[PATCH v2] earlykdump: generate symlink with stable name to kernel image and iniramfs

[Kairui Song]

There is currently a problem with earlykdump image building, when a user
is upgrading kernel, dracut will generate new initramfs for the new
kernel, and earlykdump will install currently running version of kernel
into the initramfs, and remain the version based kernel image naming
untouched. But after a reboot the new kernel is running, and it
will try to load the image corresponding to the new kernel version by
file naming.

This patch fixes the problem by creating a symlink with unified stable
naming to the installed kernel image and initramfs, and use the symlink
instand so it will always work despite the kernel version number change.

Signed-off-by: Kairui Song <kasong(a)redhat.com&gt;
---
Update from V1:

 - Use a symlink as stable reference of installed kernel and initramfs
   and keep the installation naming same untouched, so user could know
   the installed kernel version easily.

 dracut-early-kdump-module-setup.sh |  5 +++++
 dracut-early-kdump.sh              | 13 ++-----------
 2 files changed, 7 insertions(+), 11 deletions(-)

diff --git a/dracut-early-kdump-module-setup.sh b/dracut-early-kdump-module-setup.sh
index 7613fbc..bd83ad6 100755
--- a/dracut-early-kdump-module-setup.sh
+++ b/dracut-early-kdump-module-setup.sh
@@ -22,11 +22,13 @@ depends() {
 
 prepare_kernel_initrd() {
     KDUMP_BOOTDIR=$(check_boot_dir "${KDUMP_BOOTDIR}")
+
     if [ -z "$KDUMP_KERNELVER" ]; then
         kdump_kver=`uname -r`
     else
         kdump_kver=$KDUMP_KERNELVER
     fi
+
     KDUMP_KERNEL="${KDUMP_BOOTDIR}/${KDUMP_IMG}-${kdump_kver}${KDUMP_IMG_EXT}"
     KDUMP_INITRD="${KDUMP_BOOTDIR}/initramfs-${kdump_kver}kdump.img"
 }
@@ -41,4 +43,7 @@ install() {
     prepare_kernel_initrd
     inst_binary "$KDUMP_KERNEL"
     inst_binary "$KDUMP_INITRD"
+
+    ln_r "$KDUMP_KERNEL"
"${KDUMP_BOOTDIR}/${KDUMP_IMG}-earlykdump${KDUMP_IMG_EXT}"
+    ln_r "$KDUMP_INITRD" "${KDUMP_BOOTDIR}/initramfs-earlykdump.img"
 }
diff --git a/dracut-early-kdump.sh b/dracut-early-kdump.sh
index 34a9909..69a34eb 100755
--- a/dracut-early-kdump.sh
+++ b/dracut-early-kdump.sh
@@ -18,17 +18,8 @@ prepare_parameters()
     EARLY_KDUMP_CMDLINE=$(prepare_cmdline "${KDUMP_COMMANDLINE}"
"${KDUMP_COMMANDLINE_REMOVE}" "${KDUMP_COMMANDLINE_APPEND}")
     KDUMP_BOOTDIR=$(check_boot_dir "${KDUMP_BOOTDIR}")
 
-    #make early-kdump kernel string
-    if [ -z "$KDUMP_KERNELVER" ]; then
-        EARLY_KDUMP_KERNELVER=`uname -r`
-    else
-        EARLY_KDUMP_KERNELVER=$KDUMP_KERNELVER
-    fi
-
-   
EARLY_KDUMP_KERNEL="${KDUMP_BOOTDIR}/${KDUMP_IMG}-${EARLY_KDUMP_KERNELVER}${KDUMP_IMG_EXT}"
-
-    #make early-kdump initrd string
-   
EARLY_KDUMP_INITRD="${KDUMP_BOOTDIR}/initramfs-${EARLY_KDUMP_KERNELVER}kdump.img"
+   
EARLY_KDUMP_KERNEL="${KDUMP_BOOTDIR}/${KDUMP_IMG}-earlykdump${KDUMP_IMG_EXT}"
+    EARLY_KDUMP_INITRD="${KDUMP_BOOTDIR}/initramfs-earlykdump.img"
 }
 
 early_kdump_load()
-- 
2.20.1