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Date: Tue, 06 Feb 2018 09:37:52 +0100
From: Oleksandr Natalenko <oleksandr@natalenko.name>
To: Mike Galbraith <efault@gmx.de>
Cc: Paolo Valente <paolo.valente@linaro.org>, Jens Axboe <axboe@kernel.dk>,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        ulf.hansson@linaro.org, broonie@kernel.org, linus.walleij@linaro.org,
        bfq-iosched@googlegroups.com, alban.browaeys@gmail.com,
        ming.lei@redhat.com, ivan@ludios.org, 169364@studenti.unimore.it,
        Serena Ziviani <ziviani.serena@gmail.com>
Subject: Re: [PATCH BUGFIX 1/1] block, bfq: add requeue-request hook
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Hi.

06.02.2018 08:56, Mike Galbraith wrote:
> I was doing kbuilds, and it blew up on me twice.  Switching back to cfq
> seemed to confirm it was indeed the patch causing trouble, but that's
> by no means a certainty.

Just to note, I was using v4.15.1, not the latest git HEAD. Are you able 
to reproduce it on the stable kernel? Also, assuming this issue might be 
unrelated to the BFQ itself, did you manage to reproduce the trouble 
with another blk-mq scheduler (not CFQ, but mq-deadline/Kyber)?

Regards,
   Oleksandr