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From:   Roman Gushchin <guro@fb.com>
To:     Oleg Nesterov <oleg@redhat.com>
CC:     Roman Gushchin <guroan@gmail.com>, Tejun Heo <tj@kernel.org>,
        "cgroups@vger.kernel.org" <cgroups@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Kernel Team <Kernel-team@fb.com>
Subject: Re: [PATCH v2 3/6] cgroup: cgroup v2 freezer
Thread-Topic: [PATCH v2 3/6] cgroup: cgroup v2 freezer
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Date:   Wed, 14 Nov 2018 17:39:11 +0000
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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 befor=
e
> > > clear_thread_flag(TIF_SIGPENDING).
> >
> > So, I had TASK_KILLABLE before, but had some issues with ptrace/gdb.
> > I'll revisit this option.
>=20
> Yes, ptrace_signal_wake_up() won't wake a TASK_KILLABLE tracee up...
>=20
> 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.