Commit Graph

400179 Commits

Author SHA1 Message Date
Dave Jones 7a20c2fad6 x86/reboot: Fix apparent cut-n-paste mistake in Dell reboot workaround
This seems to have been copied from the Optiplex 990 entry
above, but somoene forgot to change the ident text.

Signed-off-by: Dave Jones <davej@fedoraproject.org>
Link: http://lkml.kernel.org/r/20130925001344.GA13554@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-25 08:41:10 +02:00
Benjamin Herrenschmidt dbe78b4011 powerpc/pseries: Do not start secondaries in Open Firmware
Starting secondary CPUs early on from Open Firmware and placing them
in a holding spin loop slows down the boot process significantly under
some hypervisors such as KVM.

This is also unnecessary when RTAS supports querying the CPU state

So let's not do it.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-09-25 14:19:00 +10:00
Benjamin Herrenschmidt 0c9fa29149 powerpc/zImage: make the "OF" wrapper support ePAPR boot
This makes the "OF" zImage wrapper (zImage.pseries, zImage.pmac,
zImage.maple) work if booted via a flat device-tree (ePAPR boot
mode), and thus potentially usable with kexec.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-09-25 14:18:44 +10:00
Benjamin Herrenschmidt cbc9565ee8 powerpc: Remove ksp_limit on ppc64
We've been keeping that field in thread_struct for a while, it contains
the "limit" of the current stack pointer and is meant to be used for
detecting stack overflows.

It has a few problems however:

 - First, it was never actually *used* on 64-bit. Set and updated but
not actually exploited

 - When switching stack to/from irq and softirq stacks, it's update
is racy unless we hard disable interrupts, which is costly. This
is fine on 32-bit as we don't soft-disable there but not on 64-bit.

Thus rather than fixing 2 in order to implement 1 in some hypothetical
future, let's remove the code completely from 64-bit. In order to avoid
a clutter of ifdef's, we remove the updates from C code completely
during interrupt stack switching, and instead maintain it from the
asm helper that is used to do the stack switching in the first place.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-09-25 14:15:51 +10:00
Benjamin Herrenschmidt 0366a1c70b powerpc/irq: Run softirqs off the top of the irq stack
Nowadays, irq_exit() calls __do_softirq() pretty much directly
instead of calling do_softirq() which switches to the decicated
softirq stack.

This has lead to observed stack overflows on powerpc since we call
irq_enter() and irq_exit() outside of the scope that switches to
the irq stack.

This fixes it by moving the stack switching up a level, making
irq_enter() and irq_exit() run off the irq stack.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-09-25 14:15:36 +10:00
Paul E. McKenney 22356f447c mm: Place preemption point in do_mlockall() loop
There is a loop in do_mlockall() that lacks a preemption point, which
means that the following can happen on non-preemptible builds of the
kernel. Dave Jones reports:

 "My fuzz tester keeps hitting this.  Every instance shows the non-irq
  stack came in from mlockall.  I'm only seeing this on one box, but
  that has more ram (8gb) than my other machines, which might explain
  it.

    INFO: rcu_preempt self-detected stall on CPU { 3}  (t=6500 jiffies g=470344 c=470343 q=0)
    sending NMI to all CPUs:
    NMI backtrace for cpu 3
    CPU: 3 PID: 29664 Comm: trinity-child2 Not tainted 3.11.0-rc1+ #32
    Call Trace:
      lru_add_drain_all+0x15/0x20
      SyS_mlockall+0xa5/0x1a0
      tracesys+0xdd/0xe2"

This commit addresses this problem by inserting the required preemption
point.

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 19:44:40 -07:00
Dinh Nguyen 53126a2f67 dts: Fix misspelling of Synopsys
s/Synopsis/Synopsys
s/synopsis/synopsys

