Re: [PATCH net-next v5 2/4] net: dsa: mxl862xx: move phylink stubs to mxl862xx-phylink.c

[Simon Horman <horms@kernel.org>]

On Thu, Jun 11, 2026 at 02:28:56PM +0100, Daniel Golle wrote:
> On Thu, Jun 11, 2026 at 02:07:51PM +0100, Simon Horman wrote:
> > This is an AI-generated review of your patch. The human sending this
> > email has considered the AI review valid, or at least plausible.
> > Full review at: https://sashiko.dev
> > ---
> > net: dsa: mxl862xx: move phylink stubs to mxl862xx-phylink.c
> > 
> > Move the phylink MAC operations and get_caps callback from mxl862xx.c
> > into a dedicated mxl862xx-phylink.c file. This prepares for the SerDes
> > PCS implementation which adds substantial phylink/PCS code.
> > 
> > > diff --git a/drivers/net/dsa/mxl862xx/mxl862xx.c b/drivers/net/dsa/mxl862xx/mxl862xx.c
> > > index 2f22adedfbf67..a193f3c07d359 100644
> > > --- a/drivers/net/dsa/mxl862xx/mxl862xx.c
> > > +++ b/drivers/net/dsa/mxl862xx/mxl862xx.c
> > 
> > [ ... ]
> > 
> > [Severity: Critical]
> > This is a pre-existing issue, but the crc_err_work can execute after
> > dsa_unregister_switch(), leading to a use-after-free of ds->dst and
> > dsa_port structures.
> > 
> > In mxl862xx_remove(), dsa_unregister_switch() is called before the
> > asynchronous crc_err_work is cancelled via mxl862xx_host_shutdown():
> > 
> > drivers/net/dsa/mxl862xx/mxl862xx.c:mxl862xx_remove() {
> > 	...
> > 	dsa_unregister_switch(ds);
> > 
> > 	mxl862xx_host_shutdown(priv);
> > 	...
> > }
> > 
> > dsa_unregister_switch() tears down the DSA tree, frees all dsa_port
> > objects, and drops the reference to ds->dst.
> > 
> > If mxl862xx_crc_err_work_fn executes concurrently or after
> > dsa_unregister_switch() has returned, it traverses already freed
> > dsa_port entries:
> > 
> > drivers/net/dsa/mxl862xx/mxl862xx-host.c:mxl862xx_crc_err_work_fn() {
> > 	...
> > 	dsa_switch_for_each_cpu_port(dp, priv->ds)
> > 		dev_close(dp->conduit);
> > 	...
> > }
> > 
> > Could this order in mxl862xx_remove() result in a use-after-free, and
> > should mxl862xx_host_shutdown() be called before dsa_unregister_switch()?
> 
> To really address this a guard in mxl862xx_host_shutdown() will be
> needed. I'd rather do this in a separate Fixes:-patch targetting 'net'
> rather than in this series targetting 'net-next', right?

Yes, that sounds like a good approach to me.