On 05/24, Deepa Dinamani wrote: > > I think you are misunderstanding what I said. probably. Everything was very confusing to me from the very beginning. And yes, I can hardly understand your emails, sorry. This one too :/ > You are taking things > out of context. I was saying here what I did was inspired by why the > syscall was designed to begin with. which syscall? > The syscall below refers to > epoll_wait and not epoll_pwait. So you tried to explain why epoll_pwait() was designed? Or what? Either way, everything I said below still looks right to me. This probably means that I still can't understand you. But this is irrelevant. My main point is that the kernel was correct before 854a6ed568 ("signal: Add restore_user_sigmask()"), the (incomplete) patch I sent tries to a) restore the correct behaviour and b) simplify/cleanup the code. > On Fri, May 24, 2019 at 7:19 AM Oleg Nesterov <oleg@xxxxxxxxxx> wrote: > > > > On 05/23, Deepa Dinamani wrote: > > > > > > 1. block the signals you don't care about. > > > 2. syscall() > > > 3. unblock the signals blocked in 1. > > > > and even this part of your email is very confusing. because in this case > > we can never miss a signal. I'd say > > > > 1. block the signals you don't care about > > 2. unblock the signals which should interrupt the syscall below > > 3. syscall() > > 4. block the signals unblocked in 2. > > > > Oleg. > >