Bug 247879

Summary:	dm-mirror: spinlock in write_callback has the potential for deadlock
Product:	Red Hat Enterprise Linux 4	Reporter:	Jonathan Earl Brassow <jbrassow>
Component:	kernel	Assignee:	Jonathan Earl Brassow <jbrassow>
Status:	CLOSED ERRATA	QA Contact:	Martin Jenner <mjenner>
Severity:	low	Docs Contact:
Priority:	low
Version:	4.5	CC:	jbaron, lvm-team
Target Milestone:	---
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	RHSA-2008-0665	Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2008-07-24 19:13:44 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	247877
Bug Blocks:	430698

Description Jonathan Earl Brassow 2007-07-11 20:16:54 UTC

+++ This bug was initially created as a clone of Bug #247877 +++

write_callback is in dm-raid1.c is called when an I/O completes.  It calls
spin_lock(&ms->lock).  Since write_callback could be called from either process
or interrupt context, we need to use spin_lock_irqsave().

This becomes especially important when we want to layer dm-targets that might
call bio_endio from process context.

Comment 1 RHEL Program Management 2007-08-13 14:11:47 UTC

This request was evaluated by Red Hat Product Management for inclusion in a Red
Hat Enterprise Linux maintenance release.  Product Management has requested
further review of this request by Red Hat Engineering, for potential
inclusion in a Red Hat Enterprise Linux Update release for currently deployed
products.  This request is not yet committed for inclusion in an Update
release.

Comment 3 Linda Wang 2007-09-21 16:34:23 UTC

since the patch was posted after 4.6 kernel freeze, this patch requires
justfication to bring into 4.6 after the deadline.  Please provide bussiness
or technical justification and set either blocker or exception flag below to "?"
for 4.6 consideration.

Comment 4 Linda Wang 2007-09-25 22:27:58 UTC

okay.. move to 4.7. please provide bus./tech. justification for
4.6 inclusion if need to.

Comment 5 Vivek Goyal 2008-01-23 00:12:50 UTC

Committed in 68.8

Comment 9 errata-xmlrpc 2008-07-24 19:13:44 UTC

An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on therefore solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHSA-2008-0665.html