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Diffstat (limited to 'kernel/Kconfig.kexec')
| -rw-r--r-- | kernel/Kconfig.kexec | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/kernel/Kconfig.kexec b/kernel/Kconfig.kexec index 701cd5336f4f..727190571544 100644 --- a/kernel/Kconfig.kexec +++ b/kernel/Kconfig.kexec @@ -112,4 +112,35 @@ config CRASH_DUMP For s390, this option also enables zfcpdump. See also <file:Documentation/s390/zfcpdump.rst> +config CRASH_HOTPLUG + bool "Update the crash elfcorehdr on system configuration changes" + default y + depends on CRASH_DUMP && (HOTPLUG_CPU || MEMORY_HOTPLUG) + depends on ARCH_SUPPORTS_CRASH_HOTPLUG + help + Enable direct update to the crash elfcorehdr (which contains + the list of CPUs and memory regions to be dumped upon a crash) + in response to hot plug/unplug or online/offline of CPUs or + memory. This is a much more advanced approach than userspace + attempting that. + + If unsure, say Y. + +config CRASH_MAX_MEMORY_RANGES + int "Specify the maximum number of memory regions for the elfcorehdr" + default 8192 + depends on CRASH_HOTPLUG + help + For the kexec_file_load() syscall path, specify the maximum number of + memory regions that the elfcorehdr buffer/segment can accommodate. + These regions are obtained via walk_system_ram_res(); eg. the + 'System RAM' entries in /proc/iomem. + This value is combined with NR_CPUS_DEFAULT and multiplied by + sizeof(Elf64_Phdr) to determine the final elfcorehdr memory buffer/ + segment size. + The value 8192, for example, covers a (sparsely populated) 1TiB system + consisting of 128MiB memblocks, while resulting in an elfcorehdr + memory buffer/segment size under 1MiB. This represents a sane choice + to accommodate both baremetal and virtual machine configurations. + endmenu |