Re: Something corrupts raid5 disks slightly during reboot

[Willy Tarreau <willy@w.ods.org>]

Hi Ville,

On Wed, Jan 14, 2004 at 04:46:46PM +0200, Ville Herva wrote:
 
>   - I tried booting from 2.6.1 single user mode to 2.6.1 single user
>     mode (booting with sysrq-b to avoid shutdown process):
>        ->  The corruption on /dev/hdg happens like with 2.2 and 2.4
> 
>   - I booted from 2.6.1 single user mode to 2.6.1 single user
>     mode with kexec patch to avoid entering BIOS in between
>        ->  The corruption DOES NOT happen
> 
> I'm pretty much out of ideas.

To me, it proves that the bios triggers the problem. It could also be in
the device enumeration functions or device initialization that it does
this thing. Perhaps even a more nasty thing such as a pending DMA write
which completes during a device reset. That's very odd anyway. I don't
quite remember well all your setup. Have you tried enabling/disabling
shadow ram/caching on bios regions to check if a faster/slower code execution
in the bios changes something ? Also do it on additionnal ROMs if you have
an onboard bios on your secondary controller.

I'm also getting stuck without any other idea :-/

Regards,
Willy