linux-toradex.git/include/linux, branch v3.3-rc7

Merge tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux-2.6

2012-03-09T01:24:27+00:00

Pull minor devicetree bug fixes and documentation updates from Grant Likely:
 "Fixes up a duplicate #include, adds an empty implementation of
  of_find_compatible_node() and make git ignore .dtb files.  And fix up
  bus name on OF described PHYs.  Nothing exciting here."

* tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux-2.6:
  doc: dt: Fix broken reference in gpio-leds documentation
  of/mdio: fix fixed link bus name
  of/fdt.c: asm/setup.h included twice
  of: add picochip vendor prefix
  dt: add empty of_find_compatible_node function
  ARM: devicetree: Add .dtb files to arch/arm/boot/.gitignore

Merge branch 'fixes' of git://git.linaro.org/people/rmk/linux-arm

2012-03-07T16:33:03+00:00

Pull ARM updates from Russell King.

* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
  ARM: 7358/1: perf: add PMU hotplug notifier
  ARM: 7357/1: perf: fix overflow handling for xscale2 PMUs
  ARM: 7356/1: perf: check that we have an event in the PMU IRQ handlers
  ARM: 7355/1: perf: clear overflow flag when disabling counter on ARMv7 PMU
  ARM: 7354/1: perf: limit sample_period to half max_period in non-sampling mode
  ARM: ecard: ensure fake vma vm_flags is setup
  ARM: 7346/1: errata: fix PL310 erratum #753970 workaround selection
  ARM: 7345/1: errata: update workaround for A9 erratum #743622
  ARM: 7348/1: arm/spear600: fix one-shot timer
  ARM: 7339/1: amba/serial.h: Include types.h for resolving dependency of type bool

Merge branch 'akpm' (Andrew's patch bomb)

2012-03-05T23:50:25+00:00

Merge the emailed seties of 19 patches from Andrew Morton

* akpm:
  rapidio/tsi721: fix queue wrapping bug in inbound doorbell handler
  memcg: fix mapcount check in move charge code for anonymous page
  mm: thp: fix BUG on mm->nr_ptes
  alpha: fix 32/64-bit bug in futex support
  memcg: fix GPF when cgroup removal races with last exit
  debugobjects: Fix selftest for static warnings
  floppy/scsi: fix setting of BIO flags
  memcg: fix deadlock by inverting lrucare nesting
  drivers/rtc/rtc-r9701.c: fix crash in r9701_remove()
  c2port: class_create() returns an ERR_PTR
  pps: class_create() returns an ERR_PTR, not NULL
  hung_task: fix the broken rcu_lock_break() logic
  vfork: kill PF_STARTING
  coredump_wait: don't call complete_vfork_done()
  vfork: make it killable
  vfork: introduce complete_vfork_done()
  aio: wake up waiters when freeing unused kiocbs
  kprobes: return proper error code from register_kprobe()
  kmsg_dump: don't run on non-error paths by default

memcg: fix GPF when cgroup removal races with last exit

2012-03-05T23:49:43+00:00

When moving tasks from old memcg (with move_charge_at_immigrate on new
memcg), followed by removal of old memcg, hit General Protection Fault in
mem_cgroup_lru_del_list() (called from release_pages called from
free_pages_and_swap_cache from tlb_flush_mmu from tlb_finish_mmu from
exit_mmap from mmput from exit_mm from do_exit).

Somewhat reproducible, takes a few hours: the old struct mem_cgroup has
been freed and poisoned by SLAB_DEBUG, but mem_cgroup_lru_del_list() is
still trying to update its stats, and take page off lru before freeing.

A task, or a charge, or a page on lru: each secures a memcg against
removal.  In this case, the last task has been moved out of the old memcg,
and it is exiting: anonymous pages are uncharged one by one from the
memcg, as they are zapped from its pagetables, so the charge gets down to
0; but the pages themselves are queued in an mmu_gather for freeing.

Most of those pages will be on lru (and force_empty is careful to
lru_add_drain_all, to add pages from pagevec to lru first), but not
necessarily all: perhaps some have been isolated for page reclaim, perhaps
some isolated for other reasons.  So, force_empty may find no task, no
charge and no page on lru, and let the removal proceed.

