commit c69e8d9 (CRED: Use RCU to access another task's creds and to
release a task's own creds) added non rcu_read_lock() protected access
to task creds of the target task in set_prio_one().
The comment above the function says:
* - the caller must hold the RCU read lock
The calling code in sys_setpriority does read_lock(&tasklist_lock) but
not rcu_read_lock(). This works only when CONFIG_TREE_PREEMPT_RCU=n.
With CONFIG_TREE_PREEMPT_RCU=y the rcu_callbacks can run in the tick
interrupt when they see no read side critical section.
There is another instance of __task_cred() in sys_setpriority() itself
which is equally unprotected.
Wrap the whole code section into a rcu read side critical section to
fix this quick and dirty.
Will be revisited in course of the read_lock(&tasklist_lock) -> rcu
crusade.
Oleg noted further:
This also fixes another bug here. find_task_by_vpid() is not safe
without rcu_read_lock(). I do not mean it is not safe to use the
result, just find_pid_ns() by itself is not safe.
Usually tasklist gives enough protection, but if copy_process() fails
it calls free_pid() lockless and does call_rcu(delayed_put_pid().
This means, without rcu lock find_pid_ns() can't scan the hash table
safely.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <20091210004703.029784964@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
1) Remove the misleading comment in __sigqueue_alloc() which claims
that holding a spinlock is equivalent to rcu_read_lock().
2) Add a rcu_read_lock/unlock around the __task_cred() access
in __sigqueue_alloc()
This needs to be revisited to remove the remaining users of
read_lock(&tasklist_lock) but that's outside the scope of this patch.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <20091210004703.269843657@linutronix.de>
kill_pid_info_as_uid() accesses __task_cred() without being in a RCU
read side critical section. tasklist_lock is not protecting that when
CONFIG_TREE_PREEMPT_RCU=y.
Convert the whole tasklist_lock section to rcu and use
lock_task_sighand to prevent the exit race.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <20091210004703.232302055@linutronix.de>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Half the compat_ioctl handling is in devio.c, the other
half is in fs/compat_ioctl.c. This moves everything into
one place for consistency.
As a positive side-effect, push down the BKL into the
ioctl methods.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oliver@neukum.org>
Cc: Alon Bar-Lev <alon.barlev@gmail.com>
Cc: David Vrabel <david.vrabel@csr.com>
Cc: linux-usb@vger.kernel.org
Handling for LPSETTIMEOUT can easily be done in lp_ioctl, which
is the only user. As a positive side-effect, push the BKL
into the ioctl methods.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Instead of having each handler call compat_ptr, we can now
convert the pointer once and pass that to each handler.
This saves a little bit of both source and object code size.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The compat_ioctl table now only contains entries for
COMPATIBLE_IOCTL, so we only need to know if a number
is listed in it or now.
As an optimization, we hash the table entries with a
reversible transformation to get a more uniform distribution
over it, sort the table at startup and then guess the
position in the table when an ioctl number gets called
to do a linear search from there.
With the current set of ioctl numbers and the chosen
transformation function, we need an average of four
steps to find if a number is in the set, all of the
accesses within one or two cache lines.
This at least as good as the previous hash table
approach but saves 8.5 kb of kernel memory.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The compat_ioctl array now contains only entries for ioctl numbers
that do not require a separate handler. By special-casing the
ULONG_IOCTL case in the do_ioctl_trans function, we can kill the
final use of a function pointer in the array.
text data bss dec hex filename
7539 13352 2080 22971 59bb before/fs/compat_ioctl.o
7910 8552 2080 18542 486e after/fs/compat_ioctl.o
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This makes all ioctl conversion handlers called from
a single switch statement, leaving only COMPATIBLE_IOCTL
and ULONG_IOCTL statements in the table. This is somewhat
more space efficient and also lets us simplify the
handling of the lookup table significantly.
before:
text data bss dec hex filename
7619 14024 2080 23723 5cab obj/fs/compat_ioctl.o
after:
7567 13352 2080 22999 59d7 obj/fs/compat_ioctl.o
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
We have always called ioctl conversion handlers under the big kernel lock,
although that is generally not necessary. In particular it is not needed
for conversion of data structures and for calling sys_ioctl or
do_vfs_ioctl, which will get the BKL again if needed.
Handlers doing more than those two have been moved out, so we can kill off
the BKL from compat_sys_ioctl. This may significantly improve latencies
with 32 bit applications, and it avoids a common scenario where a thread
acquires the BKL twice.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The VT driver now handles all of these ioctls directly, so we can remove
the handlers from common code.
These are the only handlers that require the BKL because they directly
perform the ioctl action rather than just converting the data structures.
