Latest kernel (3.9 and newer) is aware of memmap=resetusablemap (instead of memmap=exactmap). In this case the kdump kernel uses unusable memory areas (reserved, ACPI, NVS) as passed by e820 table via kexec. This is done in kexec/firmware_memmap.c (collected from /sys/firmware/memmap from the original kernel). Therefore reserved memory areas need not to get passed via memmap=x#y or memmap=x$y anymore.
With this kernel version on, it is also possible to pass several memmap= options via one comma separated memmap=resetusablemap,x@y,... kernel parameter. This patch enables kexec to make use of it. Signed-off-by: Thomas Renninger <[email protected]> --- kexec/arch/i386/crashdump-x86.c | 46 ++++++++++++++++++++++++++++---------- 1 files changed, 34 insertions(+), 12 deletions(-) diff --git a/kexec/arch/i386/crashdump-x86.c b/kexec/arch/i386/crashdump-x86.c index a900b03..9bba8d1 100644 --- a/kexec/arch/i386/crashdump-x86.c +++ b/kexec/arch/i386/crashdump-x86.c @@ -676,6 +676,8 @@ static void ultoa(unsigned long i, char *str) } } +static int new_memmap_syntax; + /* Adds the appropriate memmap= options to command line, indicating the * memory regions the new kernel can use to boot into. */ static int cmdline_add_memmap(char *cmdline, struct memory_range *memmap_p) @@ -684,8 +686,23 @@ static int cmdline_add_memmap(char *cmdline, struct memory_range *memmap_p) unsigned long min_sizek = 100; char str_mmap[256], str_tmp[20]; - /* Exact map */ - strcpy(str_mmap, " memmap=exactmap"); + /* + * kernel is aware of comma separated memmap= + * and memmap=resetusablemap boot param, reserved memory + * areas are taken over from original e820 boot map and must + * not be passed anymore, only usable memory areas: + * old syntax: memmap=exactmap memmap=x@y memmap=w@z memmap=k#f + * new syntax: memmap=resetusablemap,x@y,w@z + */ + if (kv_to_load >= KERNEL_VERSION(3, 7, 0)) + new_memmap_syntax = 1; + + if (new_memmap_syntax) + strcpy(str_mmap, " memmap=resetusablemap"); + else + /* Exact map */ + strcpy(str_mmap, " memmap=exactmap"); + len = strlen(str_mmap); cmdlen = strlen(cmdline) + len; if (cmdlen > (COMMAND_LINE_SIZE - 1)) @@ -704,7 +721,10 @@ static int cmdline_add_memmap(char *cmdline, struct memory_range *memmap_p) * up precious command line length. */ if ((endk - startk) < min_sizek) continue; - strcpy (str_mmap, " memmap="); + if (new_memmap_syntax) + strcpy (str_mmap, ","); + else + strcpy (str_mmap, " memmap="); ultoa((endk-startk), str_tmp); strcat (str_mmap, str_tmp); strcat (str_mmap, "K@"); @@ -1035,15 +1055,17 @@ int load_crashdump_segments(struct kexec_info *info, char* mod_cmdline, cmdline_add_efi(mod_cmdline); cmdline_add_elfcorehdr(mod_cmdline, elfcorehdr); - /* Inform second kernel about the presence of ACPI tables. */ - for (i = 0; i < CRASH_MAX_MEMORY_RANGES; i++) { - unsigned long start, end; - if ( !( mem_range[i].type == RANGE_ACPI - || mem_range[i].type == RANGE_ACPI_NVS) ) - continue; - start = mem_range[i].start; - end = mem_range[i].end; - cmdline_add_memmap_acpi(mod_cmdline, start, end); + if (!new_memmap_syntax) { + /* Inform second kernel about the presence of ACPI tables. */ + for (i = 0; i < CRASH_MAX_MEMORY_RANGES; i++) { + unsigned long start, end; + if ( !( mem_range[i].type == RANGE_ACPI + || mem_range[i].type == RANGE_ACPI_NVS) ) + continue; + start = mem_range[i].start; + end = mem_range[i].end; + cmdline_add_memmap_acpi(mod_cmdline, start, end); + } } return 0; } -- 1.7.6.1 _______________________________________________ kexec mailing list [email protected] http://lists.infradead.org/mailman/listinfo/kexec