Signed-off-by: Dinh Nguyen <dinguyen@altera.com>
Cc: Pavel Machek <pavel@denx.de>
CC: Arnd Bergmann <arnd@arndb.de>
CC: Olof Johansson <olof@lixom.net>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Chris Ball <cjb@laptop.org>
Cc: Jaehoon Chung <jh80.chung@samsung.com>
Cc: Seungwon Jeon <tgih.jun@samsung.com>
Cc: Tomasz Figa <tomasz.figa@gmail.com>
Cc: devicetree@vger.kernel.org
Cc: linux-mmc@vger.kernel.org
CC: linux-arm-kernel@lists.infradead.org
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2013-09-24 21:13:38 -05:00
Rob Herring b0b8c960ff of: clean-up ifdefs in of_irq.h
Much of of_irq.h is needlessly ifdef'ed. Clean this up and minimize the
amount ifdef'ed code. This fixes some  build warnings when CONFIG_OF
is not enabled (seen on i386 and x86_64):

include/linux/of_irq.h:82:7: warning: 'struct device_node' declared inside parameter list [enabled by default]
include/linux/of_irq.h:82:7: warning: its scope is only this definition or declaration, which is probably not what you want [enabled by default]
include/linux/of_irq.h:87:47: warning: 'struct device_node' declared inside parameter list [enabled by default]

Compile tested on i386, sparc and arm.

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2013-09-24 21:12:32 -05:00
Rob Herring ede2033c40 openrisc: clean-up prom.h
Clean-up some copy/paste declarations that are not necessary. All the
functions either don't exist or are already declared in other headers.
This is needed in preparation of of_irq.h clean-up.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: linux@lists.openrisc.net
2013-09-24 21:12:27 -05:00
Sachin Kamat 116decb7e4 cpufreq: exynos5440: Fix potential NULL pointer dereference
If 'dvfs_info' is NULL (due to devm_kzalloc failure) the failure
error message would try to dereference it. Use 'pdev' instead.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-25 03:25:58 +02:00
Viresh Kumar 26ca869434 cpufreq: check cpufreq driver is valid and cpufreq isn't disabled in cpufreq_get()
cpufreq_get() can be called from external drivers which might not be aware if
cpufreq driver is registered or not. And so we should actually check if cpufreq
driver is registered or not and also if cpufreq is active or disabled, at the
beginning of cpufreq_get().

Otherwise call to lock_policy_rwsem_read() might hit BUG_ON(!policy).

Reported-and-tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-25 03:24:02 +02:00
Yinghai Lu 8a61e12e84 acpi-cpufreq: skip loading acpi_cpufreq after intel_pstate
If the hw supports intel_pstate and acpi_cpufreq, intel_pstate will
get loaded first.

acpi_cpufreq_init() will call acpi_cpufreq_early_init()
and that will allocate perf data and init those perf data in ACPI core,
(that will cover all CPUs). But later it will free them as
cpufreq_register_driver(acpi_cpufreq) will fail as intel_pstate is
already registered

Use cpufreq_get_current_driver() to check if we can skip the
acpi_cpufreq loading.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-25 03:19:09 +02:00
Lv Zheng 06a8566bcf ACPI / IPMI: Fix atomic context requirement of ipmi_msg_handler()
This patch fixes the issues indicated by the test results that
ipmi_msg_handler() is invoked in atomic context.

BUG: scheduling while atomic: kipmi0/18933/0x10000100
Modules linked in: ipmi_si acpi_ipmi ...
CPU: 3 PID: 18933 Comm: kipmi0 Tainted: G       AW    3.10.0-rc7+ #2
Hardware name: QCI QSSC-S4R/QSSC-S4R, BIOS QSSC-S4R.QCI.01.00.0027.070120100606 07/01/2010
 ffff8838245eea00 ffff88103fc63c98 ffffffff814c4a1e ffff88103fc63ca8
 ffffffff814bfbab ffff88103fc63d28 ffffffff814c73e0 ffff88103933cbd4
 0000000000000096 ffff88103fc63ce8 ffff88102f618000 ffff881035c01fd8
Call Trace:
 <IRQ>  [<ffffffff814c4a1e>] dump_stack+0x19/0x1b
 [<ffffffff814bfbab>] __schedule_bug+0x46/0x54
 [<ffffffff814c73e0>] __schedule+0x83/0x59c
 [<ffffffff81058853>] __cond_resched+0x22/0x2d
 [<ffffffff814c794b>] _cond_resched+0x14/0x1d
 [<ffffffff814c6d82>] mutex_lock+0x11/0x32
 [<ffffffff8101e1e9>] ? __default_send_IPI_dest_field.constprop.0+0x53/0x58
 [<ffffffffa09e3f9c>] ipmi_msg_handler+0x23/0x166 [ipmi_si]
 [<ffffffff812bf6e4>] deliver_response+0x55/0x5a
 [<ffffffff812c0fd4>] handle_new_recv_msgs+0xb67/0xc65
 [<ffffffff81007ad1>] ? read_tsc+0x9/0x19
 [<ffffffff814c8620>] ? _raw_spin_lock_irq+0xa/0xc
 [<ffffffffa09e1128>] ipmi_thread+0x5c/0x146 [ipmi_si]
 ...

