Re: Commit 7eaceaccab5f40 causing boot hang.

[Jens Axboe <jaxboe@fusionio.com>]

On 2011-03-31 11:11, Rob Landley wrote:
> On 03/31/2011 04:02 AM, Jens Axboe wrote:
>> On 2011-03-30 15:52, Rob Landley wrote:
>>> On 03/30/2011 06:38 AM, Jens Axboe wrote:
>>>> On 2011-03-30 08:06, Rob Landley wrote:
>>>>> On 03/29/2011 10:51 AM, Pete Clements wrote:
>>>>>> Quoting Jens Axboe
>>>>>>   > 
>>>>>>   > On 2011-03-29 16:13, Rob Landley wrote:
>>>>>>   > > On 03/29/2011 08:59 AM, Jens Axboe wrote:
>>>>>>   > >> On 2011-03-29 10:52, Rob Landley wrote:
>>>>>>   > >>> I'm booting all this under kvm or qemu, by the way:
>>>>>>   > >>>
>>>>>>   > >>> qemu-system-x86_64 -m 1024 -kernel arch/x86/boot/bzImage \
>>>>>>   > >>>   -hda ~/sid.ext3 -append "root=/dev/hda rw"
>>>>>>   > >>>
>>>>>>   > >>> Sometimes with init=/bin/bash in that last quoted bit.  The root
>>>>>>   > >>> filesystem's debian sid but that's probably not relevant because it
>>>>>>   > >>> worked fine with .38.
>>>>>>   > >>
>>>>>>   > >> Does this help?
>>>>>>   > >>
>>>>>>   > >> diff --git a/drivers/ide/ide-io.c b/drivers/ide/ide-io.c
>>>>>>   > >> index 0e406d73..ca27d30 100644
>>>>>>   > >> --- a/drivers/ide/ide-io.c
>>>>>>   > >> +++ b/drivers/ide/ide-io.c
>>>>>>   > >> @@ -570,8 +570,7 @@ void ide_requeue_and_plug(ide_drive_t *drive, struct request *rq)
>>>>>>   > >>  	spin_unlock_irqrestore(q->queue_lock, flags);
>>>>>>   > >>  
>>>>>>   > >>  	/* Use 3ms as that was the old plug delay */
>>>>>>   > >> -	if (rq)
>>>>>>   > >> -		blk_delay_queue(q, 3);
>>>>>>   > >> +	blk_delay_queue(q, 3);
>>>>>>   > >>  }
>>>>>>   > >>  
>>>>>>   > >>  static int drive_is_ready(ide_drive_t *drive)
>>>>>>   > >>
>>>>>>   > > 
>>>>>>   > > Nope, still hung the same way.
>>>>>>   > 
>>>>>>   > Funky. I'll try and reproduce this tonight.
>>>>>>   > 
>>>>>>   > -- 
>>>>>>   > Jens Axboe
>>>>>>   > 
>>>>>>
>>>>>> I have had a similiar problem (reported earlier) unable to boot.
>>>>>> With git15-18 hung with IDE drives (hda), git19-21 moved the hang down to
>>>>>> the IDE CDROM (hdc). Applied the above patch and now booted into git21 without
>>>>>> any hang and all appears ok.
>>>>>
>>>>> It may have made it better for me, it's hard to tell.
>>>>>
>>>>> I did a fresh pull, re-applied the patch, and tried again with
>>>>> init=/bin/sh and it booted to the shell prompt... which then hung when I
>>>>> did "ls -l /".
>>>>>
>>>>> If I let it boot normally, init announces itself, gives a spurious
>>>>> warning about a fstab field (which it's been doing for a while, my fault
>>>>> but harmless), then hangs.
>>>>>
>>>>>> This is i386, UP.
>>>>>
>>>>> I'm doing x86-64 SMP.
>>>>
>>>> I think we have the same issue the other location. How about this, then:
>>>>
>>>> diff --git a/drivers/ide/ide-io.c b/drivers/ide/ide-io.c
>>>> index 0e406d73..4978ec3 100644
>>>> --- a/drivers/ide/ide-io.c
>>>> +++ b/drivers/ide/ide-io.c
>>>> @@ -549,12 +549,11 @@ plug_device:
>>>>  	spin_unlock_irq(&hwif->lock);
>>>>  	ide_unlock_host(host);
>>>>  plug_device_2:
>>>> +	blk_delay_queue(q, queue_run_ms);
>>>>  	spin_lock_irq(q->queue_lock);
>>>>  
>>>> -	if (rq) {
>>>> +	if (rq)
>>>>  		blk_requeue_request(q, rq);
>>>> -		blk_delay_queue(q, queue_run_ms);
>>>> -	}
>>>>  }
>>>>  
>>>>  void ide_requeue_and_plug(ide_drive_t *drive, struct request *rq)
>>>> @@ -570,8 +569,7 @@ void ide_requeue_and_plug(ide_drive_t *drive, struct request *rq)
>>>>  	spin_unlock_irqrestore(q->queue_lock, flags);
>>>>  
>>>>  	/* Use 3ms as that was the old plug delay */
>>>> -	if (rq)
>>>> -		blk_delay_queue(q, 3);
>>>> +	blk_delay_queue(q, 3);
>>>>  }
>>>>  
>>>>  static int drive_is_ready(ide_drive_t *drive)
>>>>
>>>
>>> Did a fresh pull and applied that patch.  (It conflicts with your
>>> previous one, but looks like it includes it.)
>>>
>>> Now it hangs after the "EXT3-fs: barriers not enabled" line, doesn't
>>> make it to init.
>>
>> I have tried hard to reproduce this, but even stock 2.6.39-rc1 works
>> fine for me here. Setup a KVM image with a debian 6 install, then
>> converted it to IDE and booting it with a custom kernel like you are.
>> Works fine, boots and I can do disk activity tests and it all works.
>>
>> Can you send me your .config?
> 
> It was attached to the first message in this series, here it is again.
> 
> I update it via "make oldconfig" and hold down return.
> 
> I boot it via:
> 
> qemu-system-x86_64 -m 1024 -kernel arch/x86/boot/bzImage \
>   -hda ~/sid.ext3 -append "root=/dev/hda rw"

Much better, I see the hang now! Now to try and diagnose...

-- 
Jens Axboe