[Qemu-devel] IO errors in guest caused by LTP dio test

[Qemu-devel] IO errors in guest caused by LTP dio test

[Andi Kleen]

Running LTP testcases/kernel/io/direct_io/test_dma_thread_diotest7
causes IO errors in the guest.  There are no IO errors on the host.

Kernel Linux 3.0.0-rc*
Using a standard emulated IDE -hda image.

I tried a few qemu versions, it happens at least with the one
in FC14 and with 0.14. qemu master doesn't boot and ends
with a spinlock lockup.

Writing file _dma_thread_test_0010.tmp.
Writing file _dma_thread_test_0011.tmp.
Writing file _dma_thread_test_0012.tmp.
ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0
ata1.00: BMDMA stat 0x5
ata1.00: failed command: WRITE DMA EXT
ata1.00: cmd 35/00:00:e9:6c:ba/00:04:00:00:00/e0 tag 0 dma 524288 out
         res 41/04:00:e9:6c:ba/04:00:e9:6c:ba/e0 Emask 0x1 (device
         error)
ata1.00: status: { DRDY ERR }
ata1.00: error: { ABRT }
ata1.00: configured for MWDMA2
ata1: EH complete
ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0
ata1.00: BMDMA stat 0x5
ata1.00: failed command: WRITE DMA EXT
ata1.00: cmd 35/00:00:e9:6c:ba/00:04:00:00:00/e0 tag 0 dma 524288 out
         res 41/04:00:e9:6c:ba/04:00:e9:6c:ba/e0 Emask 0x1 (device
         error)
ata1.00: status: { DRDY ERR }
ata1.00: error: { ABRT }
ata1.00: configured for MWDMA2
ata1: EH complete
ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0
ata1.00: BMDMA stat 0x5
ata1.00: failed command: WRITE DMA EXT
ata1.00: cmd 35/00:00:e9:6c:ba/00:04:00:00:00/e0 tag 0 dma 524288 out
         res 41/04:00:e9:6c:ba/04:00:e9:6c:ba/e0 Emask 0x1 (device
         error)
ata1.00: status: { DRDY ERR }
ata1.00: error: { ABRT }
ata1.00: configured for MWDMA2
ata1: EH complete
ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0
ata1.00: BMDMA stat 0x5
ata1.00: failed command: WRITE DMA EXT
ata1.00: cmd 35/00:00:e9:6c:ba/00:04:00:00:00/e0 tag 0 dma 524288 out
         res 41/04:00:e9:6c:ba/04:00:e9:6c:ba/e0 Emask 0x1 (device
         error)
ata1.00: status: { DRDY ERR }
ata1.00: error: { ABRT }
ata1.00: configured for MWDMA2
ata1: EH complete
ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0
ata1.00: BMDMA stat 0x5

-- 
ak@linux.intel.com -- Speaking for myself only

Re: [Qemu-devel] IO errors in guest caused by LTP dio test

[Kevin Wolf]

Am 23.06.2011 01:36, schrieb Andi Kleen:
> 
> Running LTP testcases/kernel/io/direct_io/test_dma_thread_diotest7
> causes IO errors in the guest.  There are no IO errors on the host.
> 
> Kernel Linux 3.0.0-rc*
> Using a standard emulated IDE -hda image.

Couldn't reproduce this in a quick test with a random guest I had
available. What is your complete qemu command line? Is the problem new
with the 3.0 RCs or does it also happen with kernels that my existing
guests are likely to have in use - say, the F15 kernel?

I guess with virtio-blk you don't see the problems?

Kevin

Re: [Qemu-devel] IO errors in guest caused by LTP dio test

[Andi Kleen]

On Mon, Jun 27, 2011 at 05:59:41PM +0200, Kevin Wolf wrote:
> Am 23.06.2011 01:36, schrieb Andi Kleen:
> > 
> > Running LTP testcases/kernel/io/direct_io/test_dma_thread_diotest7
> > causes IO errors in the guest.  There are no IO errors on the host.
> > 
> > Kernel Linux 3.0.0-rc*
> > Using a standard emulated IDE -hda image.
> 
> Couldn't reproduce this in a quick test with a random guest I had
> available. What is your complete qemu command line? Is the problem new

-m 1500M -smp 2               \
-hda ~/qemu/suse-11.1-64.img            \
-kernel arch/x86/boot/bzImage -append "root=/dev/sda1 debug $EXTRA" "$@" 

Could it be related to the image?

suse11.3-64.img: Qemu Image, Format: Qcow , Version: 1 , Disk Size could be: 83886080 * 256 bytes

> with the 3.0 RCs or does it also happen with kernels that my existing
> guests are likely to have in use - say, the F15 kernel?

