Re: Potential regression/bug in net/mlx5 driver

["Linux regression tracking #adding (Thorsten Leemhuis)" <regressions@leemhuis.info>]

[TLDR: I'm adding this report to the list of tracked Linux kernel
regressions; the text you find below is based on a few templates
paragraphs you might have encountered already in similar form.
See link in footer if these mails annoy you.]

On 29.03.23 01:08, Paul Moore wrote:
> 
> Starting with the v6.3-rcX kernel releases I noticed that my
> InfiniBand devices were no longer present under /sys/class/infiniband,
> causing some of my automated testing to fail.  It took me a while to
> find the time to bisect the issue, but I eventually identified the
> problematic commit:
> 
>   commit fe998a3c77b9f989a30a2a01fb00d3729a6d53a4
>   Author: Shay Drory <shayd@nvidia.com>
>   Date:   Wed Jun 29 11:38:21 2022 +0300
> 
>    net/mlx5: Enable management PF initialization
> 
>    Enable initialization of DPU Management PF, which is a new loopback PF
>    designed for communication with BMC.
>    For now Management PF doesn't support nor require most upper layer
>    protocols so avoid them.
> 
>    Signed-off-by: Shay Drory <shayd@nvidia.com>
>    Reviewed-by: Eran Ben Elisha <eranbe@nvidia.com>
>    Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
>    Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
> 
> I'm not a mlx5 driver expert so I can't really offer much in the way
> of a fix, but as a quick test I did remove the
> 'mlx5_core_is_management_pf(...)' calls in mlx5/core/dev.c and
> everything seemed to work okay on my test system (or rather the tests
> ran without problem).
> 
> If you need any additional information, or would like me to test a
> patch, please let me know.

Thanks for the report. To be sure the issue doesn't fall through the
cracks unnoticed, I'm adding it to regzbot, the Linux kernel regression
tracking bot:

#regzbot ^introduced fe998a3c77b9f989a30a2a01fb00d3729a6d53a4
#regzbot title net: mlx5: InfiniBand devices were no longer present
#regzbot ignore-activity

This isn't a regression? This issue or a fix for it are already
discussed somewhere else? It was fixed already? You want to clarify when
the regression started to happen? Or point out I got the title or
something else totally wrong? Then just reply and tell me -- ideally
while also telling regzbot about it, as explained by the page listed in
the footer of this mail.

Developers: When fixing the issue, remember to add 'Link:' tags pointing
to the report (the parent of this mail). See page linked in footer for
details.

Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat)
--
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