[Crash-utility] crash and the "hugemem" kernel

[Dave Anderson]

"Kurtis D. Rader" wrote:

> Should crash be able to read a RHEL 3 hugemem dump? I've got a x86 14 GiB
> netdump vmcore taken under controlled conditions (e.g., system was booted
> and a crash dump manually invoked) that the crash(1) command doesn't like:

It should work OK, and 4.0-2.7 works OK on my sample hugemem dumpfile.

You didn't mention what version you're trying, so I'm presuming it's ~4.0-2.6.
It's possible the kdump/kexec stuff somehow broke things, but I don't
see anything obvious.

The "vmcore: initialization failed" message gets printed in if memory_source_init()
if netdump_init() fails, i.e., the nd->flags doesn't have the NETDUMP_LOCAL flag
set, but since you're showing it set in the ELF header dump, it doesn't make
any sense to me:

#define VMCORE_VALID()   (nd->flags & (NETDUMP_LOCAL|NETDUMP_REMOTE|KDUMP_LOCAL))

int
netdump_init(char *unused, FILE *fptr)
{
        if (!VMCORE_VALID())
                return FALSE;

        nd->ofp = fptr;
        return TRUE;
}

Anyway, it should be easy enough to debug.  Let me know what you find.

Dave


>
>
>     vmcore: initialization failed
>
> netdump_data:
>                   flags: 5 (NETDUMP_LOCAL|NETDUMP_ELF32)
>                    ndfd: 3
>                     ofp: 4b2b95e0
>             header_size: 4096
>    num_pt_load_segments: 1
>      pt_load_segment[0]:
>             file_offset: 1000
>              phys_start: 0
>                phys_end: 90000000
>          netdump_header: 838a700
>                   elf32: 838a700
>                 notes32: 838a734
>                  load32: 838a754
>                   elf64: 0
>                 notes64: 0
>                  load64: 0
>             nt_prstatus: 838a774
>             nt_prpsinfo: 838a814
>           nt_taskstruct: 838a8a0
>             task_struct: 0
>            switch_stack: 0
>
> Elf32_Ehdr:
>                 e_ident: \177ELF
>       e_ident[EI_CLASS]: 1 (ELFCLASS32)
>        e_ident[EI_DATA]: 1 (ELFDATA2LSB)
>     e_ident[EI_VERSION]: 1 (EV_CURRENT)
>       e_ident[EI_OSABI]: 0 (ELFOSABI_SYSV)
>  e_ident[EI_ABIVERSION]: 0
>                  e_type: 4 (ET_CORE)
>               e_machine: 3 (EM_386)
>               e_version: 1 (EV_CURRENT)
>                 e_entry: 0
>                 e_phoff: 34
>                 e_shoff: 0
>                 e_flags: 0
>                e_ehsize: 34
>             e_phentsize: 20
>                 e_phnum: 2
>             e_shentsize: 0
>                 e_shnum: 0
>              e_shstrndx: 0
> Elf32_Phdr:
>                  p_type: 4 (PT_NOTE)
>                p_offset: 116 (74)
>                 p_vaddr: 0
>                 p_paddr: 0
>                p_filesz: 396 (18c)
>                 p_memsz: 0 (0)
>                 p_flags: 0 ()
>                 p_align: 0
> Elf32_Phdr:
>                  p_type: 1 (PT_LOAD)
>                p_offset: 4096 (1000)
>                 p_vaddr: c0000000
>                 p_paddr: 0
>                p_filesz: 2415919104 (90000000)
>                 p_memsz: 2415919104 (90000000)
>                 p_flags: 7 (PF_X|PF_W|PF_R)
>                 p_align: 4096
> Elf32_Nhdr:
>                n_namesz: 4 ("CORE")
>                n_descsz: 144
>                  n_type: 1 (NT_PRSTATUS)
>                          00000000 00000000 00000000 00000000
>                          00000000 00000000 00000000 00000000
>                          00000000 00000000 00000000 00000000
>                          00000000 00000000 00000000 00000000
>                          00000000 00000000 023b0dc0 00000001
>                          00000001 00000063 00000006 00000063
>                          00000000 00000068 00000068 66d80000
>                          73d80033 ffffffff 021d0950 00000060
>                          00010286 96c15f3c 00000068 00000000
> Elf32_Nhdr:
>                n_namesz: 4 ("CORE")
>                n_descsz: 124
>                  n_type: 3 (NT_PRPSINFO)
>                          00005200 00000000 00000000 00000000
>                          00000000 00000000 00000000 696c6d76
>                          0078756e 00000000 00000000 00000000
>                          00000000 00000000 00000000 00000000
>                          00000000 00000000 00000000 00000000
>                          00000000 00000000 00000000 00000000
>                          00000000 00000000 00000000 00000000
>                          00000000 00000000 00000000
> Elf32_Nhdr:
>                n_namesz: 4 ("CORE")
>                n_descsz: 80
>                  n_type: 4 (NT_TASKSTRUCT)
>                          00000000 00000000 00000000 00000000
>                          00000000 00000000 00000000 00000000
>                          00000000 00000000 00000000 00000000
>                          00000000 00000000 00000000 00000000
>                          00000000 00000000 00000000 00000000
>
> --
> Kurtis D. Rader, Level 3 Linux Support
> ABC Service Center, Linux Change Team
> T/L 775-3714, DID +1 503-578-3714
>
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