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Date:   Tue, 28 Apr 2020 21:08:37 +0200
From:   Oleg Nesterov <oleg@redhat.com>
To:     Linus Torvalds <torvalds@linux-foundation.org>,
        Jann Horn <jannh@google.com>
Cc:     Bernd Edlinger <bernd.edlinger@hotmail.de>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        Waiman Long <longman@redhat.com>,
        Ingo Molnar <mingo@kernel.org>, Will Deacon <will@kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Alexey Gladkov <gladkov.alexey@gmail.com>
Subject: Re: [GIT PULL] Please pull proc and exec work for 5.7-rc1
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On 04/28, Linus Torvalds wrote:
>
> On Mon, Apr 27, 2020 at 7:56 PM Bernd Edlinger
> <bernd.edlinger@hotmail.de> wrote:
> >
> > was this resolved meanwhile?
>
> No. I think the tentative plan is to just apply Oleg's "don't wait for
> zombie threads with cred_guard_mutex held" patch, hopefully with that
> de_thread() moved into install_exec_creds() (right after the dropping
> of the locks).

Oops. I can update that old patch but somehow I thought there is a better
plan which I don't yet understand...

And, IIRC, Jan had some ideas how to rework the new creds calculation in
execve paths to avoid the cred_guard_mutex deadlock?

Oleg.