Author: Ingo Molnar <mingo@xxxxxxx> AuthorDate: Fri, 20 Feb 2009 23:39:02 +0100 Commit: Ingo Molnar <mingo@xxxxxxx> CommitDate: Sat, 21 Feb 2009 00:09:46 +0100 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 <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Ingo Molnar <mingo@xxxxxxx> --- arch/x86/mm/fault.c | 4 +--- 1 files changed, 1 insertions(+), 3 deletions(-) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index f195691..413e835 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; -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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