It happened on older kernels too.
> 
> I guess with virtio-blk you don't see the problems?

Will try later.


-Andi

-- 
ak@linux.intel.com -- Speaking for myself only.

Re: [Qemu-devel] IO errors in guest caused by LTP dio test

[Kevin Wolf]

Am 27.06.2011 18:08, schrieb Andi Kleen:
> On Mon, Jun 27, 2011 at 05:59:41PM +0200, Kevin Wolf wrote:
>> Am 23.06.2011 01:36, schrieb Andi Kleen:
>>>
>>> Running LTP testcases/kernel/io/direct_io/test_dma_thread_diotest7
>>> causes IO errors in the guest.  There are no IO errors on the host.
>>>
>>> Kernel Linux 3.0.0-rc*
>>> Using a standard emulated IDE -hda image.
>>
>> Couldn't reproduce this in a quick test with a random guest I had
>> available. What is your complete qemu command line? Is the problem new
> 
> -m 1500M -smp 2               \
> -hda ~/qemu/suse-11.1-64.img            \
> -kernel arch/x86/boot/bzImage -append "root=/dev/sda1 debug $EXTRA" "$@" 
> 
> Could it be related to the image?
> 
> suse11.3-64.img: Qemu Image, Format: Qcow , Version: 1 , Disk Size could be: 83886080 * 256 bytes

Oh, this is a qcow1 image? Interesting, I didn't expect that people are
still using this format. :-)

Definitely worth trying a raw image or at least qcow2. The old qcow1
format driver hasn't been actively maintained for quite a while now.

>> with the 3.0 RCs or does it also happen with kernels that my existing
>> guests are likely to have in use - say, the F15 kernel?
> 
> It happened on older kernels too.
>>
>> I guess with virtio-blk you don't see the problems?
> 
> Will try later.

Ok, thanks. It looked like an IDE problem at first, but now that you
mention it's a qcow1 image, I think it could just as well be an image
format driver bug.

Kevin

Re: [Qemu-devel] IO errors in guest caused by LTP dio test

[Kevin Wolf]

Am 28.06.2011 10:50, schrieb Kevin Wolf:
> Am 27.06.2011 18:08, schrieb Andi Kleen:
>> On Mon, Jun 27, 2011 at 05:59:41PM +0200, Kevin Wolf wrote:
>>> Am 23.06.2011 01:36, schrieb Andi Kleen:
>>>>
>>>> Running LTP testcases/kernel/io/direct_io/test_dma_thread_diotest7
>>>> causes IO errors in the guest.  There are no IO errors on the host.
>>>>
>>>> Kernel Linux 3.0.0-rc*
>>>> Using a standard emulated IDE -hda image.
>>>
>>> Couldn't reproduce this in a quick test with a random guest I had
>>> available. What is your complete qemu command line? Is the problem new
>>
>> -m 1500M -smp 2               \
>> -hda ~/qemu/suse-11.1-64.img            \
>> -kernel arch/x86/boot/bzImage -append "root=/dev/sda1 debug $EXTRA" "$@" 
>>
>> Could it be related to the image?
>>
>> suse11.3-64.img: Qemu Image, Format: Qcow , Version: 1 , Disk Size could be: 83886080 * 256 bytes
> 
> Oh, this is a qcow1 image? Interesting, I didn't expect that people are
> still using this format. :-)
> 
> Definitely worth trying a raw image or at least qcow2. The old qcow1
> format driver hasn't been actively maintained for quite a while now.
> 
>>> with the 3.0 RCs or does it also happen with kernels that my existing
>>> guests are likely to have in use - say, the F15 kernel?
>>
>> It happened on older kernels too.
>>>
>>> I guess with virtio-blk you don't see the problems?
>>
>> Will try later.
> 
> Ok, thanks. It looked like an IDE problem at first, but now that you
> mention it's a qcow1 image, I think it could just as well be an image
> format driver bug.

No news is good news? Does it work with a different image format?

Kevin