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Subject: Re: [PATCH] livepatch: klp_send_signal should treat PF_IO_WORKER like
 PF_KTHREAD
To:     Miroslav Benes <mbenes@suse.cz>,
        Joe Lawrence <joe.lawrence@redhat.com>
Cc:     Dong Kai <dongkai11@huawei.com>, jpoimboe@redhat.com,
        jikos@kernel.org, pmladek@suse.com, live-patching@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20210325014836.40649-1-dongkai11@huawei.com>
 <cd701421-f2c6-56f6-5798-106bc9de0084@redhat.com>
 <alpine.LSU.2.21.2103251026180.30447@pobox.suse.cz>
From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <f4969563-23fa-cb49-8243-d600f1bf0b23@kernel.dk>
Date:   Thu, 25 Mar 2021 10:30:37 -0600
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On 3/25/21 3:30 AM, Miroslav Benes wrote:
>> (PF_KTHREAD | PF_IO_WORKER) is open coded in soo many places maybe this is a
>> silly question, but...
>>
>> If the livepatch code could use fake_signal_wake_up(), we could consolidate
>> the pattern in klp_send_signals() with the one in freeze_task().  Then there
>> would only one place for wake up / fake signal logic.
>>
>> I don't fully understand the differences in the freeze_task() version, so I
>> only pose this as a question and not v2 request.
> 
> The plan was to remove our live patching fake signal completely and use 
> the new infrastructure Jens proposed in the past.

That would be great, I've actually been waiting for that to show up!
I would greatly prefer this approach if you deem it suitable for 5.12,
if not we'll still need the temporary work-around for live patching.

-- 
Jens Axboe