From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jes Sorensen <Jes.Sorensen@redhat.com>
Subject: Re: md_raid5 using 100% CPU and hang with status resync=PENDING, if a drive is removed during initialization
Date: Mon, 16 Feb 2015 17:49:57 -0500
Message-ID: <wrfjd259o4iy.fsf@redhat.com>
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In-Reply-To: <wrfjpp99pp9d.fsf@redhat.com> (Jes Sorensen's message of "Mon, 16
	Feb 2015 15:36:46 -0500")
Sender: linux-raid-owner@vger.kernel.org
To: NeilBrown <neilb@suse.de>
Cc: Manibalan P <pmanibalan@amiindia.co.in>, Pasi =?utf-8?B?S8Okcmtrw6Rp?= =?utf-8?B?bmVu?= <pasik@iki.fi>, linux-raid <linux-raid@vger.kernel.org>
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Jes Sorensen <Jes.Sorensen@redhat.com> writes:
> NeilBrown <neilb@suse.de> writes:
>> On Mon, 2 Feb 2015 07:10:14 +0000 Manibalan P <pmanibalan@amiindia.co.in>
>> wrote:
>>
>>> Dear All,
>>> 	Any updates on this issue.
>>
>> Probably the same as:
>>
>>   http://marc.info/?l=linux-raid&m=142283560704091&w=2
>
> Hi Neil,
>
> I ran some tests on this one against the latest Linus' tree as of today
> (1fa185ebcbcefdc5229c783450c9f0439a69f0c1) which I believe includes all
> your pending 3.20 patches.
>
> I am able to reproduce Manibalan's hangs on a system with 4 SSDs if I
> run fio on top of a device while it is resyncing and I fail one of the
> devices.

Since Manibalan mentioned this issue wasn't present in earlier kernels,
I started trying to track down what change caused it.

So far I have been able to reproduce the hang as far back as 3.10.

Cheers,
Jes