RE: [PATCH net v2] r8152: Use BMSR to detect the link state

From: Hayes Wang

Date: Tue Oct 13 2026 - 06:46:59 EST


Linmao Li <lilinmao@xxxxxxxxxx>
> Sent: Tuesday, October 13, 2026 10:36 AM
[...]
> Hi Andrew,
>
> Thanks. In tests on my RTL8153B, down and up notifications were about
> 3.1 s apart after a quick cable replug, and about 3.4 s apart after ethtool -r. A
> double read should still report down if the link work runs during that interval,
> but I have not verified this directly.
> These results do not cover shorter link interruptions or other chips.
>
> Since this fixes a regression for net and stable, would you accept a) there,
> keeping PLA_PHYSTATUS and reading BMSR once before an off-to-on carrier
> transition, and moving carrier detection to BMSR with per-chip handling as a
> follow-up for net-next, once the chip behaviour is known?
>
> Hayes, to build that list: which ICs notify only on link changes? And on any of
> them, does reading BMSR, which clears the latched link down, trigger another
> notification? The single read depends on that. Birger tested v2 on an RTL8157
> and an RTL8153A without problems, so it would also help to know how the
> RTL8157 notifies.

Some users have complained about the periodic notifications, so we plan to modify the driver accordingly.
RTL8156 and later chips will notify the driver only when the link state changes.
The Windows driver already uses this behavior.
In addition, I don’t believe that clearing the latched link-down status will trigger another notification.


Best Regards,
Hayes