Oleg Nesterov found an interesting deadlock possibility:
> sysrq_showregs_othercpus() does smp_call_function(showacpu)
> and showacpu() show_stack()->decode_address(). Now suppose that IPI
> interrupts the task holding read_lock(tasklist).
To fix this, blackfin should not grab the write_ variant of the
tasklist lock, read_ one is enough.
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Cc: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The patch fixes two problems:
1. Working with task->mm w/o getting mm or grabing the task lock is
dangerous as ->mm might disappear (exit_mm() assigns NULL under
task_lock(), so tasklist lock is not enough).
We can't use get_task_mm()/mmput() pair as mmput() might sleep,
so we have to take the task lock while handle its mm.
2. Checking for process->mm is not enough because process' main
thread may exit or detach its mm via use_mm(), but other threads
may still have a valid mm.
To catch this we use find_lock_task_mm(), which walks up all
threads and returns an appropriate task (with task lock held).
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Cc: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Checking for process->mm is not enough because process' main thread may
exit or detach its mm via use_mm(), but other threads may still have a
valid mm.
To fix this we would need to use find_lock_task_mm(), which would walk up
all threads and returns an appropriate task (with task lock held).
clear_tasks_mm_cpumask() has the issue fixed, so let's use it.
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Current CPU hotplug code has some task->mm handling issues:
1. Working with task->mm w/o getting mm or grabing the task lock is
dangerous as ->mm might disappear (exit_mm() assigns NULL under
task_lock(), so tasklist lock is not enough).
We can't use get_task_mm()/mmput() pair as mmput() might sleep,
so we must take the task lock while handle its mm.
2. Checking for process->mm is not enough because process' main
thread may exit or detach its mm via use_mm(), but other threads
may still have a valid mm.
To fix this we would need to use find_lock_task_mm(), which would
walk up all threads and returns an appropriate task (with task
lock held).
clear_tasks_mm_cpumask() has all the issues fixed, so let's use it.
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Checking for process->mm is not enough because process' main thread may
exit or detach its mm via use_mm(), but other threads may still have a
valid mm.
To fix this we would need to use find_lock_task_mm(), which would walk up
all threads and returns an appropriate task (with task lock held).
clear_tasks_mm_cpumask() has this issue fixed, so let's use it.
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit d065bd810b ("mm: retry page fault when blocking on disk
transfer") and commit 37b23e0525 ("x86,mm: make pagefault killable")
introduced changes into the x86 pagefault handler for making the page
fault handler retryable as well as killable.
These changes reduce the mmap_sem hold time, which is crucial during OOM
killer invocation.
Port these changes to um.
Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The Nomadik GPIO controller now relies on Nomadik pinctrl, however
the pinctrl driver is not currently started by any ux500 platform.
This is requred or GPIOs do not work at all.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Here we supply the information required to setup regulators successfully
on Snowball and other db8500 variants which use the ab8500 regulators.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This patch adds a fixed regulator for use by the SMSC911x Ethernet
chip driver into the db8500 Device Tree. It also references other
regulators required by the same device.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This patch adds the correct compatible string for use during Device Tree
population. Without it the DB8500 PRCMU regulators would be processed
when DT is enabled.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Here we inform Device Tree of which regulators are provided by the db8500-
prcmu. This way we can reference some of their consumers directly from the
Device Tree e.g. SMSC911x Ethernet chip.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
ST-Ericsson uses User Interface Boards to extend functionality of
some of their development boards. However, these aren't compatible
with all the supported boards found in Mainline (Snowball for
instance). This patch ensures that the UIBs are only probed on
boards which can actually support them. This in turn saves lots of
unnecessary error messages normally found in Snowball's boot log.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The final piece of the ab8500 puzzle. Here we prevent any of the ab8500-*
drivers from being registered from platform code when Device Tree is
enabled, as we expect DT do probe each of these individually. We also
provide the relevant compatible strings, so that DT knows which nodes
it needs to pay attention to during population.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This patch applies the correct format requested by the irq
domain. For chained IRQs which use GPIO lines as IRQs, we
stipulate that a two cell request is required. The first cell
contains the requested IRQ and the second can contain flags
pertaining to edge detection and level sensitive values. The
zeroth cell specifies the GPIO controller by use of a phandle.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The patch to disable SMSC911x registration was applied twice in the upstream
kernel by mistake. Git interpreted this as 'take the same entry from a
similar struct' which was close by. This was the wrong thing to do. This patch
rectifies this error and re-enables SMSC911x registration when Device Tree is
not enabled.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Apply db8500 related PRCMU Device Tree settings and clean up some formatting
errors. We also remove one of the PRCMU assigned IRQs, as it is currently not
used.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Now the DB8500 has Device Tree support it will be probed when the DT
is parsed, rendering the requirement for platform registration void.
