ptrace_{get,set}_watch_regs access current_cpu_data to get the watch
register count/masks, which calls smp_processor_id(). However they are
run in preemptible context and therefore trigger warnings like so:

[ 6340.092000] BUG: using smp_processor_id() in preemptible [00000000] code: gdb/367
[ 6340.092000] caller is ptrace_get_watch_regs+0x44/0x220

Since the watch register count/masks should be the same across all
CPUs, use boot_cpu_data instead. Note that this may need to change in
future should a heterogenous system be supported where the count/masks
are not the same across all CPUs (the current code is also incorrect
for this scenario - current_cpu_data here would not necessarily be
correct for the CPU that the target task will execute on).
Signed-off-by: NAlex Smith <alex.smith@imgtec.com>
Reviewed-by: NPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6879/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The lock is taken in the raw irq path and therefore a rawlock should be
used instead of a normal spinlock.
While here I drop the export symbol on that variable since there are no
other users.
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: linux-mips@linux-mips.org
Cc: Hua Yan <yanh@lemote.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Alex Smith <alex.smith@imgtec.com>
Cc: Hongliang Tao <taohl@lemote.com>
Cc: Wu Zhangjin <wuzhangjin@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/6936/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

A kernel build with binutils 2.24 is going to emit warnings like

  CC      kernel/sys.o
{standard input}: Assembler messages:
{standard input}:701: Warning: the 32-bit MIPS architecture does not support the `mdmx' extension
{standard input}:701: Warning: the `mdmx' extension requires 64-bit FPRs
{standard input}:701: Warning: the `mips3d' extension requires MIPS32 revision 2 or greater
{standard input}:701: Warning: the `mips3d' extension requires 64-bit FPRs

for almost every file.  This is caused by changes to gas' interpretation
of .set semantics.  Fixed by explicitly disabling MIPS3D and MDMX for
Sibyte builds.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The parent field of the 'rc32434_res_pci_mem1' resource points to
the resource itself which is obviously wrong. Due to the broken
initialitazion, the PCI devices on the Mikrotik RB532 boards are
not working since commit 22283178 (MIPS: avoid possible resource
conflict in register_pci_controller).

Remove the field initialization to fix the issue.
Signed-off-by: NGabor Juhos <juhosg@openwrt.org>
Reported-by: NWaldemar Brodkorb <wbx@openadk.org>
Cc: linux-mips@linux-mips.org
Cc: Gabor Juhos <juhosg@openwrt.org>
Patchwork: https://patchwork.linux-mips.org/patch/6940/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

If the 'memsize' environmental variable is not set by the bootloader
the 'memsize' variable is not initialized, leading to potential memory
problems. This patch fixes the problem by setting the initial
value to '0' to force the kernel to set a good default memory size.

Cc: <stable@vger.kernel.org> # v3.15+
Reported-by: NMatheus Almeida <Matheus.Almeida@imgtec.com>
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: stable@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/6984/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Introduced by the following two commits:
75b5b5e0
"MIPS: Add support for FTLBs"
6de20451
"MIPS: Add printing of ES bit for Imgtec cores when cache error occurs"
Signed-off-by: NMarkos Chandras <markos.chandras@imgtec.com>
Reported-by: NMatheus Almeida <Matheus.Almeida@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: stable@vger.kernel.org # v3.14+
Patchwork: https://patchwork.linux-mips.org/patch/6980/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Originally, __NR_O32_Linux_syscalls, __NR_N32_Linux_syscalls and
__NR_64_Linux_syscalls have the same values as __NR_Linux_syscalls in
corresponding ABIs. But after commit 367f0b50 (MIPS: Wire up
renameat2 syscall) they are not the same. I think this is incorrect and
need a fix.
Signed-off-by: NHuacai Chen <chenhc@lemote.com>
Cc: John Crispin <john@phrozen.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/6987/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Two issues:

  o For beql_op, beql_op, bne_op, bnel_op, blez_op, blezl_op, bgtz_op and
    bgtzl_op the wrong field was being checked for the instruction opcode.
  o For blez_op / blezl_op and bgtz_op / bgtzl_op the test was testing
    for the wrong opcode.

