Commit Graph

533797 Commits

Author SHA1 Message Date
Andy Lutomirski
36f1a77b3a x86/nmi/64: Make the "NMI executing" variable more consistent
Currently, "NMI executing" is one the first time an outermost
NMI hits repeat_nmi and zero thereafter.  Change it to be zero
each time for consistency.

This is intended to help NMI handling fail harder if it's buggy.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17 12:50:13 +02:00
Andy Lutomirski
23a781e987 x86/nmi/64: Minor asm simplification
Replace LEA; MOV with an equivalent SUB.  This saves one
instruction.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17 12:50:13 +02:00
Andy Lutomirski
810bc075f7 x86/nmi/64: Use DF to avoid userspace RSP confusing nested NMI detection
We have a tricky bug in the nested NMI code: if we see RSP
pointing to the NMI stack on NMI entry from kernel mode, we
assume that we are executing a nested NMI.

This isn't quite true.  A malicious userspace program can point
RSP at the NMI stack, issue SYSCALL, and arrange for an NMI to
happen while RSP is still pointing at the NMI stack.

Fix it with a sneaky trick.  Set DF in the region of code that
the RSP check is intended to detect.  IRET will clear DF
atomically.

( Note: other than paravirt, there's little need for all this
  complexity. We could check RIP instead of RSP. )

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17 12:50:12 +02:00
Andy Lutomirski
a27507ca2d x86/nmi/64: Reorder nested NMI checks
Check the repeat_nmi .. end_repeat_nmi special case first.  The
next patch will rework the RSP check and, as a side effect, the
RSP check will no longer detect repeat_nmi .. end_repeat_nmi, so
we'll need this ordering of the checks.

Note: this is more subtle than it appears.  The check for
repeat_nmi .. end_repeat_nmi jumps straight out of the NMI code
instead of adjusting the "iret" frame to force a repeat.  This
is necessary, because the code between repeat_nmi and
end_repeat_nmi sets "NMI executing" and then writes to the
"iret" frame itself.  If a nested NMI comes in and modifies the
"iret" frame while repeat_nmi is also modifying it, we'll end up
with garbage.  The old code got this right, as does the new
code, but the new code is a bit more explicit.

If we were to move the check right after the "NMI executing"
check, then we'd get it wrong and have random crashes.

( Because the "NMI executing" check would jump to the code that would
  modify the "iret" frame without checking if the interrupted NMI was
  currently modifying it. )

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17 12:50:12 +02:00
Andy Lutomirski
0b22930eba x86/nmi/64: Improve nested NMI comments
I found the nested NMI documentation to be difficult to follow.
Improve the comments.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17 12:50:11 +02:00
Andy Lutomirski
9b6e6a8334 x86/nmi/64: Switch stacks on userspace NMI entry
Returning to userspace is tricky: IRET can fail, and ESPFIX can
rearrange the stack prior to IRET.

The NMI nesting fixup relies on a precise stack layout and
atomic IRET.  Rather than trying to teach the NMI nesting fixup
to handle ESPFIX and failed IRET, punt: run NMIs that came from
user mode on the normal kernel stack.

This will make some nested NMIs visible to C code, but the C
code is okay with that.

As a side effect, this should speed up perf: it eliminates an
RDMSR when NMIs come from user mode.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17 12:50:11 +02:00
Andy Lutomirski
0e181bb581 x86/nmi/64: Remove asm code that saves CR2
Now that do_nmi saves CR2, we don't need to save it in asm.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17 12:50:11 +02:00
Andy Lutomirski
9d05041679 x86/nmi: Enable nested do_nmi() handling for 64-bit kernels
32-bit kernels handle nested NMIs in C.  Enable the exact same
handling on 64-bit kernels as well.  This isn't currently
necessary, but it will become necessary once the asm code starts
allowing limited nesting.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-17 12:50:10 +02:00
Marc Zyngier
591e5bec13 irqchip/gicv3-its: Fix mapping of LPIs to collections
The GICv3 ITS architecture allows a given [DevID, EventID] pair to be
translated to a [LPI, Collection] pair, where DevID is the device writing
the MSI, EventID is the payload being written, LPI is the actual
interrupt number, and Collection is roughly equivalent to a target CPU.

Each LPI can be mapped to a separate collection, but the ITS driver
insists on maintaining the collection on a device basis, instead of doing
it on a per interrupt basis.

This is obviously flawed, and this patch fixes it by adding a per interrupt
index that indicates which collection number is in use.

Reported-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: stable@vger.kernel.org	# 4.1, 4.0
Link: http://lkml.kernel.org/r/1437126402-11677-1-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-17 12:14:29 +02:00
Thomas Gleixner
75a06189fc genirq: Prevent resend to interrupts marked IRQ_NESTED_THREAD
The resend mechanism happily calls the interrupt handler of interrupts
which are marked IRQ_NESTED_THREAD from softirq context. This can
result in crashes because the interrupt handler is not the proper way
to invoke the device handlers. They must be invoked via
handle_nested_irq.

