[PATCH v2] rpm-pkg: simplify installkernel %post

[Jose Ignacio Tornos Martinez <jtornosm@redhat.com>]

A new installkernel application is now included in systemd-udev package
and it has been improved to allow simplifications.

For the new installkernel application, as Davide says:
<<The %post currently does a shuffling dance before calling installkernel.
This isn't actually necessary afaict, and the current implementation
ends up triggering downstream issues such as
https://github.com/systemd/systemd/issues/29568
This commit simplifies the logic to remove the shuffling. For reference,
the original logic was added in commit 3c9c7a14b627("rpm-pkg: add %post
section to create initramfs and grub hooks").>>

But we need to keep the old behavior as well, because the old installkernel
application from grubby package, does not allow this simplification and
we need to be backward compatible to avoid issues with the different
packages. So the easiest solution is to check the package that provides
the installkernel application, and simplify (and fix for this
application at the same time), only if the package is systemd-udev.

cc: stable@vger.kernel.org
Co-Developed-by: Davide Cavalca <dcavalca@meta.com>
Signed-off-by: Jose Ignacio Tornos Martinez <jtornosm@redhat.com>
---
V1 -> V2:
- Complete to be backward compatible with the previous installkernel
application.

 scripts/package/kernel.spec | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/scripts/package/kernel.spec b/scripts/package/kernel.spec
index 3eee0143e0c5..d4276ddb6645 100644
--- a/scripts/package/kernel.spec
+++ b/scripts/package/kernel.spec
@@ -77,12 +77,16 @@ rm -rf %{buildroot}
 
 %post
 if [ -x /sbin/installkernel -a -r /boot/vmlinuz-%{KERNELRELEASE} -a -r /boot/System.map-%{KERNELRELEASE} ]; then
+if [ $(rpm -qf /sbin/installkernel --queryformat "%{n}") = systemd-udev ];then
+/sbin/installkernel %{KERNELRELEASE} /boot/vmlinuz-%{KERNELRELEASE} /boot/System.map-%{KERNELRELEASE}
+else
 cp /boot/vmlinuz-%{KERNELRELEASE} /boot/.vmlinuz-%{KERNELRELEASE}-rpm
 cp /boot/System.map-%{KERNELRELEASE} /boot/.System.map-%{KERNELRELEASE}-rpm
 rm -f /boot/vmlinuz-%{KERNELRELEASE} /boot/System.map-%{KERNELRELEASE}
 /sbin/installkernel %{KERNELRELEASE} /boot/.vmlinuz-%{KERNELRELEASE}-rpm /boot/.System.map-%{KERNELRELEASE}-rpm
 rm -f /boot/.vmlinuz-%{KERNELRELEASE}-rpm /boot/.System.map-%{KERNELRELEASE}-rpm
 fi
+fi
 
 %preun
 if [ -x /sbin/new-kernel-pkg ]; then
-- 
2.43.0