Commit Graph

375733 Commits

Author SHA1 Message Date
Joern Engel
ccf5ae83a6 target: close target_put_sess_cmd() vs. core_tmr_abort_task() race
It is possible for one thread to to take se_sess->sess_cmd_lock in
core_tmr_abort_task() before taking a reference count on
se_cmd->cmd_kref, while another thread in target_put_sess_cmd() drops
se_cmd->cmd_kref before taking se_sess->sess_cmd_lock.

This introduces kref_put_spinlock_irqsave() and uses it in
target_put_sess_cmd() to close the race window.

Signed-off-by: Joern Engel <joern@logfs.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-05-15 01:47:35 -07:00
Joern Engel
a1321ddd27 target: removed unused transport_state flag
Signed-off-by: Joern Engel <joern@logfs.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-05-15 01:46:53 -07:00
Nicholas Bellinger
d2bdbee0d9 target/iblock: Fix WCE=1 + DPOFUA=1 backend WRITE regression
This patch fixes a regression bug introduced in v3.9-rc1 where if the
underlying struct block_device for a IBLOCK backend is configured with
WCE=1 + DPOFUA=1 settings, the rw = WRITE assignment no longer occurs
in iblock_execute_rw(), and rw = 0 is passed to iblock_submit_bios()
in effect causing a READ bio operation to occur.

The offending commit is:

commit d0c8b259f8
Author: Nicholas Bellinger <nab@linux-iscsi.org>
Date:   Tue Jan 29 22:10:06 2013 -0800

    target/iblock: Use backend REQ_FLUSH hint for WriteCacheEnabled status

Note the WCE=1 + DPOFUA=0, WCE=0 + DPOFUA=1, and WCE=0 + DPOFUA=0 cases
are not affected by this regression bug.

Reported-by: Chris Boot <bootc@bootc.net>
Tested-by: Chris Boot <bootc@bootc.net>
Reported-by: Hannes Reinecke <hare@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-05-15 01:46:34 -07:00
John Stultz
b4f711ee03 time: Revert ALWAYS_USE_PERSISTENT_CLOCK compile time optimizaitons
Kay Sievers noted that the ALWAYS_USE_PERSISTENT_CLOCK config,
which enables some minor compile time optimization to avoid
uncessary code in mostly the suspend/resume path could cause
problems for userland.

In particular, the dependency for RTC_HCTOSYS on
!ALWAYS_USE_PERSISTENT_CLOCK, which avoids setting the time
twice and simplifies suspend/resume, has the side effect
of causing the /sys/class/rtc/rtcN/hctosys flag to always be
zero, and this flag is commonly used by udev to setup the
/dev/rtc symlink to /dev/rtcN, which can cause pain for
older applications.

While the udev rules could use some work to be less fragile,
breaking userland should strongly be avoided. Additionally
the compile time optimizations are fairly minor, and the code
being optimized is likely to be reworked in the future, so
lets revert this change.

Reported-by: Kay Sievers <kay@vrfy.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Cc: stable <stable@vger.kernel.org> #3.9
Cc: Feng Tang <feng.tang@intel.com>
Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Link: http://lkml.kernel.org/r/1366828376-18124-1-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-05-14 20:54:06 +02:00
Marc Dionne
ad7b1f841f workqueue: Make schedule_work() available again to non GPL modules
Commit 8425e3d5bd ("workqueue: inline trivial wrappers") changed
schedule_work() and schedule_delayed_work() to inline wrappers,
but these rely on some symbols that are EXPORT_SYMBOL_GPL, while
the original functions were EXPORT_SYMBOL.  This has the effect of
changing the licensing requirement for these functions and making
them unavailable to non GPL modules.

Make them available again by removing the restriction on the
required symbols.

Signed-off-by: Marc Dionne <marc.dionne@your-file-system.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2013-05-14 11:52:51 -07:00
Joonsoo Kim
8f174b1175 workqueue: correct handling of the pool spin_lock
When we fail to mutex_trylock(), we release the pool spin_lock and do
mutex_lock(). After that, we should regrab the pool spin_lock, but,
regrabbing is missed in current code. So correct it.

Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2013-05-14 11:48:15 -07:00
Paul E. McKenney
6faf72834d rcu: Fix comparison sense in rcu_needs_cpu()
Commit c0f4dfd4f (rcu: Make RCU_FAST_NO_HZ take advantage of numbered
callbacks) introduced a bug that can result in excessively long grace
periods.  This bug reverse the senes of the "if" statement checking
for lazy callbacks, so that RCU takes a lazy approach when there are
in fact non-lazy callbacks.  This can result in excessive boot, suspend,
and resume times.

This commit therefore fixes the sense of this "if" statement.

