From 41f1d5b2e98b5ecdc1412094d534928ef277b516 Mon Sep 17 00:00:00 2001
From: Tao Liu <ltao@redhat.com>
Date: May 14 2021 06:27:03 +0000
Subject: fadump: fix dump capture failure to root disk


Resolves: bz1952652
Upstream: fedora
Conflict: none

commit d0e9c51e0de57273a99af8484515f213b8414e65
Author: Hari Bathini <hbathini@linux.ibm.com>
Date:   Thu Apr 22 18:21:59 2021 +0530

    fadump: fix dump capture failure to root disk

    If the dump target is the root disk, kdump scripts add an entry in
    /etc/fstab for root disk with /sysroot as the mount point. The root
    disk, passed through root=<> kernel commandline parameter, is mounted
    at /sysroot in read-only mode before switching from initial ramdisk.
    So, in fadump mode, a remount of /sysroot to read-write mode is needed
    to capture dump successfully, because /sysroot is already mounted as
    read-only based on root=<> boot parameter.

    Commit e8ef4db8ff91 ("Fix dump_fs mount point detection and fallback
    mount") removed initialization of $_op variable, the variable holding
    the options the dump target was mounted with, leading to the below
    error as remount was skipped:

      kdump[586]: saving to /sysroot/var/crash/127.0.0.1-2021-04-22-07:22:08/
      kdump.sh[587]: mkdir: cannot create directory '/sysroot/var/crash/127.0.0.1-2021-04-22-07:22:08/': Read-only file system
      kdump[589]: saving vmcore failed

    Restore $_op variable initialization in dump_fs() function to fix this.

    Fixes: e8ef4db8ff91 ("Fix dump_fs mount point detection and fallback mount")
    Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
    Acked-by: Kairui Song <kasong@redhat.com>

Signed-off-by: Tao Liu <ltao@redhat.com>

---

diff --git a/kdump-lib-initramfs.sh b/kdump-lib-initramfs.sh
index 341aa00..d0d124f 100755
--- a/kdump-lib-initramfs.sh
+++ b/kdump-lib-initramfs.sh
@@ -119,7 +119,8 @@ dump_fs()
 {
     local _exitcode
     local _mp=$1
-    ddebug "dump_fs _mp=$_mp"
+    local _op=$(get_mount_info OPTIONS target $_mp -f)
+    ddebug "dump_fs _mp=$_mp _opts=$_op"
 
     if ! is_mounted "$_mp"; then
         dinfo "dump path \"$_mp\" is not mounted, trying to mount..."
@@ -139,8 +140,8 @@ dump_fs()
 
     # Only remount to read-write mode if the dump target is mounted read-only.
     if [[ "$_op" = "ro"* ]]; then
-       dinfo "Mounting Dump target $_dev in rw mode."
-       mount -o remount,rw $_dev $_mp || return 1
+       dinfo "Remounting the dump target in rw mode."
+       mount -o remount,rw $_mp || return 1
     fi
 
     mkdir -p $_dump_path || return 1