Subject: signal: Revert ptrace preempt magic From: Thomas Gleixner Date: Wed, 21 Sep 2011 19:57:12 +0200 Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.25-rt16.tar.xz Upstream commit '53da1d9456fe7f8 fix ptrace slowness' is nothing more than a bandaid around the ptrace design trainwreck. It's not a correctness issue, it's merily a cosmetic bandaid. Signed-off-by: Thomas Gleixner --- kernel/signal.c | 8 -------- 1 file changed, 8 deletions(-) --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2094,15 +2094,7 @@ static void ptrace_stop(int exit_code, i if (gstop_done && ptrace_reparented(current)) do_notify_parent_cldstop(current, false, why); - /* - * Don't want to allow preemption here, because - * sys_ptrace() needs this task to be inactive. - * - * XXX: implement read_unlock_no_resched(). - */ - preempt_disable(); read_unlock(&tasklist_lock); - preempt_enable_no_resched(); freezable_schedule(); } else { /*