Re: [4.5-rc4 Regression] qla2xxx: Add irq affinity notification

From: Quinn Tran
Date: Mon Apr 11 2016 - 14:21:26 EST


Joe,

How do I get access to this specific Ubuntu kernel where the bug is found? Is there stack trace/bug report that you could share? Any data would be helpful. Thanks.

In the mean time, I will download 4.5 rc4 to re-verify.

Regards,
Quinn Tran






-----Original Message-----
From: Joseph Salisbury <joseph.salisbury@xxxxxxxxxxxxx>
Date: Monday, April 11, 2016 at 10:26 AM
To: Quinn Tran <quinn.tran@xxxxxxxxxx>
Cc: Dept-Eng QLA2xxx Upstream <qla2xxx-upstream@xxxxxxxxxx>, "jejb@xxxxxxxxxxxxxxxxxx" <jejb@xxxxxxxxxxxxxxxxxx>, "Martin K. Petersen" <martin.petersen@xxxxxxxxxx>, linux-scsi <linux-scsi@xxxxxxxxxxxxxxx>, linux-kernel <linux-kernel@xxxxxxxxxxxxxxx>, "hch@xxxxxx" <hch@xxxxxx>, "bart.vanassche@xxxxxxxxxxx" <bart.vanassche@xxxxxxxxxxx>, Himanshu Madhani <himanshu.madhani@xxxxxxxxxx>, Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
Subject: [4.5-rc4 Regression] qla2xxx: Add irq affinity notification

>Hello Quinn,
>
>A kernel bug report was opened against Ubuntu [0]. After a kernel
>bisect, it was found that reverting the following commit resolved this bug:
>
>commit cdb898c52d1dfad4b4800b83a58b3fe5d352edde
>Author: Quinn Tran <quinn.tran@xxxxxxxxxx>
>Date: Thu Dec 17 14:57:05 2015 -0500
>
> qla2xxx: Add irq affinity notification
>
>
>However, the prior commit also required the following three commits to
>also be reverted:
>
>commit 5327c7dbd1a7fd980608f44789076a636e5ee5fc
>Author: Quinn Tran <quinn.tran@xxxxxxxxxx>
>Date: Wed Feb 10 18:59:14 2016 -0500
>
> qla2xxx: use TARGET_SCF_USE_CPUID flag to indiate CPU Affinity
>
>commit 9095adaab8c1d82707e4e9961b6ad79b62f3361b
>Author: Quinn Tran <quinn.tran@xxxxxxxxxx>
>Date: Wed Feb 10 18:59:13 2016 -0500
>
> target/transport: add flag to indicate CPU Affinity is observed
>
>commit fb3269baf4ecc2ce6d17d4eb537080035bdf6d5b
>Author: Quinn Tran <quinn.tran@xxxxxxxxxx>
>Date: Thu Dec 17 14:57:06 2015 -0500
>
> qla2xxx: Add selective command queuing
>
>
>
>The regression was introduced as of v4.5-rc4.
>
>I was hoping to get your feedback, since you are the patch author. The
>dependant reverts all look like they are improving cpu affinity, which
>would likely impact performance. Do you thing there is a way forward
>instead of the reverts, or would it be best to submit a revert request?
>
>
>Thanks,
>
>Joe
>
>
>[0] http://pad.lv/1554003
>
>