This bug got introduced by d8d4e3ae [MIPS
Kprobes: Refactor branch emulation].
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
Acked-by: NLeonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Acked-by: NVictor Kamensky <kamensky@cisco.com>

Missing a "|" in AUDIT_ARCH_MIPSEL64N32 macro definition.
Signed-off-by: NHuacai Chen <chenhc@lemote.com>
Reviewed-by: NMarkos Chandras <markos.chandras@imgtec.com>
Cc: John Crispin <john@phrozen.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/6978/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

asid_cache must be unsigned long otherwise on 64 bit systems it will
become 0 if the value in get_new_mmu_context() reaches 0xffffffff and
in the end the assumption of ASID_FIRST_VERSION is not true anymore
thus leads to more dangerous things.

Initial patch by Yong Zhang <yong.zhang@windriver.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
Reported-by: Nlibin <huawei.libin@huawei.com>

Pull sound fixes from Takashi Iwai:
 "Unfortunately this update became bigger than previous pull requests,
  which is almost a pattern in rc5-6.  But, the only obvious big changes
  are for the new Intel DSP ASoC drivers, so the impact must be fairly
  limited.

  Other than that, usual small fixes in various fields: HD-audio, ASoC
  core and ASoC fsl and codec drivers"

* tag 'sound-3.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (26 commits)
  ALSA: sb_mixer: missing return statement
  ASoC: wm8962: Update register CLASS_D_CONTROL_1 to be non-volatile
  ASoC: Intel: Fix Baytrail SST DSP firmware loading
  ALSA: hda - mask buggy stream DMA0 for Broadwell display controller
  ALSA: hda - Add new GPU codec ID to snd-hda
  ASoC: fsl_esai: Set PCRC and PRRC registers at the end of hw_params()
  ASoC: fsl_esai: Only bypass sck_div for EXTAL source
  ASoC: fsl_esai: Fix incorrect condition within ratio range check for FP
  ASoC: dapm: Fix SUSPEND -> OFF bias sequence
  ASoC: dapm: Skip CODEC<->CODEC links in connect_dai_link_widgets()
  ASoC: pcm: Fix incorrect condition check for case SNDRV_PCM_TRIGGER_SUSPEND
  ALSA: hda - add headset mic detect quirks for three Dell laptops
  ASoC: Update Cirrus Logic CODEC maintainers.
  ASoC: Intel: Fix block offset calculations.
  ASoC: Intel: Fix check for pdata usage before dereference.
  ASoC: Intel: Fix stream position pointer.
  ASoC: Intel: Fix allow hw_params to be called more than once.
  ASoC: Intel: Fix Audio DSP usage when IOMMU is enabled.
  ASoC: Intel: Fix Haswell/Broadwell DSP page table creation.
  ASoC: Intel: Fix allocated block list usage when adding blocks.
  ...

Pull MIPS fixes from Ralf Baechle:
 "MIPS fixes for various loose ends:

   - Fix workarounds for R4000 erratum.
   - Patch up DEC, Siemens-Nixdorf and Loongson hardware support.
   - Wire up renameat2 syscall.
   - Delete unused file - it was causing false warnings from maintenance
     scripts.
   - Revert a patch because it's functionality is now implemented twice
     which causes superfluous /proc/cpuinfo output.
   - Fix a microMIPS regression"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: mm: Fix broken microMIPS kernel regression.
  MIPS: Add new AUDIT_ARCH token for the N32 ABI on MIPS64
  MIPS: Wire up renameat2 syscall.
  MIPS: inst.h: Rename BITFIELD_FIELD to __BITFIELD_FIELD.
  MIPS: Remove file missed when removing rm9k support a while ago.
  MIPS/loongson2_cpufreq: Fix CPU clock rate setting
  MIPS: Loongson: No need to select GENERIC_HARDIRQS_NO__DO_IRQ
  MIPS: csum_partial.S CPU_DADDI_WORKAROUNDS bug fix
  MIPS: __strncpy_from_user_asm CPU_DADDI_WORKAROUNDS bug fix
  MIPS: __delay CPU_DADDI_WORKAROUNDS bug fix
  MIPS: DEC/SNI: O32 wrapper stack switching fixes
  MIPS: DEC: Bus error handler <asm/cpu-type.h> fixes
  MAINTAINERS: TURBOchannel: Update entry
  Revert "MIPS: MT: proc: Add support for printing VPE and TC ids"

Pull parisc fixes from Helge Deller:
 "There are two patches in here:

  The first patch greatly improves latency and corrects the memory
  ordering in our light-weight atomic locking syscall.