Prevent the resend even if the interrupt has no valid parent irq
set. Its better to have a lost interrupt than a crashing machine.

Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
2015-07-17 11:29:34 +02:00
Jérôme Glisse
e930888487 drm/ttm: improve uncached page deallocation.
Calls to set_memory_wb() incure heavy TLB flush and IPI cost. To
minimize those wait until pool grow beyond batch size before
draining the pool.

Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Reviewed-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Reviewed-and-Tested-by: Michel Dänzer <michel@daenzer.net>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2015-07-17 18:18:04 +10:00
Jérôme Glisse
ef2b731759 drm/ttm: fix uncached page deallocation to properly fill page pool v3.
Current code never allowed the page pool to actualy fill in anyway.
This fix it, so that we only start freeing page from the pool when
we go over the pool size.

Changed since v1:
  - Move the page batching optimization to its separate patch.

Changed since v2:
  - Do not remove code part of the batching optimization with
    this patch.
  - Better commit message.

Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Reviewed-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Reviewed-and-Tested-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2015-07-17 18:17:33 +10:00
Linus Torvalds
21bdb584af Power management and ACPI fixes for v4.2-rc3
- Fix a recently introduced issue in the cpufreq policy object
    reinitialization that leads to CPU offline/online breakage
    (Viresh Kumar).
 
  - Make it possible to access frequency tables of offline CPUs
    which is needed by thermal management code among other things
    (Viresh Kumar).
 
  - Fix an ACPI resource management regression introduced during
    the 4.0 cycle that may cause incorrect resource validation
    results to appear in 32-bit x86 kernels due to silent truncation
    of 64-bit values to 32-bit (Jiang Liu).
 
  - Fix up an RCU-related lockdep complaint about suspicious RCU
    usage in idle caused by using a suspend tracepoint in the
    core suspend-to-idle code (Rafael J Wysocki).
 
 /
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Merge tag 'pm+acpi-4.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management and ACPI fixes from Rafael Wysocki:
 "These fix two bugs in the cpufreq core (including one recent
  regression), fix a 4.0 PCI regression related to the ACPI resources
  management and quieten an RCU-related lockdep complaint about a
  tracepoint in the suspend-to-idle code.

  Specifics:

   - Fix a recently introduced issue in the cpufreq policy object
     reinitialization that leads to CPU offline/online breakage (Viresh
     Kumar)

   - Make it possible to access frequency tables of offline CPUs which
     is needed by thermal management code among other things (Viresh
     Kumar)

   - Fix an ACPI resource management regression introduced during the
     4.0 cycle that may cause incorrect resource validation results to
     appear in 32-bit x86 kernels due to silent truncation of 64-bit
     values to 32-bit (Jiang Liu)

   - Fix up an RCU-related lockdep complaint about suspicious RCU usage
     in idle caused by using a suspend tracepoint in the core suspend-
     to-idle code (Rafael J Wysocki)"

* tag 'pm+acpi-4.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / PCI: Fix regressions caused by resource_size_t overflow with 32-bit kernel
  cpufreq: Allow freq_table to be obtained for offline CPUs
  cpufreq: Initialize the governor again while restoring policy
  suspend-to-idle: Prevent RCU from complaining about tick_freeze()
2015-07-16 21:10:53 -07:00
Linus Torvalds
3e87ee06d0 platform-drivers-x86 for 4.2-3
Fix SMBIOS call handling and hwswitch state coherency in the dell-laptop driver.
 Cleanups for intel_*_ipc drivers.
 
 dell-laptop:
  - Do not cache hwswitch state
  - Check return value of each SMBIOS call
  - Clear buffer before each SMBIOS call
 
 intel_scu_ipc:
  - Move local memory initialization out of a mutex
 
 intel_pmc_ipc:
  - Update kerneldoc formatting
  - Fix compiler casting warnings
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Merge tag 'platform-drivers-x86-v4.2-3' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86

Pull x86 platform driver fixes from Darren Hart:
 "Fix SMBIOS call handling and hwswitch state coherency in the
  dell-laptop driver.  Cleanups for intel_*_ipc drivers.  Details:

  dell-laptop:
   - Do not cache hwswitch state
   - Check return value of each SMBIOS call
   - Clear buffer before each SMBIOS call

  intel_scu_ipc:
   - Move local memory initialization out of a mutex

  intel_pmc_ipc:
   - Update kerneldoc formatting
   - Fix compiler casting warnings"

* tag 'platform-drivers-x86-v4.2-3' of git://git.infradead.org/users/dvhart/linux-platform-drivers-x86:
  intel_scu_ipc: move local memory initialization out of a mutex
  intel_pmc_ipc: Update kerneldoc formatting
  dell-laptop: Do not cache hwswitch state
  dell-laptop: Check return value of each SMBIOS call
  dell-laptop: Clear buffer before each SMBIOS call
  intel_pmc_ipc: Fix compiler casting warnings
2015-07-16 20:57:25 -07:00
Linus Torvalds
f85c712429 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu
Pull m68knommu/coldfire fixes from Greg Ungerer:
 "Contains build fixes and updates for the ColdFire defconfigs.

