linux-toradex.git, branch v3.11.6

Linux 3.11.6

2013-10-18T18:24:16+00:00

x86: avoid remapping data in parse_setup_data()

2013-10-18T17:55:02+00:00

commit 30e46b574a1db7d14404e52dca8e1aa5f5155fd2 upstream.

Type SETUP_PCI, added by setup_efi_pci(), may advertise a ROM size
larger than early_memremap() is able to handle, which is currently
limited to 256kB. If this occurs it leads to a NULL dereference in
parse_setup_data().

To avoid this, remap the setup_data header and allow parsing functions
for individual types to handle their own data remapping.

Signed-off-by: Linn Crosetto 
Link: http://lkml.kernel.org/r/1376430401-67445-1-git-send-email-linn@hp.com
Acked-by: Yinghai Lu 
Reviewed-by: Pekka Enberg 
Signed-off-by: H. Peter Anvin 
Cc: Paul Gortmaker 
Signed-off-by: Greg Kroah-Hartman

ipc/sem.c: update sem_otime for all operations

2013-10-18T17:55:02+00:00

commit 0e8c665699e953fa58dc1b0b0d09e5dce7343cc7 upstream.

In commit 0a2b9d4c7967 ("ipc/sem.c: move wake_up_process out of the
spinlock section"), the update of semaphore's sem_otime(last semop time)
was moved to one central position (do_smart_update).

But since do_smart_update() is only called for operations that modify
the array, this means that wait-for-zero semops do not update sem_otime
anymore.

The fix is simple:
Non-alter operations must update sem_otime.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Manfred Spraul 
Reported-by: Jia He 
Tested-by: Jia He 
Cc: Davidlohr Bueso 
Cc: Mike Galbraith 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ipc/sem.c: synchronize the proc interface

2013-10-18T17:55:02+00:00

commit d8c633766ad88527f25d9f81a5c2f083d78a2b39 upstream.

The proc interface is not aware of sem_lock(), it instead calls
ipc_lock_object() directly.  This means that simple semop() operations
can run in parallel with the proc interface.  Right now, this is
uncritical, because the implementation doesn't do anything that requires
a proper synchronization.

But it is dangerous and therefore should be fixed.

Signed-off-by: Manfred Spraul 
Cc: Davidlohr Bueso 
Cc: Mike Galbraith 
Cc: Rik van Riel 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ipc/sem.c: optimize sem_lock()

2013-10-18T17:55:02+00:00

commit 6d07b68ce16ae9535955ba2059dedba5309c3ca1 upstream.

Operations that need access to the whole array must guarantee that there
are no simple operations ongoing.  Right now this is achieved by
spin_unlock_wait(sem->lock) on all semaphores.

If complex_count is nonzero, then this spin_unlock_wait() is not
necessary, because it was already performed in the past by the thread
that increased complex_count and even though sem_perm.lock was dropped
inbetween, no simple operation could have started, because simple
operations cannot start when complex_count is non-zero.

Signed-off-by: Manfred Spraul 
Cc: Mike Galbraith 
Cc: Rik van Riel 
Reviewed-by: Davidlohr Bueso 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Cc: Mike Galbraith 
Signed-off-by: Greg Kroah-Hartman

ipc: drop ipc_lock_check

2013-10-18T17:55:02+00:00

commit 20b8875abcf2daa1dda5cf70bd6369df5e85d4c1 upstream.

No remaining users, we now use ipc_obtain_object_check().

Signed-off-by: Davidlohr Bueso 
Cc: Sedat Dilek 
Cc: Rik van Riel 
Cc: Manfred Spraul 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Cc: Mike Galbraith 
Signed-off-by: Greg Kroah-Hartman

ipc, shm: drop shm_lock_check

2013-10-18T17:55:01+00:00

commit 7a25dd9e042b2b94202a67e5551112f4ac87285a upstream.

This function was replaced by a the lockless shm_obtain_object_check(),
and no longer has any users.

Signed-off-by: Davidlohr Bueso 
Cc: Sedat Dilek 
Cc: Rik van Riel 
Cc: Manfred Spraul 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Cc: Mike Galbraith 
Signed-off-by: Greg Kroah-Hartman

ipc: drop ipc_lock_by_ptr

2013-10-18T17:55:01+00:00

commit 32a2750010981216fb788c5190fb0e646abfab30 upstream.

After previous cleanups and optimizations, this function is no longer
heavily used and we don't have a good reason to keep it.  Update the few
remaining callers and get rid of it.

Signed-off-by: Davidlohr Bueso 
Cc: Sedat Dilek 
Cc: Rik van Riel 
Cc: Manfred Spraul 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Cc: Mike Galbraith 
Signed-off-by: Greg Kroah-Hartman

ipc, shm: guard against non-existant vma in shmdt(2)

2013-10-18T17:55:01+00:00

commit 530fcd16d87cd2417c472a581ba5a1e501556c86 upstream.

When !CONFIG_MMU there's a chance we can derefence a NULL pointer when the
VM area isn't found - check the return value of find_vma().

Also, remove the redundant -EINVAL return: retval is set to the proper
return code and *only* changed to 0, when we actually unmap the segments.

Signed-off-by: Davidlohr Bueso 
Cc: Sedat Dilek 
Cc: Rik van Riel 
Cc: Manfred Spraul 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Cc: Mike Galbraith 
Signed-off-by: Greg Kroah-Hartman

ipc: document general ipc locking scheme

2013-10-18T17:55:01+00:00

commit 05603c44a7627793219b0bd9a7b236099dc9cd9d upstream.

As suggested by Andrew, add a generic initial locking scheme used
throughout all sysv ipc mechanisms.  Documenting the ids rwsem, how rcu
can be enough to do the initial checks and when to actually acquire the
kern_ipc_perm.lock spinlock.

I found that adding it to util.c was generic enough.

Signed-off-by: Davidlohr Bueso 
Tested-by: Sedat Dilek 
Cc: Rik van Riel 
Cc: Manfred Spraul 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Cc: Mike Galbraith 
Signed-off-by: Greg Kroah-Hartman