Also Tony Camuso says:

 We were getting occasional "Scheduling while atomic" call traces
 during boot on some systems. Problem was first seen on a Cisco C210
 but we were able to reproduce it on a Cisco c220m3. Setting
 CONFIG_LOCKDEP and LOCKDEP_SUPPORT to 'y' exposed a lockdep around
 tx_msg_lock in acpi_ipmi.c struct acpi_ipmi_device.

 =================================
 [ INFO: inconsistent lock state ]
 2.6.32-415.el6.x86_64-debug-splck #1
 ---------------------------------
 inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
 ksoftirqd/3/17 [HC0[0]:SC1[1]:HE1:SE0] takes:
  (&ipmi_device->tx_msg_lock){+.?...}, at: [<ffffffff81337a27>] ipmi_msg_handler+0x71/0x126
 {SOFTIRQ-ON-W} state was registered at:
   [<ffffffff810ba11c>] __lock_acquire+0x63c/0x1570
   [<ffffffff810bb0f4>] lock_acquire+0xa4/0x120
   [<ffffffff815581cc>] __mutex_lock_common+0x4c/0x400
   [<ffffffff815586ea>] mutex_lock_nested+0x4a/0x60
   [<ffffffff8133789d>] acpi_ipmi_space_handler+0x11b/0x234
   [<ffffffff81321c62>] acpi_ev_address_space_dispatch+0x170/0x1be

The fix implemented by this change has been tested by Tony:

 Tested the patch in a boot loop with lockdep debug enabled and never
 saw the problem in over 400 reboots.

Reported-and-tested-by: Tony Camuso <tcamuso@redhat.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Reviewed-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-25 03:12:05 +02:00
Linus Torvalds a153e67bda Merge branch 'akpm' (patches from Andrew Morton)
Merge fixes from Andrew Morton:
 "Bunch of fixes.

  And a reversion of mhocko's "Soft limit rework" patch series.  This is
  actually your fault for opening the merge window when I was off racing ;)

  I didn't read the email thread before sending everything off.
  Johannes Weiner raised significant issues:

    http://www.spinics.net/lists/cgroups/msg08813.html

  and we agreed to back it all out"

I clearly need to be more aware of Andrew's racing schedule.

* akpm:
  MAINTAINERS: update mach-bcm related email address
  checkpatch: make extern in .h prototypes quieter
  cciss: fix info leak in cciss_ioctl32_passthru()
  cpqarray: fix info leak in ida_locked_ioctl()
  kernel/reboot.c: re-enable the function of variable reboot_default
  audit: fix endless wait in audit_log_start()
  revert "memcg, vmscan: integrate soft reclaim tighter with zone shrinking code"
  revert "memcg: get rid of soft-limit tree infrastructure"
  revert "vmscan, memcg: do softlimit reclaim also for targeted reclaim"
  revert "memcg: enhance memcg iterator to support predicates"
  revert "memcg: track children in soft limit excess to improve soft limit"
  revert "memcg, vmscan: do not attempt soft limit reclaim if it would not scan anything"
  revert "memcg: track all children over limit in the root"
  revert "memcg, vmscan: do not fall into reclaim-all pass too quickly"
  fs/ocfs2/super.c: use a bigger nodestr in ocfs2_dismount_volume
  watchdog: update watchdog_thresh properly
  watchdog: update watchdog attributes atomically
2013-09-24 17:00:35 -07:00
Christian Daudt 497a045d13 MAINTAINERS: update mach-bcm related email address
Update email address on mach-bcm + drivers for Broadcom mobile SoCs.

Signed-off-by: Christian Daudt <csd@broadcom.com>
Cc: Olof Johansson <olof@lixom.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:26 -07:00
Joe Perches d1d85780dd checkpatch: make extern in .h prototypes quieter
The use of extern in .h files is a bit contentious.

Make the warning be emitted only when --strict is used on the command
line.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:26 -07:00
Dan Carpenter 58f09e00ae cciss: fix info leak in cciss_ioctl32_passthru()
The arg64 struct has a hole after ->buf_size which isn't cleared.  Or if
any of the calls to copy_from_user() fail then that would cause an
information leak as well.

