Re: 2.6.25-rc1 xen pvops regression

Joel Becker
2008-02-17T06:31:28Z

On Sat, Feb 16, 2008 at 10:46:23PM +1100, Jeremy Fitzhardinge wrote:
> Joel Becker wrote:
>> ksymoops is no help at all, but I got these from objdump of
>> vmlinux:
>>
>> c04040bd xen_set_pte
>> c0417ab6 set_pte_present
>> c040288f set_bit
>> c040299a __raw_spin_unlock
>> c0403270 __set_64bit
>
> (My usual technique is use "gdb vmlinux" and "x/i 0x...." to do the
> lookup.)

Thanks for the tip!

> Unfortunately that doesn't narrow down what the kernel was actually
> trying to do at the time. Clearly a set_pte; looks like someone is
> trying to create a writable mapping of an existing pte page.
>
> Does "console=hvc0 earlyprintk=xen" on the kernel command line give any
> clue about how far it gets before crashing?

Console is already hvc0, but earlyprintk gets us:

--8<-----------------------------------------------------------------
Reserving virtual address space above 0xf57fe000
Linux version 2.6.25-rc2-bisectme (jlbec@ca-build23.us.oracle.com) (gcc
version 4.1.2 20070626 (Red Hat 4.1.2-14)) #21 SMP Fri Feb 15 16:28:35
PST 2008
ACPI in unprivileged domain disabled
BIOS-provided physical RAM map:
Xen: 0000000000000000 - 0000000078000000 (usable)
console [xenboot0] enabled
1192MB HIGHMEM available.
727MB LOWMEM available.
Started domain ca-test58
Scan SMP from c0000000 for 1024 bytes.
Scan SMP from c009fc00 for 1024 bytes.
Scan SMP from c00f0000 for 65536 bytes.
NX (Execute Disable) protection: active
Zone PFN ranges:
DMA 0 -> 4096
Normal 4096 -> 186366
HighMem 186366 -> 491520
Movable zone start PFN for each node
early_node_map[1] active PFN ranges
0: 0 -> 491520
-->8-----------------------------------------------------------------

That's it.

Joel

--

"The nearest approach to immortality on Earth is a government
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Joel Becker
Principal Software Developer
Oracle
E-mail: joel.becker@oracle.com
Phone: (650) 506-8127