  The second patch ratelimits printing of userspace segfaults in the
  same way as it's done on other platforms.  This fixes a possible DOS
  on parisc since it prevents the syslog to grow too fast.  For example,
  when the debian acl2 package was built on our debian buildd servers,
  this package produced lots of gigabytes in syslog in very short time
  and thus filled our harddisks, which then turned the server nearly
  completely unaccessible and unresponsive"

* 'parisc-3.15-4' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Improve LWS-CAS performance
  parisc: ratelimit userspace segfault printing

Pull two arm64 fixes from Catalin Marinas:
 - arm64 migrate_irqs() fix following commit ffde1de6 (irqchip: Gic:
   Support forced affinity setting)
 - fix arm64 pud_huge() to return 0 when only 2 levels page tables are
   used (__PAGETABLE_PMD_FOLDED defined and pmd_huge already covers
   block entries at the first level), otherwise KVM gets confused

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: fix pud_huge() for 2-level pagetables
  arm64: use cpu_online_mask when using forced irq_set_affinity

Pull Metag architecture and related fixes from James Hogan:
 "Mostly fixes for metag and parisc relating to upgrowing stacks.

   - Fix missing compiler barriers in metag memory barriers.
   - Fix BUG_ON on metag when RLIMIT_STACK hard limit is increased
     beyond safe value.
   - Make maximum stack size configurable.  This reduces the default
     user stack size back to 80MB (especially on parisc after their
     removal of _STK_LIM_MAX override).  This only affects metag and
     parisc.
   - Remove metag _STK_LIM_MAX override to match other arches and follow
     parisc, now that it is safe to do so (due to the BUG_ON fix
     mentioned above).
   - Finally now that both metag and parisc _STK_LIM_MAX overrides have
     been removed, it makes sense to remove _STK_LIM_MAX altogether"

* tag 'metag-for-v3.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag:
  asm-generic: remove _STK_LIM_MAX
  metag: Remove _STK_LIM_MAX override
  parisc,metag: Do not hardcode maximum userspace stack size
  metag: Reduce maximum stack size to 256MB
  metag: fix memory barriers

Pull drm/intel fixes from Dave Airlie:
 "Just some intel fixes.

  I have some radeon ones but I need to get some patches dropped from
  the pull req"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/i915: Increase WM memory latency values on SNB
  drm/i915: restore backlight precision when converting from ACPI
  drm/i915: Use the first mode if there is no preferred mode in the EDID
  drm/i915/dp: force eDP lane count to max available lanes on BDW
  drm/i915/vlv: reset VLV media force wake request register
  drm/i915/SDVO: For sysfs link put directory and target in correct order
  drm/i915: use lane count and link rate from VBT as minimums for eDP
  drm/i915: clean up VBT eDP link param decoding
  drm/i915: consider the source max DP lane count too

Pull x86 fixes from Peter Anvin.

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86-64, modify_ldt: Make support for 16-bit segments a runtime option
  x86, mm, hugetlb: Add missing TLB page invalidation for hugetlb_cow()
  x86, rdrand: When nordrand is specified, disable RDSEED as well

Pull timer fix from Thomas Gleixner:
 "A single bug fix for a long standing issue:

   - Updating the expiry value of a relative timer _after_ letting the
     idle logic select a target cpu for the timer based on its stale
     expiry value is outright stupid.  Thanks to Viresh for spotting the
     brainfart"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hrtimer: Set expiry time before switch_hrtimer_base()

Pull irq fixes from Thomas Gleixner:
 "Two small updates from the irq departement:

   - Provide missing inline stub for a SMP only function

   - Add sub-maintainer for the drivers/irqchip/ part of the irq
     subsystem.  YAY!"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  MAINTAINERS: Add co-maintainer for drivers/irqchip
  genirq: Provide irq_force_affinity fallback for non-SMP

Intel fixes for regressions, black screens and hangs, for 3.15.

