Add Kdump option to disable reboot after save_core

By default, Kdump reboots the system after the crash dump is saved.
While this works in most cases, it does not work for systems hosted in
RAM where the crash dump is lost once rebooted. To support this
scenario, a new option in the kdump.conf, disable_crash_dump_reboot, is
added and set to 0 by default. Setting this option to 1 will disable the
reboot by having the kdumpctl script exit instead.

Author: nangelastro

SPECS/kexec-tools/kdump.conf

@@ -162,6 +162,12 @@
 #             to send fence_kdump notifications to.
 #             (this option is mandatory to enable fence_kdump).
 #
+# disable_crash_dump_reboot <0 | 1>
+#           - Disables the default action to reboot after the crash dump is
+#             saved. This is particularly useful when the operating system is
+#             running in RAM and reboots would otherwise remove the crash dump.
+#             Specify 1 to disable rebooting once the crash dump is saved.
+#
 
 #raw /dev/vg/lv_kdump
 #ext4 /dev/vg/lv_kdump
@@ -183,3 +189,4 @@ core_collector makedumpfile -l --message-level 1 -d 31
 #dracut_args --omit-drivers "cfg80211 snd" --add-drivers "ext2 ext3"
 #fence_kdump_args -p 7410 -f auto -c 0 -i 10
 #fence_kdump_nodes node1 node2
+#disable_crash_dump_reboot 0

SPECS/kexec-tools/kdumpctl

@@ -243,7 +243,7 @@ check_config()
 		case "$config_opt" in
 		\#* | "")
 			;;
-		raw|ext2|ext3|ext4|minix|btrfs|xfs|nfs|ssh|sshkey|path|core_collector|kdump_post|kdump_pre|extra_bins|extra_modules|failure_action|default|final_action|force_rebuild|force_no_rebuild|dracut_args|fence_kdump_args|fence_kdump_nodes)
+		raw|ext2|ext3|ext4|minix|btrfs|xfs|nfs|ssh|sshkey|path|core_collector|kdump_post|kdump_pre|extra_bins|extra_modules|failure_action|default|final_action|force_rebuild|force_no_rebuild|dracut_args|fence_kdump_args|fence_kdump_nodes|disable_crash_dump_reboot)
 			# remove inline comments after the end of a directive.
 			[ -z "$config_val" ] && {
 				echo "Invalid kdump config value for option $config_opt."
@@ -1249,6 +1249,23 @@ main ()
 	  start)
 		if [ -s /proc/vmcore ]; then
 			save_core
+
+			local _disable_crash_dump_reboot disable_crash_dump_reboot="0"
+			_disable_crash_dump_reboot=`grep ^disable_crash_dump_reboot $KDUMP_CONFIG_FILE 2>/dev/null`
+
+			if [ $? -eq 0 ]; then
+				disable_crash_dump_reboot=`echo $_disable_crash_dump_reboot | cut -d' '  -f2`
+
+				if [ "$disable_crash_dump_reboot" != "0" ] && [ "$disable_crash_dump_reboot" != "1" ]; then
+					echo "Error: disable_crash_dump_reboot value is invalid"
+					return 1
+				fi
+			fi
+
+			if [ "$disable_crash_dump_reboot" == "1" ]; then
+				exit 0
+			fi
+
 			reboot
 		else
 			start

SPECS/kexec-tools/kexec-tools.signatures.json

@@ -20,14 +20,14 @@
   "kdump-lib-initramfs.sh": "ff4b63f99470ee796fd7e4a532dde241c4da02909306926a08a172457775a92a",
   "kdump-lib.sh": "3d50507626d4a92b8448c7d6604923f6f460c4cb5c8b18977381a7d5e516dfba",
   "kdump-udev-throttler": "125d538a59172f779b40ea32fea1e4eb50d849f25eb2537a48328d4401136679",
-  "kdump.conf": "c4cd6c4a2f00e7df10d939bc2f35f8b6b8a3edd71245aa3ba0d7fff53d9f42e8",
+  "kdump.conf": "c1b69d46daa5adc296d3042403c084d780389b18abf00849d6743130220d155f",
   "kdump.conf.5": "bab6c7b171f76e8c6df91bb7db852815caacbc3cd3d4309a1dc58d36950440e4",
   "kdump.service": "ed8d22fafa6cfafaddcfd9fec82e3fa7fa42aa0366f69676fafa97e200b0506a",
   "kdump.sysconfig": "d03a24659c08aa4ce5a8e54edbe64e149f8c572c76c4e338d84dbdfbeab8fb63",
   "kdump.sysconfig.aarch64": "a829f3a0f88d983ccec2782b048f12a2eafca71aac4dd42acac2eaea8f7dd8d9",
   "kdump.sysconfig.i386": "1175bcc11be49841d4b8c3f9612e68bb7b2e0e8f00067ffa782fd9dba04f821d",
   "kdump.sysconfig.x86_64": "850b3be780165d0721edb8d34b2ba28aafc60b29850ff627daf04190369e359c",
-  "kdumpctl": "34976fa2ca34a455f393d2ac212a628d73ba4113b44f0e819c3cb5b1195e504b",
+  "kdumpctl": "2d6d70544525cdbdea999307b7a2631c6f9cda51a02225dfb4159bc6a45ce465",
   "kdumpctl.8": "025a39d212eed0584da7c23c1bb50d6ab797a0fa3c686ac6b80391af875dbaec",
   "kexec-kdump-howto.txt": "e783390a9aa582a2b5e7981cd3277081385340b5873a3f0633c789811876eccb",
   "kexec-tools-2.0.27.tar.xz": "38d78bcfa33a88928324b57dc81f50c1dfc279eede45e80957ca18f4e84b8187",

SPECS/kexec-tools/kexec-tools.spec

@@ -6,7 +6,7 @@
 Summary:        The kexec/kdump userspace component
 Name:           kexec-tools
 Version:        2.0.27
-Release:        7%{?dist}
+Release:        8%{?dist}
 License:        GPLv2
 Vendor:         Microsoft Corporation
 Distribution:   Azure Linux
@@ -330,6 +330,9 @@ done
 /usr/share/makedumpfile/
 
 %changelog
+* Mon Sep 30 2024 Nicholas Angelastro <nangelastro@microsoft.com> - 2.0.27-8
+- Add kdump option to disable rebooting after saving crash dump
+
 * Tue Jul 09 2024 Chris Co <chrco@microsoft.com> - 2.0.27-7
 - Remove requires on dhcp-client