Re: [Crash-utility] crash seek error, failed to read vmcore file
On Tue, 2010-04-20 at 09:14 -0400, Dave Anderson wrote:
----- "Pavan Naregundi" <pavan(a)linux.vnet.ibm.com>
wrote:
The cause for seek errors depends upon the type
of dumpfile.
You didn't mention which type of dumpfile the vmcore
is, so I'll presume that it's either an ELF-format
kdump or a compressed kdump created by makedumpfile.
So presuming that it's a compressed kdump, the seek error
most likely comes from here in read_diskdump() in diskdump.c:
if ((pfn >= dd->header->max_mapnr) || !page_is_ram(pfn))
return SEEK_ERROR;
where the requested physical address pfn values are larger
than the max_mapnr value advertised in the header.
When you do any "crash -d# ...", the dumpfile header will
be dumped first. What does that show?
Dave
Dave,
Dumpfile is compressed kdump created by makedumpfile.
header shows the following values:
max_mapnr: 32768
block_shift: 16
Yes. Adding some debug printf's shows me that (pfn >=
dd->header->max_mapnr) fails.
For example: in the first seek error,
crash: seek error: kernel virtual address: c0000000af715480 type:
"kmem_cache buffer"
paddr: af715480 => pfn=44913
crash -d8 log: http://pastebin.com/qrCvyPfR
Thanks..Pavan