linux-kernel - Re: bug in tag handling in blk-mq?

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <3692ce7d-a767-72e6-65ae-6178b6c2e7d8@kernel.dk>
Date:   Tue, 8 May 2018 14:37:52 -0600
From:   Jens Axboe <axboe@...nel.dk>
To:     Mike Galbraith <efault@....de>,
        Paolo Valente <paolo.valente@...aro.org>
Cc:     Christoph Hellwig <hch@....de>,
        linux-block <linux-block@...r.kernel.org>,
        Ulf Hansson <ulf.hansson@...aro.org>,
        LKML <linux-kernel@...r.kernel.org>,
        Linus Walleij <linus.walleij@...aro.org>,
        Oleksandr Natalenko <oleksandr@...alenko.name>
Subject: Re: bug in tag handling in blk-mq?

On 5/8/18 10:42 AM, Mike Galbraith wrote:
> On Tue, 2018-05-08 at 08:55 -0600, Jens Axboe wrote:
>>
>> All the block debug files are empty...
> 
> Sigh.  Take 2, this time cat debug files, having turned block tracing
> off before doing anything else (so trace bits in dmesg.txt should end
> AT the stall).

OK, that's better. What I see from the traces:

- You have regular IO and some non-fs IO (from scsi_execute()). This mix
  may be key.

- sdd has nothing pending, yet has 6 active waitqueues.

I'm going to see if I can reproduce this. Paolo, what kind of attempts
to reproduce this have you done?

-- 
Jens Axboe