Re: [PATCH V2 resend] libata:fix kernel panic when hotplug

[Dan Williams]

On Mon, Jun 20, 2016 at 6:22 PM, Martin K. Petersen
<martin.petersen@xxxxxxxxxx> wrote:
>>>>>> "Tejun" == Tejun Heo <tj@xxxxxxxxxx> writes:
>
>>> In fact,we don't need libata to deal with hotplug in sas environment.
>>> So we can't run ata hotplug task when ata port is sas host.
>
> Tejun> Martin, can you please confirm whether the above is true.  If so,
> Tejun> I'll route the patch through libata w/ stable cc'd.
>
> Not exactly a libsas expert. James? Dan?

While it is true that libsas itself handles adding / removing devices
we have historically avoided this conflict because
ATA_PFLAG_SCSI_HOTPLUG is never set for libsas ata_ports.  So the bug
/ behavior change is that  ATA_PFLAG_SCSI_HOTPLUG gets set in the
first place.  Ignoring it is a band-aid / not the real fix afaics.