linux_dsm_epyc7002/arch/parisc/kernel
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
..
.gitignore parisc: add arch/parisc/kernel/.gitignore 2008-10-10 16:32:28 +00:00
asm-offsets.c arch: Remove exec_domain from remaining archs 2015-04-12 21:03:30 +02:00
audit.c parisc: add kernel audit feature 2013-11-07 22:27:20 +01:00
binfmt_elf32.c parisc: fix redefinition of SET_PERSONALITY 2013-03-02 20:15:28 +01:00
cache.c parisc: change value of SHMLBA from 0x00400000 to PAGE_SIZE 2014-04-13 15:00:53 +02:00
compat_audit.c parisc: add kernel audit feature 2013-11-07 22:27:20 +01:00
drivers.c parisc/PCI: Use dev_is_pci() to identify PCI devices 2013-12-11 16:53:12 -07:00
entry.S parisc: expose number of page table levels on Kconfig level 2015-04-14 16:49:02 -07:00
firmware.c parisc: delete __cpuinit usage from all users 2013-07-14 19:36:51 -04:00
ftrace.c parisc: ftrace: Remove check of obsolete variable function_trace_stop 2014-07-18 13:57:05 -04:00
hardware.c parisc: add serial ports of C8000/1GHz machine to hardware database 2014-07-13 15:51:58 +02:00
head.S parisc: expose number of page table levels on Kconfig level 2015-04-14 16:49:02 -07:00
hpmc.S parisc: fix partly 16/64k PAGE_SIZE boot 2013-05-06 23:08:32 +02:00
inventory.c parisc: Fix interrupt routing for C8000 serial ports 2013-07-31 23:42:32 +02:00
irq.c parisc: fix up obsolete cpu function usage. 2015-03-05 15:25:08 +10:30
Makefile parisc: add kernel audit feature 2013-11-07 22:27:20 +01:00
module.c mm: vmalloc: pass additional vm_flags to __vmalloc_node_range() 2015-02-13 21:21:42 -08:00
pa7300lc.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
pacache.S parisc: Use unshadowed index register for flush instructions in flush_dcache_page_asm and flush_icache_page_asm 2013-06-18 20:29:10 +02:00
parisc_ksyms.c parisc: Provide __ucmpdi2 to resolve undefined references in 32 bit builds. 2013-04-25 22:36:15 +02:00
pci-dma.c parisc: Eliminate sg_virt_addr() and private scatterlist.h 2015-04-21 22:02:43 +02:00
pci.c parisc: provide pci_mmap_page_range() for parisc 2013-06-18 20:29:08 +02:00
pdc_chassis.c parisc: single_open() leaks 2013-05-05 00:10:41 -04:00
pdc_cons.c TTY: switch tty_flip_buffer_push 2013-01-15 22:30:15 -08:00
perf_asm.S Revert "parisc: fix trivial section name warnings" 2008-06-13 10:49:45 -04:00
perf_images.h [PARISC] Use kzalloc and other janitor-style cleanups 2006-01-22 20:26:31 -05:00
perf.c parisc: remove big kernel lock 2010-10-16 22:43:08 +02:00
process.c parisc: copy_thread(): rename 'arg' argument to 'kthread_arg' 2015-04-24 13:45:55 +02:00
processor.c parisc: delete __cpuinit usage from all users 2013-07-14 19:36:51 -04:00
ptrace.c Merge git://git.infradead.org/users/eparis/audit 2014-10-19 16:25:56 -07:00
real2.S parisc: move pdc_result to real2.S 2008-10-10 16:32:28 +00:00
setup.c parisc: correctly display number of active CPUs 2013-11-07 22:29:05 +01:00
signal32.c constify copy_siginfo_to_user{,32}() 2013-11-09 00:16:29 -05:00
signal32.h constify copy_siginfo_to_user{,32}() 2013-11-09 00:16:29 -05:00
signal.c parisc: hpux - Remove hpux gateway page 2015-02-16 22:35:06 +01:00
smp.c parisc: Remove unused function 2015-02-17 10:41:19 +01:00
stacktrace.c parisc: add LATENCYTOP_SUPPORT and CONFIG_STACKTRACE_SUPPORT 2009-03-31 02:51:34 +00:00
sys_parisc32.c parisc: drop unused defines and header includes 2014-07-13 15:56:12 +02:00
sys_parisc.c parisc,metag: Fix crashes due to stack randomization on stack-grows-upwards architectures 2015-05-12 22:03:44 +02:00
syscall_table.S parisc: Add compile-time check when adding new syscalls 2015-03-23 10:57:25 +01:00
syscall.S parisc: Implement new LWS CAS supporting 64 bit operations. 2014-09-13 22:40:48 +02:00
time.c parisc: move definition of PAGE0 to asm/page.h 2012-05-10 15:12:08 -07:00
topology.c parisc: Replace NR_CPUS in parisc code 2009-01-05 19:09:02 +00:00
traps.c mm/fault, arch: Use pagefault_disable() to check for disabled pagefaults in the handler 2015-05-19 08:39:15 +02:00
unaligned.c parisc: show number of FPE and unaligned access handler calls in /proc/interrupts 2013-05-24 22:35:26 +02:00
unwind.c parisc: use kernel_text_address() in unwind functions 2013-11-30 22:08:54 +01:00
vmlinux.lds.S parisc: fix kernel memory layout in vmlinux.ld.S 2013-11-30 22:09:21 +01:00