Sometimes, debugging the kdump service failure becomes very challenging because there is no complete debugging information, which requires modification of the options or the scripts like kdumpctl, mkdumprd, etc to collect the information for troubleshooting. That means users have to wait for the next failure so that they can capture the additional information, which could waste valuable time. This patch series will improve kdump debugging messages and have a chance to save them to journald or a file. It includes the following patches: [1] [PATCH 1/5] introduce the kdump logger from the dracut [2] [PATCH 2/5] enable the logger for kdump [3] [PATCH 3/5] kdump.sysconfig: add the kdump logger configurations [4] [PATCH 4/5] kdumpctl: add the '-d' option to enable the kexec loading debugging messages [5] [PATCH 5/5] Improve debugging in the kdump kernel In addition, this patch series won't cause performance degradation, basically this effect can be ignored. I simply checked the result of executing the loading command as follow: [1] before # time kdumpctl start Detected change(s) in the following file(s): /etc/kdump.conf Rebuilding /boot/initramfs-4.18.0-232.el8.x86_64kdump.img Tips: If early kdump is enabled, also require rebuilding the system initramfs to make the changes take effect for early kdump. kexec: loaded kdump kernel Starting kdump: [OK] real 0m9.145s user 0m20.733s sys 0m1.765s [2] after # time kdumpctl start kdump: Detected change(s) in the following file(s): /etc/kdump.conf kdump: Rebuilding /boot/initramfs-4.18.0-232.el8.x86_64kdump.img kdump: Tips: If early kdump is enabled, also require rebuilding the system initramfs to make the changes take effect for early kdump. kdump: kexec: loaded kdump kernel kdump: Starting kdump: [OK] real 0m9.177s user 0m20.784s sys 0m1.901s Changes since v4: [1] Improve and simplify the logger [2] Add the [PATCH 5/5] Improve debugging in the kdump kernel Note: Currently, kexec-tools disable storing logs to journald in order to save memory, please refer to the following changes: +++ b/dracut-module-setup.sh @@ -788,6 +788,8 @@ kdump_install_random_seed() { } ... kdump_install_systemd_conf() { if ! is_fadump_capable && [ "$failure_action" != "shell" ]; then mkdir -p ${initdir}/etc/systemd/journald.conf.d echo "[Journal]" > ${initdir}/etc/systemd/journald.conf.d/kdump.conf echo "Storage=none" >> ${initdir}/etc/systemd/journald.conf.d/kdump.conf ^^^^ If we want to use the journald in kdump kernel, we have to change it to "Storage=auto" or "volatile". Lianbo Jiang (5): introduce the kdump logger from the dracut enable the logger for kdump kdump.sysconfig: add the kdump logger configurations kdumpctl: add the '-d' option to enable the kexec loading debugging messages Improve debugging in the kdump kernel dracut-early-kdump-module-setup.sh | 3 + dracut-early-kdump.sh | 24 +- dracut-kdump.sh | 68 +++--- dracut-module-setup.sh | 4 + kdump-lib-initramfs.sh | 67 ++++-- kdump-lib.sh | 23 +- kdump-logger.sh | 344 +++++++++++++++++++++++++++++ kdump.sysconfig | 16 ++ kdump.sysconfig.aarch64 | 16 ++ kdump.sysconfig.i386 | 16 ++ kdump.sysconfig.ppc64 | 16 ++ kdump.sysconfig.ppc64le | 16 ++ kdump.sysconfig.s390x | 16 ++ kdump.sysconfig.x86_64 | 16 ++ kdumpctl | 241 +++++++++++--------- kexec-tools.spec | 2 + mkdumprd | 12 +- 17 files changed, 731 insertions(+), 169 deletions(-) create mode 100755 kdump-logger.sh -- 2.17.1