File kdump-fadump-avoid-multipath-optimizations.patch of Package kdump.21347

From: Hari Bathini <hbathini@linux.ibm.com>
Date: Mon, 20 Aug 2018 16:11:38 +0200
Subject: fadump: avoid multipath optimizations that break regular boot
References: bsc#1101730
Upstream: merged
Git-commit: dc29a820687a3a267c56ad1b125cb670dbd194ad

Since commit 9a3764178a91 ("Blacklist unneeded multipath devices")
multipath devices that are not needed while capturing dump were
blacklisted. This reduces the memory requirements on kdump kernel.
But when this optimization is added to default initrd by including
dump capturing support for FADump, it is observed to mess with the
initialization of such blacklisted multipath devices while booting
the production kernel. To avoid such issues, use this optimization
only while booting a capture kernel.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 init/CMakeLists.txt        |    1 +
 init/kdump-boot.sh         |   16 ++++++++++++++++
 init/module-setup.sh       |    1 +
 init/setup-kdump.functions |    2 +-
 4 files changed, 19 insertions(+), 1 deletion(-)
 create mode 100755 init/kdump-boot.sh

--- a/init/CMakeLists.txt
+++ b/init/CMakeLists.txt
@@ -98,6 +98,7 @@ INSTALL(
 INSTALL(
     FILES
         ${CMAKE_CURRENT_SOURCE_DIR}/kdump-root.sh
+        ${CMAKE_CURRENT_SOURCE_DIR}/kdump-boot.sh
         ${CMAKE_CURRENT_SOURCE_DIR}/module-setup.sh
         ${CMAKE_CURRENT_SOURCE_DIR}/mount-kdump.sh
     DESTINATION
--- /dev/null
+++ b/init/kdump-boot.sh
@@ -0,0 +1,16 @@
+#! /bin/sh
+# -*- mode: shell-script; indent-tabs-mode: nil; sh-basic-offset: 4; -*-
+# ex: ts=8 sw=4 sts=4 et filetype=sh
+
+# An Initrd with dump capturing support can boot a production kernel
+# as well (FADump). In such scenario, apply optimizations only while
+# booting the capture kernel - this is a kernel that
+#   a) has a /proc/vmcore file waiting to be saved.
+#   b) reboots after saving the dump.
+
+# apply multipath optimizations
+if [ -s /proc/vmcore ]; then
+    # Replace the multipath.conf file with the one optimized for kdump.
+    rm -f /etc/multipath.conf
+    mv /etc/multipath.conf.kdump /etc/multipath.conf
+fi
--- a/init/module-setup.sh
+++ b/init/module-setup.sh
@@ -264,6 +264,7 @@ install() {
     kdump_setup_files "$initdir" "$kdump_mpath_wwids"
 
     inst_hook cmdline 50 "$moddir/kdump-root.sh"
+    inst_hook cmdline 50 "$moddir/kdump-boot.sh"
     if dracut_module_included "systemd" ; then
 	inst_binary "$moddir/device-timeout-generator" \
 	    "$systemdutildir"/system-generators/kdump-device-timeout-generator
--- a/init/setup-kdump.functions
+++ b/init/setup-kdump.functions
@@ -1179,7 +1179,7 @@ function kdump_setup_files()						   # {
     #
     # create modified multipath.conf
     #
-    kdump_modify_multipath "$mpathdevs" > "${outdir}/etc/multipath.conf"
+    kdump_modify_multipath "$mpathdevs" > "${outdir}/etc/multipath.conf.kdump"
 
     #
     # filter out problematic sysctl settings