* tag 'drm-intel-fixes-2014-05-16' of git://anongit.freedesktop.org/drm-intel:
  drm/i915: Increase WM memory latency values on SNB
  drm/i915: restore backlight precision when converting from ACPI
  drm/i915: Use the first mode if there is no preferred mode in the EDID
  drm/i915/dp: force eDP lane count to max available lanes on BDW
  drm/i915/vlv: reset VLV media force wake request register
  drm/i915/SDVO: For sysfs link put directory and target in correct order
  drm/i915: use lane count and link rate from VBT as minimums for eDP
  drm/i915: clean up VBT eDP link param decoding
  drm/i915: consider the source max DP lane count too

The following happens when trying to run a kvm guest on a kernel
configured for 64k pages. This doesn't happen with 4k pages:

  BUG: failure at include/linux/mm.h:297/put_page_testzero()!
  Kernel panic - not syncing: BUG!
  CPU: 2 PID: 4228 Comm: qemu-system-aar Tainted: GF            3.13.0-0.rc7.31.sa2.k32v1.aarch64.debug #1
  Call trace:
  [<fffffe0000096034>] dump_backtrace+0x0/0x16c
  [<fffffe00000961b4>] show_stack+0x14/0x1c
  [<fffffe000066e648>] dump_stack+0x84/0xb0
  [<fffffe0000668678>] panic+0xf4/0x220
  [<fffffe000018ec78>] free_reserved_area+0x0/0x110
  [<fffffe000018edd8>] free_pages+0x50/0x88
  [<fffffe00000a759c>] kvm_free_stage2_pgd+0x30/0x40
  [<fffffe00000a5354>] kvm_arch_destroy_vm+0x18/0x44
  [<fffffe00000a1854>] kvm_put_kvm+0xf0/0x184
  [<fffffe00000a1938>] kvm_vm_release+0x10/0x1c
  [<fffffe00001edc1c>] __fput+0xb0/0x288
  [<fffffe00001ede4c>] ____fput+0xc/0x14
  [<fffffe00000d5a2c>] task_work_run+0xa8/0x11c
  [<fffffe0000095c14>] do_notify_resume+0x54/0x58

In arch/arm/kvm/mmu.c:unmap_range(), we end up doing an extra put_page()
on the stage2 pgd which leads to the BUG in put_page_testzero(). This
happens because a pud_huge() test in unmap_range() returns true when it
should always be false with 2-level pages tables used by 64k pages.
This patch removes support for huge puds if 2-level pagetables are
being used.
Signed-off-by: NMark Salter <msalter@redhat.com>
[catalin.marinas@arm.com: removed #ifndef around PUD_SIZE check]
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Cc: <stable@vger.kernel.org> # v3.11+

The attached change significantly improves the performance of the LWS-CAS code
in syscall.S.
This allows a number of packages to build (e.g., zeromq3, gtest and libxs)
that previously failed because slow LWS-CAS performance under contention. In
particular, interrupts taken while the lock was taken degraded performance
significantly.

The change does the following:

1) Disables interrupts around the CAS operation, and
2) Changes the loads and stores to use the ordered completer, "o", on
PA 2.0. "o" and "ma" with a zero offset are equivalent. The latter is
accepted on both PA 1.X and 2.0.

The use of ordered loads and stores probably makes no difference on all
existing hardware, but it seemed pedantically correct. In particular, the CAS
operation must complete before LDCW lock is released. As written before, a
processor could reorder the operations.

I don't believe the period interrupts are disabled is long enough to
significantly increase interrupt latency. For example, the TLB insert code is
longer. Worst case is a memory fault in the CAS operation.
Signed-off-by: NJohn David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org # 3.13+
Signed-off-by: NHelge Deller <deller@gmx.de>

Ratelimit printing of userspace segfaults and make it runtime
configurable via the /proc/sys/debug/exception-trace variable. This
should resolve syslog from growing way too fast and thus prevents
possible system service attacks.
Signed-off-by: NHelge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # 3.13+

On SNB the BIOS provided WM memory latency values seem insufficient to
handle high resolution displays.

In this particular case the display mode was a 2560x1440@60Hz, which
makes the pixel clock 241.5 MHz. It was empirically found that a memory
latency value if 1.2 usec is enough to avoid underruns, whereas the BIOS
provided value of 0.7 usec was clearly too low. Incidentally 1.2 usec
is what the typical BIOS provided values are on IVB systems.

