Kdump for ARM (vmcore generation problem)

I'm trying to make Kdump work for ARM. Till now i've managed to get the /dev/oldmem interface working for taking dumps. Now i want to get the /proc/vmcore interface working.
I'm unclear how to generate the elfcore headers required by routines in vmcore.c.

Hi,
I'm trying to make Kdump work for ARM. Till now i've managed to get the /dev/oldmem interface working for taking dumps. Now i want to get the /proc/vmcore interface working.
I'm unclear how to generate the elfcore headers required by routines in vmcore.c.

Quoted 7 lines · Indraneel

Hi,
I'm trying to make Kdump work for ARM. Till now i've managed to get the /dev/oldmem interface working for taking dumps. Now i want to get the /proc/vmcore interface working.
I'm unclear how to generate the elfcore headers required by routines in vmcore.c.

Hi Indraneel,

kexec-tools in user space generates those headers. Have a loot at kexec-tools code.

Thanks
Vivek

Hi Vivek/Bernhard,

Quoted 9 lines · Vivek Goyal

Quoted 7 lines · Indraneel

Hi,
I'm trying to make Kdump work for ARM. Till now i've managed to get the /dev/oldmem interface working for taking dumps. Now i want to get the /proc/vmcore interface working.
I'm unclear how to generate the elfcore headers required by routines in vmcore.c.

Quoted 4 lines

Hi Indraneel,

kexec-tools in user space generates those headers. Have a loot at kexec-tools code.

Thanks for the lead. I'm looking into kexec-tools and trying to do changes for ARM. I'm unable to interpret one of the comments in kexec/crashdump-elf.c which says,
" The separate PT_LOAD program header is required either because the
kernel is mapped at a different location than the rest of the physical memory or because we need to support relocatable kernels. Or both as on x86_64. "

Can you please provide some more clarification for this so that i can figure out whether a separate PT_LOAD header is required for ARM architecture as well (esp. the "kernel mapped to diff. loc. part of the comment").