linux-stable.git/fs/pstore, branch v3.9

Merge tag 'please-pull-pstore' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux

2013-02-21T17:38:18+00:00

Pull pstore patches from Tony Luck:
 "A few fixes to reduce places where pstore might hang a system in the
  crash path.  Plus a new mountpoint (/sys/fs/pstore ...  makes more
  sense then /dev/pstore)."

Fix up trivial conflict in drivers/firmware/efivars.c

* tag 'please-pull-pstore' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux:
  pstore: Create a convenient mount point for pstore
  efi_pstore: Introducing workqueue updating sysfs
  efivars: Disable external interrupt while holding efivars->lock
  efi_pstore: Avoid deadlock in non-blocking paths
  pstore: Avoid deadlock in panic and emergency-restart path

pstore: Create a convenient mount point for pstore

2013-02-12T21:07:22+00:00

Using /dev/pstore as a mount point for the pstore filesystem is slightly
awkward.  We don't normally mount filesystems in /dev/ and the /dev/pstore
file isn't created automatically by anything.  While this method will
still work, we can create a persistent mount point in sysfs.  This will
put pstore on par with things like cgroups and efivarfs.

Signed-off-by: Josh Boyer 
Acked-by: Kees Cook 
Signed-off-by: Tony Luck

Merge branch 'fortglx/3.9/time' of git://git.linaro.org/people/jstultz/linux into timers/core

2013-02-04T10:03:03+00:00

Trivial conflict in arch/x86/Kconfig

Signed-off-by: Thomas Gleixner

time: create __getnstimeofday for WARNless calls

2013-01-16T02:16:02+00:00

The pstore RAM backend can get called during resume, and must be defensive
against a suspended time source. Expose getnstimeofday logic that returns
an error instead of a WARN. This can be detected and the timestamp can
be zeroed out.

Reported-by: Doug Anderson 
Cc: John Stultz 
Cc: Anton Vorontsov 
Signed-off-by: Kees Cook 
Signed-off-by: John Stultz

pstore: Avoid deadlock in panic and emergency-restart path

2013-01-11T18:20:50+00:00

[Issue]

When pstore is in panic and emergency-restart paths, it may be blocked
in those paths because it simply takes spin_lock.

This is an example scenario which pstore may hang up in a panic path:

 - cpuA grabs psinfo->buf_lock
 - cpuB panics and calls smp_send_stop
 - smp_send_stop sends IRQ to cpuA
 - after 1 second, cpuB gives up on cpuA and sends an NMI instead
 - cpuA is now in an NMI handler while still holding buf_lock
 - cpuB is deadlocked

This case may happen if a firmware has a bug and
cpuA is stuck talking with it more than one second.

Also, this is a similar scenario in an emergency-restart path:

 - cpuA grabs psinfo->buf_lock and stucks in a firmware
 - cpuB kicks emergency-restart via either sysrq-b or hangcheck timer.
   And then, cpuB is deadlocked by taking psinfo->buf_lock again.

[Solution]

This patch avoids the deadlocking issues in both panic and emergency_restart
paths by introducing a function, is_non_blocking_path(), to check if a cpu
can be blocked in current path.

With this patch, pstore is not blocked even if another cpu has
taken a spin_lock, in those paths by changing from spin_lock_irqsave
to spin_trylock_irqsave.

In addition, according to a comment of emergency_restart() in kernel/sys.c,
spin_lock shouldn't be taken in an emergency_restart path to avoid
deadlock. This patch fits the comment below.


/**
 *      emergency_restart - reboot the system
 *
 *      Without shutting down any hardware or taking any locks
 *      reboot the system.  This is called when we know we are in
 *      trouble so this is our best effort to reboot.  This is
 *      safe to call in interrupt context.
 */
void emergency_restart(void)


Signed-off-by: Seiji Aguchi 
Acked-by: Don Zickus 
Signed-off-by: Tony Luck

pstore: remove __dev* attributes.

2013-01-03T23:57:14+00:00

CONFIG_HOTPLUG is going away as an option.  As a result, the __dev*
markings need to be removed.

This change removes the use of __devinit from the pstore filesystem.

Based on patches originally written by Bill Pemberton, but redone by me
in order to handle some of the coding style issues better, by hand.

Cc: Bill Pemberton 
Cc: Anton Vorontsov 
Cc: Colin Cross 
Cc: Kees Cook 
Cc: Tony Luck 
Signed-off-by: Greg Kroah-Hartman

lseek: the "whence" argument is called "whence"

2012-12-18T01:15:12+00:00

But the kernel decided to call it "origin" instead.  Fix most of the
sites.

Acked-by: Hugh Dickins 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge tag 'for-v3.8' of git://git.infradead.org/users/cbou/linux-pstore

2012-12-15T20:51:50+00:00

Pull pstore update from Anton Vorontsov:
 "Here are just a few fixups for the pstore subsystem, nothing special
  this time"

* tag 'for-v3.8' of git://git.infradead.org/users/cbou/linux-pstore:
  pstore/ftrace: Adjust for ftrace_ops->func prototype change
  pstore/ram: Fix bounds checks for mem_size, record_size, console_size and ftrace_size
  pstore/ram: Fix undefined usage of rounddown_pow_of_two(0)
  pstore/ram: Fixup section annotations

pstore/ftrace: Adjust for ftrace_ops->func prototype change

2012-12-13T03:50:04+00:00

This commit fixes the following warning:

 fs/pstore/ftrace.c:51:2: warning: initialization from incompatible
 pointer type [enabled by default]
 fs/pstore/ftrace.c:51:2: warning: (near initialization for
 ‘pstore_ftrace_ops.func’) [enabled by defaula

Signed-off-by: Anton Vorontsov

pstore/ram: Fix bounds checks for mem_size, record_size, console_size and ftrace_size

2012-12-13T03:02:52+00:00

The bounds check in ramoops_init_prz was incorrect and ramoops_init_przs
had no check. Additionally, ramoops_init_przs allows record_size to be 0,
but ramoops_pstore_write_buf would always crash in this case.

Signed-off-by: Arve Hjønnevåg 
Signed-off-by: Anton Vorontsov