Re: [REGRESSION] qla2xxx: tape drive not removed after unplug FC cable

[Arun Easi]

Hi Tony,

Thanks for reporting the issue. We are trying to recreate this issue in 
house. I will reach out to you for logs, if we cannot repro. Typically, we 
get sufficient context to the issue when the problem is reproduced with 
module parameter "ql2xextended_error_logging=1".

Anyway, I will let you know the status.

Regards,
-Arun

On Wed, 25 May 2022, 3:03pm, Tony Battersby wrote:

> #regzbot introduced: 44c57f205876
> 
> I have several different QLogic FC HBAs (8, 16, 32 Gbps) and several
> different FC LTO tape drives (IBM Ultrium 8 & 9).  When I plug in the FC
> cable, the tape drive shows up as a SCSI device as expected.  With older
> kernels, when I unplug the FC cable, the tape drive SCSI device would
> disappear after about 30 seconds.  But with newer kernels (including
> 5.18), when I unplug the FC cable, the tape drive SCSI device never
> disappears.  I have bisected the change in behavior to the following
> commit in kernel 5.15:
> 
> 44c57f205876 ("scsi: qla2xxx: Changes to support FCP2 Target")
> 
> This commit has been backported to various -stable kernels, so they are
> also affected.
> 
> When testing with two different tape drives:
> 1) Plug FC cable into tape drive A.  Tape drive A shows up as a SCSI device.
> 2) Unplug FC cable; wait 60 seconds.  Tape drive A does not disappear.
> 3) Plug FC cable into tape drive B.  Tape drive A disappears 30 seconds
> later, but tape drive B does not show up.
> 4) Unplug FC cable and plug it back into tape drive B.  Tape drive B
> shows up as a SCSI device.
> 
> So I can actually make a tape drive disappear by plugging the cable into
> a different tape drive, but then I have to reseat the cable again to
> make the new tape drive show up.
> 
> lspci -n
> 83:00.0 0c04: 1077:2031 (rev 02)
> 83:00.1 0c04: 1077:2031 (rev 02)
> 
> When plugging in cable:
> qla2xxx [0000:83:00.1]-500a:7: LOOP UP detected (8 Gbps).
> 
> When unplugging cable with old kernel:
> qla2xxx [0000:83:00.1]-500b:7: LOOP DOWN detected (2 7 0 0).
> rport-7:0-2: blocked FC remote port time out: removing target and saving binding
> 
> When unplugging cable with new kernel:
> qla2xxx [0000:83:00.1]-500b:7: LOOP DOWN detected (2 7 0 0).
> 
> /sys/class/fc_remote_ports/rport-*/
> dev_loss_tmo: 30
> supported_classes: Class 3
> port_state: Online
> (port_state remains Online even when FC cable unplugged)
> 
> /proc/scsi/scsi
> Host: scsi7 Channel: 00 Id: 01 Lun: 00
>   Vendor: IBM      Model: ULTRIUM-HH8      Rev: K4K1
>   Type:   Sequential-Access                ANSI  SCSI revision: 06
> 
> Tony Battersby
> Cybernetics
> 
>