Re: [net-next] r8152: Add 2500baseT EEE status/configuration support

[Birger Koblitz]

Hi Simon,

On 24/02/2026 6:02 pm, Simon Horman wrote:
> This is an AI-generated review of your patch. The human sending this
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>
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> ---
> r8152: Add 2500baseT EEE status/configuration support
>
> The r8152 driver supports the RTL8156, which is a 2.5Gbit Ethernet
> controller for USB 3.0, for which support is added for configuring and
> displaying the EEE advertisement status for 2.5GBit connections. The
> patch also corrects the determination of whether EEE is active to include
> the 2.5GBit connection status and make the determination dependent not on
> the desired speed configuration (tp->speed), but on the actual speed used
> by the controller.
>
> > diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c
> > index 8d36162f36df..a831acd385cd 100644
> > --- a/drivers/net/usb/r8152.c
> > +++ b/drivers/net/usb/r8152.c
>
> [ ... ]
>
> > @@ -8924,6 +8926,7 @@ static int r8152_get_eee(struct r8152 *tp, struct ethtool_keee *eee)
> >   {
> >   	__ETHTOOL_DECLARE_LINK_MODE_MASK(common);
> >   	u16 val;
> > +	u16 speed = rtl8152_get_speed(tp);
>
> Simon says: please declare local variables in reverse xmas tree order -
>              longest line to shortest.
Will fix in v2.

> Does this code read uninitialized memory? The 'common' bitmap is declared
> via __ETHTOOL_DECLARE_LINK_MODE_MASK(common), which expands to
> DECLARE_BITMAP -- an uninitialized stack array:
I will fix this in v2 by initializing common to an empty bitmask.

> [Simon says: I note that Daniel Golle flagged this issue already]
This was forgotten in the edited patch and will be part of v2.

> The same uninitialized memory issue exists here in r8153_get_eee. The
> 'common' bitmap declared via __ETHTOOL_DECLARE_LINK_MODE_MASK is never
> zeroed before individual speed bits are conditionally set with
> linkmode_set_bit(). Then linkmode_and() reads the uninitialized garbage
> bits.
>
> This function affects RTL_VER_03 through RTL_VER_15, which is the majority
> of supported devices.
I will fix this in v2.

Birger