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Subject: Re: kernel hangs during balance
To: Chris Murphy <lists@colorremedies.com>,
        Rich Rauenzahn <rrauenza@gmail.com>,
        Btrfs BTRFS <linux-btrfs@vger.kernel.org>
Cc: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
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Date: Wed, 20 Dec 2017 20:58:14 +0100
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On 12/20/17 20:02, Chris Murphy wrote:
> I don't know if it's the sending MUA or the list server, but the line
> wrapping makes this much harder to follow. I suggest putting it in a
> text file and attaching the text file. It's definitely not on the
> receiving side, I see it here also:
> https://www.spinics.net/lists/linux-btrfs/msg72872.html

You can see enough to suggest that blk-mq is hanging, which is
"unsurprising" (being kind here) with such an old kernel.
Rich, build your kernel with CONFIG_SCSI_MQ_DEFAULT=n or
boot with scsi_mod.use_blk_mq=n as kernel prarameter.

-h