Re: net: phy: realtek: regression, kernel null pointer dereference

From: Vicente Bergas
Date: Sat May 11 2019 - 11:07:41 EST

On Saturday, May 11, 2019 4:56:56 PM CEST, Heiner Kallweit wrote:
On 11.05.2019 16:46, Vicente Bergas wrote:
On Friday, May 10, 2019 10:28:06 PM CEST, Heiner Kallweit wrote:
On 10.05.2019 17:05, Vicente Bergas wrote: ...

Hello Heiner,
just tried your patch and indeed the NPE is gone. But still no network...
The MAC <-> PHY link was working before, so, maybe the rgmii delays are not
correctly configured.

That's a question to the author of the original patch. My patch was just
meant to fix the NPE. In which configuration are you using the RTL8211E?
As a standalone PHY (with which MAC/driver?) or is it the integrated PHY
in a member of the RTL8168 family?

It is the one on the Sapphire board, so is connected to the MAC on the
RK3399 SoC. It is on page 8 of the schematics:

Serge: The issue with the NPE gave a hint already that you didn't test your
patch. Was your patch based on an actual issue on some board and did you
test it? We may have to consider reverting the patch.

With this change it is back to working:
--- a/drivers/net/phy/realtek.c
+++ b/drivers/net/phy/realtek.c
@@ -300,7 +300,6 @@
}, {
.name = "RTL8211E Gigabit Ethernet",
- .config_init = &rtl8211e_config_init,
.ack_interrupt = &rtl821x_ack_interrupt,
.config_intr = &rtl8211e_config_intr,
.suspend = genphy_suspend,
That is basically reverting the patch.


Nevertheless your proposed patch looks good to me, just one small change
would be needed and it should be splitted.

The change to phy-core I would consider a fix and it should be fine to
submit it to net (net-next is closed currently).

Adding the warning to the Realtek driver is fine, but this would be ...