE7bCswDkk3dXuAbln3OIkbhNglpSsyU5R+b2h5hugTG
oENPkMTYFf8dRJ1hZsWrKM9HZaHWgxUe5KcEMyYEel3qdiYHWjmprnOeNHNo/u/o
uG4tVlHO0rvOZpRbuvzc72Uonyri/oTfJ3b5Z9ZkRhmd/9pV83jJx12HlXxQoIae
nvHtEhp2dKYVBIXfc+0s
=NS0T
-----END PGP SIGNATURE-----
Merge tag 'regulator-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator
Pull regulator fixes from Mark Brown:
"One small bug fix, plus a rename of all the ST Ericsson regulators in
the device tree since all the device trees had been written with
different names and some infelicities in the test proceedures meant
that the device tree code had apparently never actually been run
against the upstream device tree."
* tag 'regulator-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
regulator: Change db8500-prcmu match names to reflect Device Tree
regulator: Change ab8500 match names to reflect Device Tree
regulator: Fix the s5m8767a problem of the division by null
add_virtual_intf() needs to return an ERR_PTR(), instead of NULL,
on errors, otherwise cfg80211 will crash.
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
"qual" used to be declared on the stack, but then in 998a5a7d6a ("airo:
reduce stack memory footprint") we made it dynamically allocated.
Unfortunately the memcpy() here was missed and it's still copying stack
memory instead of the data that we want. In other words, "&qual" should
be "qual".
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When running heavy traffic we stop the tx queue if the pending
packet count reaches certain threshold. Later, the tx queue should
be woken up as soon as the packet count falls below the threshold.
Current code wakes TX queue up on STA interface only. Removing the
check for STA interface will allow both STA and AP interfaces to
resume transmit when tx_pending count becomes low.
Signed-off-by: Avinash Patil <patila@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
spin_unlock_bh(&txq->lock) already disables softirqs so we don't want
to do it here. Fixes smatch warnings:
drivers/net/wireless/ath/ath5k/base.c:1048 ath5k_drain_tx_buffs() error: double lock 'bottom_half:'
drivers/net/wireless/ath/ath5k/base.c:1056 ath5k_drain_tx_buffs() error: double unlock 'bottom_half:'
Reported-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
After setup_frame_info has been called, only info->control.rates is still
valid, other control fields have been overwritten by the ath_frame_info
data. Move the access to info->control.vif for checking short preamble
to setup_frame_info before it gets overwritten.
This regression was introduced in commit d47a61aa
"ath9k: Fix multi-VIF BSS handling"
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Reported-by: Thomas Hühn <thomas@net.t-labs.tu-berlin.de>
Acked-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Cc: stable@vger.kernel.org [3.4]
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The rate pointer variable for a rate series is used in a loop before it is
initialized. This went unnoticed because it was used earlier for the RTS/CTS
rate. This bug can lead to the wrong PHY type being passed to the
duration calculation function.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Cc: stable@kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The call to try_module_get() dereferences ld_type outside the
spin locks, which means that it may be pointing to garbage if
a module unload was in progress.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
At the moment we call kvmppc_pin_guest_page() in kvmppc_update_vpa()
with two spinlocks held: the vcore lock and the vcpu->vpa_update_lock.
This is not good, since kvmppc_pin_guest_page() calls down_read() and
get_user_pages_fast(), both of which can sleep. This bug was introduced
in 2e25aa5f ("KVM: PPC: Book3S HV: Make virtual processor area
registration more robust").
This arranges to drop those spinlocks before calling
kvmppc_pin_guest_page() and re-take them afterwards. Dropping the
vcore lock in kvmppc_run_core() means we have to set the vcore_state
field to VCORE_RUNNING before we drop the lock, so that other vcpus
won't try to run this vcore.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
On a freescale imx6q platform, a hardware phy chip KSZ9021 is
recognized as a KS8001 chip by the current driver like this:
eth0: Freescale FEC PHY driver [Micrel KS8001 or KS8721]
KSZ9021 has phy_id 0x00221610, while KSZ8001 has phy_id
0x0022161a, the current phy_id_mask (0x00fffff0/0x00ffff10) can't
distinguish them. So change phy_id_mask to resolve this problem.
Although the micrel datasheet says that the 4 LSB of phyid2 register
contains the chip revision number and the current driver is designed
to follow this rule, in reality the chip implementation doesn't follow
it.
