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
..
cache.S	arm64: compat: align cacheflush syscall with arch/arm	2014-12-01 13:31:12 +00:00
context.c	arm64: Process management	2012-09-17 13:41:58 +01:00
copypage.c	arm64: export __cpu_{clear,copy}_user_page functions	2014-07-08 17:30:51 +01:00
dma-mapping.c	arm64: add missing PAGE_ALIGN() to __dma_free()	2015-04-29 17:39:39 +01:00
dump.c	arm64: mm: Fix build error with CONFIG_SPARSEMEM_VMEMMAP disabled	2015-05-05 12:22:17 +01:00
extable.c	arm64: MMU fault handling and page table management	2012-09-17 13:41:57 +01:00
fault.c	mm/fault, arch: Use pagefault_disable() to check for disabled pagefaults in the handler	2015-05-19 08:39:15 +02:00
flush.c	arm64: mm: enable RCU fast_gup	2014-10-09 22:26:01 -04:00
hugetlbpage.c	mm/hugetlb: reduce arch dependent code around follow_huge_*	2015-02-11 17:06:01 -08:00
init.c	arm64: add support for memtest	2015-04-14 16:49:06 -07:00
ioremap.c	arm64: add ioremap physical address information	2015-01-23 15:29:06 +00:00
Makefile	arm64: add support to dump the kernel page tables	2014-11-26 17:19:18 +00:00
mm.h	arm64: add better page protections to arm64	2015-01-22 14:54:29 +00:00
mmap.c	mm: expose arch_mmap_rnd when available	2015-04-14 16:49:05 -07:00
mmu.c	arm64 updates for 4.1:	2015-04-16 13:58:29 -05:00
pageattr.c	arm64: mm: unexport set_memory_ro and set_memory_rw	2015-03-19 10:43:56 +00:00
pgd.c	arm64: pgalloc: consistently use PGALLOC_GFP	2014-11-20 12:05:18 +00:00
proc-macros.S	arm64: mm: increase VA range of identity map	2015-03-23 11:35:29 +00:00
proc.S	arm64: mm: increase VA range of identity map	2015-03-23 11:35:29 +00:00