Support for CPU and memory hotplug for crash is controlled by the CRASH_HOTPLUG configuration option, introduced by this patch. The CRASH_HOTPLUG_ELFCOREHDR_SZ related configuration option is also introduced with this patch. Signed-off-by: Eric DeVolder <eric.devolder@xxxxxxxxxx> --- arch/x86/Kconfig | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 5c2ccb85f2ef..fcaae76fcfe9 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2047,6 +2047,32 @@ config CRASH_DUMP (CONFIG_RELOCATABLE=y). For more details see Documentation/admin-guide/kdump/kdump.rst +config CRASH_HOTPLUG + bool "kernel updates of crash elfcorehdr" + depends on CRASH_DUMP && (HOTPLUG_CPU || MEMORY_HOTPLUG) && KEXEC_FILE + help + Enable the kernel to update the crash elfcorehdr (which contains + the list of CPUs and memory regions) directly when hot plug/unplug + of CPUs or memory. Otherwise userspace must monitor these hot + plug/unplug change notifications via udev in order to + unload-then-reload the crash kernel so that the list of CPUs and + memory regions is kept up-to-date. Note that the udev CPU and + memory change notifications still occur (however, userspace is not + required to monitor for crash dump purposes). + +config CRASH_HOTPLUG_ELFCOREHDR_SZ + depends on CRASH_HOTPLUG + int + default 131072 + help + Specify the maximum size of the elfcorehdr buffer/segment. + The 128KiB default is sized so that it can accommodate 2048 + Elf64_Phdr, where each Phdr represents either a CPU or a + region of memory. + For example, this size can accommodate hotplugging a machine + with up to 1024 CPUs and up to 1024 memory regions (e.g. 1TiB + with 1024 1GiB memory DIMMs). + config KEXEC_JUMP bool "kexec jump" depends on KEXEC && HIBERNATION -- 2.27.0 _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