Increase the WM memory latency values to at least 1.2 usec on SNB.
Hopefully this won't have a significant effect on power consumption.

v2: Increase the latency values regardless of the pixel clock

Cc: Robert N <crshman@gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=70254Tested-by: NRobert Navarro <crshman@gmail.com>
Tested-by: NVitaly Minko <vitaly.minko@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

When we set backlight on behalf of ACPI opregion, we will convert the
backlight value in the 0-255 range defined in opregion to the actual
hardware level. Commit 22505b82 (drm/i915: avoid brightness overflow
when doing scale) is meant to fix the overflow problem when doing the
conversion, but it also caused a problem that the converted hardware
level doesn't quite represent the intended value: say user wants maximum
backlight level(255 in opregion's range), then we will calculate the
actual hardware level to be: level = freq / max * level, where freq is
the hardware's max backlight level(937 on an user's box), and max and
level are all 255. The converted value should be 937 but the above
calculation will yield 765.

To fix this issue, just use 64 bits to do the calculation to keep the
precision and avoid overflow at the same time.

Buglink: https://bugzilla.kernel.org/show_bug.cgi?id=72491Reported-by: NNico Schottelius <nico-bugzilla.kernel.org@schottelius.org>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: stable@vger.kernel.org
Signed-off-by: NAaron Lu <aaron.lu@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

This matches the algorithm used by earlier kernels when selecting the
mode for the fbcon. And only if there is no modes at all, do we fall
back to using the BIOS configuration. Seamless transition is still
preserved (from the BIOS configuration to ours) so long as the BIOS has
also chosen what we hope is the native configuration.
Reported-by: NKnut Petersen <Knut_Petersen@t-online.de>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=78655Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Tested-by: NKnut Petersen <Knut_Petersen@t-online.de>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
[Jani: applied Chris' "Please imagine that I wrote this correctly."]
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

There are certain BDW high res eDP machines that regressed due to

commit 38aecea0
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Mon Mar 3 11:18:10 2014 +0100

    drm/i915: reverse dp link param selection, prefer fast over wide again

The commit lead to 2 lanes at 5.4 Gbps being used instead of 4 lanes at
2.7 Gbps on the affected machines. Link training succeeded for both, but
the screen remained blank with the former config. Further investigation
showed that 4 lanes at 5.4 Gbps worked also.

The root cause for the blank screen using 2 lanes remains unknown, but
apparently the driver for a certain other operating system by default
uses the max available lanes. Follow suit on Broadwell eDP, for at least
until we figure out what is going on.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=76711Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@gmail.com>
Tested-by: NRodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

Checkin:

b3b42ac2 x86-64, modify_ldt: Ban 16-bit segments on 64-bit kernels

disabled 16-bit segments on 64-bit kernels due to an information
leak.  However, it does seem that people are genuinely using Wine to
run old 16-bit Windows programs on Linux.

A proper fix for this ("espfix64") is coming in the upcoming merge
window, but as a temporary fix, create a sysctl to allow the
administrator to re-enable support for 16-bit segments.

It adds a "/proc/sys/abi/ldt16" sysctl that defaults to zero (off). If
you hit this issue and care about your old Windows program more than
you care about a kernel stack address information leak, you can do

   echo 1 > /proc/sys/abi/ldt16

as root (add it to your startup scripts), and you should be ok.

The sysctl table is only added if you have COMPAT support enabled on
x86-64, but I assume anybody who runs old windows binaries very much
does that ;)
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/CA%2B55aFw9BPoD10U1LfHbOMpHWZkvJTkMcfCs9s3urPr1YyWBxw@mail.gmail.com
Cc: <stable@vger.kernel.org>

_STK_LIM_MAX could be used to override the RLIMIT_STACK hard limit from
an arch's include/uapi/asm-generic/resource.h file, but is no longer
used since both parisc and metag removed the override. Therefore remove
it entirely, setting the hard RLIMIT_STACK limit to RLIM_INFINITY
directly in include/asm-generic/resource.h.
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-arch@vger.kernel.org
Cc: Helge Deller <deller@gmx.de>
Cc: John David Anglin <dave.anglin@bell.net>

Meta overrode _STK_LIM_MAX (the default RLIMIT_STACK hard limit) to
256MB, apparently in an attempt to prevent setup_arg_pages's
STACK_GROWSUP code from choosing the maximum stack size of 1GB, which is
far too large for Meta's limited virtual address space and hits a BUG_ON
(stack_top is usually 0x3ffff000).

