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Bug 1226621

Summary: WARNING: CPU: 1 PID: 2236 at mm/backing-dev.c:372 bdi_unregister+0x3a/0x50()
Product: [Fedora] Fedora Reporter: poma <pomidorabelisima>
Component: kernelAssignee: Kernel Maintainer List <kernel-maint>
Status: CLOSED ERRATA QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 22CC: gansalmon, itamar, jonathan, kernel-maint, madhu.chinakonda, mchehab
Target Milestone: ---   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: kernel-4.0.5-300.fc22 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2015-06-20 23:58:28 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description poma 2015-05-31 08:13:58 UTC 
Induced via the 'liveinst' (anaconda-core):

[  579.507546] ------------[ cut here ]------------
[  579.507566] WARNING: CPU: 1 PID: 2236 at mm/backing-dev.c:372 bdi_unregister+0x3a/0x50()
[  579.507570] Modules linked in: ...
[  579.507788] CPU: 1 PID: 2236 Comm: kworker/1:0 Not tainted 4.0.4-301.fc22.x86_64 #1
[  579.507807] Workqueue: md_misc mddev_delayed_delete
...
[  579.507833] Call Trace:
[  579.507847]  [<ffffffff81782644>] dump_stack+0x45/0x57
[  579.507855]  [<ffffffff8109c66a>] warn_slowpath_common+0x8a/0xc0
[  579.507862]  [<ffffffff8109c79a>] warn_slowpath_null+0x1a/0x20
[  579.507870]  [<ffffffff811c0a4a>] bdi_unregister+0x3a/0x50
[  579.507880]  [<ffffffff8137f5c1>] del_gendisk+0x131/0x240
[  579.507888]  [<ffffffff815e6853>] md_free+0x43/0x60
[  579.507904]  [<ffffffff8139e44a>] kobject_release+0x7a/0x1c0
[  579.507911]  [<ffffffff8139e2f5>] kobject_put+0x35/0x70
[  579.507918]  [<ffffffff815e4794>] mddev_delayed_delete+0x34/0x40
[  579.507925]  [<ffffffff810b596b>] process_one_work+0x1bb/0x410
[  579.507932]  [<ffffffff810b5c13>] worker_thread+0x53/0x470
[  579.507939]  [<ffffffff810b5bc0>] ? process_one_work+0x410/0x410
[  579.507945]  [<ffffffff810b5bc0>] ? process_one_work+0x410/0x410
[  579.507952]  [<ffffffff810bb678>] kthread+0xd8/0xf0
[  579.507960]  [<ffffffff810bb5a0>] ? kthread_worker_fn+0x180/0x180
[  579.507969]  [<ffffffff81788bd8>] ret_from_fork+0x58/0x90
[  579.507977]  [<ffffffff810bb5a0>] ? kthread_worker_fn+0x180/0x180
[  579.507982] ---[ end trace b8bdede9e26ccf5c ]---


http://thread.gmane.org/gmane.linux.kernel/1956706
https://lkml.org/lkml/2015/5/21/832

[PATCH v2 RESEND] block: discard bdi_unregister() in favour of bdi_destroy()
https://patchwork.kernel.org/patch/6433411/

I already drive a kernel with this patch - 4.0.4-507.fc22.x86_64.
So far so good.
Comment 1 poma 2015-05-31 22:41:30 UTC 
https://bugzilla.kernel.org/show_bug.cgi?id=99271
Comment 2 Josh Boyer 2015-06-04 11:47:00 UTC 
Upstream as aad653a0bc09dd4ebcb5579f9f835bbae9ef2ba3 now.  Backported to f20-f22 branches.  Thank you.
Comment 3 poma 2015-06-08 11:14:33 UTC 
mainline: 4.1-rc7:

https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/diff/block/genhd.c?id=v4.1-rc7&id2=v4.1-rc6
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/diff/include/linux/backing-dev.h?id=v4.1-rc7&id2=v4.1-rc6
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/diff/include/trace/events/writeback.h?id=v4.1-rc7&id2=v4.1-rc6
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/diff/mm/backing-dev.c?id=v4.1-rc7&id2=v4.1-rc6
Comment 4 Fedora Update System 2015-06-09 12:57:56 UTC 
kernel-4.0.5-300.fc22 has been submitted as an update for Fedora 22.
https://admin.fedoraproject.org/updates/kernel-4.0.5-300.fc22
Comment 5 Fedora Update System 2015-06-09 12:59:27 UTC 
kernel-4.0.5-200.fc21 has been submitted as an update for Fedora 21.
https://admin.fedoraproject.org/updates/kernel-4.0.5-200.fc21
Comment 6 Fedora Update System 2015-06-10 19:09:00 UTC 
Package kernel-4.0.5-200.fc21:
* should fix your issue,
* was pushed to the Fedora 21 testing repository,
* should be available at your local mirror within two days.
Update it with:
# su -c 'yum update --enablerepo=updates-testing kernel-4.0.5-200.fc21'
as soon as you are able to, then reboot.
Please go to the following url:
https://admin.fedoraproject.org/updates/FEDORA-2015-9704/kernel-4.0.5-200.fc21
then log in and leave karma (feedback).
Comment 7 Fedora Update System 2015-06-20 23:58:28 UTC 
kernel-4.0.5-200.fc21 has been pushed to the Fedora 21 stable repository.  If problems still persist, please make note of it in this bug report.
Comment 8 Fedora Update System 2015-06-21 00:31:49 UTC 
kernel-4.0.5-300.fc22 has been pushed to the Fedora 22 stable repository.  If problems still persist, please make note of it in this bug report.