Re: [PATCH] entry: Fix missed trap after single-step on system call return

[Linus Torvalds]

On Wed, Feb 3, 2021 at 10:18 AM Andy Lutomirski <luto@xxxxxxxxxx> wrote:
>
> So if we want to reliably single-step a system call and trap after the
> system call, we just need to synthesize a trap on the way out.

Well, I think Gabriel's patch does exactly that, due to how
SYSCALL_EXIT_TRAP is set. It looks like subsequent system calls will
work exactly the way the concurrent system call case (that Kyle's test
did) does.

So it all _looks_ sane to me, but this is one of those "it needs testing".

               Linus