Re: [git patches] libata updates for 2.6.34

[Jeff Garzik <jeff@garzik.org>]

On 03/15/2010 09:21 AM, Zeno Davatz wrote:
> On Mon, Mar 15, 2010 at 2:06 PM, Jeff Garzik<jeff@garzik.org>  wrote:
>> On 03/15/2010 03:33 AM, Zeno Davatz wrote:
>>>
>>> On Mon, Mar 15, 2010 at 3:55 AM, Jeff Garzik<jeff@garzik.org>    wrote:
>>>>
>>>> On 03/09/2010 11:26 PM, Tejun Heo wrote:
>>>>>
>>>>> Hello, Linus, Jeff.
>>>>>
>>>>> On 03/10/2010 07:12 AM, Jeff Garzik wrote:
>>>>>>
>>>>>> Coincedentally, it looks like someone else just reported the same
>>>>>> problem, with 2.6.34-rc1.
>>>>>>
>>>>>> It definitely sounds like a race.  READ DMA is a DMA command as the
>>>>>> name
>>>>>> implies, so that eliminates the possibility of polling-related paths in
>>>>>> ata_sff_interrupt (libata-sff.c).
>>>>>>
>>>>>> I'll flip some of my machines to the icky slow boring piix mode, rather
>>>>>> than sexy AHCI mode :) to see if I can reproduce.  I have had a feeling
>>>>>> that we needed a more sophisticated IRQ handling setup, this may be
>>>>>> what
>>>>>> was needed.  Lost interrupt recovery should occur faster than 30
>>>>>> seconds
>>>>>> in any case, and should not require a hard reset if the hardware
>>>>>> functions just fine outside of the lost-interrupt / race that just
>>>>>> occurred.
>>>>>
>>>>> Yeap, there is a race condition with clearing which I don't think we
>>>>> can solve completely but with some modification I think we can at
>>>>> least cover known failure cases.
>>>>>
>>>>> For longer term, I don't think we can solve this by diddling with the
>>>>> SFF registers.  The interface is just way too ancient and horrid to
>>>>> build anything reliable on top of.  I'm planning on implementing
>>>>> smarter IRQ storm handling and stepped timeouts for ATA commands.
>>>>
>>>> A tester on this bug
>>>>         http://bugzilla.kernel.org/show_bug.cgi?id=15537
>>>> seemed to find success with the patch.
>>>
>>> Thanks for the Update!
>>>
>>> I will wait some more and then test rc-2.
>>
>> Can you test the patch, please?
>
> Sure. I done:
>
> /usr/src/linux>  sudo patch -p1<  teo
> patching file drivers/ata/libata-sff.c
> Hunk #1 FAILED at 1667.
> Hunk #2 FAILED at 1700.
> Hunk #3 FAILED at 1718.
> Hunk #4 FAILED at 1770.
> Hunk #5 FAILED at 1792.
> Hunk #6 FAILED at 1801.
> Hunk #7 FAILED at 1818.
> 7 out of 7 hunks FAILED -- saving rejects to file drivers/ata/libata-sff.c.rej
>
> Is that the expected outcome? Can I ignore the "failed" output?

With 7 out of 7 hunks failing, nothing got modified.

Is your source tree an unmodified, vanilla 2.6.34-rc1 tree?

	Jeff