reset kernel crashkernel for the special case where the kernel is updated right after kexec-tools
Resolves: bz1895258
Upstream: Fedora
Conflict: None
commit 5e8c751c39a5ec9d10009cba1c2bd554a5763b90
Author: Coiby Xu <coxu@redhat.com>
Date: Thu Dec 2 17:19:50 2021 +0800
reset kernel crashkernel for the special case where the kernel is updated right after kexec-tools
When kexec-tools updates the default crashkernel value, it will try to
reset the existing installed kernels including the currently running
kernel. So the running kernel could have different kernel cmdline
parameters from /proc/cmdline. When installing a kernel after updating
kexec-tools, /usr/lib/kernel/install.d/20-grub.install would be called
by kernel-install [1] which would use /proc/cmdline to set up new kernel's
cmdline. To address this special case, reset the new kernel's crashkernel
and fadump value to the value that would be used by running kernel after
rebooting by the installation hook. One side effect of this commit is it
would reset the installed kernel's crashkernel even currently running kernel
don't use the default crashkernel value after rebooting. But I think this
side effect is a benefit for the user.
The implementation depends on kernel-install which run the scripts in
/usr/lib/kernel/install.d passing the following arguments,
add KERNEL-VERSION $BOOT/MACHINE-ID/KERNEL-VERSION/ KERNEL-IMAGE [INITRD-FILE ...]
An concrete example is given as follows,
add 5.11.12-300.fc34.x86_64 /boot/e986846f63134c7295458cf36300ba5b/5.11.12-300.fc34.x86_64 /lib/modules/5.11.12-300.fc34.x86_64/vmlinuz
kernel-install could be started by the kernel package's RPM scriplet [2].
As mentioned in previous commit "try to reset kernel crashkernel when
kexec-tools updates the default crashkernel value", kdumpctl has difficulty
running in RPM scriptlet fore CoreOS. But rpm-ostree ignores all kernel hooks,
there is no need to disable the kernel hook for CoreOS/Atomic/Silverblue. But a
collaboration between rpm-ostree and kexec-tools is needed [3] to take care
of this special case.
Note the crashkernel.default support is dropped.
[1] https://www.freedesktop.org/software/systemd/man/kernel-install.html
[2] https://src.fedoraproject.org/rpms/kernel/blob/rawhide/f/kernel.spec#_2680
[3] https://github.com/coreos/rpm-ostree/issues/2894
Reviewed-by: Pingfan Liu <piliu@redhat.com>
Reviewed-by: Philipp Rudo <prudo@redhat.com>
Signed-off-by: Coiby Xu <coxu@redhat.com>
Signed-off-by: Coiby Xu <coxu@redhat.com>