[PATCH net-next] net: stmmac: Call xpcs_config_eee_mult_fact() only when xpcs is present

[Russell King (Oracle)]

On Fri, Mar 21, 2025 at 11:35:01AM +0100, Maxime Chevallier wrote:
> Some dwmac variants such as dwmac_socfpga don't use xpcs but lynx_pcs.
> 
> Don't call xpcs_config_eee_mult_fact() in this case, as this causes a
> crash at init :
> 
>  Unable to handle kernel NULL pointer dereference at virtual address 00000039 when write
> 
>  [...]
> 
>  Call trace:
>   xpcs_config_eee_mult_fact from stmmac_pcs_setup+0x40/0x10c
>   stmmac_pcs_setup from stmmac_dvr_probe+0xc0c/0x1244
>   stmmac_dvr_probe from socfpga_dwmac_probe+0x130/0x1bc
>   socfpga_dwmac_probe from platform_probe+0x5c/0xb0
> 
> Fixes: 060fb27060e8 ("net: stmmac: call xpcs_config_eee_mult_fact()")
> Signed-off-by: Maxime Chevallier <maxime.chevallier at bootlin.com>

Yes, I had noticed that but haven't had time to patch it, so thanks for
submitting the patch. However, I think the code structure could be
better in this function. Let's get the bug fixed, so:

Reviewed-by: Russell King (Oracle) <rmk+kernel at armlinux.org.uk>

Thanks!

-- 
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