Re: crash and upstream arm kernel

[Dave Anderson]

----- Original Message -----
>  Hi, Dave
>  
>  I played with kdump on arm platform recently. It works well for me with a few
>  patches to kexec-tools, but seems crash tool can not recogonize the vmlinux.
>  
>  Do you have any hints about below error? I'm sure the vmlinux and vmcore are
>  same build with rh cross compiler 5.2.1:
>  
>  WARNING: kernels compiled by different gcc versions:
>    vmlinux: (unknown)
>    /var/crash/127.0.0.1-2015-11-28-16:00:50/vmcore kernel: 5.2.1
>                                                                                  
>  WARNING: kernel version inconsistency between vmlinux and dumpfile
>                                                                                  
>  crash: incompatible arguments:
>     vmlinux is not SMP -- /var/crash/127.0.0.1-2015-11-28-16:00:50/vmcore is SMP
>        
>  Thanks
>  Dave
>   
It's not finding the "gcc version" string (the first warning), the
linux_banner string 
in the vmcore is not matching the one in the vmlinux file (the second warning), and
finally
it's not finding the "SMP" part of the string (the fatal error).

What does this show:

 $ strings vmlinux | grep "Linux version"

Here's one from a natively-compiled ARM64:

# strings /usr/lib/debug/lib/modules/4.2.0-0.rc3.15.el7.aarch64/vmlinux | grep "Linux
version"
Linux version 4.2.0-0.rc3.15.el7.aarch64 (mockbuild(a)arm64-002.build.eng.bos.redhat.com)
(gcc version 4.8.3 20140911 (Red Hat 4.8.3-9) (GCC) ) #1 SMP Wed Jul 29 13:26:18 EDT 2015
#

Entering "crash -d1 ..." will show the details on what it found.

Dave