Bug 9495

Summary: [2.6.24 BUG] 100% iowait on host while UML is running
Product: Platform Specific/Hardware Reporter: Rafael J. Wysocki (rjwysocki)
Component: UMLAssignee: Jeff Dike (jdike)
Status: CLOSED CODE_FIX    
Severity: normal    
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: 2.6.24-rc Subsystem:
Regression: Yes Bisected commit-id:
Bug Depends on:    
Bug Blocks: 9243    

Description Rafael J. Wysocki 2007-12-03 13:25:51 UTC 
Subject         : [2.6.24 BUG] 100% iowait on host while UML is running
Submitter       : Miklos Szeredi <miklos@szeredi.hu>
References      : http://lkml.org/lkml/2007/12/3/119
Handled-By      : Jeff Moyer <jmoyer@redhat.com>
Patch           : http://lkml.org/lkml/2007/12/3/192
Comment 1 Rafael J. Wysocki 2007-12-03 13:27:04 UTC 
Caused by:

commit 41d10da3717409de33d5441f2f6d8f072ab3fbb6
Author: Jeff Moyer <jmoyer@redhat.com>
Date:   Tue Oct 16 23:27:20 2007 -0700

    aio: account I/O wait time properly

http://git.kernel.org/gitweb.cgi?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=41d10da3717409de33d5441f2f6d8f072ab3fbb6
Comment 2 Rafael J. Wysocki 2007-12-07 17:51:45 UTC 
Fixed by:

commit e00ba3dae077f54cfd2af42e939a618caa7a3bca
Author: Jeff Moyer <jmoyer@redhat.com>
Date:   Tue Dec 4 23:45:02 2007 -0800

    aio: only account I/O wait time in read_events if there are active requests

http://git.kernel.org/gitweb.cgi?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=e00ba3dae077f54cfd2af42e939a618caa7a3bca