This patch removes DB8500 PRCMU platform registration.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Now the SCMC911x is correctly enabled in Device Tree, there is no need
to continue registering it from platform code. In fact, if we continue
doing so, the system will throw an error on boot.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
During Device Tree enablement it is necessary to remove
<hw_component>_add_<device> calls one at at time, as and when particular
devices are DT enabled. This patch provides a temporary solution. Once
the new *of_init_devices function has been fully unpopulated it will be
removed again.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
During Device Tree enablement it is necessary to remove snowball_<device>*
platform_data segments one at at time, as and when particular devices are
DT enabled. This patch provides a temporary solution. Once this new struct
is empty it will be removed again.
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Pull two small kvm fixes from Avi Kivity:
"A build fix for non-kvm archs and a transparent hugepage refcount
bugfix on hosts with 4M pages."
* git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: Export asm-generic/kvm_para.h
KVM: MMU: fix huge page adapted on non-PAE host
Pull s390 patches from Heiko Carstens:
"A couple of s390 patches for the 3.5 merge window. Just a collection
of bug fixes and cleanups."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/uaccess: fix access_ok compile warnings
s390/cmpxchg: select HAVE_CMPXCHG_LOCAL option
s390/cmpxchg: fix sign extension bugs
s390/cmpxchg: fix 1 and 2 byte memory accesses
s390/cmpxchg: fix compile warnings specific to s390
s390/cmpxchg: add missing memory barrier to cmpxchg64
s390/cpu: remove cpu "capabilities" sysfs attribute
s390/kernel: Fix smp_call_ipl_cpu() for offline CPUs
s390/kernel: Introduce memcpy_absolute() function
s390/headers: replace __s390x__ with CONFIG_64BIT where possible
s390/headers: remove #ifdef __KERNEL__ from not exported headers
s390/irq: split irq stats for cpu-measurement alert facilities
s390/kexec: Move early_pgm_check_handler() to text section
s390/kdump: Use real mode for PSW restart and kexec
s390/kdump: Account /sys/kernel/kexec_crash_size changes in OS info
s390/kernel: Remove OS info init function call and diag 308 for kdump
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Merge tag 'parisc-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6
Pull misc parisc updates from James Bottomley:
"This is a couple of updates to complete our fixes and one to fix a
compile failure caused during the merge window. Additionally, we now
switch to the generic strncopy_from_user."
* tag 'parisc-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6:
[PARISC] update parisc to use generic strncpy_from_user()
[PARISC] Fix parisc compile failure after smp: Add task_struct argument to __cpu_up()
[PARISC] fix TLB fault path on PA2.0 narrow systems
[PARISC] fix boot failure on 32-bit systems caused by branch stubs placed before .text
Pull additional x86 fixes from Peter Anvin.
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, amd, xen: Avoid NULL pointer paravirt references
x86, mtrr: Fix a type overflow in range_to_mtrr func
x86, realmode: Unbreak the ia64 build of drivers/acpi/sleep.c
x86/mm/pat: Improve scaling of pat_pagerange_is_ram()
x86: hpet: Fix copy-and-paste mistake in earlier change
x86/mce: Fix 32-bit build
x86/bitops: Move BIT_64() for a wider use
This branch contains a few development patches for Samsung and Versatile
Express that were submitted to arm-soc near the beginning of the merge
window. We picked them up with the agreement that they would need to
sit in linux-next for a while, and now they have.
There are also two fixes:
- One long-standing build breakage on ixp4xx due to missing gpiolib
dependencies.
- The other is for some gpio device tree changes needed on lpc32xx.
