Re: [PATCH v2 3/6] cgroup: cgroup v2 freezer

From: Roman Gushchin
Date: Wed Nov 14 2018 - 12:39:23 EST


On Wed, Nov 14, 2018 at 06:36:11PM +0100, Oleg Nesterov wrote:
> On 11/14, Roman Gushchin wrote:
> >
> > > No, this is very wrong. Just suppose the caller is killed right before
> > > clear_thread_flag(TIF_SIGPENDING).
> >
> > So, I had TASK_KILLABLE before, but had some issues with ptrace/gdb.
> > I'll revisit this option.
>
> Yes, ptrace_signal_wake_up() won't wake a TASK_KILLABLE tracee up...
>
> BTW. Could you explain in the changelog how should a frozen task interact
> with ptrace? 0/6 says "ptrace works" but that is all. It is not clear to me
> what do we actually want wrt ptrace...

Sure, will add.
Basically, I want some minimal functionality to work properly.
E.g. attach to a frozen task, get some info, detach.