Once they are gone, we can remove the BKL from the remaining ioctl
conversion handlers.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
From: Randy Dunlap <randy.dunlap@oracle.com>
niu drivers uses crc32 functions, so it needs to select CRC32.
niu.c:(.text+0x18a7f8): undefined reference to `crc32_le'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Update "US" and "JP" for current rules, and replace "EU" rules with the
world roaming domain (since it was only a pseudo-domain anyway).
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Code review has shown that the generic version of
unistd.h is missing a reference to the accept4
system call. This was not noticed before because
most architectures handle this through sys_socketcall.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
After the recent commit a4177ee7f, attempting to include asm-generic/gpio.h
in otherwise "slim" code results in ugly warnings like so:
CC arch/blackfin/kernel/bfin_gpio.o
In file included from arch/blackfin/include/asm/gpio.h:278,
from arch/blackfin/kernel/bfin_gpio.c:15:
include/asm-generic/gpio.h:193: warning:
‘struct device’ declared inside parameter list
its scope is only this definition or declaration, which is probably not what you want
So add simple C forward decls of the struct device to avoid these.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The patch ("mac80211: Use correct sign for mesh active path
refresh.") was actually a bug. Reverted it and improved the
explanation of how mesh path refresh works.
Signed-off-by: Javier Cardona <javier@cozybit.com>
Signed-off-by: Andrey Yurovsky <andrey@cozybit.com>
Cc: stable@kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Paths to mesh portals were being timed out immediately after each use in
intermediate forwarding nodes. mppath->exp_time is set to the expiration time
so assigning it to jiffies was marking the path as expired.
Signed-off-by: Javier Cardona <javier@cozybit.com>
Signed-off-by: Andrey Yurovsky <andrey@cozybit.com>
Cc: stable@kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Memset should be given the size of the structure, not the size of the pointer.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@@
type T;
T *x;
expression E;
@@
memset(x, E, sizeof(
+ *
x))
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
As shown in Kernel Bugzilla #14761, doing a controller restart after a
fatal DMA error does not accomplish anything other than consume the CPU
on an affected system. Accordingly, substitute a meaningful message for
the restart.
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Stable <stable@vger.kernel.org> [2.6.32]
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Michael Buesch reports that his rtl8187 gives warnings on suspend
("queueing ieee80211 work while going to suspend" warnings), as rtl8187
can call ieee80211_queue_delayed_work after mac80211 is suspended.
This change enhances rtl8187 led code so we can avoid queuing work after
mac80211 is suspended: now we register a radio led and make additional
checks to ensure led is off/on properly as mac80211 wants.
Signed-off-by: Herton Ronaldo Krzesinski <herton@mandriva.com.br>
Tested-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Without this we have no gaurantee of the integrity of the
EEPROM and are likely to encounter a lot of bogus bug reports
due to actual issues on the EEPROM. With the EEPROM checksum
check in place we can easily rule those issues out.
If you run patch during a revert *you* have a card with a busted
EEPROM and only older kernel will support that concoction. This
patch is a trade off between not accepitng bogus EEPROMs and
avoiding bogus bug reports allowing developers to focus instead
on real concrete issues.
If stable keeps bogus bug reports because of a possibly busted EEPROM
feel free to apply this there too.
Tested on an AR5414
Cc: stable@kernel.org
Cc: jirislaby@gmail.com
Cc: akpm@linux-foundation.org
Cc: rjw@sisk.pl
Cc: me@bobcopeland.com
Cc: david.quan@atheros.com
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Port C interrupts can be either falling edge, or either edge.
Other external interrupts are either falling edge or active low.
Tested on a custom 8280 based board.
Signed-off-by: Mark Ware <mware@elphinstone.net>
Acked-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Acked-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
There are build errors when building for some of the omap2/3 boards without
enabling sound:
sound/built-in.o:(.data+0x43bc): undefined reference to `soc_codec_dev_tlv320aic23'
sound/built-in.o:(.data+0x43cc): undefined reference to `tlv320aic23_dai'
Confused me quite a bit since the drivers that had references to the
codec weren't enabled. Turns out the Makefile was using the wrong
config option to enable them. Patch below.
Reported-by: Anand Gadiyar <gadiyar@ti.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This build warning:
kernel/sched.c: In function 'set_task_cpu':
kernel/sched.c:2070: warning: unused variable 'old_rq'
Made me realize that the forced2_migrations stat looks pretty
pointless (and a misnomer) - remove it.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
I think my previous patch introduced a bug which can lead to CFQ hitting
BUG_ON().