This was assigned CVE-2013-2147.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Mike Miller <mike.miller@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:26 -07:00
Dan Carpenter 627aad1c01 cpqarray: fix info leak in ida_locked_ioctl()
The pciinfo struct has a two byte hole after ->dev_fn so stack
information could be leaked to the user.

This was assigned CVE-2013-2147.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Mike Miller <mike.miller@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:26 -07:00
Chuansheng Liu e2f0b88e84 kernel/reboot.c: re-enable the function of variable reboot_default
Commit 1b3a5d02ee ("reboot: move arch/x86 reboot= handling to generic
kernel") did some cleanup for reboot= command line, but it made the
reboot_default inoperative.

The default value of variable reboot_default should be 1, and if command
line reboot= is not set, system will use the default reboot mode.

[akpm@linux-foundation.org: fix comment layout]
Signed-off-by: Li Fei <fei.li@intel.com>
Signed-off-by: liu chuansheng <chuansheng.liu@intel.com>
Acked-by: Robin Holt <robinmholt@linux.com>
Cc: <stable@vger.kernel.org>	[3.11.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:26 -07:00
Konstantin Khlebnikov 8ac1c8d5de audit: fix endless wait in audit_log_start()
After commit 829199197a ("kernel/audit.c: avoid negative sleep
durations") audit emitters will block forever if userspace daemon cannot
handle backlog.

After the timeout the waiting loop turns into busy loop and runs until
daemon dies or returns back to work.  This is a minimal patch for that
bug.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Richard Guy Briggs <rgb@redhat.com>
Cc: Eric Paris <eparis@redhat.com>
Cc: Chuck Anderson <chuck.anderson@oracle.com>
Cc: Dan Duval <dan.duval@oracle.com>
Cc: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:26 -07:00
Andrew Morton 0608f43da6 revert "memcg, vmscan: integrate soft reclaim tighter with zone shrinking code"
Revert commit 3b38722efd ("memcg, vmscan: integrate soft reclaim
tighter with zone shrinking code")

I merged this prematurely - Michal and Johannes still disagree about the
overall design direction and the future remains unclear.

Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:26 -07:00
Andrew Morton bb4cc1a8b5 revert "memcg: get rid of soft-limit tree infrastructure"
Revert commit e883110aad ("memcg: get rid of soft-limit tree
infrastructure")

I merged this prematurely - Michal and Johannes still disagree about the
overall design direction and the future remains unclear.

Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:26 -07:00
Andrew Morton b1aff7fcf8 revert "vmscan, memcg: do softlimit reclaim also for targeted reclaim"
Revert commit a5b7c87f92 ("vmscan, memcg: do softlimit reclaim also
for targeted reclaim")

I merged this prematurely - Michal and Johannes still disagree about the
overall design direction and the future remains unclear.

Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:26 -07:00
Andrew Morton 694fbc0fe7 revert "memcg: enhance memcg iterator to support predicates"
Revert commit de57780dc6 ("memcg: enhance memcg iterator to support
predicates")

I merged this prematurely - Michal and Johannes still disagree about the
overall design direction and the future remains unclear.

Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:26 -07:00
Andrew Morton 30361e51ca revert "memcg: track children in soft limit excess to improve soft limit"
Revert commit 7d910c054b ("memcg: track children in soft limit excess
to improve soft limit")

I merged this prematurely - Michal and Johannes still disagree about the
overall design direction and the future remains unclear.

Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:25 -07:00
Andrew Morton 3120055e86 revert "memcg, vmscan: do not attempt soft limit reclaim if it would not scan anything"
Revert commit e839b6a1c8 ("memcg, vmscan: do not attempt soft limit
reclaim if it would not scan anything")

I merged this prematurely - Michal and Johannes still disagree about the
overall design direction and the future remains unclear.

Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:25 -07:00
Andrew Morton 8f939a9f4c revert "memcg: track all children over limit in the root"
Revert commit 1be171d60b ("memcg: track all children over limit in the
root")

I merged this prematurely - Michal and Johannes still disagree about the
overall design direction and the future remains unclear.

Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:25 -07:00
Andrew Morton 20ba27f52e revert "memcg, vmscan: do not fall into reclaim-all pass too quickly"
Revert commit e975de998b ("memcg, vmscan: do not fall into reclaim-all
pass too quickly")

I merged this prematurely - Michal and Johannes still disagree about the
overall design direction and the future remains unclear.

Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:25 -07:00
Goldwyn Rodrigues 99d7a8824a fs/ocfs2/super.c: use a bigger nodestr in ocfs2_dismount_volume
While printing 32-bit node numbers, an 8-byte string is not enough.
Increase the size of the string to 12 chars.

This got left out in commit 49fa8140e4 ("fs/ocfs2/super.c: Use bigger
nodestr to accomodate 32-bit node numbers").

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:25 -07:00
Michal Hocko 9809b18fcf watchdog: update watchdog_thresh properly
watchdog_tresh controls how often nmi perf event counter checks per-cpu
hrtimer_interrupts counter and blows up if the counter hasn't changed
since the last check.  The counter is updated by per-cpu
watchdog_hrtimer hrtimer which is scheduled with 2/5 watchdog_thresh
period which guarantees that hrtimer is scheduled 2 times per the main
period.  Both hrtimer and perf event are started together when the
watchdog is enabled.

So far so good.  But...

But what happens when watchdog_thresh is updated from sysctl handler?

proc_dowatchdog will set a new sampling period and hrtimer callback
(watchdog_timer_fn) will use the new value in the next round.  The
problem, however, is that nobody tells the perf event that the sampling
period has changed so it is ticking with the period configured when it
has been set up.

This might result in an ear ripping dissonance between perf and hrtimer
parts if the watchdog_thresh is increased.  And even worse it might lead
to KABOOM if the watchdog is configured to panic on such a spurious
lockup.

This patch fixes the issue by updating both nmi perf even counter and
hrtimers if the threshold value has changed.

The nmi one is disabled and then reinitialized from scratch.  This has
an unpleasant side effect that the allocation of the new event might
fail theoretically so the hard lockup detector would be disabled for
such cpus.  On the other hand such a memory allocation failure is very
unlikely because the original event is deallocated right before.

It would be much nicer if we just changed perf event period but there
doesn't seem to be any API to do that right now.  It is also unfortunate
that perf_event_alloc uses GFP_KERNEL allocation unconditionally so we
cannot use on_each_cpu() and do the same thing from the per-cpu context.
The update from the current CPU should be safe because
perf_event_disable removes the event atomically before it clears the
per-cpu watchdog_ev so it cannot change anything under running handler
feet.

The hrtimer is simply restarted (thanks to Don Zickus who has pointed
this out) if it is queued because we cannot rely it will fire&adopt to
the new sampling period before a new nmi event triggers (when the
treshold is decreased).

[akpm@linux-foundation.org: the UP version of __smp_call_function_single ended up in the wrong place]
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:25 -07:00
Michal Hocko 359e6fab66 watchdog: update watchdog attributes atomically
proc_dowatchdog doesn't synchronize multiple callers which might lead to
confusion when two parallel callers might confuse watchdog_enable_all_cpus
resp watchdog_disable_all_cpus (eg watchdog gets enabled even if
watchdog_thresh was set to 0 already).

This patch adds a local mutex which synchronizes callers to the sysctl
handler.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 17:00:25 -07:00
Linus Torvalds e288e931c1 Merge branch 'bcache' (bcache fixes from Kent Overstreet)
Merge bcache fixes from Kent Overstreet:
 "There's fixes for _three_ different data corruption bugs, all of which
  were found by users hitting them in the wild.

  The first one isn't bcache specific - in 3.11 bcache was switched to
  the bio_copy_data in fs/bio.c, and that's when the bug in that code
  was discovered, but it's also used by raid1 and pktcdvd.  (That was my
  code too, so the bug's doubly embarassing given that it was or
  should've been just a cut and paste from bcache code.  Dunno what
  happened there).

  Most of these (all the non data corruption bugs, actually) were ready
  before the merge window and have been sitting in Jens' tree, but I
  don't know what's been up with him lately..."

* emailed patches from Kent Overstreet <kmo@daterainc.com>:
  bcache: Fix flushes in writeback mode
  bcache: Fix for handling overlapping extents when reading in a btree node
  bcache: Fix a shrinker deadlock
  bcache: Fix a dumb CPU spinning bug in writeback
  bcache: Fix a flush/fua performance bug
  bcache: Fix a writeback performance regression
  bcache: Correct printf()-style format length modifier
  bcache: Fix for when no journal entries are found
  bcache: Strip endline when writing the label through sysfs
  bcache: Fix a dumb journal discard bug
  block: Fix bio_copy_data()
2013-09-24 14:42:03 -07:00
Kent Overstreet c0f04d88e4 bcache: Fix flushes in writeback mode
In writeback mode, when we get a cache flush we need to make sure we
issue a flush to the backing device.

