lkml.org 
[lkml]   [2021]   [Dec]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [syzbot] general protection fault in set_task_ioprio
From
Date
On 12/21/21 3:44 AM, Eric Dumazet wrote:
> On Tue, Dec 21, 2021 at 1:52 AM syzbot
> <syzbot+8836466a79f4175961b0@syzkaller.appspotmail.com> wrote:
>>
>> syzbot has bisected this issue to:
>>
>> commit e4b8954074f6d0db01c8c97d338a67f9389c042f
>> Author: Eric Dumazet <edumazet@google.com>
>> Date: Tue Dec 7 01:30:37 2021 +0000
>>
>> netlink: add net device refcount tracker to struct ethnl_req_info
>>
>
> Unfortunately this commit will be in the way of many bisections.
>
> Real bug was added in
>
> commit 5fc11eebb4a98df5324a4de369bb5ab7f0007ff7
> Author: Christoph Hellwig <hch@lst.de>
> Date: Thu Dec 9 07:31:29 2021 +0100
>
> block: open code create_task_io_context in set_task_ioprio
>
> The flow in set_task_ioprio can be simplified by simply open coding
> create_task_io_context, which removes a refcount roundtrip on the I/O
> context.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: Jan Kara <jack@suse.cz>
> Link: https://lore.kernel.org/r/20211209063131.18537-10-hch@lst.de
> Signed-off-by: Jens Axboe <axboe@kernel.dk>

There are only really 5 patches in between the broken commit and the one
that fixes it, and it only affects things trying to set the ioprio with
a dead task. Is this a huge issue? I don't see why this would cause a
lot of bisection headaches.

--
Jens Axboe

\
 
 \ /
  Last update: 2021-12-21 16:26    [W:0.101 / U:0.016 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site