netdev - Re: [PATCH 2/2] net: sfp: support 25G long-range modules (extended compliance code 0x3)

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <b42b2f5e-917d-4088-99ad-67214bb288ee@solid-run.com>
Date: Wed, 21 Jan 2026 09:44:11 +0000
From: Josua Mayer <josua@...id-run.com>
To: Jakub Kicinski <kuba@...nel.org>
CC: Andrew Lunn <andrew@...n.ch>, Heiner Kallweit <hkallweit1@...il.com>,
	Russell King <linux@...linux.org.uk>, "David S. Miller"
	<davem@...emloft.net>, Eric Dumazet <edumazet@...gle.com>, Paolo Abeni
	<pabeni@...hat.com>, Simon Horman <horms@...nel.org>, Mikhail Anikin
	<mikhail.anikin@...id-run.com>, Rabeeh Khoury <rabeeh@...id-run.com>, Yazan
 Shhady <yazan.shhady@...id-run.com>, "netdev@...r.kernel.org"
	<netdev@...r.kernel.org>, "linux-kernel@...r.kernel.org"
	<linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 2/2] net: sfp: support 25G long-range modules (extended
 compliance code 0x3)

On 19/01/2026 21:30, Jakub Kicinski wrote:
> On Sun, 18 Jan 2026 16:07:38 +0200 Josua Mayer wrote:
>> @@ -247,6 +247,7 @@ static void sfp_module_parse_support(struct sfp_bus *bus,
>>   	case SFF8024_ECC_100GBASE_LR4_25GBASE_LR:
>>   	case SFF8024_ECC_100GBASE_ER4_25GBASE_ER:
>>   		phylink_set(modes, 100000baseLR4_ER4_Full);
>> +		phylink_set(modes, 25000baseLR_Full);
> I _think_ the discussion here concluded that the patch is insufficient
> / DoA? Either way, I wanted to relay that AI code review points out
> we may also want to set __set_bit(PHY_INTERFACE_MODE_25GBASER,
> interfaces) here:
>
> https://netdev-ai.bots.linux.dev/ai-review.html?id=c91c0f54-56d5-4356-89cd-b57cbb289495
>
I concluded the following:

1. there is no confusion with qsfp / 4 serdes lanes

2. 25GBASER is indeed missing, because this case does not fallthrough.

Something open for discussion is whether to handle
SFF8024_ECC_100GBASE_LR4_25GBASE_LR/_ER differently, e.g.:

     case SFF8024_ECC_100GBASE_LR4_25GBASE_LR:
         phylink_set(modes, 25000baseLR_Full);
         fallthrough;
     case SFF8024_ECC_100GBASE_ER4_25GBASE_ER:
         phylink_set(modes, 100000baseLR4_ER4_Full);
         __set_bit(PHY_INTERFACE_MODE_25GBASER, interfaces);
         break;

I.e. should the ER variant support 25000baseLR_Full?