The offending commit in for-2.6.33 branch is.
commit 7667aa0630
Author: Vivek Goyal <vgoyal@redhat.com>
Date: Tue Dec 8 17:52:58 2009 -0500
cfq-iosched: Take care of corner cases of group losing share due to deletion
While doing some stress testing on my box, I enountered following.
login: [ 3165.148841] BUG: scheduling while
atomic: swapper/0/0x10000100
[ 3165.149821] Modules linked in: cfq_iosched dm_multipath qla2xxx igb
scsi_transport_fc dm_snapshot [last unloaded: scsi_wait_scan]
[ 3165.149821] Pid: 0, comm: swapper Not tainted
2.6.32-block-for-33-merged-new #3
[ 3165.149821] Call Trace:
[ 3165.149821] <IRQ> [<ffffffff8103fab8>] __schedule_bug+0x5c/0x60
[ 3165.149821] [<ffffffff8103afd7>] ? __wake_up+0x44/0x4d
[ 3165.149821] [<ffffffff8153a979>] schedule+0xe3/0x7bc
[ 3165.149821] [<ffffffff8103a796>] ? cpumask_next+0x1d/0x1f
[ 3165.149821] [<ffffffffa000b21d>] ? cfq_dispatch_requests+0x6ba/0x93e
[cfq_iosched]
[ 3165.149821] [<ffffffff810422d8>] __cond_resched+0x2a/0x35
[ 3165.149821] [<ffffffffa000b21d>] ? cfq_dispatch_requests+0x6ba/0x93e
[cfq_iosched]
[ 3165.149821] [<ffffffff8153b1ee>] _cond_resched+0x2c/0x37
[ 3165.149821] [<ffffffff8100e2db>] is_valid_bugaddr+0x16/0x2f
[ 3165.149821] [<ffffffff811e4161>] report_bug+0x18/0xac
[ 3165.149821] [<ffffffff8100f1fc>] die+0x39/0x63
[ 3165.149821] [<ffffffff8153cde1>] do_trap+0x11a/0x129
[ 3165.149821] [<ffffffff8100d470>] do_invalid_op+0x96/0x9f
[ 3165.149821] [<ffffffffa000b21d>] ? cfq_dispatch_requests+0x6ba/0x93e
[cfq_iosched]
[ 3165.149821] [<ffffffff81034b4d>] ? enqueue_task+0x5c/0x67
[ 3165.149821] [<ffffffff8103ae83>] ? task_rq_unlock+0x11/0x13
[ 3165.149821] [<ffffffff81041aae>] ? try_to_wake_up+0x292/0x2a4
[ 3165.149821] [<ffffffff8100c935>] invalid_op+0x15/0x20
[ 3165.149821] [<ffffffffa000b21d>] ? cfq_dispatch_requests+0x6ba/0x93e
[cfq_iosched]
[ 3165.149821] [<ffffffff810df5a6>] ? virt_to_head_page+0xe/0x2f
[ 3165.149821] [<ffffffff811d8c2a>] blk_peek_request+0x191/0x1a7
[ 3165.149821] [<ffffffff811e5b8d>] ? kobject_get+0x1a/0x21
[ 3165.149821] [<ffffffff812c8d4c>] scsi_request_fn+0x82/0x3df
[ 3165.149821] [<ffffffff8110b2de>] ? bio_fs_destructor+0x15/0x17
[ 3165.149821] [<ffffffff810df5a6>] ? virt_to_head_page+0xe/0x2f
[ 3165.149821] [<ffffffff811d931f>] __blk_run_queue+0x42/0x71
[ 3165.149821] [<ffffffff811d9403>] blk_run_queue+0x26/0x3a
[ 3165.149821] [<ffffffff812c8761>] scsi_run_queue+0x2de/0x375
[ 3165.149821] [<ffffffff812b60ac>] ? put_device+0x17/0x19
[ 3165.149821] [<ffffffff812c92d7>] scsi_next_command+0x3b/0x4b
[ 3165.149821] [<ffffffff812c9b9f>] scsi_io_completion+0x1c9/0x3f5
[ 3165.149821] [<ffffffff812c3c36>] scsi_finish_command+0xb5/0xbe
I think I have hit following BUG_ON() in cfq_dispatch_request().
BUG_ON(RB_EMPTY_ROOT(&cfqq->sort_list));
Please find attached the patch to fix it. I have done some stress testing
with it and have not seen it happening again.
o We should wait on a queue even after slice expiry only if it is empty. If
queue is not empty then continue to expire it.
o If we decide to keep the queue then make cfqq=NULL. Otherwise select_queue()
will return a valid cfqq and cfq_dispatch_request() can hit following
BUG_ON().
BUG_ON(RB_EMPTY_ROOT(&cfqq->sort_list))
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Add missing include for msm_sdcc compilation, and remove pwrsink
support that is not mainline, yet.