  Specifically there is a couple of fixes that address problems building
  allnoconfig.  Also fix for enabling PCI bus on the M54xx family of
  ColdFire"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
  m68k: enable PCI support for m5475evb defconfig
  m68k: fix io functions for ColdFire/MMU/PCI case
  m68knommu: update defconfig for ColdFire m5475evb
  m68knommu: update defconfig for ColdFire m5407c3
  m68knommu: update defconfig for ColdFire m5307c3
  m68knommu: update defconfig for ColdFire m5275evb
  m68knommu: update defconfig for ColdFire m5272c3
  m68knommu: update defconfig for ColdFire m5249evb
  m68knommu: update defconfig for m5208evb
  m68knommu: make ColdFire SoC selection a choice
  m68knommu: improve the clock configuration defaults
  m68knommu: force setting of CONFIG_CLOCK_FREQ for ColdFire
2015-07-16 20:49:09 -07:00
Mike Snitzer
665022d72f dm cache: avoid calls to prealloc_free_structs() if possible
If no work was performed then prealloc_data_structs() wasn't ever called
so there isn't any need to call prealloc_free_structs().

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-07-16 22:32:08 -04:00
Mike Snitzer
e782eff591 dm cache: avoid preallocation if no work in writeback_some_dirty_blocks()
Refactor writeback_some_dirty_blocks() to avoid prealloc_data_structs()
if the policy doesn't have any dirty blocks ready for writeback.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-07-16 22:32:07 -04:00
Mike Snitzer
386cb7cdee dm cache: do not wake_worker() in free_migration()
All methods that queue work call wake_worker() as you'd expect.
E.g. cell_defer, defer_bio, quiesce_migration (which is called by
writeback, promote, demote_then_promote, invalidate, discard, etc).

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-07-16 22:32:06 -04:00
Dave Airlie
aaab3bbab8 Merge branch 'drm-rockchip-2015-07-13' of https://github.com/markyzq/kernel-drm-rockchip into drm-fixes
misc rockchip fixes.

* 'drm-rockchip-2015-07-13' of https://github.com/markyzq/kernel-drm-rockchip:
  drm/rockchip: vop: remove hardware cursor window
  drm/rockchip: vop: switch cursor plane to window 3
  drm/rockchip: Drop owner assignment from platform_driver
  drm/rockchip: use drm_gem_mmap helpers
  drm/rockchip: only call drm_fb_helper_hotplug_event if fb_helper present
  drm/rockchip: Add BGR formats to VOP
2015-07-17 10:25:02 +10:00
Dave Airlie
e1e50e1e1e imx-drm: fixes for parallel-display, imx-tve, and ipu-common
These patches fix the parallel-display driver to use the standard OF
 graph bindings for connecting a drm_panel via device tree instead of
 an undocumented, driver specific device tree property, take care to
 disable all IPU interrupts before setting up the irq chip to fix a
 kexec lockup, and fix VGA output on i.MX53-QSB boards by correcting
 the media bus format set by the imx-tve driver.
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Merge tag 'imx-drm-fixes-2015-07-14' of git://git.pengutronix.de/git/pza/linux into drm-fixes

imx-drm: fixes for parallel-display, imx-tve, and ipu-common

These patches fix the parallel-display driver to use the standard OF
graph bindings for connecting a drm_panel via device tree instead of
an undocumented, driver specific device tree property, take care to
disable all IPU interrupts before setting up the irq chip to fix a
kexec lockup, and fix VGA output on i.MX53-QSB boards by correcting
the media bus format set by the imx-tve driver.

* tag 'imx-drm-fixes-2015-07-14' of git://git.pengutronix.de/git/pza/linux:
  drm/imx: tve: fix media bus format for VGA output
  GPU: ipu: fix lockup caused by pending chained interrupts
  drm/imx: parallel-display: fix drm_panel support
2015-07-17 10:24:34 +10:00
Dave Airlie
8f6644ca97 Merge branch 'drm-armada-fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm into drm-fixes
A range of fixes for the Armada DRM driver:
- A missing wakeup could result in overlay frames being delayed, causing
  video playback to hiccup.
- Avoid unmapping a dma-buf attachment which was never mapped
- Fix the overlay when partially off the screen by switching to the
  drm_plane_helper_check_update() helper and using the calculated
  coordinates to set the start address.
- Remove an incorrect assignment to crtc->mode - which should be the
  unadjusted mode.
- Fix a missing call to drm_plane_cleanup() in the overlay code.

* 'drm-armada-fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
  drm/armada: avoid saving the adjusted mode to crtc->mode
  drm/armada: fix overlay when partially off-screen
  drm/armada: convert overlay to use drm_plane_helper_check_update()
  drm/armada: fix gem object free after failed prime import
  drm/armada: fix incorrect overlay plane cleanup
  drm/armada: fix missing overlay wake-up
2015-07-17 10:06:04 +10:00
Dave Airlie
61f2669fce Merge tag 'drm-intel-fixes-2015-07-15' of git://anongit.freedesktop.org/drm-intel into drm-fixes
Next batch of i915 fixes. Note that the compat32 patch here needs the drm
core one to be actually useful, I'll send you that one with a separate
drm-fixes pull request. One revert because a fix in -rc2 did break
existing userspace.

