On 05/18, Miroslav Benes wrote: > > On Thu, 18 May 2017, Oleg Nesterov wrote: > > > > > exit_to_usermode_loop() calls do_signal(), then klp_update_patch_state(). > > So it won't be cleared here. > > Ok, so maybe I misunderstand the code. I see the loop in > exit_to_usermode_loop() for processing ALLWORK_MASK. There we call > do_signal(). We go to get_signal(). The infinite loop there is relevant > for us. We call dequeue_signal(). There, if I am not mistaken > __dequeue_signal() would return 0 Yes, sorry, I didn't bother to read the code when I looked at your patch and my memory fooled me. > If not, we get back to exit_to_usermode_loop() and TIF_PATCH_PENDING is > cleared. Yes, it is true that TIF_SIGPENDING is still set and we get to > do_signal() once more. But for the last time. Yes, slightly sub-optimal but not really wrong and you can swap do_signal() and klp_update_patch_state(). > If the syscall is restarted, it may be different. I have to think about > this one. But... Afaics, there are no problems. In short. Thanks for correcting me and sorry for noise! Oleg. -- To unsubscribe from this list: send the line "unsubscribe live-patching" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
