Bug 691892

Summary:	DM target crashes on unbound loop device
Product:	[Fedora] Fedora	Reporter:	Zdenek Kabelac <zkabelac>
Component:	device-mapper	Assignee:	Milan Broz <mbroz>
Status:	CLOSED RAWHIDE	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	rawhide	CC:	agk, bmarzins, dwysocha, extras-orphan, heinzm, jonathan, mbroz, prockai, pvrabec
Target Milestone:	---
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Hardware:	Unspecified
OS:	Unspecified
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Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2012-03-22 16:24:41 UTC	Type:	---
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Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:

Description Zdenek Kabelac 2011-03-29 19:48:46 UTC

Description of problem:

Kernel is oopsing when unbound loop devices is used for mirror setup.
i.e.:
dmsetup create x --table "0 8 mirror core 2 8 sync 2 /dev/loop0 0 /dev/loop1 0"

and mirror resync will immediatelly cause OOps.

BUG: unable to handle kernel NULL pointer dereference at   (null)
 ? generic_make_request+0x2bd/0x590
 ? kmem_cache_alloc+0xad/0x190
 submit_bio+0x53/0xe0
 ? bio_add_page+0x3b/0x50
 dispatch_io+0x1ca/0x210 [dm_mod]
 ? read_callback+0x0/0xd0 [dm_mirror]
 dm_io+0xbb/0x290 [dm_mod]
 do_mirror+0x1e0/0x748 [dm_mirror]


Version-Release number of selected component (if applicable):
kernel 2.6.38 and earlier

How reproducible:


Steps to Reproduce:
1.
2.
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Actual results:


Expected results:


Additional info:

Comment 1 Zdenek Kabelac 2011-03-29 19:51:32 UTC

Patch posted by Milan on device-mapper devel list:

https://www.redhat.com/archives/dm-devel/2011-March/msg00146.html

Comment 2 Milan Broz 2012-03-22 16:24:41 UTC

Fixed upstream, thus even in rawhide.

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=f4808ca99a203f20b4475601748e44b25a65bdec