* tag 'drm-intel-fixes-2015-07-15' of git://anongit.freedesktop.org/drm-intel:
  drm/i915: Do not call intel_crtc_disable if the crtc is already disabled.
  Revert "drm/i915: Declare the swizzling unknown for L-shaped configurations"
  drm/i915: Forward all core DRM ioctls to core compat handling
  drm/i915: fix oops in primary_check_plane
  drm/i915: remove unused has_dma_mapping flag
  drm/i915: Fix missing return warning for !CONFIG_DEBUGFS
  drm/i915: avoid leaking DMA mappings
  drm/i915: Snapshot seqno of most recently submitted request.
  drm/i915: Store device pointer in contexts for late tracepoint usafe
2015-07-17 09:57:16 +10:00
Dave Airlie
375539832c Merge tag 'topic/drm-fixes-2015-07-16' of git://anongit.freedesktop.org/drm-intel into drm-fixes
Ok next attempt at drm-fixes pull. Big thing really is just the compat32
one for addfb2.1.

* tag 'topic/drm-fixes-2015-07-16' of git://anongit.freedesktop.org/drm-intel:
  drm: Provide compat ioctl for addfb2.1
  Documentation: drm: Fix tablulation in KMS properties table
  drm: add a check for x/y in drm_mode_setcrtc
  drm/rockchip: use drm_gem_mmap helpers
2015-07-17 09:56:00 +10:00
Dave Airlie
90438ac813 Merge branch 'drm-fixes-4.2' of git://people.freedesktop.org/~agd5f/linux into drm-fixes
More radeon and amdgpu fixes for 4.2.  Mostly amdgpu bug fixes.

* 'drm-fixes-4.2' of git://people.freedesktop.org/~agd5f/linux:
  drm/amdgpu/dce8: Re-set VBLANK interrupt state when enabling a CRTC
  drm/radeon/ci: silence a harmless PCC warning
  drm/amdgpu/cz: silence some dpm debug output
  drm/amdgpu/cz: store the forced dpm level
  drm/amdgpu/cz: unforce dpm levels before forcing to low/high
  drm/amdgpu: remove bogus check in gfx8 rb setup
  drm/amdgpu: set proper index/data pair for smc regs on CZ (v2)
  drm/amdgpu: disable the IP module if early_init returns -ENOENT (v2)
  drm/amdgpu: stop context leak in the error path
  drm/amdgpu: validate the context id in the dependencies
  drm/radeon: fix user ptr race condition
  drm/radeon: Don't flush the GART TLB if rdev->gart.ptr == NULL
  drm/radeon: add a dpm quirk for Sapphire Radeon R9 270X 2GB GDDR5
2015-07-17 09:39:23 +10:00
Linus Torvalds
761ab7664b Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
 "A collection of fixes from the last few weeks that should go into the
  current series.  This contains:

   - Various fixes for the per-blkcg policy data, fixing regressions
     since 4.1.  From Arianna and Tejun

   - Code cleanup for bcache closure macros from me.  Really just
     flushing this out, it's been sitting in another branch for months

   - FIELD_SIZEOF cleanup from Maninder Singh

   - bio integrity oops fix from Mike

   - Timeout regression fix for blk-mq from Ming Lei"

* 'for-linus' of git://git.kernel.dk/linux-block:
  blk-mq: set default timeout as 30 seconds
  NVMe: Reread partitions on metadata formats
  bcache: don't embed 'return' statements in closure macros
  blkcg: fix blkcg_policy_data allocation bug
  blkcg: implement all_blkcgs list
  blkcg: blkcg_css_alloc() should grab blkcg_pol_mutex while iterating blkcg_policy[]
  blkcg: allow blkcg_pol_mutex to be grabbed from cgroup [file] methods
  block/blk-cgroup.c: free per-blkcg data when freeing the blkcg
  block: use FIELD_SIZEOF to calculate size of a field
  bio integrity: do not assume bio_integrity_pool exists if bioset exists
2015-07-16 16:38:08 -07:00
Linus Torvalds
f76d94def5 A couple trivial fixes and an error path fix
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Merge tag 'jfs-4.2' of git://github.com/kleikamp/linux-shaggy

Pull jfs fixes from David Kleikamp:
 "A couple trivial fixes and an error path fix"

* tag 'jfs-4.2' of git://github.com/kleikamp/linux-shaggy:
  jfs: clean up jfs_rename and fix out of order unlock
  jfs: fix indentation on if statement
  jfs: removed a prohibited space after opening parenthesis
2015-07-16 16:28:28 -07:00
Murali Karicheri
8b4769cc53 ARM: keystone: dts: rename pcie nodes to help override status
Now that PCIe DT binding is disabled in SoC specific DTS,
we need a way to override it in a board specific DTS. So
rename the PCIe nodes accordingly.

Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>
2015-07-16 18:13:03 -04:00
Murali Karicheri
9dd4f28f36 ARM: keystone: dts: fix dt bindings for PCIe
Currently PCIe DT bindings are broken. PCIe driver can't function
without having a SerDes driver that provide the phy configuration.
On K2E EVM, this causes problem since the EVM has Marvell SATA
controller present and with default values in the SerDes register,
it seems to pass the PCIe link check, but causes issues since
the configuration is not correct. The manifestation is that when
EVM is booted with NFS rootfs, the boot hangs. We shouldn't enable
PCIe on this EVM since to work, SerDes driver has to be present as
well. So by default, the PCIe DT binding should be disabled in SoC
specific DTS. It can be enabled in the board specific DTS when the
SerDes device driver is also present.

So fix the status of PCIe DT bindings in the SoC specific DTS to
"disabled". To enable PCIe, the status should be set to "ok" in
the EVM DTS file when SerDes driver support becomes available in
the upstream tree.

Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>
2015-07-16 18:12:57 -04:00
Rafael J. Wysocki
17ffc8b083 Merge branches 'pm-cpuidle', 'pm-cpufreq' and 'acpi-resources'
* pm-cpuidle:
  suspend-to-idle: Prevent RCU from complaining about tick_freeze()

* pm-cpufreq:
  cpufreq: Allow freq_table to be obtained for offline CPUs
  cpufreq: Initialize the governor again while restoring policy

* acpi-resources:
  ACPI / PCI: Fix regressions caused by resource_size_t overflow with 32-bit kernel
2015-07-16 23:47:19 +02:00
Robert Jarzmik
a927ef895e ARM: pxa: fix dm9000 platform data regression
Since dm9000 driver added support for a vcc regulator, platform data
based platforms have their ethernet broken, as the regulator claiming
returns -EPROBE_DEFER and prevents dm9000 loading.

This patch fixes this for all pxa boards using dm9000, by using the
specific regulator_has_full_constraints() function.

This was discovered and tested on the cm-x300 board.

Fixes: 7994fe55a4 ("dm9000: Add regulator and reset support to dm9000")
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Igor Grinberg <grinberg@compulab.co.il>
2015-07-16 22:43:59 +02:00
Michel Dänzer
1002d71841 drm/amdgpu/dce8: Re-set VBLANK interrupt state when enabling a CRTC
Something (ATOM BIOS?) seems to be clobbering the LB_INTERRUPT_MASK
register while the CRTC is off, which caused e.g. glxgears or
gnome-shell to hang after a modeset.

Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Jammy Zhou <Jammy.Zhou@amd.com>
2015-07-16 12:39:44 -04:00
Alex Deucher
bda5e3e97f drm/radeon/ci: silence a harmless PCC warning
This has been a source of confusion.  Make it debug only.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
2015-07-16 12:39:43 -04:00
Alex Deucher
1a45e8a11b drm/amdgpu/cz: silence some dpm debug output
Reviewed-by: Jammy Zhou <Jammy.Zhou@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2015-07-16 12:39:43 -04:00
Alex Deucher
58829aa67d drm/amdgpu/cz: store the forced dpm level
So the selected forced level shows up properly in sysfs.

Reviewed-by: Jammy Zhou <Jammy.Zhou@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2015-07-16 12:39:42 -04:00
Alex Deucher
85cfe09655 drm/amdgpu/cz: unforce dpm levels before forcing to low/high
This is necessary to properly reset the min/max limits before
clamping them otherwise we may get improper clamping depending
on what what was the last forced level.

Reviewed-by: Jammy Zhou <Jammy.Zhou@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2015-07-16 12:39:41 -04:00
Alex Deucher
4f2d3ad686 drm/amdgpu: remove bogus check in gfx8 rb setup
Always respect the harvest configuration as is.

Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2015-07-16 12:39:41 -04:00
Alex Deucher
7b92cdbfe2 drm/amdgpu: set proper index/data pair for smc regs on CZ (v2)
v2: squash in later fix

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2015-07-16 12:39:40 -04:00
Alex Deucher
974e6b641f drm/amdgpu: disable the IP module if early_init returns -ENOENT (v2)
If we run into a part with a harvest configuration where the entire
IP block is unusable, just disable the IP block.

v2: fix logic as noted by Christian

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2015-07-16 12:39:39 -04:00
Christian König
5c2327beed drm/amdgpu: stop context leak in the error path
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Jammy Zhou <Jammy.Zhou@amd.com>
2015-07-16 12:39:39 -04:00
Christian König
76a1ea618f drm/amdgpu: validate the context id in the dependencies
Just to make sure userspace don't send nonsense to the kernel.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Jammy Zhou <Jammy.Zhou@amd.com>
2015-07-16 12:39:38 -04:00
Christian König
12f1384da6 drm/radeon: fix user ptr race condition
Port of amdgpu patch 9298e52f8b.

