I followed the instructions here:
https://fedoraproject.org/wiki/How_to_use_kdump_to_debug_kernel_crashes
After booting with crashkernel=128M, starting the kdump service
which is running:
# kdumpctl status
Kdump is operational
I enabled sysrq:
echo 1 > /proc/sys/kernel/sysrq
Then at the console I hit:
AltGr + PrtSc + c
and the kernel does crash with a NULL pointer dereference as expected,
but kdump never runs. The only thing I could do is hard-reboot.
Nothing is written in /var/crash.
(I also disabled SELinux for good measure, just in case that could be
it, but it makes no difference.)
Rich.
kernel 4.8.10-300.fc25.x86_64
kexec-tools-2.0.13-7.fc25.1.x86_64
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Richard Jones, Virtualization Group, Red Hat
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