The code for sending down an extra flush was wrong - by cloning the bio
we were probably getting flags that didn't make sense for a bare flush,
and also the old code was firing for FUA bios, for which we don't need
to send a flush to the backing device.

This was causing data corruption somehow - the mechanism was never
determined, but this patch fixes it for the users that were seeing it.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Kent Overstreet 84786438ed bcache: Fix for handling overlapping extents when reading in a btree node
btree_sort_fixup() was overly clever, because it was trying to avoid
pulling a key off the btree iterator in more than one place.

This led to a really obscure bug where we'd break early from the loop in
btree_sort_fixup() if the current key overlapped with keys in more than
one older set, and the next key it overlapped with was zero size.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Kent Overstreet a698e08c82 bcache: Fix a shrinker deadlock
GFP_NOIO means we could be getting called recursively - mca_alloc() ->
mca_data_alloc() - definitely can't use mutex_lock(bucket_lock) then.
Whoops.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Kent Overstreet 79e3dab90d bcache: Fix a dumb CPU spinning bug in writeback
schedule_timeout() != schedule_timeout_uninterruptible()

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Kent Overstreet 1394d6761b bcache: Fix a flush/fua performance bug
bch_journal_meta() was missing the flush to make the journal write
actually go down (instead of waiting up to journal_delay_ms)...

Whoops

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Kent Overstreet c2a4f3183a bcache: Fix a writeback performance regression
Background writeback works by scanning the btree for dirty data and
adding those keys into a fixed size buffer, then for each dirty key in
the keybuf writing it to the backing device.

When read_dirty() finishes and it's time to scan for more dirty data, we
need to wait for the outstanding writeback IO to finish - they still
take up slots in the keybuf (so that foreground writes can check for
them to avoid races) - without that wait, we'll continually rescan when
we'll be able to add at most a key or two to the keybuf, and that takes
locks that starves foreground IO.  Doh.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Geert Uytterhoeven 61cbd250f8 bcache: Correct printf()-style format length modifier
Fix

  drivers/md/bcache/btree.c: In function ‘bch_btree_node_read’:
  drivers/md/bcache/btree.c:259: warning: format ‘%lu’ expects type ‘long unsigned int’, but argument 3 has type ‘size_t’

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Kent Overstreet c426c4fd46 bcache: Fix for when no journal entries are found
The journal replay code didn't handle this case, causing it to go into
an infinite loop...

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Gabriel de Perthuis aee6f1cfff bcache: Strip endline when writing the label through sysfs
sysfs attributes with unusual characters have crappy failure modes
in Squeeze (udev 164); later versions of udev are unaffected.

This should make these characters more unusual.

Signed-off-by: Gabriel de Perthuis <g2p.code@gmail.com>
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Kent Overstreet 6d9d21e35f bcache: Fix a dumb journal discard bug
That switch statement was obviously wrong, leading to some sort of weird
spinning on rare occasion with discards enabled...

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:43 -07:00
Kent Overstreet 2f6cf0de02 block: Fix bio_copy_data()
The memcpy() in bio_copy_data() was using the wrong offset vars, leading
to data corruption in weird unusual setups.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.9
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-24 14:41:42 -07:00
David Vrabel 24f69373e2 xen/balloon: don't alloc page while non-preemptible
get_balloon_scratch_page() disables preemption so we cannot call
alloc_page() in between get/put_balloon_scratch_page().  Shuffle bits
around in decrease_reservation() to avoid this.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-09-24 16:22:27 -04:00
Konrad Rzeszutek Wilk a945928ea2 xen: Do not enable spinlocks before jump_label_init() has executed
xen_init_spinlocks() currently calls static_key_slow_inc() before
jump_label_init() is invoked. When CONFIG_JUMP_LABEL is set (which usually is
the case) the effect of this static_key_slow_inc() is deferred until after
jump_label_init(). This is different from when CONFIG_JUMP_LABEL is not set, in
which case the key is set immediately. Thus, depending on the value of config
option, we may observe different behavior.

