From e345ed18e229695fb75800508787945eaeca16ca Mon Sep 17 00:00:00 2001
From: Lianbo Jiang <lijiang@redhat.com>
Date: Thu, 12 Nov 2020 23:55:40 +0800
Subject: [PATCH] Add the rd.kdumploglvl option to control log level in the
 second kernel

Let's add the rd.kdumploglvl option to control log level in the second
kernel, which can make us avoid rebuilding the kdump initramfs after we
change the log level in /etc/sysconfig/kdump.

Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
Acked-by: Kairui Song <kasong@redhat.com>
---
 dracut-module-setup.sh |  1 -
 kdump-lib-initramfs.sh |  1 -
 kdump-logger.sh        | 48 +++++++++++++++++++++++++++++++++++++-----
 3 files changed, 43 insertions(+), 7 deletions(-)

diff --git a/dracut-module-setup.sh b/dracut-module-setup.sh
index 850c6f6..1750c6c 100755
--- a/dracut-module-setup.sh
+++ b/dracut-module-setup.sh
@@ -834,7 +834,6 @@ install() {
         kdump_install_random_seed
     fi
     dracut_install -o /etc/adjtime /etc/localtime
-    inst_simple "/etc/sysconfig/kdump"
     inst "$moddir/monitor_dd_progress" "/kdumpscripts/monitor_dd_progress"
     chmod +x ${initdir}/kdumpscripts/monitor_dd_progress
     inst "/bin/dd" "/bin/dd"
diff --git a/kdump-lib-initramfs.sh b/kdump-lib-initramfs.sh
index 14aac7b..d8d4893 100755
--- a/kdump-lib-initramfs.sh
+++ b/kdump-lib-initramfs.sh
@@ -1,6 +1,5 @@
 # These variables and functions are useful in 2nd kernel
 
-. /etc/sysconfig/kdump
 . /lib/kdump-lib.sh
 
 KDUMP_PATH="/var/crash"
diff --git a/kdump-logger.sh b/kdump-logger.sh
index c81e614..6d214af 100755
--- a/kdump-logger.sh
+++ b/kdump-logger.sh
@@ -20,15 +20,43 @@
 #   - @var kdump_sysloglvl - logging level to syslog (by logger command)
 #   - @var kdump_kmsgloglvl - logging level to /dev/kmsg (only for boot-time)
 #
-# If any of the variables is not set, this function set it to default:
-#   - @var kdump_stdloglvl = 3 (info)
-#   - @var kdump_sysloglvl = 3 (info)
-#   - @var kdump_kmsgloglvl = 0 (no logging)
+# If any of the variables is not set, the function dlog_init() sets it to default:
+#   - In the first kernel:
+#     - @var kdump_stdloglvl = 3 (info)
+#     - @var kdump_sysloglvl = 0 (no logging)
+#     - @var kdump_kmsgloglvl = 0 (no logging)
+#
+#   -In the second kernel:
+#    - @var kdump_stdloglvl = 0 (no logging)
+#    - @var kdump_sysloglvl = 3 (info)
+#    - @var kdump_kmsgloglvl = 0 (no logging)
 #
 # First of all you have to start with dlog_init() function which initializes
 # required variables. Don't call any other logging function before that one!
 #
 
+# The dracut-lib.sh is only available in the second kernel, and it won't
+# be used in the first kernel because the dracut-lib.sh is invisible in
+# the first kernel.
+if [ -f /lib/dracut-lib.sh ]; then
+    . /lib/dracut-lib.sh
+fi
+
+# @brief Get the log level from kernel command line.
+# @retval 1 if something has gone wrong
+# @retval 0 on success.
+#
+get_kdump_loglvl()
+{
+    (type -p getarg) && kdump_sysloglvl=$(getarg rd.kdumploglvl)
+    [ -z "$kdump_sysloglvl" ] && return 1;
+
+    (type -p isdigit) && isdigit $kdump_sysloglvl
+    [ $? -ne 0 ] && return 1;
+
+    return 0
+}
+
 # @brief Check the log level.
 # @retval 1 if something has gone wrong
 # @retval 0 on success.
@@ -52,8 +80,18 @@ check_loglvl()
 dlog_init() {
     local ret=0; local errmsg
 
+    if [ -s /proc/vmcore ];then
+        get_kdump_loglvl
+        if [ $? -ne 0 ];then
+            logger -t "kdump[$$]" -p warn -- "Kdump is using the default log level(3)."
+            kdump_sysloglvl=3
+        fi
+        kdump_stdloglvl=0
+        kdump_kmsgloglvl=0
+    fi
+
     [ -z "$kdump_stdloglvl" ] && kdump_stdloglvl=3
-    [ -z "$kdump_sysloglvl" ] && kdump_sysloglvl=3
+    [ -z "$kdump_sysloglvl" ] && kdump_sysloglvl=0
     [ -z "$kdump_kmsgloglvl" ] && kdump_kmsgloglvl=0
 
     for loglvl in "$kdump_stdloglvl" "$kdump_kmsgloglvl" "$kdump_sysloglvl"; do