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
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boards	ARM: SoC driver changes for 3.17	2014-08-08 11:34:32 -07:00
boot	avr32: fix out-of-range jump in large kernels	2013-11-20 09:53:21 +01:00
configs	avr32: update all default configurations	2015-02-09 15:27:45 +01:00
include	mm/uaccess, mm/fault: Clarify that uaccess may only sleep if pagefaults are enabled	2015-05-19 08:39:14 +02:00
kernel	arch: Remove exec_domain from remaining archs	2015-04-12 21:03:30 +02:00
lib	ARCH: drivers remove __dev* attributes.	2013-01-03 15:57:13 -08:00
mach-at32ap	Merge branch 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma	2015-02-18 08:49:20 -08:00
mm	mm/fault, arch: Use pagefault_disable() to check for disabled pagefaults in the handler	2015-05-19 08:39:15 +02:00
oprofile	oprofilefs_create_...() do not need superblock argument	2013-09-03 22:52:48 -04:00
Kconfig	Remove GENERIC_HARDIRQ config option	2013-09-13 15:09:52 +02:00
Kconfig.debug	[AVR32] Include instrumentation menu	2008-01-25 08:31:40 +01:00
Makefile	avr32: Makefile: add '-D__linux__' flag for gcc-4.4.7 use	2014-02-17 11:24:43 +01:00