In addition, when we come to __jump_label_transform() from jump_label_init(),
the key (paravirt_ticketlocks_enabled) is already enabled. On processors where
ideal_nop is not the same as default_nop this will cause a BUG() since it is
expected that before a key is enabled the latter is replaced by the former
during initialization.

To address this problem we need to move
static_key_slow_inc(&paravirt_ticketlocks_enabled) so that it is called
after jump_label_init(). We also need to make sure that this is done before
other cpus start to boot. early_initcall appears to be  a good place to do so.
(Note that we cannot move whole xen_init_spinlocks() there since pv_lock_ops
need to be set before alternative_instructions() runs.)

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
[v2: Added extra comments in the code]
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
2013-09-24 16:22:26 -04:00
Jason Gunthorpe bf4a7c054b tpm: xen-tpmfront: Remove the locality sysfs attribute
Upon deeper review it was agreed to remove the driver-unique
'locality' sysfs attribute before it is present in a released
kernel.

The attribute was introduced in e2683957fb
during the 3.12 merge window, so this patch needs to go in before
3.12 is released.

The hope is to have a well defined locality API that all the other
locality aware drivers can use, perhaps in 3.13.

Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
2013-09-24 16:15:15 -04:00
Jason Gunthorpe 56be88954b tpm: xen-tpmfront: Fix default durations
All the default durations were being set to 10 minutes which is
way too long for the timeouts. Normal values for the longest
duration are around 5 mins, and short duration ar around .5s.

Further, these are just the default, tpm_get_timeouts will set
them to values from the TPM (or throw an error).

Just remove them.

Acked-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-09-24 16:14:55 -04:00
Daniel Vetter 67c72a1225 drm/i915: preserve pipe A quirk in i9xx_set_pipeconf
This regression has been introduced in

commit 9f11a9e4e5
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Thu Jun 13 00:54:58 2013 +0200

    drm/i915: set up PIPECONF explicitly for i9xx/vlv platforms

Ville brough up the idea that this is just the pipe A quirk gone
wrong.

Note that after resume the bios might or might not have enabled pipe A
already.  We have a bit of magic to make sure that on resume we set up
a decent mode for pipe A, but I fear if I just smash pipe A to always
on we'd enable it in a bogus state and hang the hw. Hence the
readback.

v2: Clarify the logic a bit as suggested by Chris. Also amend the
commit message to clarify why we don't unconditionally enable the
pipe.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=66462
References: https://lkml.org/lkml/2013/8/26/238
Cc: Meelis Roos <mroos@ut.ee>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
[danvet: Use |= instead of = as suggested by Chris.]
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-09-24 20:39:00 +02:00
Daniel Vetter 1062b81598 drm/i915/tv: clear adjusted_mode.flags
The native TV encoder has it's own flags to adjust sync modes and
enabled interlaced modes which are totally irrelevant for the adjusted
mode. This worked out nicely since the input modes used by both the
load detect code and reported in the ->get_modes callbacks all have no
flags set, and we also don't fill out any of them in the ->get_config
callback.

This changed with the additional sanitation done with

commit 2960bc9cce
Author: Imre Deak <imre.deak@intel.com>
Date:   Tue Jul 30 13:36:32 2013 +0300

    drm/i915: make user mode sync polarity setting explicit

sinc now the "no flags at all" state wouldn't fit through core code
any more. So fix this up again by explicitly clearing the flags in the
->compute_config callback.

Aside: We have zero checking in place to make sure that the requested
mode is indeed the right input mode we want for the selected TV mode.
So we'll happily fall over if userspace tries to pull us.  But that's
definitely work for a different patch series. So just add a FIXME
comment for now.

Reported-by: Knut Petersen <Knut_Petersen@t-online.de>
Cc: Knut Petersen <Knut_Petersen@t-online.de>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Knut Petersen <Knut_Petersen@t-online.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-09-24 20:38:59 +02:00
Jani Nikula 8d16f25821 drm/i915/dp: increase i2c-over-aux retry interval on AUX DEFER
There is no clear cut rules or specs for the retry interval, as there
are many factors that affect overall response time. Increase the
interval, and even more so on branch devices which may have limited i2c
bit rates.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reference: https://bugs.freedesktop.org/show_bug.cgi?id=60263
Tested-by: Nicolas Suzor <nic@suzor.com>
Reviewed-by: Todd Previte <tprevite@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-09-24 20:38:54 +02:00