Reported-by: Borislav Petkov <bp@alien8.de>
Reported-by: Bjørn Mork <bjorn@mork.no>
Reported-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Bjørn Mork <bjorn@mork.no>
Tested-by: Joerg Roedel <joro@8bytes.org>
2013-05-14 10:53:41 -07:00
Linus Torvalds
b973425cbb Fixed regressions (two stability regressions and a performance
regression) introduced during the 3.10-rc1 merge window.  Also
 included is a bug fix relating to allocating blocks after resizing an
 ext3 file system when using the ext4 file system driver.
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Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 update from Ted Ts'o:
 "Fixed regressions (two stability regressions and a performance
  regression) introduced during the 3.10-rc1 merge window.

  Also included is a bug fix relating to allocating blocks after
  resizing an ext3 file system when using the ext4 file system driver"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  jbd,jbd2: fix oops in jbd2_journal_put_journal_head()
  ext4: revert "ext4: use io_end for multiple bios"
  ext4: limit group search loop for non-extent files
  ext4: fix fio regression
2013-05-14 09:30:54 -07:00
Linus Torvalds
7fb30d2b60 Merge branch 'for-3.10-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue fix from Tejun Heo:
 "A fix for a workqueue_congested() regression that broke fscache"

* 'for-3.10-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: workqueue_congested() shouldn't translate WORK_CPU_UNBOUND into node number
2013-05-14 09:06:29 -07:00
Tirupathi Reddy
42a5cf46cd timer: Don't reinitialize the cpu base lock during CPU_UP_PREPARE
An inactive timer's base can refer to a offline cpu's base.

In the current code, cpu_base's lock is blindly reinitialized each
time a CPU is brought up. If a CPU is brought online during the period
that another thread is trying to modify an inactive timer on that CPU
with holding its timer base lock, then the lock will be reinitialized
under its feet. This leads to following SPIN_BUG().

<0> BUG: spinlock already unlocked on CPU#3, kworker/u:3/1466
<0> lock: 0xe3ebe000, .magic: dead4ead, .owner: kworker/u:3/1466, .owner_cpu: 1
<4> [<c0013dc4>] (unwind_backtrace+0x0/0x11c) from [<c026e794>] (do_raw_spin_unlock+0x40/0xcc)
<4> [<c026e794>] (do_raw_spin_unlock+0x40/0xcc) from [<c076c160>] (_raw_spin_unlock+0x8/0x30)
<4> [<c076c160>] (_raw_spin_unlock+0x8/0x30) from [<c009b858>] (mod_timer+0x294/0x310)
<4> [<c009b858>] (mod_timer+0x294/0x310) from [<c00a5e04>] (queue_delayed_work_on+0x104/0x120)
<4> [<c00a5e04>] (queue_delayed_work_on+0x104/0x120) from [<c04eae00>] (sdhci_msm_bus_voting+0x88/0x9c)
<4> [<c04eae00>] (sdhci_msm_bus_voting+0x88/0x9c) from [<c04d8780>] (sdhci_disable+0x40/0x48)
<4> [<c04d8780>] (sdhci_disable+0x40/0x48) from [<c04bf300>] (mmc_release_host+0x4c/0xb0)
<4> [<c04bf300>] (mmc_release_host+0x4c/0xb0) from [<c04c7aac>] (mmc_sd_detect+0x90/0xfc)
<4> [<c04c7aac>] (mmc_sd_detect+0x90/0xfc) from [<c04c2504>] (mmc_rescan+0x7c/0x2c4)
<4> [<c04c2504>] (mmc_rescan+0x7c/0x2c4) from [<c00a6a7c>] (process_one_work+0x27c/0x484)
<4> [<c00a6a7c>] (process_one_work+0x27c/0x484) from [<c00a6e94>] (worker_thread+0x210/0x3b0)
<4> [<c00a6e94>] (worker_thread+0x210/0x3b0) from [<c00aad9c>] (kthread+0x80/0x8c)
<4> [<c00aad9c>] (kthread+0x80/0x8c) from [<c000ea80>] (kernel_thread_exit+0x0/0x8)

As an example, this particular crash occurred when CPU #3 is executing
mod_timer() on an inactive timer whose base is refered to offlined CPU
#2.  The code locked the timer_base corresponding to CPU #2. Before it
could proceed, CPU #2 came online and reinitialized the spinlock
corresponding to its base. Thus now CPU #3 held a lock which was
reinitialized. When CPU #3 finally ended up unlocking the old cpu_base
corresponding to CPU #2, we hit the above SPIN_BUG().

CPU #0		CPU #3				       CPU #2
------		-------				       -------
.....		 ......				      <Offline>
		mod_timer()
		 lock_timer_base
		   spin_lock_irqsave(&base->lock)

cpu_up(2)	 .....				        ......
							init_timers_cpu()
....		 .....				    	spin_lock_init(&base->lock)
.....		   spin_unlock_irqrestore(&base->lock)  ......
		   <spin_bug>

Allocation of per_cpu timer vector bases is done only once under
"tvec_base_done[]" check. In the current code, spinlock_initialization
of base->lock isn't under this check. When a CPU is up each time the
base lock is reinitialized. Move base spinlock initialization under
the check.

