On 10/28/22 15:30, Borislav Petkov wrote:
On Fri, Oct 28, 2022 at 02:26:58PM -0500, Eric DeVolder wrote:config CRASH_MAX_MEMORY_RANGES depends on CRASH_DUMP && KEXEC_FILE && MEMORY_HOTPLUG int default 8192 help For the kexec_file_load path, specify the maximum number of memory regions, eg. as represented by the 'System RAM' entries in /proc/iomem, that the elfcorehdr buffer/segment can accommodate. This value is combined with NR_CPUS and multiplied by Elf64_Phdr size to determine the final buffer size.No, do this: config CRASH_MEMORY_HOTPLUG_SUPPORT depends on CRASH_DUMP && KEXEC_FILE && MEMORY_HOTPLUG help Help text explaining what this feature is this thing will simply get enabled when the user enables MEMORY_HOTPLUG and CRASH_DUMP. and then you do in the code: /* * A comment explaining how the 8192 value has been selected. */ #define CRASH_MAX_MEMORY_RANGES 8192 Thx.
How is this comment? /* * 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 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 memblock size, while resulting in an elfcorehdr * memory buffer/segment size under 1MiB. */ #define CRASH_MAX_MEMORY_RANGES 8192 _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
