[Crash-utility] [help]crash can't anaylyse xen guest paravirtulized linux vmcore

[Dave Anderson]

----- Original Message -----
> 
> 
> my crash can analyse xen hvm guest linux memory dump core :
> 
> 
> SLES11:/mnt/sles10.2_crash # crash32 -s vmlinux-debug sles10.img
> WARNING: kernel version inconsistency between vmlinux and dumpfile
> 
> crash32> bt
> PID: 0 TASK: c02d8280 CPU: 0 COMMAND: "swapper"
> #0 [c0329f9c] schedule at c0288d6d
> #1 [c0329ffc] is386 at c0100194

OK, so you're saying that it's only an issue with SLES paravirtualized
kernels?

I compared the output of "crash -d8" output using a 2.6.18-152.el5xen kernel
(fully virtualized with the old Xen patch), and the sequence is pretty
much identical, other than the .xen_p2m and .xen_pages Elf64_Shdr's are
in a different order in the dumpfile.  But that shouldn't make a difference,
because crash doesn't expect them in any particular order.

So again, the only thing I can see is that the page that contains the
"max_pfn" symbol is full of zeroes -- which is obviously wrong -- and
then while walking the page tables to find the page containing the
"phys_to_machine_mapping" symbol, it finds the page table that should
contain a PTE that points to the page containing it, but the PTE entry
is zero.  Although other PTEs in the page table page do contain legitimate
PTEs.

The only thing I can think of is that the vmlinux file that you're using
doesn't match the dumpfile, i.e., the "max_pfn" and "phys_to_machine_mapping"
symbols from the vmlinux file are not the same as the kernel represented by
the dumpfile?

Dave