Re: [PATCH 0/2] mpt{2,3}sas remove disconnected phys on topology change

From: Sreekanth Reddy
Date: Tue Dec 02 2014 - 09:14:45 EST


Ok. Thanks Tomas, I will follow the same and will send the revert
patch to Upstream.

Thanks,
Sreekanth.

On Tue, Dec 2, 2014 at 7:37 PM, Tomas Henzl <thenzl@xxxxxxxxxx> wrote:
> Hi Sreekanth,
>
> I think this should be handled as any other change with an usual
> patch sent to the list, 'git revert 3520f9c779' and 'git revert 963ba22b90'
> will create the patches for you.
>
> Cheers,
> Tomas
>
> On 12/02/2014 02:18 PM, Sreekanth Reddy wrote:
>> Hi James/Chris
>>
>> We are observing below issue due to this patch set code changes
>>
>> Issue Description:
>> Drives connected Enclosure/Expander won't be visible to the OS if any
>> one remove and add expander cable with in DMD (Device Missing Delay) time
>> period (also if any power-off and power-on the Enclosure with in the DMD
>> period).
>>
>> i.e.
>> Due to this code changes; driver will unregister the Enclosure port or
>> target PHY with SCSI transport layer, whenever driver receives "SAS
>> TOPOLOGY CHANGE LIST EVENT" with reason code set to "PHY link status
>> change" and phy link rate is Zero. Firmware usually send this type of "SAS
>> TOPOLOGY CHANGE LIST EVENT" event whenever drive is missing. but still
>> here DMD timer has not yet expired so normally driver should not
>> unregister the target with the SCSI transport layer instead it will move
>> the state of the drive to blocked state (so it won't receive any IOs from
>> SML for this drive).
>>
>> Normally, Driver should only unregister the target with SCSI transport
>> layer only when driver receives "SAS TOPOLOGY CHANGE LIST EVENT" with
>> reason code set to "Target Remove". Firmware will send this event when the
>> DMD timer expires for the missing drive. If drive comes back with in the
>> DMD period then firmware won't send this target remove event and so driver
>> won't unregister the target drive with the SCSI transport layer. Driver
>> will just unblock the target drive to start IOs to this drive.
>>
>> So, can you please revert this patch set changes back in the latest
>> upstream kernel and if possible on stable kernels.
>> I checked with the Redhat team and there are fine to revert back these
>> patch set changes.
>>
>> Regards,
>> Sreekanth
>>
>>> -----Original Message-----
>>> From: Jan Vesely [mailto:jvesely@xxxxxxxxxx]
>>> Sent: Thursday, August 01, 2013 3:31 PM
>>> To: linux-scsi@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
>>> Cc: Jan Vesely; Nandigama, Nagalakshmi; Reddy, Sreekanth; Tomas Henzl
>>> Subject: [PATCH 0/2] mpt{2,3}sas remove disconnected phys on topology
>>> change
>>>
>>> From: Jan Vesely <jvesely@xxxxxxxxxx>
>>>
>>> These two patches add phy removal on link loss. This change keeps sysfs
>>> up- to-date with actually connected phys. Without these patches,
>>> disconnected phys remain listed under their former ports.
>>>
>>> tested on both mpt2sas and mpt3sas hw.
>>>
>>> CC: Nagalakshmi Nandigama <Nagalakshmi.Nandigama@xxxxxxx>
>>> CC: Sreekanth Reddy <Sreekanth.Reddy@xxxxxxx>
>>> CC: Tomas Henzl <thenzl@xxxxxxxxxx>
>>> Signed-off-by: Jan Vesely <jvesely@xxxxxxxxxx>
>>>
>>> Jan Vesely (2):
>>> mpt2sas: Remove phys on topology change.
>>> mpt3sas: Remove phys on topology change
>>>
>>> drivers/scsi/mpt2sas/mpt2sas_transport.c | 5 ++++-
>>> drivers/scsi/mpt3sas/mpt3sas_transport.c | 5 ++++-
>>> 2 files changed, 8 insertions(+), 2 deletions(-)
>>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
>> the body of a message to majordomo@xxxxxxxxxxxxxxx
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/