Bug 697499

Summary:	SML bug: IO stalls until other mounted disk's file system becomes read-only.
Product:	Red Hat Enterprise Linux 5	Reporter:	rahul <rahulrgupta27>
Component:	kernel	Assignee:	Red Hat Kernel Manager <kernel-mgr>
Status:	CLOSED WONTFIX	QA Contact:	Red Hat Kernel QE team <kernel-qe>
Severity:	high	Docs Contact:
Priority:	unspecified
Version:	5.8	CC:	pm-rhel, rahulrgupta27
Target Milestone:	rc
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2014-06-03 12:27:07 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:

Description rahul 2011-04-18 13:17:08 UTC

Description of problem:
I am not sure whether component/category of bug is right or not. But seems to be related to SML. 
While running io (say using iozone -a) on two disks, if one disk is disconnected/pulled out/failed, IO stops on both disk until pulled disk's file system becomes read only.

Version-Release number of selected component (if applicable):


How reproducible:


Steps to Reproduce:
1. Connect two SATA HDD to mother board and boot into RHEL5asu5.
2. Format disk in ext3 fs, and mount both disk:-
mount /dev/sdb /mnt
mount /dev/sdc /media
3. Now run iozone -a on both the disks.
4. While io is running disconnect (pull out) only one disk.
5. Now both the disk io stops until one of the file system (ie sdb/mnt or sdc/media) becomes read only.

  
Actual results:
IO on both /mnt and /media stops, until one of them becomes read only file system, after one mount point has become read only, the IO on other resumes.

Expected results:
IO on one of /mnt or /media should stop, whereas other should continue without any problem, as only one disk is disconnected not both!

Additional info:

Comment 1 Andy Grover 2011-10-04 05:23:01 UTC

what is SML?

Comment 2 rahul 2011-10-04 09:06:45 UTC

(In reply to comment #1)
> what is SML?

SCSI Mid Layer.

Comment 3 Andy Grover 2011-10-10 17:28:34 UTC

-> kernel, local disk only

Comment 4 RHEL Program Management 2014-03-07 13:42:29 UTC

This bug/component is not included in scope for RHEL-5.11.0 which is the last RHEL5 minor release. This Bugzilla will soon be CLOSED as WONTFIX (at the end of RHEL5.11 development phase (Apr 22, 2014)). Please contact your account manager or support representative in case you need to escalate this bug.

Comment 5 RHEL Program Management 2014-06-03 12:27:07 UTC

Thank you for submitting this request for inclusion in Red Hat Enterprise Linux 5. We've carefully evaluated the request, but are unable to include it in RHEL5 stream. If the issue is critical for your business, please provide additional business justification through the appropriate support channels (https://access.redhat.com/site/support).

Comment 6 rahul 2014-06-23 11:17:23 UTC

(In reply to Andy Grover from comment #3)
> -> kernel, local disk only

The issue is seen with RHEL 6 versions also.
The issue is seen with local disks too.

If the issue cant be fixed then please let me know the explanation so that I can it will help in improving my knowledge and so that I can convey appropriate message to my team.