Cc: David J. Choi <david.choi@micrel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Hui Wang <jason77.wang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/sctp/protocol.c: In function ‘sctp_addr_wq_timeout_handler’:
net/sctp/protocol.c:676: warning: label ‘free_next’ defined but not used
Signed-off-by: Daniel Halperin <dhalperi@cs.washington.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Vendor-specific events shall be processed in driver and not sent
to bluetooth stack where they screw up HCI command countings.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
/proc/net/ipv6_route reflects the contents of fib_table_hash. The proc
handler is installed in ip6_route_net_init() whereas fib_table_hash is
allocated in fib6_net_init() _after_ the proc handler has been installed.
This opens up a short time frame to access fib_table_hash with its pants
down.
Move the registration of the proc files to a later point in the init
order to avoid the race.
Tested :-)
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
This solves a section mismatch warning. I hadn't noticed this before,
because my compiler was inlining tegra_cpu_reset_handler_enable() inside
tegra_cpu_reset_handler_init(), which is already __init, but I switched
compilers and it stopped doing that.
Cc: <stable@kernel.org> # v3.4
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
extcon_dev_unregister(info->edev) doest not free info->edev, we need to call
kfree(info->edev) here.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add missing platform_set_drvdata() in gpio_extcon_probe(), otherwise calling
platform_get_drvdata in gpio_extcon_remove() returns NULL.
Also add missing free_irq call in gpio_extcon_remove().
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, the index of "Dock-desk" and "Dock-card" are the same.
Thus the latter one overrides the first one.
Then we have problem when calling extcon_find_cable_index() because
edev->supported_cable[7] only matches "Dock-card".
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixed the size of the V4L2_CID_COLORFX control cluster.
Prior to this fix V4L2_CID_ROTATE was also icluded in
the cluster preventing application from enabling rotation.
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Fixes the following error:
ERROR: open brace '{' following enum go on the same line
+enum MFC_SHM_OFS
+{
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Fixed s_ctrl function when setting the following controls:
- V4L2_CID_MPEG_VIDEO_DECODER_MPEG4_DEBLOCK_FILTER
- V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY
Signed-off-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Image size for MFC encoder should have size between
8x4 and 1920x1080 with even width and height.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Patch corrects definition of H264 level control and
changes bare numbers to enums in two other cases.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
The mem2mem_testdev allows multiple instances to be opened in parallel.
Source and destination queue data are being shared between all
instances, which can lead to kernel oops due to race conditions (most
likely to happen inside device_run()).
Attached patch fixes mentioned problem by storing queue data per device
context.
Signed-off-by: Tomasz Moń <desowin@gmail.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Fixed the code copying timecode/timestamp to corresponding
frames between OUTPUT and CAPTURE.
Signed-off-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
When we fixed the race between atomic_dec and css_refcnt, we missed
the fact that css_refcnt internally subtracts CSS_DEACT_BIAS to get
the actual reference count. This can potentially cause a refcount leak
if __css_put races with cgroup_clear_css_refs.
Signed-off-by: Salman Qazi <sqazi@google.com>
Acked-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Pull EDAC fixes from Mauro Carvalho Chehab.
* git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-edac:
edac: Do alignment logic properly in edac_align_ptr()
mpc85xx_edac: fix error: too few arguments to function 'edac_mc_alloc'
edac: fix the error about memory type detection on SandyBridge
edac: avoid mce decoding crash after edac driver unloaded
Fix an incorrect modulation type bitmask. This allows QAM256 also to be
correctly reported.
Signed-off-by: Janne Huttunen <jahuttun@gmail.com>
Acked-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Pull a 9p bugfix from Eric Van Hensbergen.
* 'v9fs-devel' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
9p: BUG before corrupting memory
Pull a crypto fix from Herbert Xu:
"This push fixes another bug in the atmel-rng that made it produce
completely useless output."
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
hwrng: atmel-rng - fix data valid check
Pull hwmon subsystem fixes from Jean Delvare.
* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
hwmon: (coretemp) Drop needless initialization
hwmon: (coretemp) Document TjMax for 3rd generation i5/i7 processors
hwmon: (coretemp) Improve support for TjMax detection on Atom CPUs
hwmon: (coretemp) Add support for Atom D2000 and N2000 series CPU models
hwmon: (coretemp) Improve support of recent Atom CPU models
The asm-generic/bug.h __ASSEMBLY__ guarding is completely bogus, which
tripped up the powerpc build when the kernel.h include was added:
In file included from include/asm-generic/bug.h:5:0,
from arch/powerpc/include/asm/bug.h:127,
from arch/powerpc/kernel/head_64.S:31:
include/linux/kernel.h:44:0: warning: "ALIGN" redefined [enabled by default]
include/linux/linkage.h:57:0: note: this is the location of the previous definition
include/linux/sysinfo.h: Assembler messages:
include/linux/sysinfo.h:7: Error: Unrecognized opcode: `struct'
include/linux/sysinfo.h:8: Error: Unrecognized opcode: `__kernel_long_t'
Moving the __ASSEMBLY__ guard up and stashing the kernel.h include under
it fixes this up, as well as covering the case the original fix was
attempting to handle.