Signed-off-by: Christian König <christian.koenig@amd.com>
CC: stable@vger.kernel.org
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2015-07-16 12:39:37 -04:00
Michel Dänzer
233709d2cd drm/radeon: Don't flush the GART TLB if rdev->gart.ptr == NULL
This can be the case when the GPU is powered off, e.g. via vgaswitcheroo
or runpm. When the GPU is powered up again, radeon_gart_table_vram_pin
flushes the TLB after setting rdev->gart.ptr to non-NULL.

Fixes panic on powering off R7xx GPUs.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61529
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
2015-07-16 12:39:37 -04:00
Alex Deucher
5dfc71bc44 drm/radeon: add a dpm quirk for Sapphire Radeon R9 270X 2GB GDDR5
bug:
https://bugs.freedesktop.org/show_bug.cgi?id=76490

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
2015-07-16 12:39:36 -04:00
Ming Lei
e56f698bd0 blk-mq: set default timeout as 30 seconds
It is reasonable to set default timeout of request as 30 seconds instead of
30000 ticks, which may be 300 seconds if HZ is 100, for example, some arm64
based systems may choose 100 HZ.

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Fixes: c76cbbcf40 ("blk-mq: put blk_queue_rq_timeout together in blk_mq_init_queue()"
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-07-16 08:39:11 -06:00
Mike Snitzer
255eac2005 dm cache: display 'needs_check' in status if it is set
There is currently no way to see that the needs_check flag has been set
in the metadata.  Display 'needs_check' in the cache status if it is set
in the cache metadata.

Also, update cache documentation.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-07-16 10:23:50 -04:00
Mike Snitzer
e4c78e210d dm thin: display 'needs_check' in status if it is set
There is currently no way to see that the needs_check flag has been set
in the metadata.  Display 'needs_check' in the thin-pool status if it is
set in the thinp metadata.

Also, update thinp documentation.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-07-16 10:23:50 -04:00
Mike Snitzer
bcc696fac1 dm thin: stay in out-of-data-space mode once no_space_timeout expires
This fixes an issue where running out of data space would cause the
thin-pool's metadata to become read-only.  There was no reason to make
metadata read-only -- calling set_pool_mode() with PM_READ_ONLY was a
misguided way to error all queued and future write IOs.  We can
accomplish the same by degrading from PM_OUT_OF_DATA_SPACE to
PM_OUT_OF_DATA_SPACE with error_if_no_space enabled.

Otherwise, the use of PM_READ_ONLY could cause a race where commit() was
started before the PM_READ_ONLY transition but dm_pool_commit_metadata()
would go on to fail because the block manager had transitioned to
read-only.  The return of -EPERM from dm_pool_commit_metadata(), due to
attempting to commit while in read-only mode, caused the thin-pool to
set 'needs_check' because a metadata_operation_failed().  This needless
cascade of failures makes life for users more difficult than needed.

Reported-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-07-16 10:23:49 -04:00
Jens Axboe
1278dd6809 scsi: fix host max depth checking for the 'queue_depth' sysfs interface
Commit 1e6f241604 changed the scsi sysfs 'queue_depth' code to
rejects depths higher than the scsi host template setting. But lots
of hosts set this to 1, and update the settings in the scsi host
when the controller/devices probing happens.

This breaks (at least) mpt2sas and mpt3sas runtime setting of queue
depth, returning EINVAL for all settings but '1'. And once it's set to
1, there's no way to go back up.

Cc: stable@vger.kernel.org
Fixes: 1e6f241604 "scsi: don't allow setting of queue_depth bigger than can_queue"
Signed-off-by: Jens Axboe <axboe@fb.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-07-16 16:09:53 +03:00
Grygorii Strashko
fdd50409c8 gpio: pca953x: fix nested irqs rescheduling
pca953x interrupt controller functionality is implemented using
nested threaded IRQs which require parent_irq to be configured
properly otherwise below warning can be seen if IRQ core
will try re-schedule nested IRQ:

