Re: [PATCH 00/20] libsas and pm8001 fixes

[Damien Le Moal <damien.lemoal@opensource.wdc.com>]

On 2/11/22 18:24, John Garry wrote:
> On 10/02/2022 22:44, Damien Le Moal wrote:
> 
> Hi Damien,
> 
>>>> Note that without these patches, libzbc test suite result in the
>>>> controller hanging, or in kernel crashes.
>>> Unfortunately I still see the hang on my arm64 system with this series:(
>> That is unfortunate. Any particular command sequence triggering the hang
>> ? Or is it random ? What workload are you running ?
>>
> 
> mount/unmount fails mostly even after as few as one attempt, but then 
> even fdisk -l fails sometimes:

Try with patch 21 of my v2. It does fix a bug for scsi/sas case. That
problem would likely lead to a crash though, but never know...

> root@(none)$ fdisk -l
> [   97.924789] sas: Enter sas_scsi_recover_host busy: 1 failed: 1
> [   97.930652] sas: sas_scsi_find_task: aborting task 0x(____ptrval____)
> [   97.937149] pm80xx0:: mpi_ssp_completion  1937:sas IO status 0x3b
> [   97.943232] pm80xx0:: mpi_ssp_completion  1948:SAS Address of IO 
> Failure Drive:5000c500a7babc61
[...]
> 
> 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 ?

If you are "lucky", it is always the same type of command like for the
NCQ NON DATA in my case. Though on mount, I would only expect a lot of
read commands and not much else. 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 ?

> BTW, this following log needs removal/fixing at some stage by someone:
> 
> [   98.480629] pm80xx: rc= -5
> 
> It's from pm8001_query_task().
> 
> Thanks,
> John


-- 
Damien Le Moal
Western Digital Research