Tested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When the READABLE_ASM cc-option tests were added they were done so prior
to the arch Makefile include, resulting in cc-option being run on the
host cc instead of the factoring in the cross prefix set up by the
architecture.
This bumps the include back up so that cc-option actually runs on the
compiler that we're building with.
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix:
emc2103.c: In function set_pwm_enable:
emc2103.c:463:12: warning: conf_reg may be used uninitialized in this function
by checking the return value from read_u8_from_i2c(). This fixes a real problem,
as conf_reg is really uninitialized if read_u8_from_i2c returns an error.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Robert Coulson <robert.coulson@ericsson.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Key lookups may call read_smc() with a fixed-length key string,
and if the lookup fails, trailing stack content may appear in the
kernel log. Fixed with this patch.
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Cc: stable@vger.kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This simply shows a little warning if the board does not have remote
control support. This should make it easier for users to see if they
have misconfigured their system or if the driver simply does not have
rc-support for their card (yet).
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
The Cinergy HTC Stick HD uses the same remote control as the TerraTec
Cinergy XS products. Thus the same keymap could be re-used.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Commit 5963e317b1 ("ftrace/x86: Do not change stacks in DEBUG when
calling lockdep") prevented lockdep calls from the int3 breakpoint handler
from reseting the stack if a function that was called was in the process
of being converted for tracing and had a breakpoint on it. The idea is,
before calling the lockdep code, do a load_idt() to the special IDT that
kept the breakpoint stack from reseting. This worked well as a quick fix
for this kernel release, until a certain config caused a lockup in the
function tracer start up tests.
Investigating it, I found that the load_idt that was used to prevent
the int3 from changing stacks was itself being traced!
Even though the config had CONFIG_OPTIMIZE_INLINING disabled, and
all 'inline' tags were set to always inline, there were still cases that
it did not inline! This was caused by CONFIG_PARAVIRT_GUEST, where it
would add a pointer to the native_load_idt() which made that function
to be traced.
Commit 45959ee7aa ("ftrace: Do not function trace inlined functions")
only touched the 'inline' tags when CONFIG_OPMITIZE_INLINING was enabled.
PARAVIRT_GUEST shows that this was not enough and we need to also
mark always_inline with notrace as well.
Reported-by: Fengguang Wu <wfg@linux.intel.com>
Tested-by: Fengguang Wu <wfg@linux.intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Currently there is a 'chicken and egg' issue when the DS is also the mounted
MDS. The nfs_match_client() reference from nfs4_set_ds_client bumps the
cl_count, the nfs_client is not freed at umount, and nfs4_deviceid_purge_client
is not called to dereference the MDS usage of a deviceid which holds a
reference to the DS nfs_client. The result is the umount program returns,
but the nfs_client is not freed, and the cl_session hearbeat continues.
The MDS (and all other nfs mounts) lose their last nfs_client reference in
nfs_free_server when the last nfs_server (fsid) is umounted.
The file layout DS lose their last nfs_client reference in destroy_ds
when the last deviceid referencing the data server is put and destroy_ds is
called. This is triggered by a call to nfs4_deviceid_purge_client which
removes references to a pNFS deviceid used by an MDS mount.
The fix is to track how many pnfs enabled filesystems are mounted from
this server, and then to purge the device id cache once that count reaches
zero.
Reported-by: Jorge Mora <Jorge.Mora@netapp.com>
Reported-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This reverts commit d509835e32. That commit
breaks support for the generic pass-through mode in the driver for formats,
not natively supported by it. Besides due to a merge conflict it also breaks
driver compilation:
drivers/media/video/mx2_camera.c: In function 'mx2_camera_set_bus_param':
drivers/media/video/mx2_camera.c:937: error: 'pixfmt' undeclared (first use in this function)
drivers/media/video/mx2_camera.c:937: error: (Each undeclared identifier is reported only once
drivers/media/video/mx2_camera.c:937: error: for each function it appears in.)