There would still be no problem if these pages were immediately freed; but
typically (and the put_page_testzero protocol demands it) they have to be
added back to lru before they are found freeable, then removed from lru
and freed.  We don't see the issue when adding, because the
mem_cgroup_iter() loops keep their own reference to the memcg being
scanned; but when it comes to mem_cgroup_lru_del_list().

I believe this was not an issue in v3.2: there, PageCgroupAcctLRU and
PageCgroupUsed flags were used (like a trick with mirrors) to deflect view
of pc->mem_cgroup to the stable root_mem_cgroup when neither set.
38c5d72f3ebe ("memcg: simplify LRU handling by new rule") mercifully
removed those convolutions, but left this General Protection Fault.

But it's surprisingly easy to restore the old behaviour: just check
PageCgroupUsed in mem_cgroup_lru_add_list() (which decides on which lruvec
to add), and reset pc to root_mem_cgroup if page is uncharged.  A risky
change?  just going back to how it worked before; testing, and an audit of
uses of pc->mem_cgroup, show no problem.

And there's a nice bonus: with mem_cgroup_lru_add_list() itself making
sure that an uncharged page goes to root lru, mem_cgroup_reset_owner() no
longer has any purpose, and we can safely revert 4e5f01c2b9b9 ("memcg:
clear pc->mem_cgroup if necessary").

Calling update_page_reclaim_stat() after add_page_to_lru_list() in swap.c
is not strictly necessary: the lru_lock there, with RCU before memcg
structures are freed, makes mem_cgroup_get_reclaim_stat_from_page safe
without that; but it seems cleaner to rely on one dependency less.

Signed-off-by: Hugh Dickins 
Cc: KAMEZAWA Hiroyuki 
Cc: Johannes Weiner 
Cc: Konstantin Khlebnikov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

vfork: kill PF_STARTING

2012-03-05T23:49:42+00:00

Previously it was (ab)used by utrace.  Then it was wrongly used by the
scheduler code.

Currently it is not used, kill it before it finds the new erroneous user.

Signed-off-by: Oleg Nesterov 
Acked-by: Tejun Heo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

coredump_wait: don't call complete_vfork_done()

2012-03-05T23:49:42+00:00

Now that CLONE_VFORK is killable, coredump_wait() no longer needs
complete_vfork_done().  zap_threads() should find and kill all tasks with
the same ->mm, this includes our parent if ->vfork_done is set.

mm_release() becomes the only caller, unexport complete_vfork_done().

Signed-off-by: Oleg Nesterov 
Acked-by: Tejun Heo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

vfork: make it killable

2012-03-05T23:49:42+00:00

Make vfork() killable.

Change do_fork(CLONE_VFORK) to do wait_for_completion_killable().  If it
fails we do not return to the user-mode and never touch the memory shared
with our child.

However, in this case we should clear child->vfork_done before return, we
use task_lock() in do_fork()->wait_for_vfork_done() and
complete_vfork_done() to serialize with each other.

Note: now that we use task_lock() we don't really need completion, we
could turn task->vfork_done into "task_struct *wake_up_me" but this needs
some complications.

NOTE: this and the next patches do not affect in-kernel users of
CLONE_VFORK, kernel threads run with all signals ignored including
SIGKILL/SIGSTOP.

However this is obviously the user-visible change.  Not only a fatal
signal can kill the vforking parent, a sub-thread can do execve or
exit_group() and kill the thread sleeping in vfork().

Signed-off-by: Oleg Nesterov 
Acked-by: Tejun Heo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

vfork: introduce complete_vfork_done()

2012-03-05T23:49:42+00:00

No functional changes.

Move the clear-and-complete-vfork_done code into the new trivial helper,
complete_vfork_done().

Signed-off-by: Oleg Nesterov 
Acked-by: Tejun Heo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kmsg_dump: don't run on non-error paths by default

2012-03-05T23:49:42+00:00

Since commit 04c6862c055f ("kmsg_dump: add kmsg_dump() calls to the
reboot, halt, poweroff and emergency_restart paths"), kmsg_dump() gets
run on normal paths including poweroff and reboot.

