Bug 1626477

Summary:	Bricks created with md devices up on NVMe drives doesn't work
Product:	[Red Hat Storage] Red Hat Gluster Storage	Reporter:	SATHEESARAN <sasundar>
Component:	rhhi	Assignee:	Sahina Bose <sabose>
Status:	CLOSED CURRENTRELEASE	QA Contact:	SATHEESARAN <sasundar>
Severity:	high	Docs Contact:
Priority:	high
Version:	rhhiv-1.5	CC:	godas, heinzm, rhs-bugs, sankarshan
Target Milestone:	---	Keywords:	Tracking, ZStream
Target Release:	RHHI-V 1.5.z Async
Hardware:	x86_64
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2019-05-20 04:55:45 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:
Bug Depends On:	1557434, 1626479
Bug Blocks:	1660740

Description SATHEESARAN 2018-09-07 12:31:48 UTC

Description of problem:
-----------------------
During the testing for RHHI4V-Ready, Marko has hit the problem with NVMe drives. Bricks created with md devices on top of NVMe drives, hit the "bio too big" problem

Version-Release number of selected component (if applicable):
-------------------------------------------------------------
RHHI 2.0
kernel-3.10.0-863.el7

How reproducible:
-----------------
Always

Steps to Reproduce:
-------------------
1. Create software RAID with 'md' over NVMe drives
2. Use this brick for engine volume

Actual results:
----------------
Error while creating bricks with md layer on top of NVMe drives

Expected results:
-----------------
No errors


Additional info:
------------------
Thanks Marko for the information

<snip>
[48684.118540] bio too big device dm-14 (504 > 256)
[48684.178821] md/raid0:md127: make_request bug: can't convert block across chunks or bigger than 512k 51000 128
[48684.183512] md/raid0:md127: make_request bug: can't convert block across chunks or bigger than 512k 51000 128
[48684.188373] md/raid0:md127: make_request bug: can't convert block across chunks or bigger than 512k 51000 128
[49010.568086] bio too big device dm-14 (512 > 256)
[49010.568124] Buffer I/O error on dev dm-18, logical block 40959815, lost async page write
[49010.568168] Buffer I/O error on dev dm-18, logical block 40959816, lost async page write
[49010.568192] Buffer I/O error on dev dm-18, logical block 40959817, lost async page write
[49010.568217] Buffer I/O error on dev dm-18, logical block 40959818, lost async page write
[49010.568247] Buffer I/O error on dev dm-18, logical block 40959819, lost async page write
[49010.568270] Buffer I/O error on dev dm-18, logical block 40959820, lost async page write
[49010.568294] Buffer I/O error on dev dm-18, logical block 40959821, lost async page write
[49010.568317] Buffer I/O error on dev dm-18, logical block 40959822, lost async page write
[49010.568341] Buffer I/O error on dev dm-18, logical block 40959823, lost async page write
[49010.568365] Buffer I/O error on dev dm-18, logical block 40959824, lost async page write
[49388.815989] ovirtmgmt: port 2(vnet0) entered disabled state
[49388.818310] device vnet0 left promiscuous mode
[49388.818321] ovirtmgmt: port 2(vnet0) entered disabled state
[49510.213142] ovirtmgmt: port 2(vnet0) entered blocking state
[49510.213146] ovirtmgmt: port 2(vnet0) entered disabled state
[49510.213238] device vnet0 entered promiscuous mode
[49510.213813] ovirtmgmt: port 2(vnet0) entered blocking state
[49510.213817] ovirtmgmt: port 2(vnet0) entered forwarding state
[49697.210495] bio too big device dm-14 (504 > 256)
[49697.258032] md/raid0:md127: make_request bug: can't convert block across chunks or bigger than 512k 61240 128
[49697.263049] md/raid0:md127: make_request bug: can't convert block across chunks or bigger than 512k 61240 128
[49697.267329] md/raid0:md127: make_request bug: can't convert block across chunks or bigger than 512k 61240 128
</snip>

Comment 1 Heinz Mauelshagen 2018-09-10 12:47:58 UTC

(In reply to SATHEESARAN from comment #0)
> Description of problem:
> -----------------------
> During the testing for RHHI4V-Ready, Marko has hit the problem with NVMe
> drives. Bricks created with md devices on top of NVMe drives, hit the "bio
> too big" problem
> 

If an option, you may work around this md/raid0 bug by deploying LVM striped LV(s) across the NVMe backing devices instead.

Comment 2 Sahina Bose 2018-11-19 05:22:39 UTC

Moving to ON_QA as the dependent fix is available in RHEL 7.6

Comment 5 SATHEESARAN 2019-02-05 16:50:57 UTC

Tested with RHV 4.2.8 async.

1. Created a md RAID0
2. Use this software RAID volume for lvmcache.

No problems observed and all looks good.