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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boot	ARC: perf: Rename DT binding to not confuse with power mgmt	2015-04-20 18:27:36 +05:30
configs	ARC: [nsimosci] Update defconfig	2015-04-13 15:14:56 +05:30
include	ARC: unbork !LLSC build	2015-05-10 12:06:57 +05:30
kernel	ARC changes for 4.1-rc1:	2015-04-24 07:55:54 -07:00
lib	ARC: switch to generic ENTRY/END assembler annotations	2014-03-26 14:31:28 +05:30
mm	mm/fault, arch: Use pagefault_disable() to check for disabled pagefaults in the handler	2015-05-19 08:39:15 +02:00
oprofile	ARC: OProfile support	2013-02-15 23:16:00 +05:30
plat-arcfpga	ARC: [arcfpga] Get rid of ARC_BOARD_ANGEL4 and ARC_BOARD_ML509	2014-10-13 14:46:14 +05:30
plat-tb10x	ARC: [plat*] move code out of .init_machine into common	2014-10-13 14:46:13 +05:30
Kbuild	ARC: Build system: Makefiles, Kconfig, Linker script	2013-02-11 20:00:25 +05:30
Kconfig	ARC: add power management options	2014-11-03 18:05:43 +05:30
Kconfig.debug	ARC: With earlycon in use, retire EARLY_PRINTK	2015-05-11 11:20:21 +05:30
Makefile	ARC: rename default defconfig	2014-12-17 15:23:56 +05:30