On 04/11/2016 05:28 PM, Quinn Tran wrote:
> Joe,
>
> I see the crash point. We’re accessing Null pointer. The adapter in use is
> an older 4G adapter, where it does not have MSIX support. We’re tripping
> over the same shared code segment. The following is the propose fix. Let me
> know if it works. I’ll will follow up with a patch for upstream submission.
>
> Thanks.
>
> diff --git a/drivers/scsi/qla2xxx/qla_isr.c b/drivers/scsi/qla2xxx/qla_isr.c
> index 4af9547..79469de 100644
> --- a/drivers/scsi/qla2xxx/qla_isr.c
> +++ b/drivers/scsi/qla2xxx/qla_isr.c
> @@ -2552,7 +2552,7 @@ void qla24xx_process_response_queue(struct
> scsi_qla_host *vha,
> if (!vha->flags.online)
> return;
>
> - if (rsp->msix->cpuid != smp_processor_id()) {
> + if (rsp->msix && (rsp->msix->cpuid != smp_processor_id())) {
> /* if kernel does not notify qla of IRQ's CPU change,
> * then set it here.
> */
>
>
>
>
> Regards,
> Quinn Tran
Good news, testing with your new patch resolved the bug and did not
require any reverts. Thanks for the quick response!
Testing results in comment #39: http://pad.lv/1554003
>
>
>
>
>
>
> -----Original Message-----
> From: Joseph Salisbury <[email protected]>
> Date: Monday, April 11, 2016 at 11:41 AM
> To: Quinn Tran <[email protected]>
> Cc: Dept-Eng QLA2xxx Upstream <[email protected]>,
> "[email protected]" <[email protected]>, "Martin K. Petersen"
> <[email protected]>, linux-scsi <[email protected]>,
> linux-kernel <[email protected]>, "[email protected]" <[email protected]>,
> "[email protected]" <[email protected]>, Himanshu Madhani
> <[email protected]>, Nicholas Bellinger <[email protected]>
> Subject: Re: [4.5-rc4 Regression] qla2xxx: Add irq affinity notification
>
>> On 04/11/2016 01:48 PM, Quinn Tran wrote:
>>> 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.
>> The git tree for the specific Ubuntu kernel that exhibits this bug can
>> be found here:
>> git://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/xenial
>>
>> The bug can be found here, and has screen shots of the panic as well as
>> dmesg under the "Attachments" header:
>> http://pad.lv/1554003
>>
>> Just let me know if additional debug information is needed.
>>
>>
>>> In the mean time, I will download 4.5 rc4 to re-verify.
>>>
>>> Regards,
>>> Quinn Tran
>>>
>>>
>>>
>>>
>>>
>>>
>>> -----Original Message-----
>>> From: Joseph Salisbury <[email protected]>
>>> Date: Monday, April 11, 2016 at 10:26 AM
>>> To: Quinn Tran <[email protected]>
>>> Cc: Dept-Eng QLA2xxx Upstream <[email protected]>,
>>> "[email protected]" <[email protected]>, "Martin K. Petersen"
>>> <[email protected]>, linux-scsi <[email protected]>,
>>> linux-kernel <[email protected]>, "[email protected]" <[email protected]>,
>>> "[email protected]" <[email protected]>, Himanshu Madhani
>>> <[email protected]>, Nicholas Bellinger <[email protected]>
>>> 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 <[email protected]>
>>>> 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 <[email protected]>
>>>> 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 <[email protected]>
>>>> Date: Wed Feb 10 18:59:13 2016 -0500
>>>>
>>>> target/transport: add flag to indicate CPU Affinity is observed
>>>>
>>>> commit fb3269baf4ecc2ce6d17d4eb537080035bdf6d5b
>>>> Author: Quinn Tran <[email protected]>
>>>> 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
>>>>
>>>>
