lkml.org 
[lkml]   [2022]   [Apr]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 2/5] sched,ptrace: Fix ptrace_check_attach() vs PREEMPT_RT
On 04/20, Peter Zijlstra wrote:
>
> On Fri, Apr 15, 2022 at 12:57:56PM +0200, Oleg Nesterov wrote:
> >
> > ptrace_resume() does wake_up_state(child, __TASK_TRACED) but doesn't
> > clear JOBCTL_TRACED. The "else" branch in ptrace_stop() leaks this flag
> > too. Perhaps I missed something, I'll reread 1/5 again, but the main
> > question to me is whether 1-2 actually need the JOBCTL_TRACED_FROZEN flag.
>
> Ok, getting back to this. So I did the change to ptrace_resume(), but
> I'm not entirely sure I understand the issue with the else branch of
> ptrace_stop().
>
> My understanding is that if we hit that else branch, we've raced wth
> __ptrace_unlink(), and that will have done:

Yes, thanks for correcting me, I forgot that may_ptrace_stop() has gone.

Oleg.

\
 
 \ /
  Last update: 2022-04-20 13:36    [W:0.209 / U:0.024 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site