Bug 215417

Summary: kdump kernel panics early in boot
Product: Red Hat Enterprise Linux 5 Reporter: Amul Shah <amul.shah>
Component: kernelAssignee: Red Hat Kernel Manager <kernel-mgr>
Status: CLOSED CURRENTRELEASE QA Contact: Red Hat Kernel QE team <kernel-qe>
Severity: high Docs Contact:
Priority: medium    
Version: 5.0CC: anderson, benjamin.romer, bruce.vessey, prasanna.nagasamudram, qcai
Target Milestone: ---   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: beta2 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2006-12-23 02:37:07 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Attachments:
Description Flags
This patch will avoid any attempts to reserve memory about end_pfn_map, the end of memory none

Description Amul Shah 2006-11-13 21:14:50 UTC
Description of problem:
The kdump crash kernel panics when it tries to reserve the MP Config
tables on an ES7000.

The MP Config table is located above 1MB of physical memory in a
reserved memory area.  It is located outside the first 1MB area because
the tables are too large, 240k.

The crash kernel is given a user defined memory map with E820 reserved
and ACPI areas passed in by kexec tools and a usable area from 16MB
physical to 80MB physical.  This user defined map causes the top of
memory to be set as 80MB.

The ACPI tables and MP Tables reside higher in memory.  When reserving
memory with reserve_bootmem_generic, the function has a BUG panic if the
memory location to reserve is above the top of usable memory for the node.  The
MP table is above the top of memory in a user defined memory map.

Version-Release number of selected component (if applicable):
Tested with RHEL5 Beta 2 Milestone 9


How reproducible:
Always on an ES7000

Steps to Reproduce:
1. Setup for kdump with boot paramter crashkernel=64M@16M
2. Install the kernel with  kexec -p /boot/vmlinux-kdump --args-linux
--command-line="`cat /proc/cmdline` lpj=1306000
earlyprintk=serial,ttyS0,115200n8" --initrd=/boot/initrd-kdump
3. Issue alt-sysrq-c (or echo c > /proc/sysrq-trigger)
  
Actual results:
Actual kernel panic to follow

Expected results:
Kdump kernel should boot up.

Additional info:
http://www.ussg.iu.edu/hypermail/linux/kernel/0611.0/0796.html
The associated patch is currently in 2.6.19-rc5-mm1

Comment 1 Amul Shah 2006-11-13 21:14:50 UTC
Created attachment 141102 [details]
This patch will avoid any attempts to reserve memory about end_pfn_map, the end of memory

Comment 2 RHEL Program Management 2006-11-14 17:41:20 UTC
This request was evaluated by Red Hat Product Management for inclusion in a Red
Hat Enterprise Linux major release.  Product Management has requested further
review of this request by Red Hat Engineering, for potential inclusion in a Red
Hat Enterprise Linux Major release.  This request is not yet committed for
inclusion.

Comment 3 Amul Shah 2006-11-28 18:14:28 UTC
FYI, this patch has been accepted into 2.6.19-rc6

Comment 4 Don Zickus 2006-12-04 18:35:56 UTC
in 2.6.18-1.2789.el5

Comment 5 Daniel W. Ottey 2006-12-05 13:53:37 UTC
Is this kernel available for download & testing, or do we need to wait for the
next release?

Comment 6 RHEL Program Management 2006-12-23 02:37:07 UTC
A package has been built which should help the problem described in 
this bug report. This report is therefore being closed with a resolution 
of CURRENTRELEASE. You may reopen this bug report if the solution does 
not work for you.