------------[ cut here ]------------
WARNING: CPU: 1 PID: 12 at kernel/irq/manage.c:696 irq_nested_primary_handler+0x30/0x38()
Primary handler called for nested irq 301
Modules linked in: uinput ipv6 smsc95xx usbnet mii imx2_wdt etnaviv(C) matrix_keypad matrix_keymap ar1021_i2c
CPU: 1 PID: 12 Comm: ksoftirqd/1 Tainted: G        WC    4.1.1 #9
Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
Backtrace:
[<c0013298>] (dump_backtrace) from [<c0013488>] (show_stack+0x20/0x24)
[<c0013468>] (show_stack) from [<c05743c4>] (dump_stack+0x70/0xc0)
[<c0574354>] (dump_stack) from [<c002b7b8>] (warn_slowpath_common+0x88/0xc0)
[<c002b730>] (warn_slowpath_common) from [<c002b8ac>] (warn_slowpath_fmt+0x40/0x48)
[<c002b870>] (warn_slowpath_fmt) from [<c0075798>] (irq_nested_primary_handler+0x30/0x38)
[<c0075768>] (irq_nested_primary_handler) from [<c0075200>] (handle_irq_event_percpu+0x70/0x2d0)
[<c0075190>] (handle_irq_event_percpu) from [<c00754ac>] (handle_irq_event+0x4c/0x6c)
[<c0075460>] (handle_irq_event) from [<c0078204>] (handle_simple_irq+0xa4/0xc8)
[<c0078160>] (handle_simple_irq) from [<c0077cd4>] (resend_irqs+0x50/0x7c)
[<c0077c84>] (resend_irqs) from [<c002f99c>] (tasklet_action+0x94/0x140)
[<c002f908>] (tasklet_action) from [<c002eea8>] (__do_softirq+0xa0/0x3c8)
[<c002ee08>] (__do_softirq) from [<c002f208>] (run_ksoftirqd+0x38/0x54)
[<c002f1d0>] (run_ksoftirqd) from [<c004b1e4>] (smpboot_thread_fn+0x1f8/0x2f0)
[<c004afec>] (smpboot_thread_fn) from [<c0047744>] (kthread+0xe8/0x104)
[<c004765c>] (kthread) from [<c000fac8>] (ret_from_fork+0x14/0x2c)
---[ end trace 96052cda48865769 ]---

The issue was reported and described in details by Lothar Waßmann and
Christian Gmeiner in https://lkml.org/lkml/2014/9/9/123.

Fix it by adding missed call of gpiochip_set_chained_irqchip()
so GPIO IRQ chip helpers will set parent_irq for nested IRQs
properly.

Reported-by: Lothar Waßmann <LW@KARO-electronics.de>
Tested-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-07-16 14:40:08 +02:00
Seymour, Shane M
e7ac6c6666 st: null pointer dereference panic caused by use after kref_put by st_open
Two SLES11 SP3 servers encountered similar crashes simultaneously
following some kind of SAN/tape target issue:

...
qla2xxx [0000:81:00.0]-801c:3: Abort command issued nexus=3:0:2 --  1 2002.
qla2xxx [0000:81:00.0]-801c:3: Abort command issued nexus=3:0:2 --  1 2002.
qla2xxx [0000:81:00.0]-8009:3: DEVICE RESET ISSUED nexus=3:0:2 cmd=ffff882f89c2c7c0.
qla2xxx [0000:81:00.0]-800c:3: do_reset failed for cmd=ffff882f89c2c7c0.
qla2xxx [0000:81:00.0]-800f:3: DEVICE RESET FAILED: Task management failed nexus=3:0:2 cmd=ffff882f89c2c7c0.
qla2xxx [0000:81:00.0]-8009:3: TARGET RESET ISSUED nexus=3:0:2 cmd=ffff882f89c2c7c0.
qla2xxx [0000:81:00.0]-800c:3: do_reset failed for cmd=ffff882f89c2c7c0.
qla2xxx [0000:81:00.0]-800f:3: TARGET RESET FAILED: Task management failed nexus=3:0:2 cmd=ffff882f89c2c7c0.
qla2xxx [0000:81:00.0]-8012:3: BUS RESET ISSUED nexus=3:0:2.
qla2xxx [0000:81:00.0]-802b:3: BUS RESET SUCCEEDED nexus=3:0:2.
qla2xxx [0000:81:00.0]-505f:3: Link is operational (8 Gbps).
qla2xxx [0000:81:00.0]-8018:3: ADAPTER RESET ISSUED nexus=3:0:2.
qla2xxx [0000:81:00.0]-00af:3: Performing ISP error recovery - ha=ffff88bf04d18000.
 rport-3:0-0: blocked FC remote port time out: removing target and saving binding
qla2xxx [0000:81:00.0]-505f:3: Link is operational (8 Gbps).
qla2xxx [0000:81:00.0]-8017:3: ADAPTER RESET SUCCEEDED nexus=3:0:2.
 rport-2:0-0: blocked FC remote port time out: removing target and saving binding
sg_rq_end_io: device detached
BUG: unable to handle kernel NULL pointer dereference at 00000000000002a8
IP: [<ffffffff8133b268>] __pm_runtime_idle+0x28/0x90
PGD 7e6586f067 PUD 7e5af06067 PMD 0 [1739975.390354] Oops: 0002 [#1] SMP
CPU 0
...
Supported: No, Proprietary modules are loaded [1739975.390463]
Pid: 27965, comm: ABCD Tainted: PF           X 3.0.101-0.29-default #1 HP ProLiant DL580 Gen8
RIP: 0010:[<ffffffff8133b268>]  [<ffffffff8133b268>] __pm_runtime_idle+0x28/0x90
RSP: 0018:ffff8839dc1e7c68  EFLAGS: 00010202
RAX: 0000000000000000 RBX: ffff883f0592fc00 RCX: 0000000000000090
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000138
RBP: 0000000000000138 R08: 0000000000000010 R09: ffffffff81bd39d0
R10: 00000000000009c0 R11: ffffffff81025790 R12: 0000000000000001
R13: ffff883022212b80 R14: 0000000000000004 R15: ffff883022212b80
FS:  00007f8e54560720(0000) GS:ffff88407f800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 00000000000002a8 CR3: 0000007e6ced6000 CR4: 00000000001407f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process ABCD (pid: 27965, threadinfo ffff8839dc1e6000, task ffff883592e0c640)
Stack:
 ffff883f0592fc00 00000000fffffffa 0000000000000001 ffff883022212b80
 ffff883eff772400 ffffffffa03fa309 0000000000000000 0000000000000000
 ffffffffa04003a0 ffff883f063196c0 ffff887f0379a930 ffffffff8115ea1e
Call Trace:
 [<ffffffffa03fa309>] st_open+0x129/0x240 [st]
 [<ffffffff8115ea1e>] chrdev_open+0x13e/0x200
 [<ffffffff811588a8>] __dentry_open+0x198/0x310
 [<ffffffff81167d74>] do_last+0x1f4/0x800
 [<ffffffff81168fe9>] path_openat+0xd9/0x420
 [<ffffffff8116946c>] do_filp_open+0x4c/0xc0
 [<ffffffff8115a00f>] do_sys_open+0x17f/0x250
 [<ffffffff81468d92>] system_call_fastpath+0x16/0x1b
 [<00007f8e4f617fd0>] 0x7f8e4f617fcf
Code: eb d3 90 48 83 ec 28 40 f6 c6 04 48 89 6c 24 08 4c 89 74 24 20 48 89 fd 48 89 1c 24 4c 89 64 24 10 41 89 f6 4c 89 6c 24 18 74 11 <f0> ff 8f 70 01 00 00 0f 94 c0 45 31 ed 84 c0 74 2b 4c 8d a5 a0
RIP  [<ffffffff8133b268>] __pm_runtime_idle+0x28/0x90
 RSP <ffff8839dc1e7c68>
CR2: 00000000000002a8

