Hi Damien,
Sometimes I get TMF timeouts, which is a bad situation. I guess it's a
subtle driver bug, but where ....?
What is the command failing ? Always the same ? Can you try adding scsi
trace to see the commands ?
This is the same issue I have had since day #1.
Generally mount/unmount or even fdisk -l fails after booting into
miniramfs. I wouldn't ever try to boot a distro.
busybox ?
Yes
If you are "lucky", it is always the same type of command like for the
NCQ NON DATA in my case.
I'm just trying SAS disks to start with - so it's an SCSI READ command.
SATA/STP support is generally never as robust for SAS HBAs (HW and LLD
bugs are common - as this series is evidence) so I start on something
more basic - however SATA/STP also has this issue.
The command is sent successfully but just never completes. Then
sometimes the TMFs for error handling timeout and sometimes succeed. I
don't have much to do on....
No SAS bus analyzer lying in a corner of the office ? :)
That could help...
None unfortunately
I will go to the office Monday. So I will get a chance to add SAS drives
to my setup to see what I get. I have only tested with SATA until now.
My controller is not the same chip as yours though.
jfyi, Ajish, cc'ed, from microchip says that they see the same issue on
their arm64 system. Unfortunately fixing it is not a priority for them.
So it is something which arm64 is exposing.
And I tried an old kernel - like 4.10 - on the same board and the pm8001
driver was working somewhat reliably (no hangs). It just looks like a
driver issue.
I'll have a look at the driver code again if I get a chance. It might be
a DMA issue.
Though on mount, I would only expect a lot of
read commands and not much else.
Yes, and it is commonly the first SCSI read command which times out. It
reliably breaks quite early. So I can think we can rule out issues like
memory barriers/timing.
There may be some writes and a flush
too, so there will be "data" commands and "non data" commands. It may be
an issue with non-data commands too ?
Not sure on that. I guess it isn't.
Anything special with the drives you are using ? Have you tried other
drives to see if you get lucky ?
I think that the drives are ok. On the same board I originally had them
plugged in the hisi_sas HBA and no issues.
thanks,
john
