ata exception messages

ata exception messages

[Beth Kon]

I'm running an Ubuntu 7.10 guest on a kvm git build (commit
3125ffd6edb9384b3e418fc08fea99e7e1548a96) and am seeing repeated
messages like:

[3393.124685] ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x2
frozen
[3393.127599] ata1.00: cmd ca/00:30:af:c1:48/00:00:00:00:00/e0 tag 0 cdb
0x0 data 4096 out

I see that they're coming from ata_eh_link_report in
drivers/ata/libata-eh.c but am not familiar enough with this code to
understand what the problem is.

Does anyone have any idea what might be causing this? 


-- 
Elizabeth Kon (Beth)
IBM Linux Technology Center
Open Hypervisor Team
email: eak@us.ibm.com

Re: ata exception messages

[Beth Kon]

On Tue, 2008-06-03 at 10:49 -0400, Beth Kon wrote:
> I'm running an Ubuntu 7.10 guest on a kvm git build (commit
> 3125ffd6edb9384b3e418fc08fea99e7e1548a96) and am seeing repeated
> messages like:
> 
> [3393.124685] ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x2
> frozen
> [3393.127599] ata1.00: cmd ca/00:30:af:c1:48/00:00:00:00:00/e0 tag 0 cdb
> 0x0 data 4096 out
> 
> I see that they're coming from ata_eh_link_report in
> drivers/ata/libata-eh.c but am not familiar enough with this code to
> understand what the problem is.
> 
> Does anyone have any idea what might be causing this? 
> 
I discovered that these messages were associated with my disk image being NFS 
mounted. 
-- 
Elizabeth Kon (Beth)
IBM Linux Technology Center
Open Hypervisor Team
email: eak@us.ibm.com

Re: ata exception messages

[Avi Kivity]

Beth Kon wrote:
> On Tue, 2008-06-03 at 10:49 -0400, Beth Kon wrote:
>   
>> I'm running an Ubuntu 7.10 guest on a kvm git build (commit
>> 3125ffd6edb9384b3e418fc08fea99e7e1548a96) and am seeing repeated
>> messages like:
>>
>> [3393.124685] ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x2
>> frozen
>> [3393.127599] ata1.00: cmd ca/00:30:af:c1:48/00:00:00:00:00/e0 tag 0 cdb
>> 0x0 data 4096 out
>>
>> I see that they're coming from ata_eh_link_report in
>> drivers/ata/libata-eh.c but am not familiar enough with this code to
>> understand what the problem is.
>>
>> Does anyone have any idea what might be causing this? 
>>
>>     
> I discovered that these messages were associated with my disk image being NFS 
> mounted. 
>   

Interesting.  Is it an exceptionally slow server (or perhaps, on a lossy 
network)?

I can see how timeouts can annoy the ide driver, but I've never seen 
this myself.

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.

Re: ata exception messages

[Beth Kon]

On Wed, 2008-06-04 at 15:38 +0300, Avi Kivity wrote:
> Beth Kon wrote:
> > On Tue, 2008-06-03 at 10:49 -0400, Beth Kon wrote:
> >   
> >> I'm running an Ubuntu 7.10 guest on a kvm git build (commit
> >> 3125ffd6edb9384b3e418fc08fea99e7e1548a96) and am seeing repeated
> >> messages like:
> >>
> >> [3393.124685] ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x2
> >> frozen
> >> [3393.127599] ata1.00: cmd ca/00:30:af:c1:48/00:00:00:00:00/e0 tag 0 cdb
> >> 0x0 data 4096 out
> >>
> >> I see that they're coming from ata_eh_link_report in
> >> drivers/ata/libata-eh.c but am not familiar enough with this code to
> >> understand what the problem is.
> >>
> >> Does anyone have any idea what might be causing this? 
> >>
> >>     
> > I discovered that these messages were associated with my disk image being NFS 
> > mounted. 
Yes, the network has been misbehaving lately, so could be causing
timeouts.
> 
> Interesting.  Is it an exceptionally slow server (or perhaps, on a lossy 
> network)?
> 
> I can see how timeouts can annoy the ide driver, but I've never seen 
> this myself.
> 
-- 
Elizabeth Kon (Beth)
IBM Linux Technology Center
Open Hypervisor Team
email: eak@us.ibm.com