linux/arch/m68k
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
..
68000 m68k: fix crufty 68000 and 68360 intro comments 2014-09-29 09:18:35 +10:00
68360 arch: m68k: 68360: config: Remove unused function 2015-02-03 14:16:23 +10:00
amiga m68k/amiga: Convert printk(foo to pr_foo() 2014-05-28 10:11:54 +02:00
apollo m68k/apollo: Convert printk to pr_foo() 2014-05-28 10:11:55 +02:00
atari m68k/atari: Remove obsolete IRQ_TYPE_* 2015-01-15 13:44:51 +01:00
bvme6000 m68k/UAPI: Use proper types (endianness/size) in <asm/bootinfo*.h> 2013-11-26 11:09:21 +01:00
coldfire Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu 2015-04-20 10:12:29 -07:00
configs m68k/defconfig: Update defconfigs for v4.0-rc1 2015-03-15 10:24:48 +01:00
emu Merge branch 'for-3.14/core' of git://git.kernel.dk/linux-block 2014-01-30 11:19:05 -08:00
fpsp040
hp300 m68k/hp300: Convert printk to pr_foo() 2014-05-28 10:11:55 +02:00
ifpsp060
include sched/preempt: Merge preempt_mask.h into preempt.h 2015-05-19 08:39:11 +02:00
kernel Merge branch 'exec_domain_rip_v2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc 2015-04-15 13:53:55 -07:00
lib m68k: Remove FSF address 2015-03-15 10:23:30 +01:00
mac m68k/mac: Fix out-of-bounds array index in OSS IRQ source initialization 2015-03-30 10:14:34 +02:00
math-emu
mm mm/fault, arch: Use pagefault_disable() to check for disabled pagefaults in the handler 2015-05-19 08:39:15 +02:00
mvme16x m68k/mvme16x: rtc - Don't use module_init in non-modular code 2015-01-11 11:38:41 +01:00
mvme147 m68k/mvme147: config.c - Remove unused functions 2015-01-11 11:38:45 +01:00
q40 m68k: Mark functions only called from setup_arch() __init 2013-11-26 11:08:54 +01:00
sun3 sun3_scsi: Convert to platform device 2014-11-20 09:11:15 +01:00
sun3x m68k: Remove superfluous inclusions of <asm/bootinfo.h> 2013-11-26 11:09:22 +01:00
tools/amiga
install.sh
Kconfig m68k: mark PMD folded and expose number of page table levels 2015-04-14 16:49:02 -07:00
Kconfig.bus
Kconfig.cpu
Kconfig.debug m68k: Multi-platform EARLY_PRINTK 2014-05-28 10:10:04 +02:00
Kconfig.devices Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k 2014-10-08 05:40:17 -04:00
Kconfig.machine
Makefile m68k: move non-mmu 68360 platform code 2014-09-29 09:18:35 +10:00