Message-ID: <4D931634.5030807@fusionio.com>
Date: Wed, 30 Mar 2011 13:38:28 +0200
From: Jens Axboe <jaxboe@fusionio.com>
MIME-Version: 1.0
To: Rob Landley <rlandley@parallels.com>
CC: Pete Clements <clem@clem.clem-digital.net>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        "linux-ide@vger.kernel.org" <linux-ide@vger.kernel.org>
Subject: Re: Commit 7eaceaccab5f40 causing boot hang.
References: <201103291551.p2TFpDqZ001692@clem.clem-digital.net> <4D92C874.7040104@parallels.com>
In-Reply-To: <4D92C874.7040104@parallels.com>
Content-Type: text/plain; charset="ISO-8859-1"
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 3279
Lines: 101

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)

-- 
Jens Axboe

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/