Signed-off-by: Pavel Machek <pavel@ucw.cz>
[dwalker@codeaurora.org : fixed indent in mmc.h]
Signed-off-by: Daniel Walker <dwalker@codeaurora.org>
Allow user to select MSM framebuffer support in Kconfig.
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Daniel Walker <dwalker@codeaurora.org>
This adds a maintainer entry for the arch/arm/mach-msm sub-architecture and
all it's components in various locations.
Signed-off-by: David Brown <davidb@codeaurora.org>
Signed-off-by: Bryan Huntsman <bryanh@codeaurora.org>
Signed-off-by: Daniel Walker <dwalker@codeaurora.org>
* 'bugfix' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
xen: try harder to balloon up under memory pressure.
Xen balloon: fix totalram_pages counting.
xen: explicitly create/destroy stop_machine workqueues outside suspend/resume region.
xen: improve error handling in do_suspend.
xen: don't leak IRQs over suspend/resume.
xen: call clock resume notifier on all CPUs
xen: use iret for return from 64b kernel to 32b usermode
xen: don't call dpm_resume_noirq() with interrupts disabled.
xen: register runstate info for boot CPU early
xen: register runstate on secondary CPUs
xen: register timer interrupt with IRQF_TIMER
xen: correctly restore pfn_to_mfn_list_list after resume
xen: restore runstate_info even if !have_vcpu_info_placement
xen: re-register runstate area earlier on resume.
xen: wait up to 5 minutes for device connetion
xen: improvement to wait_for_devices()
xen: fix is_disconnected_device/exists_disconnected_device
xen/xenbus: make DEVICE_ATTR()s static
* 'xen/fbdev' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
xen pvfb: Inhibit VM_IO flag to be set on vmalloc-ed framebuffers.
fb-defio: Inhibit VM_IO flag to be set on vmalloc-ed framebuffers.
fb-defio: If FBINFO_VIRTFB is defined, do not set VM_IO flag.
Fix toogle whether xenbus driver should be built as module or part of kernel.
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (47 commits)
ext4: Fix potential fiemap deadlock (mmap_sem vs. i_data_sem)
ext4: Do not override ext2 or ext3 if built they are built as modules
jbd2: Export jbd2_log_start_commit to fix ext4 build
ext4: Fix insufficient checks in EXT4_IOC_MOVE_EXT
ext4: Wait for proper transaction commit on fsync
ext4: fix incorrect block reservation on quota transfer.
ext4: quota macros cleanup
ext4: ext4_get_reserved_space() must return bytes instead of blocks
ext4: remove blocks from inode prealloc list on failure
ext4: wait for log to commit when umounting
ext4: Avoid data / filesystem corruption when write fails to copy data
ext4: Use ext4 file system driver for ext2/ext3 file system mounts
ext4: Return the PTR_ERR of the correct pointer in setup_new_group_blocks()
jbd2: Add ENOMEM checking in and for jbd2_journal_write_metadata_buffer()
ext4: remove unused parameter wbc from __ext4_journalled_writepage()
ext4: remove encountered_congestion trace
ext4: move_extent_per_page() cleanup
ext4: initialize moved_len before calling ext4_move_extents()
ext4: Fix double-free of blocks with EXT4_IOC_MOVE_EXT
ext4: use ext4_data_block_valid() in ext4_free_blocks()
...
* 'for-linus' of git://git.open-osd.org/linux-open-osd:
exofs: Multi-device mirror support
exofs: Move all operations to an io_engine
exofs: move osd.c to ios.c
exofs: statfs blocks is sectors not FS blocks
exofs: Prints on mount and unmout
exofs: refactor exofs_i_info initialization into common helper
exofs: dbg-print less
exofs: More sane debug print
trivial: some small fixes in exofs documentation
Add more data to printk's, add some spaces around arithmetic ops and
improve comments.
Signed-off-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Enhance error handle for IO patch, when the port is down, fast return phy
down for task.
Signed-off-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This patch fix for sata IO circular lock dependency. When we call task_done
for SATA IO, we have got pm8001_ha->lock ,and in sas_ata_task_done, it will
get (dev->sata_dev.ap->lock. then cause circular lock dependency .So we
should drop pm8001_ha->lock when we call task_done for SATA task.
Signed-off-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: Lindar Liu <lindar_liu@usish.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This driver supports a subset of HP Smart Array Controllers.
It is a SCSI alternative to the cciss driver.
[akpm@linux-foundation.org: avoid helpful cleanup patches]
[achiang@hp.com: make device attrs static]
[akpm@linux-foundation.org: msleep() does set_current_state() itself]
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Mike Miller <mikem@beardog.cce.hp.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Removed duplicate function call and not-so-useful comment line
Signed-off-by: Anil Veerabhadrappa <anilgv@broadcom.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
