----- On May 14, 2020, at 10:17 AM, Borislav Petkov [email protected] wrote: > + Tony. > > On Tue, May 05, 2020 at 03:16:31PM +0200, Thomas Gleixner wrote: >> From: Peter Zijlstra <[email protected]> >> >> Convert #MC over to using task_work_add(); it will run the same code >> slightly later, on the return to user path of the same exception. >> >> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> >> Signed-off-by: Thomas Gleixner <[email protected]> >> Reviewed-by: Frederic Weisbecker <[email protected]> >> --- >> arch/x86/kernel/cpu/mce/core.c | 56 >> ++++++++++++++++++++++------------------- >> include/linux/sched.h | 6 ++++ >> 2 files changed, 37 insertions(+), 25 deletions(-) > > I like this: > > Reviewed-by: Borislav Petkov <[email protected]>
What I am not fully grasping here is whether this patch preserves the instruction pointer (and possibly other relevant information for siginfo_t) triggering the exception in a scenario where we have: - #MC triggered, queuing task work, - unrelated signal happens to be delivered to task, - exit to usermode loop handles do_signal first, - then it runs task work. Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com
