98-kexec.rules

# The kernel updates the crash elfcorehdr for CPU and memory changes
SUBSYSTEM=="cpu", ATTRS{crash_hotplug}=="1", GOTO="kdump_reload_end"
SUBSYSTEM=="memory", ATTRS{crash_hotplug}=="1", GOTO="kdump_reload_end"

SUBSYSTEM=="cpu", ACTION=="add", GOTO="kdump_reload"
SUBSYSTEM=="cpu", ACTION=="remove", GOTO="kdump_reload"
SUBSYSTEM=="memory", ACTION=="online", GOTO="kdump_reload"
SUBSYSTEM=="memory", ACTION=="offline", GOTO="kdump_reload"

GOTO="kdump_reload_end"

LABEL="kdump_reload"

# If kdump is not loaded, calling kdump-udev-throttle will end up
# doing nothing, but systemd-run will always generate extra logs for
# each call, so trigger the kdump-udev-throttler only if kdump
# service is active to avoid unnecessary logs
RUN+="/bin/sh -c '/usr/bin/systemctl is-active kdump.service || exit 0; /usr/bin/systemd-run --quiet --no-block /usr/lib/udev/kdump-udev-throttler'"

LABEL="kdump_reload_end"