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Merge tag 'devel-late' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull late-merged development and first fixes for arm-soc from Olof Johansson:
"This branch contains a few development patches for Samsung and
Versatile Express that were submitted to arm-soc near the beginning of
the merge window. We picked them up with the agreement that they
would need to sit in linux-next for a while, and now they have.
There are also two fixes:
- One long-standing build breakage on ixp4xx due to missing gpiolib
dependencies.
- The other is for some gpio device tree changes needed on lpc32xx."
* tag 'devel-late' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
ARM: LPC32xx: Adjust dts files to gpio dt binding
ixp4xx: fix compilation by adding gpiolib support
ARM: vexpress: Remove twice included header files
ARM: vexpress: Device Tree updates
ARM: EXYNOS: Support suspend and resume for EXYNOS5250
ARM: EXYNOS: Add Clock register list for save and restore
ARM: EXYNOS: Add PMU table for EXYNOS5250
ARM: EXYNOS: Rename of function for pm.c
ARM: EXYNOS: Remove GIC save & restore function
ARM: dts: Add node for interrupt combiner controller on EXYNOS5250
ARM: S3C24XX: add support for second irq set of S3C2416
ARM: S3C64XX: use timekeeping wrapper on cpuidle
ARM: S3C64XX: declare the states with the new api on cpuidle
ARM: S3C64XX: Hook up carrier class modules on Cragganmore
ARM: S3C64XX: Initial hookup for Bells module on Cragganmore
Pull Sparc updates from David S. Miller:
1) Remove the idiotic situation wherein Leon was a special case in all
of the TLB/cache handling code.
The worst side effect of this bogosity is that you couldn't build a
kernel with Leon support enabled (to get better build coverage), and
test boot it on a non-LEON cpu.
Leon is, in all core respects, programatically identical to the
32-bit SRMMU. Except that they put the TLB registers in a different
alternate address space location.
Through code patching (for fast paths) and run time checks, this
issue is now a thing of the past.
From Sam Ravnborg.
2) There was a mis-merge of arch/sparc/Kconfig for one of the
clockevents changes that went in, causing 32-bit sparc to start
failing to build.
I merged in your tree to get those clockevents changes (and added a
note to the merge commit) then added Stephen Rothwell's fix for the
merge error.
3) Software quad floating point emulation was not working properly on
more recent Niagara chips, because the way the situation is reported
by the cpu has changed.
Nobody noticed because gcc emits calls to software emulation
routines in glibc.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc: (25 commits)
sparc: fix sparc64 build due to leon.h inclusion
sparc32: remove unused variable in head_32.S
sparc32,leon: fix leon bootup
sparc32: Export leon_dma_ops to modules.
sparc32: support leon + sun in dma_make_coherent()
sparc32,leon: always support leon in ioport
sparc32,leon: always include leon_pmc in build
sparc32: refactor cpu_idle()
sparc32: srmmu_probe now knows about leon too
sparc32: drop LEON hack for ASI_M_MMUREGS
sparc32: introduce run-time patching of srmmu access functions
sparc32: introduce support for run-time patching for all shared assembler code
sparc32,leon: fix section mismatch warning
sparc32,leon: always include leon_smp + leon_mm in build
sparc32,leon: always include leon_kernel in build
sparc32,leon: clean up leon.h
sparc32: handle leon in cpu.c
sparc32: handle leon in irq_32.c
sparc32: add support for run-time patching of leon/sun single instructions
sparc32: introduce sparc32_start_kernel called from head_32.S
...
get_unmapped_area() returns -E... on failure, not 0. Moreover, the
wrapper around it is completely pointless.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The GPIO devicetree binding in 3.5 doesn't register the various LPC32xx GPIO
banks via DT subnodes but always all at once, and changes the gpio referencing
to 3 cells (bank, gpio, flags). This patch adjusts the DTS files to this
binding that was just accepted to the gpio subsystem.
Signed-off-by: Roland Stigge <stigge@antcom.de>
Signed-off-by: Olof Johansson <olof@lixom.net>
Stub out MSR methods that aren't actually needed. This fixes a crash
as Xen Dom0 on AMD Trinity systems. A bigger patch should be added to
remove the paravirt machinery completely for the methods which
apparently have no users!