Signed-off-by: Tirupathi Reddy <tirupath@codeaurora.org>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1368520142-4136-1-git-send-email-tirupath@codeaurora.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-05-14 17:59:18 +02:00
Srivatsa S. Bhat
b47430d3ad rcu/idle: Wrap cpu-idle poll mode within rcu_idle_enter/exit
Bjørn Mork reported the following warning when running powertop.

[   49.289034] ------------[ cut here ]------------
[   49.289055] WARNING: at kernel/rcutree.c:502 rcu_eqs_exit_common.isra.48+0x3d/0x125()
[   49.289244] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.10.0-bisect-rcu-warn+ #107
[   49.289251]  ffffffff8157d8c8 ffffffff81801e28 ffffffff8137e4e3 ffffffff81801e68
[   49.289260]  ffffffff8103094f ffffffff81801e68 0000000000000000 ffff88023afcd9b0
[   49.289268]  0000000000000000 0140000000000000 ffff88023bee7700 ffffffff81801e78
[   49.289276] Call Trace:
[   49.289285]  [<ffffffff8137e4e3>] dump_stack+0x19/0x1b
[   49.289293]  [<ffffffff8103094f>] warn_slowpath_common+0x62/0x7b
[   49.289300]  [<ffffffff8103097d>] warn_slowpath_null+0x15/0x17
[   49.289306]  [<ffffffff810a9006>] rcu_eqs_exit_common.isra.48+0x3d/0x125
[   49.289314]  [<ffffffff81079b49>] ? trace_hardirqs_off_caller+0x37/0xa6
[   49.289320]  [<ffffffff810a9692>] rcu_idle_exit+0x85/0xa8
[   49.289327]  [<ffffffff8107076e>] trace_cpu_idle_rcuidle+0xae/0xff
[   49.289334]  [<ffffffff810708b1>] cpu_startup_entry+0x72/0x115
[   49.289341]  [<ffffffff813689e5>] rest_init+0x149/0x150
[   49.289347]  [<ffffffff8136889c>] ? csum_partial_copy_generic+0x16c/0x16c
[   49.289355]  [<ffffffff81a82d34>] start_kernel+0x3f0/0x3fd
[   49.289362]  [<ffffffff81a8274c>] ? repair_env_string+0x5a/0x5a
[   49.289368]  [<ffffffff81a82481>] x86_64_start_reservations+0x2a/0x2c
[   49.289375]  [<ffffffff81a82550>] x86_64_start_kernel+0xcd/0xd1
[   49.289379] ---[ end trace 07a1cc95e29e9036 ]---

The warning is that 'rdtp->dynticks' has an unexpected value, which roughly
translates to - the calls to rcu_idle_enter() and rcu_idle_exit() were not
made in the correct order, or otherwise messed up.

And Bjørn's painstaking debugging indicated that this happens when the idle
loop enters the poll mode. Looking at the poll function cpu_idle_poll(), and
the implementation of trace_cpu_idle_rcuidle(), the problem becomes very clear:
cpu_idle_poll() lacks calls to rcu_idle_enter/exit(), and trace_cpu_idle_rcuidle()
calls them in the reverse order - first rcu_idle_exit(), and then rcu_idle_enter().
Hence the even/odd alternative sequencing of rdtp->dynticks goes for a toss.

And powertop readily triggers this because powertop uses the idle-tracing
infrastructure extensively.

So, to fix this, wrap the code in cpu_idle_poll() within rcu_idle_enter/exit(),
so that it blends properly with the calls inside trace_cpu_idle_rcuidle() and
thus get the function ordering right.

Reported-and-tested-by: Bjørn Mork <bjorn@mork.no>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Dipankar Sarma <dipankar@in.ibm.com>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/519169BF.4080208@linux.vnet.ibm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-05-14 17:43:29 +02:00
Thomas Gleixner
f7ea0fd639 tick: Don't invoke tick_nohz_stop_sched_tick() if the cpu is offline
commit 5b39939a4 (nohz: Move ts->idle_calls incrementation into strict
idle logic) moved code out of tick_nohz_stop_sched_tick() and missed
to bail out when the cpu is offline. That's causing subsequent
failures as an offline CPU is supposed to die and not to fiddle with
nohz magic.

Return false in can_stop_idle_tick() if the cpu is offline.

