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Date:   Thu, 18 May 2023 20:23:02 +0200
From:   Oleg Nesterov <oleg@redhat.com>
To:     Christian Brauner <brauner@kernel.org>
Cc:     Mike Christie <michael.christie@oracle.com>, linux@leemhuis.info,
        nicolas.dichtel@6wind.com, axboe@kernel.dk, ebiederm@xmission.com,
        torvalds@linux-foundation.org, linux-kernel@vger.kernel.org,
        virtualization@lists.linux-foundation.org, mst@redhat.com,
        sgarzare@redhat.com, jasowang@redhat.com, stefanha@redhat.com
Subject: Re: [RFC PATCH 1/8] signal: Dequeue SIGKILL even if
 SIGNAL_GROUP_EXIT/group_exec_task is set
Message-ID: <20230518182301.GB5817@redhat.com>
References: <20230518000920.191583-1-michael.christie@oracle.com>
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 <7412912a-a470-bd3d-fb1c-54c094cc01ee@oracle.com>
 <20230518-ratgeber-erbeben-843e68b0d6ac@brauner>
 <20230518180809.GA5817@redhat.com>
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On 05/18, Christian Brauner wrote:
>
> On Thu, May 18, 2023 at 08:08:10PM +0200, Oleg Nesterov wrote:
> > On 05/18, Christian Brauner wrote:
> > >
> > > Yeah, but these are issues that exist with PF_IO_WORKER then too
> >
> > This was my thought too but I am starting to think I was wrong.
> >
> > Of course I don't understand the code in io_uring/ but it seems
> > that it always breaks the IO loops if get_signal() returns SIGKILL.
>
> Yeah, it does and I think Mike has a point that vhost could be running
> into an issue here that io_uring currently does avoid. But I don't think
> we should rely on that.

So what do you propose?

Unless (quite possibly) I am confused again, unlike io_uring vhost can't
tolerate signal_pending() == T in the cleanup-after-SIGKILL paths?

Oleg.