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Date:   Mon, 29 May 2023 11:11:43 -0500
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Subject: Re: [PATCH 3/3] fork, vhost: Use CLONE_THREAD to fix freezer/ps
 regression
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To:     Oleg Nesterov <oleg@redhat.com>,
        "Eric W. Biederman" <ebiederm@xmission.com>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        linux@leemhuis.info, nicolas.dichtel@6wind.com, axboe@kernel.dk,
        linux-kernel@vger.kernel.org,
        virtualization@lists.linux-foundation.org, mst@redhat.com,
        sgarzare@redhat.com, jasowang@redhat.com, stefanha@redhat.com,
        brauner@kernel.org
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On 5/29/23 6:19 AM, Oleg Nesterov wrote:
> If we want CLONE_THREAD, I think vhost_worker() should exit after get_signal()
> returns SIGKILL. Perhaps it should "disable" vhost_work_queue() somehow and
> flush the pending works on ->work_list before exit, I dunno. But imo it should
> not wait for the final fput().

Just a FYI, I coded this. It's pre-RFC quality. It's invasive. If we want to go
this route then we have to do a temp hack for 6.4 or revert then do this route
for 6.5 or 6.6 (vhost devs will need time to review and we need time to full test).