Reported-and-tested-by: Jiri Kosina <jkosina@suse.cz>
Reported-and-tested-by: Prarit Bhargava <prarit@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1305132138160.2863@ionos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-05-14 17:40:31 +02:00
Linus Torvalds
a2c7a54fcc Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
Pull powerpc fixes from Benjamin Herrenschmidt:
 "This is mostly bug fixes (some of them regressions, some of them I
  deemed worth merging now) along with some patches from Li Zhong
  hooking up the new context tracking stuff (for the new full NO_HZ)"

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (25 commits)
  powerpc: Set show_unhandled_signals to 1 by default
  powerpc/perf: Fix setting of "to" addresses for BHRB
  powerpc/pmu: Fix order of interpreting BHRB target entries
  powerpc/perf: Move BHRB code into CONFIG_PPC64 region
  powerpc: select HAVE_CONTEXT_TRACKING for pSeries
  powerpc: Use the new schedule_user API on userspace preemption
  powerpc: Exit user context on notify resume
  powerpc: Exception hooks for context tracking subsystem
  powerpc: Syscall hooks for context tracking subsystem
  powerpc/booke64: Fix kernel hangs at kernel_dbg_exc
  powerpc: Fix irq_set_affinity() return values
  powerpc: Provide __bswapdi2
  powerpc/powernv: Fix starting of secondary CPUs on OPALv2 and v3
  powerpc/powernv: Detect OPAL v3 API version
  powerpc: Fix MAX_STACK_TRACE_ENTRIES too low warning again
  powerpc: Make CONFIG_RTAS_PROC depend on CONFIG_PROC_FS
  powerpc: Bring all threads online prior to migration/hibernation
  powerpc/rtas_flash: Fix validate_flash buffer overflow issue
  powerpc/kexec: Fix kexec when using VMX optimised memcpy
  powerpc: Fix build errors STRICT_MM_TYPECHECKS
  ...
2013-05-14 07:43:11 -07:00
Rafael J. Wysocki
75e1d828c6 Merge branch 'pm-fixes'
* pm-fixes:
  PM / hibernate: Correct documentation
  PM / Documentation: remove inaccurate suspend/hibernate transition lantency statement
  PM: Documentation update for freeze state
  PM: Avoid calling kfree() under spinlock in dev_pm_put_subsys_data()
2013-05-14 15:12:17 +02:00
Rafael J. Wysocki
c01782d819 Merge branch 'acpi-fixes'
* acpi-fixes:
  ACPI / AC: Add sleep quirk for Thinkpad e530
  ACPI / EC: Restart transaction even when the IBF flag set
  ACPI video: ignore BIOS initial backlight value for HP 1000
  ACPI: Fix section to __init. Align with usage in acpixf.h
  ACPI / PM: Move processor suspend/resume to syscore_ops
2013-05-14 15:12:10 +02:00
Rafael J. Wysocki
d5a2fa27ec Merge branch 'pm-cpufreq'
* pm-cpufreq:
  cpufreq / intel_pstate: use vzalloc() instead of vmalloc()/memset(0)
  cpufreq, ondemand: Remove leftover debug line
  cpufreq / kirkwood: don't check resource with devm_ioremap_resource
  cpufreq / intel_pstate: remove #ifdef MODULE compile fence
  cpufreq / intel_pstate: Remove idle mode PID
  cpufreq / intel_pstate: fix ffmpeg regression
  cpufreq / intel_pstate: use lowest requested max performance
  cpufreq / intel_pstate: remove idle time and duration from sample and calculations
  cpufreq: Fix incorrect dependecies for ARM SA11xx drivers
  cpufreq: ARM big LITTLE: Fix Kconfig entries
  cpufreq: cpufreq-cpu0: Free parent node for error cases
  cpufreq: cpufreq-cpu0: defer probe when regulator is not ready
  cpufreq: Issue CPUFREQ_GOV_POLICY_EXIT notifier before dropping policy refcount
  cpufreq: governors: Fix CPUFREQ_GOV_POLICY_{INIT|EXIT} notifiers
  cpufreq: ARM big LITTLE: Improve print message
  cpufreq: ARM big LITTLE: Move cpu_to_cluster() to arm_big_little.h
  cpufreq: ARM big LITTLE DT: Return CPUFREQ_ETERNAL if clock-latency isn't found
  cpufreq: ARM big LITTLE DT: Return correct transition latency
  cpufreq: ARM big LITTLE: Select PM_OPP
2013-05-14 15:11:55 +02:00
Benjamin Herrenschmidt
e34166ad63 powerpc: Set show_unhandled_signals to 1 by default
Just like other architectures

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 18:01:04 +10:00
Michael Neuling
691231846c powerpc/perf: Fix setting of "to" addresses for BHRB
Currently we only set the "to" address in the branch stack when the CPU
explicitly gives us a value.  Unfortunately it only does this for XL form
branches (eg blr, bctr, bctar) and not I and B form branches (eg b, bc).

Fortunately if we read the instruction from memory we can extract the offset of
a branch and calculate the target address.

This adds a function power_pmu_bhrb_to() to calculate the target/to address of
the corresponding I and B form branches.  It handles branches in both user and
kernel spaces.  It also plumbs this into the perf brhb reading code.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 16:00:22 +10:00
Michael Neuling
506e70d132 powerpc/pmu: Fix order of interpreting BHRB target entries
The current Branch History Rolling Buffer (BHRB) code misinterprets the order
of entries in the hardware buffer.  It assumes that a branch target address
will be read _after_ its corresponding branch.  In reality the branch target
comes before (lower mfbhrb entry) it's corresponding branch.

