diff options
| author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2017-07-19 14:49:40 +1000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2017-08-03 16:06:49 +1000 |
| commit | 11ccdd33d6ad8d0ade866fc1c6c691c0c57b6ace (patch) | |
| tree | e9218255e8c3be542dd71c98266cf0fbd8e6ff1b /arch/powerpc/mm/fault.c | |
| parent | 2865d08dd9ea876524652f3900b4b3b9c8b22e77 (diff) | |
| download | linux-11ccdd33d6ad8d0ade866fc1c6c691c0c57b6ace.tar.bz2 | |
powerpc/mm: Move/simplify faulthandler_disabled() and !mm check
Do the check before we re-enable interrupts and clean the code
up a bit.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/mm/fault.c')
| -rw-r--r-- | arch/powerpc/mm/fault.c | 27 |
1 files changed, 13 insertions, 14 deletions
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index 6f3a2437008a..792844559343 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -355,24 +355,23 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address, if (unlikely(!is_user && bad_kernel_fault(is_exec, error_code, address))) return SIGSEGV; + /* + * If we're in an interrupt, have no user context or are running + * in a region with pagefaults disabled then we must not take the fault + */ + if (unlikely(faulthandler_disabled() || !mm)) { + if (is_user) + printk_ratelimited(KERN_ERR "Page fault in user mode" + " with faulthandler_disabled()=%d" + " mm=%p\n", + faulthandler_disabled(), mm); + return bad_area_nosemaphore(regs, address); + } + /* We restore the interrupt state now */ if (!arch_irq_disabled_regs(regs)) local_irq_enable(); - if (faulthandler_disabled() || mm == NULL) { - if (!is_user) - return SIGSEGV; - - /* faulthandler_disabled() in user mode is really bad, - as is current->mm == NULL. */ - printk(KERN_EMERG "Page fault in user mode with " - "faulthandler_disabled() = %d mm = %p\n", - faulthandler_disabled(), mm); - printk(KERN_EMERG "NIP = %lx MSR = %lx\n", - regs->nip, regs->msr); - die("Weird page fault", regs, SIGSEGV); - } - perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); /* |