lkml.org 
[lkml]   [2016]   [Sep]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [writeback] 8bc4ad9498: INFO: suspicious RCU usage. ]
On Thu, Sep 01, 2016 at 06:21:30PM +0800, kernel test robot wrote:
>
> FYI, we noticed the following commit:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git wb-buf-throttle
> commit 8bc4ad9498f81d6689da42457615db0989e720d3 ("writeback: throttle buffered writeback")
>
> in testcase: boot
>
> on test machine: qemu-system-x86_64 -enable-kvm -cpu Westmere -m 512M
>
> caused below changes:
>
>
> +--------------------------------------+------------+------------+
> | | b2e4e4e34d | 8bc4ad9498 |
> +--------------------------------------+------------+------------+
> | boot_successes | 6 | 0 |
> | boot_failures | 0 | 8 |
> | INFO:suspicious_RCU_usage | 0 | 8 |
> | message:INFO:suspicious_RCU_usage | 0 | 0.0 |
> | pattern:INFO:suspicious_RCU_usage | 0 | 0 |
> | calltrace:disk_events_workfn | 0 | 8 |
> | message:calltrace:disk_events_workfn | 0 | 0.0 |
> | pattern:calltrace:disk_events_workfn | 0 | 0 |
> +--------------------------------------+------------+------------+
>
>
>
> [ 7.389264] stack backtrace:
> [ 7.391300] CPU: 0 PID: 19 Comm: kworker/0:1 Not tainted 4.8.0-rc4-00008-g8bc4ad9 #1
> [ 7.395279] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014
> [ 7.398012] Workqueue: events_freezable_power_ disk_events_workfn
> [ 7.399933] 0000000000000000 ffff88003db1f8e8 ffffffff8178ed3b ffff88003db184c0
> [ 7.404348] 0000000000000001 ffff88003db1f918 ffffffff81123472 ffff88003db184c0
> [ 7.407158] ffffffff84091180 0000000000000003 ffff880039d4c400 ffff88003db1f938
> [ 7.410074] Call Trace:
> [ 7.411328] [<ffffffff8178ed3b>] dump_stack+0x82/0xb8
> [ 7.413982] [<ffffffff81123472>] lockdep_rcu_suspicious+0xf7/0x100
> [ 7.415828] [<ffffffff817873f4>] bio_blkcg+0x89/0x93
> [ 7.417336] [<ffffffff817891f0>] check_blkcg_changed+0x58/0x1b8

Hmm... can't reproduce here on qemu with v4.8-rc5 and the same kernel
config. Can you please check whether it reproduces on v4.8-rc5? If
so, is there any way I can get the qemu image and command line used?

Thanks.

--
tejun

\
 
 \ /
  Last update: 2016-09-17 09:58    [W:0.106 / U:0.148 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site