On Thu, Sep 24, 2026 at 12:11:31PM +0800, Jinjie Ruan wrote:
>
>
> 在 2026/9/23 3:57, Kees Cook 写道:
> > ptrace(2) states that no syscall-exit-stop occurs when a tracee is
> > continued with PTRACE_SYSEMU or PTRACE_SYSEMU_SINGLESTEP. arm64 gated
> > its syscall-exit report on
> >
> > flags & (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP)
>
> Hi Kees,
>
> The original fix description is a bit off: on arm64 there is no extra
> syscall-exit-stop; instead, there's an additional pseudo single-step
> injection.
>
> As sashiko pointed out, as commit ac2081cdc4d9 ("arm64: ptrace:
> Consistently use pseudo-singlestep exceptions") described, for
> PTRACE_SYSEMU_SINGLESTEP, arm64 still needs the pseudo single-step
> because its hardware single-step state machine is fast-forwarded over
> the SVC instruction.
Ah! Okay. So this test should be tweaked to deal with that? Feel free to
snag/update this test for the series. We didn't have anything testing
syscall exit stops, so it seemed reasonable to get it written.
-Kees
--
Kees Cook
