6.2.4 Kdump tools fail to create vmcore.dmesg.txt on X-Gene 3 and ThunderX2 platforms

The Kdump crash dump tools fail to create a vmcore-dmesg.txt file (which is created with the vmcore file) on the X-Gene 3 and ThunderX2 platforms. This failure to create the vmcore-dmesg.txt file might result in a segmentation fault similar to the following:

...
kdump: saving to /sysroot//var/crash/127.0.0.1-2018-05-22-12:34:45/
kdump: saving vmcore-dmesg.txt
/lib/kdump-lib-initramfs.sh: line 118:   459 Segmentation fault      
$_dmesg_collector /proc/vmcore > ${_path}/vmcore-dmesg-incomplete.txt
kdump: saving vmcore-dmesg.txt failed
kdump: saving vmcore
Copying data                                      : [100.0 %] \          
eta: 0s
kdump: saving vmcore complete 

You can retrieve the dmesg output manually by running crash against the vmcore and using the dmesg command when in the crash shell.

(Bug ID 29709556)