Analysis reveals the cause of the crash to be due to STp->device
being NULL. The pointer was NULLed via scsi_tape_put(STp) when it
calls scsi_tape_release(). In st_open() we jump to err_out after
scsi_block_when_processing_errors() completes and returns the
device as offline (sdev_state was SDEV_DEL):

1180 /* Open the device. Needs to take the BKL only because of incrementing the SCSI host
1181    module count. */
1182 static int st_open(struct inode *inode, struct file *filp)
1183 {
1184         int i, retval = (-EIO);
1185         int resumed = 0;
1186         struct scsi_tape *STp;
1187         struct st_partstat *STps;
1188         int dev = TAPE_NR(inode);
1189         char *name;
...
1217         if (scsi_autopm_get_device(STp->device) < 0) {
1218                 retval = -EIO;
1219                 goto err_out;
1220         }
1221         resumed = 1;
1222         if (!scsi_block_when_processing_errors(STp->device)) {
1223                 retval = (-ENXIO);
1224                 goto err_out;
1225         }
...
1264  err_out:
1265         normalize_buffer(STp->buffer);
1266         spin_lock(&st_use_lock);
1267         STp->in_use = 0;
1268         spin_unlock(&st_use_lock);
1269         scsi_tape_put(STp); <-- STp->device = 0 after this
1270         if (resumed)
1271                 scsi_autopm_put_device(STp->device);
1272         return retval;

The ref count for the struct scsi_tape had already been reduced
to 1 when the .remove method of the st module had been called.
The kref_put() in scsi_tape_put() caused scsi_tape_release()
to be called:

0266 static void scsi_tape_put(struct scsi_tape *STp)
0267 {
0268         struct scsi_device *sdev = STp->device;
0269
0270         mutex_lock(&st_ref_mutex);
0271         kref_put(&STp->kref, scsi_tape_release); <-- calls this
0272         scsi_device_put(sdev);
0273         mutex_unlock(&st_ref_mutex);
0274 }

In scsi_tape_release() the struct scsi_device in the struct
scsi_tape gets set to NULL:

4273 static void scsi_tape_release(struct kref *kref)
4274 {
4275         struct scsi_tape *tpnt = to_scsi_tape(kref);
4276         struct gendisk *disk = tpnt->disk;
4277
4278         tpnt->device = NULL; <<<---- where the dev is nulled
4279
4280         if (tpnt->buffer) {
4281                 normalize_buffer(tpnt->buffer);
4282                 kfree(tpnt->buffer->reserved_pages);
4283                 kfree(tpnt->buffer);
4284         }
4285
4286         disk->private_data = NULL;
4287         put_disk(disk);
4288         kfree(tpnt);
4289         return;
4290 }

Although the problem was reported on SLES11.3 the problem appears
in linux-next as well.

The crash is fixed by reordering the code so we no longer access
the struct scsi_tape after the kref_put() is done on it in st_open().

Signed-off-by: Shane Seymour <shane.seymour@hp.com>
Signed-off-by: Darren Lavender <darren.lavender@hp.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.com>
Acked-by: Kai Mäkisara <kai.makisara@kolumbus.fi>
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-07-16 15:32:32 +03:00