From 83698d84aafc08b8fd46188a867fff425da98ad1 Mon Sep 17 00:00:00 2001 From: Coiby Xu Date: Mon, 25 Dec 2023 10:51:41 +0800 Subject: [PATCH] Explain the auto_reset_crashkernel option in more details Resolves: https://issues.redhat.com/browse/RHEL-17451 Upstream: Fedora Conflict: None commit c752cbb2d393c9ae27475f184e2933ff65be50b1 Author: Coiby Xu Date: Wed Dec 6 16:15:50 2023 +0800 Explain the auto_reset_crashkernel option in more details Resolves: https://issues.redhat.com/browse/RHEL-17451 Explain what factors affect the default crashkernel value and ask users to reset it manually if needed. Cc: Baoquan He Cc: Jie Li Acked-by: Baoquan He Signed-off-by: Coiby Xu Signed-off-by: Coiby Xu --- kdump.conf.5 | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/kdump.conf.5 b/kdump.conf.5 index ec28552..3e98cfe 100644 --- a/kdump.conf.5 +++ b/kdump.conf.5 @@ -29,7 +29,20 @@ understand how this configuration file affects the behavior of kdump. .B auto_reset_crashkernel .RS determine whether to reset kernel crashkernel parameter to the default value -or not when kexec-tools is updated or a new kernel is installed. +or not when kexec-tools is updated or a new kernel is installed. The default +crashkernel values are different for different architectures and also take the +following factors into consideration, + - AMD Secure Memory Encryption (SME) and Secure Encrypted Virtualization (SEV) + - Mellanox 5th generation network driver + - aarch64 64k kernel + - Firmware-assisted dump (FADump) + +Since the kernel crasherkernel parameter will be only reset when kexec-tools is +updated or a new kernel is installed, you need to call "kdumpctl +reset-crashkernel [--kernel=path_to_kernel]" if you want to use the default +value set after having enabled features like SME/SEV for a specific kernel. And +you should also reboot the system for the new crashkernel value to take effect. +Also see kdumpctl(8). .B raw .RS