linux-sg2042/arch/mn10300/mm
David Hildenbrand 70ffdb9393 mm/fault, arch: Use pagefault_disable() to check for disabled pagefaults in the handler
Introduce faulthandler_disabled() and use it to check for irq context and
disabled pagefaults (via pagefault_disable()) in the pagefault handlers.

Please note that we keep the in_atomic() checks in place - to detect
whether in irq context (in which case preemption is always properly
disabled).

In contrast, preempt_disable() should never be used to disable pagefaults.
With !CONFIG_PREEMPT_COUNT, preempt_disable() doesn't modify the preempt
counter, and therefore the result of in_atomic() differs.
We validate that condition by using might_fault() checks when calling
might_sleep().

Therefore, add a comment to faulthandler_disabled(), describing why this
is needed.

faulthandler_disabled() and pagefault_disable() are defined in
linux/uaccess.h, so let's properly add that include to all relevant files.

This patch is based on a patch from Thomas Gleixner.

Reviewed-and-tested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: airlied@linux.ie
Cc: akpm@linux-foundation.org
Cc: benh@kernel.crashing.org
Cc: bigeasy@linutronix.de
Cc: borntraeger@de.ibm.com
Cc: daniel.vetter@intel.com
Cc: heiko.carstens@de.ibm.com
Cc: herbert@gondor.apana.org.au
Cc: hocko@suse.cz
Cc: hughd@google.com
Cc: mst@redhat.com
Cc: paulus@samba.org
Cc: ralf@linux-mips.org
Cc: schwidefsky@de.ibm.com
Cc: yang.shi@windriver.com
Link: http://lkml.kernel.org/r/1431359540-32227-7-git-send-email-dahi@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19 08:39:15 +02:00
..
Kconfig.cache MN10300: Create general kernel debugger cache flushing 2011-03-18 16:54:30 +00:00
Makefile MN10300: Create general kernel debugger cache flushing 2011-03-18 16:54:30 +00:00
cache-dbg-flush-by-reg.S MN10300: Fix one of the kernel debugger cacheflush variants 2011-06-07 19:03:52 -07:00
cache-dbg-flush-by-tag.S MN10300: Create general kernel debugger cache flushing 2011-03-18 16:54:30 +00:00
cache-dbg-inv-by-reg.S MN10300: Create general kernel debugger cache flushing 2011-03-18 16:54:30 +00:00
cache-dbg-inv-by-tag.S MN10300: Create general kernel debugger cache flushing 2011-03-18 16:54:30 +00:00
cache-dbg-inv.S MN10300: Create general kernel debugger cache flushing 2011-03-18 16:54:30 +00:00
cache-disabled.c MN10300: Handle missing sys_cacheflush() when caching disabled 2010-09-28 18:01:14 -07:00
cache-flush-by-reg.S MN10300: AM34: Add cacheflushing by using the AM34 purge registers 2010-10-27 17:28:45 +01:00
cache-flush-by-tag.S MN10300: Create general kernel debugger cache flushing 2011-03-18 16:54:30 +00:00
cache-flush-icache.c MN10300: Cache: Implement SMP global cache flushing 2010-10-27 17:28:47 +01:00
cache-inv-by-reg.S MN10300: Create general kernel debugger cache flushing 2011-03-18 16:54:30 +00:00
cache-inv-by-tag.S MN10300: Create general kernel debugger cache flushing 2011-03-18 16:54:30 +00:00
cache-inv-icache.c MN10300: The SMP_ICACHE_INV_FLUSH_RANGE IPI command does not exist 2011-03-14 14:45:29 +00:00
cache-smp-flush.c MN10300: Cache: Implement SMP global cache flushing 2010-10-27 17:28:47 +01:00
cache-smp-inv.c MN10300: Cache: Implement SMP global cache flushing 2010-10-27 17:28:47 +01:00
cache-smp.c mn10300: convert old cpumask API into new one 2011-05-25 08:39:39 -07:00
cache-smp.h MN10300: Cache: Implement SMP global cache flushing 2010-10-27 17:28:47 +01:00
cache.c MN10300: Cache: Implement SMP global cache flushing 2010-10-27 17:28:47 +01:00
cache.inc MN10300: The icache invalidate functions should disable the icache first 2011-03-18 16:54:29 +00:00
dma-alloc.c mn10300: mm/dma-alloc.c needs <linux/export.h> 2012-07-11 16:04:42 -07:00
extable.c mn10300: add the MN10300/AM33 architecture to the kernel 2008-02-08 09:22:30 -08:00
fault.c mm/fault, arch: Use pagefault_disable() to check for disabled pagefaults in the handler 2015-05-19 08:39:15 +02:00
init.c mm/mn10300: prepare for removing num_physpages and simplify mem_init() 2013-07-03 16:07:37 -07:00
misalignment.c Disintegrate asm/system.h for MN10300 2012-03-28 18:30:02 +01:00
mmu-context.c MN10300: Make the use of PIDR to mark TLB entries controllable 2010-10-27 17:28:49 +01:00
pgtable.c mn10300: add missing pgtable_page_ctor/dtor calls 2013-11-15 09:32:16 +09:00
tlb-mn10300.S MN10300: Use the [ID]PTEL2 registers rather than [ID]PTEL for TLB control 2010-10-27 17:28:50 +01:00
tlb-smp.c arch,mn10300: Convert smp_mb__*() 2014-04-18 14:20:39 +02:00