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Javier Martin <javier.martin@vista-silicon.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
The asserts here never check anything because it uses '|' instead of
'&'. Now if the flags are not set it prints a warning a a stack trace.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
1a77b127ae (OMAP : SPI : use devm_* functions) converted the SPI
device controller state to use devm_kzalloc(). Unfortunately, this
is used against an unbound struct device, which results in the
following when the device is bound to its driver:
------------[ cut here ]------------
WARNING: at /home/rmk/git/linux-rmk/drivers/base/dd.c:257 driver_probe_device+0x78/0x21c()
Modules linked in:
Backtrace:
[<c0017d0c>] (dump_backtrace+0x0/0x10c) from [<c033e208>] (dump_stack+0x18/0x1c) r7:00000000 r6:c01ff28c r5:c040050c r4:00000101
[<c033e1f0>] (dump_stack+0x0/0x1c) from [<c00337ec>] (warn_slowpath_common+0x58/0x70)
[<c0033794>] (warn_slowpath_common+0x0/0x70) from [<c0033828>] (warn_slowpath_null+0x24/0x2c)
[<c0033804>] (warn_slowpath_null+0x0/0x2c) from [<c01ff28c>] (driver_probe_device+0x78/0x21c)
[<c01ff214>] (driver_probe_device+0x0/0x21c) from [<c01ff49c>] (__driver_attach+0x6c/0x90)
[<c01ff430>] (__driver_attach+0x0/0x90) from [<c01fda70>] (bus_for_each_dev+0x58/0x98)
[<c01fda18>] (bus_for_each_dev+0x0/0x98) from [<c01ff0f4>] (driver_attach+0x20/0x28)
[<c01ff0d4>] (driver_attach+0x0/0x28) from [<c01fe2f4>] (bus_add_driver+0xb4/0x230)
[<c01fe240>] (bus_add_driver+0x0/0x230) from [<c01ffb24>] (driver_register+0xac/0x138)
[<c01ffa78>] (driver_register+0x0/0x138) from [<c0215d4c>] (spi_register_driver+0x4c/0x60)
[<c0215d00>] (spi_register_driver+0x0/0x60) from [<c045414c>] (ks8851_init+0x14/0x1c)
[<c0454138>] (ks8851_init+0x0/0x1c) from [<c0008770>] (do_one_initcall+0x9c/0x164)
[<c00086d4>] (do_one_initcall+0x0/0x164) from [<c0436410>] (kernel_init+0x128/0x210)
[<c04362e8>] (kernel_init+0x0/0x210) from [<c0038754>] (do_exit+0x0/0x72c)
---[ end trace 4dcda79f5e89dd84 ]---
ks8851 spi1.0: message enable is 0
ks8851 spi1.0: eth0: revision 0, MAC 08:00:28:01:4d:c6, IRQ 194, has EEPROM
Fix this by partially reverting the original commit.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
An rmdir pushes css's ref count to zero. However, if the associated
directory is open at the time, the dentry ref count is non-zero. If
the fd for this directory is then passed into perf_event_open, it
does a css_get(). This bounces the ref count back up from zero. This
is a problem by itself. But what makes it turn into a crash is the
fact that we end up doing an extra dput, since we perform a dput
when css_put sees the ref count go down to zero.
css_tryget() does not fall into that trap. So, we use that instead.
Reproduction test-case for the bug:
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <linux/unistd.h>
#include <linux/perf_event.h>
#include <string.h>
#include <errno.h>
#include <stdio.h>
#define PERF_FLAG_PID_CGROUP (1U << 2)
int perf_event_open(struct perf_event_attr *hw_event_uptr,
pid_t pid, int cpu, int group_fd, unsigned long flags) {
return syscall(__NR_perf_event_open,hw_event_uptr, pid, cpu,
group_fd, flags);
}
/*
* Directly poke at the perf_event bug, since it's proving hard to repro
* depending on where in the kernel tree. what moved?
*/
int main(int argc, char **argv)
{
int fd;
struct perf_event_attr attr;
memset(&attr, 0, sizeof(attr));
attr.exclude_kernel = 1;
attr.size = sizeof(attr);
mkdir("/dev/cgroup/perf_event/blah", 0777);
fd = open("/dev/cgroup/perf_event/blah", O_RDONLY);
perror("open");
rmdir("/dev/cgroup/perf_event/blah");
sleep(2);
perf_event_open(&attr, fd, 0, -1, PERF_FLAG_PID_CGROUP);
perror("perf_event_open");
close(fd);
return 0;
}
Signed-off-by: Salman Qazi <sqazi@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/20120614223108.1025.2503.stgit@dungbeetle.mtv.corp.google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