This is a rewrite of the code to take this into account.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 16:00:22 +10:00
Michael Neuling
d52f2dc40b powerpc/perf: Move BHRB code into CONFIG_PPC64 region
The new Branch History Rolling buffer (BHRB) code is only useful on 64bit
processors, so move it into the #ifdef CONFIG_PPC64 region.

This avoids code bloat on 32bit systems.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 16:00:21 +10:00
Li Zhong
a1797b2fd2 powerpc: select HAVE_CONTEXT_TRACKING for pSeries
Start context tracking support from pSeries.

Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 16:00:21 +10:00
Li Zhong
5d1c574511 powerpc: Use the new schedule_user API on userspace preemption
This patch corresponds to
[PATCH] x86: Use the new schedule_user API on userspace preemption
  commit 0430499ce9

Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 16:00:20 +10:00
Li Zhong
106ed886ab powerpc: Exit user context on notify resume
This patch allows RCU usage in do_notify_resume, e.g. signal handling.
It corresponds to
[PATCH] x86: Exit RCU extended QS on notify resume
  commit edf55fda35

Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 16:00:20 +10:00
Li Zhong
ba12eedee3 powerpc: Exception hooks for context tracking subsystem
This is the exception hooks for context tracking subsystem, including
data access, program check, single step, instruction breakpoint, machine check,
alignment, fp unavailable, altivec assist, unknown exception, whose handlers
might use RCU.

This patch corresponds to
[PATCH] x86: Exception hooks for userspace RCU extended QS
  commit 6ba3c97a38

But after the exception handling moved to generic code, and some changes in
following two commits:
56dd9470d7
  context_tracking: Move exception handling to generic code
6c1e0256fa
  context_tracking: Restore correct previous context state on exception exit

it is able for exception hooks to use the generic code above instead of a
redundant arch implementation.

Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 16:00:19 +10:00
Li Zhong
22ecbe8dce powerpc: Syscall hooks for context tracking subsystem
This is the syscall slow path hooks for context tracking subsystem,
corresponding to
[PATCH] x86: Syscall hooks for userspace RCU extended QS
  commit bf5a3c13b9

TIF_MEMDIE is moved to the second 16-bits (with value 17), as it seems there
is no asm code using it. TIF_NOHZ is added to _TIF_SYCALL_T_OR_A, so it is
better for it to be in the same 16 bits with others in the group, so in the
asm code, andi. with this group could work.

Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 16:00:19 +10:00
Scott Wood
6cecf76b47 powerpc/booke64: Fix kernel hangs at kernel_dbg_exc
MSR_DE is not cleared on entry to the kernel, and we don't clear it
explicitly outside of debug code.  If we have MSR_DE set in
prime_debug_regs(), and the new thread has events enabled in DBCR0
(e.g.  ICMP is set in thread->dbsr0, even though it was cleared in the
real DBCR0 when the thread got scheduled out), we'll end up taking a
debug exception in the kernel when DBCR0 is loaded.  DSRR0 will not
point to an exception vector, and the kernel ends up hanging at
kernel_dbg_exc.  Fix this by always clearing MSR_DE when we load new
debug state.

Another observed source of kernel_dbg_exc hangs is with the branch
taken event.  If this event is active, but we take a non-debug trap
(e.g. a TLB miss or an asynchronous interrupt) before the next branch.
We end up taking a branch-taken debug exception on the initial branch
instruction of the exception vector, but because the debug exception is
DBSR_BT rather than DBSR_IC we branch to kernel_dbg_exc before even
checking the DSRR0 address.  Fix this by checking for DBSR_BT as well
as DBSR_IC, which is what 32-bit does and what the comments suggest was
intended in the 64-bit code as well.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 16:00:19 +10:00
Alexander Gordeev
dcb615aef9 powerpc: Fix irq_set_affinity() return values
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 16:00:18 +10:00
David Woodhouse
ca9d7aea59 powerpc: Provide __bswapdi2
Some versions of GCC apparently expect this to be provided by libgcc.

Updates from Mikey to fix 32 bit version and adding "r" to registers.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 16:00:17 +10:00
Benjamin Herrenschmidt
b2b48584df powerpc/powernv: Fix starting of secondary CPUs on OPALv2 and v3
The current code fails to handle kexec on OPALv2. This fixes it
and adds code to improve the situation on OPALv3 where we can
query the CPU status from the firmware and decide what to do
based on that.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 15:12:31 +10:00
Benjamin Herrenschmidt
75b93da43a powerpc/powernv: Detect OPAL v3 API version
Future firmwares will support that new version

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 15:10:02 +10:00
Li Zhong
af945cf4bf powerpc: Fix MAX_STACK_TRACE_ENTRIES too low warning again
Saw this warning again, and this time from the ret_from_fork path.

It seems we could clear the back chain earlier in copy_thread(), which
could cover both path, and also fix potential lockdep usage in
schedule_tail(), or exception occurred before we clear the back chain.

Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 14:36:35 +10:00
Michael Ellerman
b80ec3dc8e powerpc: Make CONFIG_RTAS_PROC depend on CONFIG_PROC_FS
We are getting build errors with CONFIG_PROC_FS=n:

arch/powerpc/kernel/rtas_flash.c
   In function 'rtas_flash_init':
  745:33: error: unused variable 'f' [-Werror=unused-variable]

But rtas_flash.c should not be built when CONFIG_PROC_FS=n, beacause all
it does is provide a /proc interface to the RTAS flash routines.

CONFIG_RTAS_FLASH already depends on CONFIG_RTAS_PROC, to indicate that
it depends on the RTAS proc support, but CONFIG_RTAS_PROC does not
depend on CONFIG_PROC_FS. So fix that.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 14:36:32 +10:00
Robert Jennings
120496ac2d powerpc: Bring all threads online prior to migration/hibernation
This patch brings online all threads which are present but not online
prior to migration/hibernation.  After migration/hibernation those
threads are taken back offline.

During migration/hibernation all online CPUs must call H_JOIN, this is
required by the hypervisor.  Without this patch, threads that are offline
(H_CEDE'd) will not be woken to make the H_JOIN call and the OS will be
deadlocked (all threads either JOIN'd or CEDE'd).

Cc: <stable@kernel.org>
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 14:36:29 +10:00
Vasant Hegde
a94a14720e powerpc/rtas_flash: Fix validate_flash buffer overflow issue
ibm,validate-flash-image RTAS call output buffer contains 150 - 200
bytes of data on latest system. Presently we have output
buffer size as 64 bytes and we use sprintf to copy data from
RTAS buffer to local buffer. This causes kernel oops (see below
call trace).

This patch increases local buffer size to 256 and also uses
snprintf instead of sprintf to copy data from RTAS buffer.

Kernel call trace :
-------------------
Oops: Kernel access of bad area, sig: 11 [#1]
SMP NR_CPUS=1024 NUMA pSeries
Modules linked in: nfs fscache lockd auth_rpcgss nfs_acl sunrpc fuse loop dm_mod ipv6 ipv6_lib usb_storage ehea(X) sr_mod qlge ses cdrom enclosure st be2net sg ext3 jbd mbcache usbhid hid ohci_hcd ehci_hcd usbcore qla2xxx usb_common sd_mod crc_t10dif scsi_dh_hp_sw scsi_dh_rdac scsi_dh_alua scsi_dh_emc scsi_dh lpfc scsi_transport_fc scsi_tgt ipr(X) libata scsi_mod
Supported: Yes
NIP: 4520323031333130 LR: 4520323031333130 CTR: 0000000000000000
REGS: c0000001b91779b0 TRAP: 0400   Tainted: G            X  (3.0.13-0.27-ppc64)
MSR: 8000000040009032 <EE,ME,IR,DR>  CR: 44022488  XER: 20000018
TASK = c0000001bca1aba0[4736] 'cat' THREAD: c0000001b9174000 CPU: 36
GPR00: 4520323031333130 c0000001b9177c30 c000000000f87c98 000000000000009b
GPR04: c0000001b9177c4a 000000000000000b 3520323031333130 2032303133313031
GPR08: 3133313031350a4d 000000000000009b 0000000000000000 c0000000003664a4
GPR12: 0000000022022448 c000000003ee6c00 0000000000000002 00000000100e8a90
GPR16: 00000000100cb9d8 0000000010093370 000000001001d310 0000000000000000
GPR20: 0000000000008000 00000000100fae60 000000000000005e 0000000000000000
GPR24: 0000000010129350 46573738302e3030 2046573738302e30 300a4d4720323031
GPR28: 333130313520554e 4b4e4f574e0a4d47 2032303133313031 3520323031333130
NIP [4520323031333130] 0x4520323031333130
LR [4520323031333130] 0x4520323031333130
Call Trace:
[c0000001b9177c30] [4520323031333130] 0x4520323031333130 (unreliable)
Instruction dump:
XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX

Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 14:36:26 +10:00
Anton Blanchard
79c66ce8f6 powerpc/kexec: Fix kexec when using VMX optimised memcpy
commit b3f271e86e (powerpc: POWER7 optimised memcpy using VMX and
enhanced prefetch) uses VMX when it is safe to do so (ie not in
interrupt). It also looks at the task struct to decide if we have to
save the current tasks' VMX state.

kexec calls memcpy() at a point where the task struct may have been
overwritten by the new kexec segments. If it has been overwritten
then when memcpy -> enable_altivec looks up current->thread.regs->msr
we get a cryptic oops or lockup.

I also notice we aren't initialising thread_info->cpu, which means
smp_processor_id is broken. Fix that too.

Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@vger.kernel.org> # 3.6+
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 14:36:23 +10:00
Aneesh Kumar K.V
83d5e64b7e powerpc: Fix build errors STRICT_MM_TYPECHECKS
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 14:36:20 +10:00
Aneesh Kumar K.V
613e60a661 powerpc/mm: Use the correct mask value when looking at pgtable address
Our pgtable are 2*sizeof(pte_t)*PTRS_PER_PTE which is PTE_FRAG_SIZE.
Instead of depending on frag size, mask with PMD_MASKED_BITS.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-14 14:36:17 +10:00
Linus Torvalds
674825d050 Xen ARM initialization fixes.
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Merge tag 'fixes-for-3.10-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/sstabellini/xen

Pull Xen/arm fixes from Stefano Stabellini:
 "This contains a couple of Xen on ARM initialization fixes and a patch
  to improve error handling"

* tag 'fixes-for-3.10-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/sstabellini/xen:
  xen/arm: rename xen_secondary_init and run it on every online cpu
  xen/arm: do not handle VCPUOP_register_vcpu_info failures
  xen/arm: initialize pm functions later
2013-05-13 19:03:49 -07:00
Borislav Petkov
6bc08ed023 PM / hibernate: Correct documentation
Correct the meaning of PM_HIBERNATION_PREPARE in the docs.

References: http://lkml.kernel.org/r/20130512162717.GA6305@pd.tnic
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-05-14 01:58:43 +02:00
Linus Torvalds
c83bb88589 Merge branch 'parisc-for-3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc update from Helge Deller:
 "The second round of parisc updates for 3.10 includes build fixes and
  enhancements to utilize irq stacks, fixes SMP races when updating PTE
  and TLB entries by proper locking and makes the search for the correct
  cross compiler more robust on Debian and Gentoo."

* 'parisc-for-3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: make default cross compiler search more robust (v3)
  parisc: fix SMP races when updating PTE and TLB entries in entry.S
  parisc: implement irq stacks - part 2 (v2)
2013-05-13 16:49:59 -07:00
Zhang Rui
86fd03d160 PM / Documentation: remove inaccurate suspend/hibernate transition lantency statement
The lantency of the transition from suspend and hibernate is
platform-dependent.  Thus we should not refer the lantency in the
documentation.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-05-14 01:46:50 +02:00
Zhang Rui
dc5aeae4f9 PM: Documentation update for freeze state
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-05-14 01:41:37 +02:00
Wei Yongjun
b57ffac5e5 cpufreq / intel_pstate: use vzalloc() instead of vmalloc()/memset(0)
Use vzalloc() instead of vmalloc() and memset(0).

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-05-14 01:39:28 +02:00
Jaccon Bastiaansen
6eabb3301b ARM: 7720/1: ARM v6/v7 cmpxchg64 shouldn't clear upper 32 bits of the old/new value
The implementation of cmpxchg64() for the ARM v6 and v7 architecture
casts parameter 2 and 3 (the old and new 64bit values) to an unsigned
long before calling the atomic_cmpxchg64() function. This clears
the top 32 bits of the old and new values, resulting in the wrong
values being compare-exchanged. Luckily, this only appears to be used
for 64-bit sched_clock, which we don't (yet) have on ARM.

This bug was introduced by commit 3e0f5a15f5 ("ARM: 7404/1: cmpxchg64:
use atomic64 and local64 routines for cmpxchg64").

Cc: <stable@vger.kernel.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jaccon Bastiaansen <jaccon.bastiaansen@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-05-13 23:42:24 +01:00
Linus Torvalds
dbbffe6898 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:
 "Several small bug fixes all over:

   1) be2net driver uses wrong payload length when submitting MAC list
      get requests to the chip.  From Sathya Perla.

   2) Fix mwifiex memory leak on driver unload, from Amitkumar Karwar.

   3) Prevent random memory access in batman-adv, from Marek Lindner.

   4) batman-adv doesn't check for pskb_trim_rcsum() errors, also from
      Marek Lindner.

   5) Fix fec crashes on rapid link up/down, from Frank Li.

   6) Fix inner protocol grovelling in GSO, from Pravin B Shelar.

   7) Link event validation fix in qlcnic from Rajesh Borundia.

   8) Not all FEC chips can support checksum offload, fix from Shawn
      Guo.

   9) EXPORT_SYMBOL + inline doesn't make any sense, from Denis Efremov.

  10) Fix race in passthru mode during device removal in macvlan, from
      Jiri Pirko.

  11) Fix RCU hash table lookup socket state race in ipv6, leading to
      NULL pointer derefs, from Eric Dumazet.

  12) Add several missing HAS_DMA kconfig dependencies, from Geert
      Uyttterhoeven.

  13) Fix bogus PCI resource management in 3c59x driver, from Sergei
      Shtylyov.

  14) Fix info leak in ipv6 GRE tunnel driver, from Amerigo Wang.

  15) Fix device leak in ipv6 IPSEC policy layer, from Cong Wang.

  16) DMA mapping leak fix in qlge from Thadeu Lima de Souza Cascardo.

