Re: [PATCH net-next] net: sparx5: Add spinlock for frame transmission from CPU

[Horatiu Vultur]

The 02/13/2024 09:26, Florian Fainelli wrote:
> 
> On 2/13/24 04:17, Horatiu Vultur wrote:
> > Both registers used when doing manual injection or fdma injection are
> > shared between all the net devices of the switch. It was noticed that
> > when having two process which each of them trying to inject frames on
> > different ethernet ports, that the HW started to behave strange, by
> > sending out more frames then expected. When doing fdma injection it is
> > required to set the frame in the DCB and then make sure that the next
> > pointer of the last DCB is invalid. But because there is no locks for
> > this, then easily this pointer between the DCB can be broken and then it
> > would create a loop of DCBs. And that means that the HW will
> > continuously transmit these frames in a loop. Until the SW will break
> > this loop.
> > Therefore to fix this issue, add a spin lock for when accessing the
> > registers for manual or fdma injection.
> > 
> > Signed-off-by: Horatiu Vultur <horatiu.vultur@xxxxxxxxxxxxx>
> 
> Any reason you targeted 'net-next' rather than 'net', as this appears to
> be clearly a bug fix here?

Yes, it is a bug but it is not something that happens all the
time and I thought this fits more into the lines of 'This could be a
problem ...' therefore I had targeted 'net-next'.
But if you consider that I should target 'net' instead of 'net-next' I
can do that.

> --
> Florian
> 

-- 
/Horatiu