linux-kernel - Re: [RFC 5/5] pm: remove kernel thread freezing

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Message-ID: <nycvar.YFH.7.76.1710032223170.17517@jbgna.fhfr.qr>
Date:   Tue, 3 Oct 2017 22:24:51 +0200 (CEST)
From:   Jiri Kosina <jikos@...nel.org>
To:     Bart Van Assche <Bart.VanAssche@....com>
cc:     "boris.ostrovsky@...cle.com" <boris.ostrovsky@...cle.com>,
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Subject: Re: [RFC 5/5] pm: remove kernel thread freezing

On Tue, 3 Oct 2017, Bart Van Assche wrote:

> If just a single driver would use that API to prevent that I/O occurs while
> processes are frozen then this patch will break that driver. I would like to
> know your opinion about the following patch in particular: "[PATCH v4 1/7] md:
> Make md resync and reshape threads freezable"
> (https://www.spinics.net/lists/linux-block/msg17854.html).

Alright, if there are kthreads which are actually *creating* new I/O 
(contrary to kthreads being I/O completion helpers) -- which apparently is 
the md case here, then those definitely have to be frozen in some form.

-- 
Jiri Kosina
SUSE Labs