lkml.org 
[lkml]   [2016]   [Aug]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: ptrace group stop signal number not reset before PTRACE_INTERRUPT is delivered?
On Thu, Aug 18, 2016 at 12:23 PM, Oleg Nesterov <oleg@redhat.com> wrote:
>
> And you if you get PTRACE_EVENT_STOP and WSTOPSIG() == SIGTTIN after
> PTRACE_INTERRUPT, you know that the tracee did not report the "new"
> SIGTTIN.

It seems possible to remember whether or not we injected a stopping
signal and if so the next PTRACE_EVENT_STOP is a group-stop, otherwise
a PTRACE_INTERRUPT stop. Currently what I do is the other way around,
after issuing PTRACE_INTERRUPT, the first (if any) of the next two
stops that is a PTRACE_EVENT_STOP get interpreted as a
PTRACE_INTERRUPT stop. I haven't thought through this fully yet, so I
can't give you a concrete example I worried about, it just seems
fragile compared to just checking whether WSTOPSIG() == SIGTRAP.

\
 
 \ /
  Last update: 2016-09-17 09:57    [W:0.062 / U:0.392 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site