  17) Missing iounmap on probe failure in bna driver, from Wei Yongjun."

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (40 commits)
  bna: add missing iounmap() on error in bnad_init()
  qlge: fix dma map leak when the last chunk is not allocated
  xfrm6: release dev before returning error
  ipv6,gre: do not leak info to user-space
  virtio_net: use default napi weight by default
  emac: Fix EMAC soft reset on 460EX/GT
  3c59x: fix PCI resource management
  caif: CAIF_VIRTIO should depend on HAS_DMA
  net/ethernet: MACB should depend on HAS_DMA
  net/ethernet: ARM_AT91_ETHER should depend on HAS_DMA
  net/wireless: ATH9K should depend on HAS_DMA
  net/ethernet: STMMAC_ETH should depend on HAS_DMA
  net/ethernet: NET_CALXEDA_XGMAC should depend on HAS_DMA
  ipv6: do not clear pinet6 field
  macvlan: fix passthru mode race between dev removal and rx path
  ipv4: ip_output: remove inline marking of EXPORT_SYMBOL functions
  net/mlx4: Strengthen VLAN tags/priorities enforcement in VST mode
  net/mlx4_core: Add missing report on VST and spoof-checking dev caps
  net: fec: enable hardware checksum only on imx6q-fec
  qlcnic: Fix validation of link event command.
  ...
2013-05-13 13:25:36 -07:00
Helge Deller
6880b0150a parisc: make default cross compiler search more robust (v3)
People/distros vary how they prefix the toolchain name for 64bit builds.
Rather than enforce one convention over another, add a for loop which
does a search for all the general prefixes.

For 64bit builds, we now search for (in order):
	hppa64-unknown-linux-gnu
	hppa64-linux-gnu
	hppa64-linux

For 32bit builds, we look for:
	hppa-unknown-linux-gnu
	hppa-linux-gnu
	hppa-linux
	hppa2.0-unknown-linux-gnu
	hppa2.0-linux-gnu
	hppa2.0-linux
	hppa1.1-unknown-linux-gnu
	hppa1.1-linux-gnu
	hppa1.1-linux

This patch was initiated by Mike Frysinger, with feedback from Jeroen
Roovers, John David Anglin and Helge Deller.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Jeroen Roovers <jer@gentoo.org>
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
2013-05-13 22:11:57 +02:00
Alex Elder
638f5abed3 rbd: re-submit flattened write request (part 2)
Add code to rbd_img_obj_exists_callback() to detect when a clone's
parent image has disappeared, and re-submit the original write
request in that case.

Kill off some redundant assertions.

This completes the resolution for:
    http://tracker.ceph.com/issues/3763

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-13 15:06:46 -05:00
Alex Elder
bbea1c1a31 rbd: re-submit write request for flattened clone
Add code to rbd_img_parent_read_full_callback() to detect when a
clone's parent image has disappeared, and re-submit the original
write request in that case.  (See the previous commit for more
reasoning about why this is appropriate.)

Rename some variables in rbd_img_obj_parent_read_full_callback()
to match the convention used in the previous patch.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-13 15:06:45 -05:00
Alex Elder
02c74fbad9 rbd: re-submit read request for flattened clone
If a clone image gets flattened while a parent read request is
underway, the original rbd object request needs to be resubmitted.

The reason is that by the time we get the response to the parent
read request, the data read from the parent may be out of date.
In other words, we could see this sequence of events:

    rbd client                      parent image/osd
    ----------                      ----------------
    original object ENOENT;
        issue parent read
                                    respond to parent read
                                    child image flattened
    original image header refresh
             <--- original object written independently here
    parent read response received

Add code to rbd_img_parent_read_callback() to detect when a clone's
parent image has disappeared (as evidenced by its parent overlap
becoming 0), and re-submit the original read request in that case.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-13 15:06:45 -05:00
Alex Elder
392a9dad7e rbd: detect when clone image is flattened
A format 2 clone image can be the subject of a "flatten" operation,
during which all of its data gets "copied up" from its parent image,
leaving the image fully populated.  Once this is complete, the
clone's association with the parent is abolished.

Since this can occur when a clone is mapped, we need to detect when
it has occurred and handle it accordingly.  We know an image has
been flattened when we know it at one time had a parent, but we have
learned (via a "get_parent" object class method call) it no longer
has one.

There might be in-flight requests at the point we learn an image has
been flattened, so we can't simply clean up parent data structures
right away.  Instead, we'll drop the initial parent reference when
the parent has disappeared (rather than when the image gets
destroyed), which will allow the last in-flight reference to clean
things up when it's complete.

We leverage the fact that a zero parent overlap renders an image
effectively unlayered.  We set the overlap to 0 at the point we
detect the clone image has flattened, which allows the unlayered
behavior to take effect immediately, while keeping other parent
structures in place until in-flight requests to complete.

This and the next few patches resolve:
    http://tracker.ceph.com/issues/3763

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-13 15:06:45 -05:00