Re: [PATCH v3] e1000e: Increase iteration on polling MDIC ready bit

[Kai-Heng Feng]

> On Sep 25, 2020, at 03:57, Andrew Lunn <andrew@xxxxxxx> wrote:
> 
> On Fri, Sep 25, 2020 at 12:45:42AM +0800, Kai-Heng Feng wrote:
>> We are seeing the following error after S3 resume:
>> [  704.746874] e1000e 0000:00:1f.6 eno1: Setting page 0x6020
>> [  704.844232] e1000e 0000:00:1f.6 eno1: MDI Write did not complete
>> [  704.902817] e1000e 0000:00:1f.6 eno1: Setting page 0x6020
>> [  704.903075] e1000e 0000:00:1f.6 eno1: reading PHY page 769 (or 0x6020 shifted) reg 0x17
>> [  704.903281] e1000e 0000:00:1f.6 eno1: Setting page 0x6020
>> [  704.903486] e1000e 0000:00:1f.6 eno1: writing PHY page 769 (or 0x6020 shifted) reg 0x17
>> [  704.943155] e1000e 0000:00:1f.6 eno1: MDI Error
>> ...
>> [  705.108161] e1000e 0000:00:1f.6 eno1: Hardware Error
>> 
>> As Andrew Lunn pointed out, MDIO has nothing to do with phy, and indeed
>> increase polling iteration can resolve the issue.
>> 
>> The root cause is quite likely Intel ME, since it's a blackbox to the
>> kernel so the only approach we can take is to be patient and wait
>> longer.
> 
> Please could you explain how you see Intel ME being responsible for
> this. I'm not convinced.

Some other occurrences:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d17c7868b2f8e329dcee4ecd2f5d16cfc9b26ac8
https://lore.kernel.org/netdev/20200323191639.48826-1-aaron.ma@xxxxxxxxxxxxx/

Of course we need an ACK from Intel this one is also related to ME.

Kai-Heng

> 
>      Andrew