This is less than ideal given pstore implementations that can only
represent single backtraces, since a reboot may overwrite a stored oops
before it's been picked up by userspace.  In addition, some pstore
backends may have low performance and provide a significant delay in
reboot as a result.

This patch adds a printk.always_kmsg_dump kernel parameter (which can also
be changed from userspace).  Without it, the code will only be run on
failure paths rather than on normal paths.  The option can be enabled in
environments where there's a desire to attempt to audit whether or not a
reboot was cleanly requested or not.

Signed-off-by: Matthew Garrett 
Acked-by: Seiji Aguchi 
Cc: Seiji Aguchi 
Cc: David Woodhouse 
Cc: Marco Stornelli 
Cc: Artem Bityutskiy 
Cc: KOSAKI Motohiro 
Cc: Vivek Goyal 
Cc: Don Zickus 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2012-03-05T22:30:54+00:00

Pull networking fixes from David Miller:

1) TCP SACK processing can calculate an incorrect reordering value in
   some cases, fix from Neal Cardwell.

2) tcp_mark_head_lost() can split SKBs in situations where it should
   not, violating send queue invariants expected by other pieces of
   code and thus resulting (eventually) in corrupted retransmit state
   counters.  Also from Neal Cardwell.

3) qla3xxx erroneously calls spin_lock_irqrestore() with constant
   hw_flags of zero.  Fix from Santosh Nayak.

4) Fix NULL deref in rt2x00, from Gabor Juhos.

5) pch_gbe passes address of wrong typed object to pch_gbe_validate_option
   thus corrupting part of the value.  From Dan Carpenter.

6) We must check the return value of nlmsg_parse() before trying to use
   the results.  From Eric Dumazet.

7) Bridging code fails to check return value of ipv6_dev_get_saddr()
   thus potentially leaving uninitialized garbage in the outgoing ipv6
   header.  From Ulrich Weber.

8) Due to rounding and a reversed operation on jiffies, bridge message
   ages can go backwards instead of forwards, thus breaking STP.  Fixes
   from Joakim Tjernlund.

9) r8169 modifies Config* registers without properly holding the
   Config9346 lock, resulting in corrupted IP fragments on some chips.
   Fix from Francois Romieu.

10) NET_PACKET_ENGINE default wan't set properly during the network
   driver mega-move.  Fix from Stephen Hemminger.

11) vmxnet3 uses TCP header size where it actually should use the UDP
   header size, fix from Shreyas Bhatewara.

12) Netfilter bridge module autoload is busted in the compat case, fix
   from Florian Westphal.

13) Wireless Key removal was not setting multicast bits correctly thus
   accidently killing the unicast key 0 and thus all traffic stops.
   Fix from Johannes Berg.

14) Fix endless retries of A-MPDU transmissions in brcm80211 driver.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (22 commits)
  qla3xxx: ethernet: Fix bogus interrupt state flag.
  bridge: check return value of ipv6_dev_get_saddr()
  rtnetlink: fix rtnl_calcit() and rtnl_dump_ifinfo()
  bridge: message age needs to increase, not decrease.
  bridge: Adjust min age inc for HZ > 256
  tcp: don't fragment SACKed skbs in tcp_mark_head_lost()
  r8169: corrupted IP fragments fix for large mtu.
  packetengines: fix config default
  vmxnet3: Fix transport header size
  enic: fix an endian bug in enic_probe()
  pch_gbe: memory corruption calling pch_gbe_validate_option()
  tg3: Fix tg3_get_stats64 for 5700 / 5701 devs
  tcp: fix false reordering signal in tcp_shifted_skb
  tcp: fix comment for tp->highest_sack
  netfilter: bridge: fix module autoload in compat case
  brcm80211: smac: only print block-ack timeout message at trace level
  brcm80211: smac: fix endless retry of A-MPDU transmissions
  mac80211: Fix a warning on changing to monitor mode from STA
  mac80211: zero initialize count field in ieee80211_tx_rate
  iwlwifi: fix key removal
  ...