Reported-by: Andre Przywara <andre.przywara@amd.com>
Link: http://lkml.kernel.org/r/20120530222356.GA28417@andromeda.dapyr.net
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: <stable@vger.kernel.org>
* late/soc:
ARM: vexpress: Remove twice included header files
ARM: vexpress: Device Tree updates
ARM: EXYNOS: Support suspend and resume for EXYNOS5250
ARM: EXYNOS: Add Clock register list for save and restore
ARM: EXYNOS: Add PMU table for EXYNOS5250
ARM: EXYNOS: Rename of function for pm.c
ARM: EXYNOS: Remove GIC save & restore function
ARM: dts: Add node for interrupt combiner controller on EXYNOS5250
ARM: S3C24XX: add support for second irq set of S3C2416
Use unsigned long for dealing with jiffies not int. Rename the
callback to something sensible. Use __this_cpu_read/write for
accessing per cpu data.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
When boot on sun G5+ with 4T mem, see an overflow in mtrr cleanup as below.
*BAD*gran_size: 2G chunk_size: 2G num_reg: 10 lose cover RAM:
-18014398505283592M
This is because 1<<31 sign extended. Use an unsigned long constant to
fix it. Useful for mem larger than or equal to 4T.
-v2: Use 64bit constant instead of explicit type conversion as suggested
by Yinghai. Description updated too.
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Link: http://lkml.kernel.org/r/4FC5A77F.6060505@oracle.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Revert usage of acpi_wakeup_address and move definition
to x86 architecture code in order to make compilation work
in ia64.
[jsakkine: tested compilation in ia64/x86-64 and added
proper commit message]
Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Originally-by: H. Peter Anvin <hpa@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com>
Link: http://lkml.kernel.org/r/1338370421-27735-1-git-send-email-jarkko.sakkinen@intel.com
Cc: Tony Luck <tony.luck@intel.com>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Since nr_cpus_allowed is used outside of sched/rt.c and wants to be
used outside of there more, move it to a more natural site.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-kr61f02y9brwzkh6x53pdptm@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit commit 8e7fbcbc2 ("sched: Remove stale power aware scheduling
remnants and dysfunctional knobs") made a boo-boo with removing the
power aware scheduling muck from the x86 topology bits.
We should unconditionally use the llc_shared mask for multi-core.
Reported-and-tested-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Borislav Petkov <bp@amd64.org>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Link: http://lkml.kernel.org/n/tip-lsksc2kfyeveb13avh327p0d@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Function pat_pagerange_is_ram() scales poorly to large address
ranges, because it probes the resource tree for each page.
On a 2.6 GHz Opteron, this function consumes 34 ms for a 1 GB range.
It is called twice during untrack_pfn_vma(), slowing process
cleanup and handicapping the OOM killer.
This replacement consumes less than 1ms, under the same conditions.
Signed-off-by: John Dykstra <jdykstra@cray.com> on behalf of Cray Inc.
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1337980366.1979.6.camel@redwood
[ Small stylistic cleanups and renames ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On s390 access_ok is a macro which discards all parameters and always
returns 1. This can result in compile warnings which warn about unused
variables like this:
fs/read_write.c: In function 'rw_copy_check_uvector':
fs/read_write.c:684:16: warning: unused variable 'buf' [-Wunused-variable]
Fix this by adding a __range_ok() function which consumes all parameters
but still always returns 1.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Now that hopefully all cmpxchg/xchg bugs have been fixed select
HAVE_CMPXCHG_LOCAL option which uncovered a couple of bugs on s390.
The only call site which is affected seems to be within mm/vmstat.c.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
For 1 and 2 byte operands for xchg and cmpxchg the old and new values
get or'ed into the larger 4 byte old value before the compare and swap
instruction gets executed. This is done without using the proper byte
mask before or'ing the values.
If the caller passed in negative old or new values these got sign
extended by the caller. Which in turn means that either the old value
never matches, or, even worse, unrelated bytes would be changed in memory.
Luckily there don't seem to be any callers around yet, since that would
have resulted in the specification exception fixed in an earlies patch.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
