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Date:   Wed, 17 May 2023 20:01:45 -0500
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Subject: Re: [RFC PATCH 2/8] vhost/vhost_task: Hook vhost layer into signal
 handler
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     oleg@redhat.com, linux@leemhuis.info, nicolas.dichtel@6wind.com,
        axboe@kernel.dk, ebiederm@xmission.com,
        linux-kernel@vger.kernel.org,
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        sgarzare@redhat.com, jasowang@redhat.com, stefanha@redhat.com,
        brauner@kernel.org
References: <20230518000920.191583-1-michael.christie@oracle.com>
 <20230518000920.191583-3-michael.christie@oracle.com>
 <CAHk-=wga+96PqV4x8EwFAMfi--m9essdX+3uPE-AoOSAQR1ddA@mail.gmail.com>
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From:   Mike Christie <michael.christie@oracle.com>
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On 5/17/23 7:16 PM, Linus Torvalds wrote:
> On Wed, May 17, 2023 at 5:09 PM Mike Christie
> <michael.christie@oracle.com> wrote:
>>
>> +       __set_current_state(TASK_RUNNING);
>> +       rc = get_signal(&ksig);
>> +       set_current_state(TASK_INTERRUPTIBLE);
>> +       return rc;
> 
> The games with current_state seem nonsensical.
> 
> What are they all about? get_signal() shouldn't care, and no other
> caller does this thing. This just seems completely random.

Sorry. It's a leftover.

I was originally calling this from vhost_task_should_stop where before
calling that function we do a:

set_current_state(TASK_INTERRUPTIBLE);

So, I was hitting get_signal->try_to_freeze->might_sleep->__might_sleep
and was getting the "do not call blocking ops when !TASK_RUNNING"
warnings.