From: Michael Holzheu <holzheu@xxxxxxxxxxxxxxxxxx> Currently the vmcoreinfo note is only initialized in case of kdump. On s390 it is possible to create kernel dumps with other dump mechanisms than kdump (e.g. via hypervisor dump or stand-alone dump tools). For those dumps it would also be desirable to include the vmcoreinfo data. To accomplish this, with this patch the vmcoreinfo ELF note is always initialized, not only in case of a (kdump) crash. On s390 we will add an ABI defined pointer at a well known address to vmcoreinfo so that dump analysis tools are able to find this information. In particular on s390 we have a tool named zgetdump. With this tool it is possible to convert dump formats on the fly using fuse. E.g. you can mount a s390 stand-alone dump as ELF dump. When this is done, the tool finds the vmcoreinfo in the stand-alone dump via the well known ABI defined address and it creates the respective VMCOREINFO ELF note in the output ELF dump. This then can be used e.g. by makedumpfile for dump filtering. No more need for a vmlinux file with debug information. So this will look like the following: $ zgetdump --mount standalone.dump -f elf /mnt $ ls /mnt dump.elf $ readelf -n /mnt/dump.elf $ ... VMCOREINFO 0x00000474 Unknown note type: (0x00000000) $ makedumpfile -c -d 31 /mnt/dump.elf dump.kdump Signed-off-by: Michael Holzheu <holzheu@xxxxxxxxxxxxxxxxxx> Acked-by: Vivek Goyal <vgoyal@xxxxxxxxxx> --- kernel/kexec.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -1392,24 +1392,23 @@ int __init parse_crashkernel(char *cm } - -void crash_save_vmcoreinfo(void) +static void update_vmcoreinfo_note(void) { - u32 *buf; + u32 *buf = (u32 *) vmcoreinfo_note; if (!vmcoreinfo_size) return; - - vmcoreinfo_append_str("CRASHTIME=%ld", get_seconds()); - - buf = (u32 *)vmcoreinfo_note; - buf = append_elf_note(buf, VMCOREINFO_NOTE_NAME, 0, vmcoreinfo_data, vmcoreinfo_size); - final_note(buf); } +void crash_save_vmcoreinfo(void) +{ + vmcoreinfo_append_str("CRASHTIME=%ld", get_seconds()); + update_vmcoreinfo_note(); +} + void vmcoreinfo_append_str(const char *fmt, ...) { va_list args; @@ -1495,6 +1494,7 @@ static int __init crash_save_vmcoreinfo_ VMCOREINFO_NUMBER(PG_swapcache); arch_crash_save_vmcoreinfo(); + update_vmcoreinfo_note(); return 0; } -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html