The 50-kdump-tools.rules file needs update for latest kernel 6.6 feature

[Eric DeVolder]

The following series has landed in mainline, and will be present in 6.6.

 "crash: Kernel handling of CPU and memory hot un/plug"
 https://<email address hidden>/

 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d68b4b6f307d155475cce541f2aee938032ed22e

To take advantage of the performance benefits of that series, 50-kdump-tools.rules
needs an update to optimize the handling of CPU and memory hotplug changes.

It is safe to deploy these rule updates now, ahead of distros/kernels
enabling the feature, since the crash_hotplug sysfs nodes would not be
present and thus the newly introduced rules in 50-kdump-tools would act as a
nop-op and fall thru for legacy behavior. But when distros/kernels
enable the feature, then 50-kdump-tools rules is ready and can properly take
advantage.

[Eric DeVolder (edevolde)]

The 50-kdump-tools.rules file should look like this:

# 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=="memory", ACTION=="online", PROGRAM="/usr/sbin/kdump-config try-reload"
SUBSYSTEM=="memory", ACTION=="offline", PROGRAM="/usr/sbin/kdump-config try-reload"
SUBSYSTEM=="cpu", ACTION=="add", PROGRAM="/usr/sbin/kdump-config try-reload"
SUBSYSTEM=="cpu", ACTION=="remove", PROGRAM="/usr/sbin/kdump-config try-reload"
SUBSYSTEM=="cpu", ACTION=="online", PROGRAM="/usr/sbin/kdump-config try-reload"

LABEL="kdump_reload_end"

where the first 3 lines and last 1 line are new/added.