From 7b7ddaba88af9bcbbcc3d219e1c7f00b3a61152d Mon Sep 17 00:00:00 2001
From: Kairui Song <kasong@redhat.com>
Date: Fri, 2 Jul 2021 01:31:26 +0800
Subject: [PATCH] kdump-lib.sh: kdump_get_arch_recommend_size uses
 crashkernel.default

The new `crashkernel.default` file in kernel package can be used as the
ck_cmdline source.

Also keep the legacy code so old kernel packages will still work.

Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Pingfan Liu <piliu@redhat.com>
---
 kdump-lib.sh | 37 +++++++++++++++++++++++--------------
 1 file changed, 23 insertions(+), 14 deletions(-)

diff --git a/kdump-lib.sh b/kdump-lib.sh
index df0aa02..4bd9751 100755
--- a/kdump-lib.sh
+++ b/kdump-lib.sh
@@ -952,31 +952,40 @@ get_recommend_size()
 }
 
 # return recommended size based on current system RAM size
+# $1: kernel version, if not set, will defaults to `uname -r`
 kdump_get_arch_recommend_size()
 {
-    if ! [[ -r "/proc/iomem" ]] ; then
+    local kernel=$1 arch
+
+    if ! [ -r "/proc/iomem" ] ; then
         echo "Error, can not access /proc/iomem."
         return 1
     fi
-    arch=$(lscpu | grep Architecture | awk -F ":" '{ print $2 }' | tr [:lower:] [:upper:])
 
-    if [ $arch == "X86_64" ] || [ $arch == "S390X" ]; then
-        ck_cmdline="1G-4G:160M,4G-64G:192M,64G-1T:256M,1T-:512M"
-    elif [ $arch == "AARCH64" ]; then
-        ck_cmdline="2G-:448M"
-    elif [ $arch == "PPC64LE" ]; then
-        if is_fadump_capable; then
-            ck_cmdline="4G-16G:768M,16G-64G:1G,64G-128G:2G,128G-1T:4G,1T-2T:6G,2T-4T:12G,4T-8T:20G,8T-16T:36G,16T-32T:64G,32T-64T:128G,64T-:180G"
-        else
-            ck_cmdline="2G-4G:384M,4G-16G:512M,16G-64G:1G,64G-128G:2G,128G-:4G"
+    [ -z "$kernel" ] && kernel=$(uname -r)
+    ck_cmdline=$(cat "/usr/lib/modules/$kernel/crashkernel.default" 2>/dev/null)
+
+    if [ -n "$ck_cmdline" ]; then
+        ck_cmdline=${ck_cmdline#crashkernel=}
+    else
+        arch=$(lscpu | grep Architecture | awk -F ":" '{ print $2 }' | tr '[:lower:]' '[:upper:]')
+        if [ "$arch" = "X86_64" ] || [ "$arch" = "S390X" ]; then
+            ck_cmdline="1G-4G:160M,4G-64G:192M,64G-1T:256M,1T-:512M"
+        elif [ "$arch" = "AARCH64" ]; then
+            ck_cmdline="2G-:448M"
+        elif [ "$arch" = "PPC64LE" ]; then
+            if is_fadump_capable; then
+                ck_cmdline="4G-16G:768M,16G-64G:1G,64G-128G:2G,128G-1T:4G,1T-2T:6G,2T-4T:12G,4T-8T:20G,8T-16T:36G,16T-32T:64G,32T-64T:128G,64T-:180G"
+            else
+                ck_cmdline="2G-4G:384M,4G-16G:512M,16G-64G:1G,64G-128G:2G,128G-:4G"
+            fi
         fi
     fi
 
     ck_cmdline=$(echo $ck_cmdline | sed -e 's/-:/-102400T:/g')
     sys_mem=$(get_system_size)
-    result=$(get_recommend_size $sys_mem "$ck_cmdline")
-    echo $result
-    return 0
+
+    get_recommend_size "$sys_mem" "$ck_cmdline"
 }
 
 # Print all underlying crypt devices of a block device