However the commit "metag: Reduce maximum stack size to 256MB" reduces
the absolute stack size limit to a safe value for metag. This allows the
default _STK_LIM_MAX override to be removed, bringing the default
behaviour in line with all other architectures. Parisc in particular
recently removed their override of _STK_LIMT_MAX in commit e0d8898d
(parisc: remove _STK_LIM_MAX override) since it subtly affects stack
allocation semantics in userland. Meta's uapi/asm/resource.h can now be
removed and switch to using generic-y.
Suggested-by: NHelge Deller <deller@gmx.de>
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Cc: John David Anglin <dave.anglin@bell.net>

This patch affects only architectures where the stack grows upwards
(currently parisc and metag only). On those do not hardcode the maximum
initial stack size to 1GB for 32-bit processes, but make it configurable
via a config option.

The main problem with the hardcoded stack size is, that we have two
memory regions which grow upwards: stack and heap. To keep most of the
memory available for heap in a flexmap memory layout, it makes no sense
to hard allocate up to 1GB of the memory for stack which can't be used
as heap then.

This patch makes the stack size for 32-bit processes configurable and
uses 80MB as default value which has been in use during the last few
years on parisc and which hasn't showed any problems yet.
Signed-off-by: NHelge Deller <deller@gmx.de>
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: linux-parisc@vger.kernel.org
Cc: linux-metag@vger.kernel.org
Cc: John David Anglin <dave.anglin@bell.net>

Specify the maximum stack size for arches where the stack grows upward
(parisc and metag) in asm/processor.h rather than hard coding in
fs/exec.c so that metag can specify a smaller value of 256MB rather than
1GB.

This fixes a BUG on metag if the RLIMIT_STACK hard limit is increased
beyond a safe value by root. E.g. when starting a process after running
"ulimit -H -s unlimited" it will then attempt to use a stack size of the
maximum 1GB which is far too big for metag's limited user virtual
address space (stack_top is usually 0x3ffff000):

BUG: failure at fs/exec.c:589/shift_arg_pages()!
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: linux-parisc@vger.kernel.org
Cc: linux-metag@vger.kernel.org
Cc: John David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org # only needed for >= v3.9 (arch/metag)

Volatile access doesn't really imply the compiler barrier. Volatile access
is only ordered with respect to other volatile accesses, it isn't ordered
with respect to general memory accesses. Gcc may reorder memory accesses
around volatile access, as we can see in this simple example (if we
compile it with optimization, both increments of *b will be collapsed to
just one):

void fn(volatile int *a, long *b)
{
	(*b)++;
	*a = 10;
	(*b)++;
}

Consequently, we need the compiler barrier after a write to the volatile
variable, to make sure that the compiler doesn't reorder the volatile
write with something else.
Signed-off-by: NMikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>

Commit f4ae17aa [MIPS: mm: Use scratch for
PGD when !CONFIG_MIPS_PGD_C0_CONTEXT] broke microMIPS kernel builds. This
patch refactors that code similar to what was done for the 'clear_page'
and 'copy_page' functions.
Signed-off-by: NSteven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6744/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The if condition here was supposed to return on error but the return
statement is missing.  The effect is that the ->mixername is set to
"???" instead of "DT019X".
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Merge tag 'asoc-v3.15-rc5-intel' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Intel fixes for v3.15

This is a relatively large batch of fixes for the newly added
Haswell/Baytrail drivers from Intel.  It's a bit larger than is good for
this point in the cycle but it's all for a newly added driver so not so
worrying as it might otherwise be.  Some of it's integration problems,
some of it's the sort of problem usually turned up in stress tests.

Merge tag 'asoc-v3.15-rc5-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Driver fixes for v3.15

A small set of driver fixes, nothing remarkable in itself or of any
relevance outside of the driver.

Merge tag 'asoc-v3.15-rc5-core' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Core fixes for v3.15

A few things here:

 - Fix the creation of spurious CODEC<->CODEC links which caused DAPM to
   have audio paths which shouldn't be present causing spurious powerups
   and potential audible issues for users.
 - Ensure the suspend->off transition doesn't have spurious transitions
   to prepare added to the sequence.
 - Fix incorrect skipping of PCM suspension for active audio streams.
 - Remove Timur Tabi from the CS4270 maintainers, Cirrus are now doing
   this and Timur no longer has the boards that he was using.