From: Ingo Molnar Date: Fri, 20 Feb 2009 22:39:02 +0000 (+0100) Subject: x86, mm: fault.c, give another attempt at prefetch handing before SIGBUS X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=cd1b68f08f6328737928e5b8ba8ef80394680ff0;p=linux-beck.git x86, mm: fault.c, give another attempt at prefetch handing before SIGBUS Impact: extend prefetch handling on 64-bit Currently there's an extra is_prefetch() check done in do_sigbus(), which we only do on 32 bits. This is a last-ditch check before we terminate a task, so it's worth giving prefetch instructions another chance - should none of our existing quirks have caught a prefetch instruction related spurious fault. The only risk is if a prefetch causes a real sigbus, in that case we'll not OOM but try another fault. But this code has been on 32-bit for a long time, so it should be fine in practice. So do this on 64-bit too - and thus remove one more #ifdef. Cc: Linus Torvalds Signed-off-by: Ingo Molnar --- diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index f195691ec26e..413e835e4a80 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -836,11 +836,9 @@ do_sigbus(struct pt_regs *regs, unsigned long error_code, unsigned long address) if (!(error_code & PF_USER)) no_context(regs, error_code, address); -#ifdef CONFIG_X86_32 - /* User space => ok to do another page fault: */ + /* User-space => ok to do another page fault: */ if (is_prefetch(regs, error_code, address)) return; -#endif tsk->thread.cr2 = address; tsk->thread.error_code = error_code;