Bug#596419: [xen] BUG at drivers/scsi/aacraid/aachba.c:2825

[Jonathan Nieder <jrnieder@gmail.com>]

Hi Artur,

Artur Linhart wrote:

> It also does not hang up the computer completely, it just freezes the
> keyboard (also the numlock does not react etc.) and services (for example
> concurrent ssh connection to the amchine is no longer usefull), but the
> system itself does still something. There come after some minutes of waiting
> again and again messages, ending by the following call trace (I hope I made
> no mistakes in writing it down from monitor):
> Call Trace:
> [<....>]? smp_call_function_many+0x191/0x1af
> [<....>]? drain_local_pages+0x0/0xd
> [<....>]? smp_call_function+0x20/0x24
[...]
>                         containing also following message:
>
> kernel bug .... ..../source_amd_xen/drivers/scsi/aacraid/aachba.c:2825!
[...]
> Code: 00 00 c7 46 0c 00 00 00 00 c7 46 10 00 00 00 00 c7 46 14 00
> 00 00 00 c7 46 18 00 00 00 00 e8 10 63 fa ff 83 f8 00 41 89 c6 7d 04 <0f> 0b
> eb
> fe 75 08 45 31 e4 e9 9c 00 00 00 49 8b 7f 58 48 89 eb
> RIP [<....>] aac_build_sgraw+0x51/0x10a [aacraid]
>  RSP <ffff88003cd998e0>

Konrad Wilk wrote:

> Based on what Ian analyzed it really looks that we just ran out of DMA buffers and
> the driver didn't try to retry but just bails out.
>
> We can narrow down who is using so many buffers by using the attached debug module
> that when loaded will print out who is using what buffers if
> CONFIG_DMA_API_DEBUG=y is set.

Thanks for reporting this and sorry for the long quiet.  Can you
reproduce this using a sid kernel for the dom0?  I think the only
packages that should be needed for this test from outside squeeze are
the kernel image itself, linux-base, and initramfs-tools.

Jonathan