Re: [Crash-utility] Question for ARM developers/users w/respect to makedumpfile
----- Original Message -----
But note that in the actual dumpfile header dump, the
"offset_vmcoreinfo" and
"size_vmcoreinfo" kdump_sub_header fields are both set to 0:
...
sub_header_kdump: 9a188c8
phys_base: 80000000
dump_level: 31 (0x1f)
(DUMP_EXCLUDE_ZERO|DUMP_EXCLUDE_CACHE|DUMP_EXCLUDE_CACHE_PRI|DUMP_EXCLUDE_USER_DATA|DUMP_EXCLUDE_FREE)
offset_vmcoreinfo: 0 (0x0)
size_vmcoreinfo: 0 (0x0)
...
I'm wondering whether that's the case with all ARM compressed
kdump files? Or maybe the dumps I have were created during early
development of ARM kexec/kdump? Or is it a bug with the
makedumpfile facility on ARM?
So my question is, do any of you have an ARM compressed kdump that
you can verify has its "offset_vmcoreinfo" and "size_vmcoreinfo"
fields set?
FYI -- actually it's only the size_vmcoreinfo field that would be
equal to 0.
The crash utility's header dump code has a bug that shows the
file offsets as ulong values, which clips the top off on 32-bit
architectures. So after fixing that, what I really see in my
two ARM compressed kdumps is:
sub_header_kdump: 96408f0
phys_base: 80000000
dump_level: 31 (0x1f)
(DUMP_EXCLUDE_ZERO|DUMP_EXCLUDE_CACHE|DUMP_EXCLUDE_CACHE_PRI|DUMP_EXCLUDE_USER_DATA|DUMP_EXCLUDE_FREE)
offset_vmcoreinfo: 17763984736256 (0x102800000000)
size_vmcoreinfo: 0 (0x0
sub_header_kdump: 95ba8f0
phys_base: 80000000
dump_level: 31 (0x1f)
(DUMP_EXCLUDE_ZERO|DUMP_EXCLUDE_CACHE|DUMP_EXCLUDE_CACHE_PRI|DUMP_EXCLUDE_USER_DATA|DUMP_EXCLUDE_FREE)
offset_vmcoreinfo: 17763984736256 (0x102800000000)
size_vmcoreinfo: 0 (0x0)
And interestingly enough, the 0x1028 in the upper 32-bits
is precisely what the offset_vmcoreinfo field *should* be.
So after my ARM kludge patches the two fields, they
look like:
sub_header_kdump: a0a18f0
phys_base: 80000000
dump_level: 31 (0x1f)
(DUMP_EXCLUDE_ZERO|DUMP_EXCLUDE_CACHE|DUMP_EXCLUDE_CACHE_PRI|DUMP_EXCLUDE_USER_DATA|DUMP_EXCLUDE_FREE)
offset_vmcoreinfo: 4136 (0x1028)
size_vmcoreinfo: 1133 (0x46d)
So there's a subtle shift bug in there somewhere w/respect to the
offset_vmcoreinfo value, and for whatever reason the whole
"VMCOREINFO" string from the original ELF Note header is
missing entirely.
Dave