Bug 2162608

Summary:	64k arm kernel failed to print module_summary and module_top info with rd.memdebug=5
Product:	Red Hat Enterprise Linux 9	Reporter:	Coiby <coxu>
Component:	memstrack	Assignee:	ltao
Status:	CLOSED WONTFIX	QA Contact:	Li Wang <liwan>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	9.2	CC:	jieli, ltao, ruyang, xiawu
Target Milestone:	rc	Keywords:	Triaged
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
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Fixed In Version:		Doc Type:	If docs needed, set a value
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Last Closed:	2023-07-12 07:47:16 UTC	Type:	Bug
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
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Bug Depends On:
Bug Blocks:	2151999

Description Coiby 2023-01-20 07:11:26 UTC

Description of problem:

64k arm kernel failed to output module_summary and module_top info on hpe-apache-cn99xx-10.khw4.lab.eng.bos.redhat.com with rd.memdebug=5 when dong nfs dump.

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

RHEL-9.2.0-20230115.7

How reproducible:

always

Steps to Reproduce:
1. Install&boot 64k kernel 5.14.0-228.dd64kv4.el9.aarch64+64k and install memstrack
2. Set up nfs dumping
3. Append rd.memdebug=5 to KDUMP_COMMANDLINE_APPEND in /etc/sysconfig/kdump 
4. kdumpctl restart
5. Trigger kernel crash

Actual results:

No module_summary and module_top info is printed.

Expected results:

module_summary and module_top should be printed.

Additional info:

1. If I make kdump.sh wait 20s after finishing local dumping, module_summary and module_top info can be printed successfully.
2. This issue is not found on 4k arm kernel for nfs dumping. But it can also reproduced for local dumping.

Comment 2 Coiby 2023-01-30 02:45:19 UTC

I notice this issue can also reproduced for 4k kernel with local dumping. So actually there are two issues,
1) memstrack-report.sh which reports module_summary and module_top info is installed as a dracut cleanup hook but it doesn't have a chance to be executed when vmcore dumping is finished early 
2) vmcore dumping is done slower for 64k arm kernel compared with 4k arm kernel

Comment 6 ltao 2023-06-26 09:42:49 UTC

reset the DTM to 19