On Fri, Jan 17, 2014 at 10:10 AM, Waiman Long <[email protected]> wrote: > On 01/16/2014 08:39 AM, tip-bot for Peter Zijlstra wrote: >> >> Commit-ID: c026b3591e4f2a4993df773183704bb31634e0bd >> Gitweb: >> http://git.kernel.org/tip/c026b3591e4f2a4993df773183704bb31634e0bd >> Author: Peter Zijlstra<[email protected]> >> AuthorDate: Fri, 10 Jan 2014 21:06:03 +0100 >> Committer: Ingo Molnar<[email protected]> >> CommitDate: Thu, 16 Jan 2014 09:19:48 +0100 >> >> x86, mm, perf: Allow recursive faults from interrupts >> >> Waiman managed to trigger a PMI while in a emulate_vsyscall() fault, >> the PMI in turn managed to trigger a fault while obtaining a stack >> trace. This triggered the sig_on_uaccess_error recursive fault logic >> and killed the process dead. >> >> Fix this by explicitly excluding interrupts from the recursive fault >> logic. >> >> Reported-and-Tested-by: Waiman Long<[email protected]> >> Fixes: e00b12e64be9 ("perf/x86: Further optimize copy_from_user_nmi()") >> Cc: Aswin Chandramouleeswaran<[email protected]> >> Cc: Scott J Norton<[email protected]> >> Cc: Linus Torvalds<[email protected]> >> Cc: Andy Lutomirski<[email protected]> >> Cc: Arnaldo Carvalho de Melo<[email protected]> >> Cc: Andrew Morton<[email protected]> >> Signed-off-by: Peter Zijlstra<[email protected]> >> Link: >> http://lkml.kernel.org/r/[email protected] >> Signed-off-by: Ingo Molnar<[email protected]> >> --- >> arch/x86/mm/fault.c | 18 ++++++++++++++++++ >> 1 file changed, 18 insertions(+) >> >> > > Will that be picked up by Linus as it is a 3.13 regression?
Does anyone actually know why this regressed recently? The buggy code has been there for quite a while. --Andy -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
