Re: [Intel-wired-lan] [PATCH] igb: cope with large MAX_SKB_FRAGS.

[Jiri Pirko <jiri@resnulli.us>]

Tue, Apr 23, 2024 at 03:54:05PM CEST, vinschen@redhat.com wrote:
>Hi Jiri,
>
>On Apr 23 13:26, Jiri Pirko wrote:
>> Tue, Apr 23, 2024 at 12:24:46PM CEST, vinschen@redhat.com wrote:
>> >From: Paolo Abeni <pabeni@redhat.com>
>> >
>> >Sabrina reports that the igb driver does not cope well with large
>> >MAX_SKB_FRAG values: setting MAX_SKB_FRAG to 45 causes payload
>> >corruption on TX.
>> >
>> >The root cause of the issue is that the driver does not take into
>> >account properly the (possibly large) shared info size when selecting
>> >the ring layout, and will try to fit two packets inside the same 4K
>> >page even when the 1st fraglist will trump over the 2nd head.
>> >
>> >Address the issue forcing the driver to fit a single packet per page,
>> >leaving there enough room to store the (currently) largest possible
>> >skb_shared_info.
>> >
>> >Fixes: 3948b05950fd ("net: introduce a config option to tweak MAX_SKB_FRAG")
>> >Reported-by: Jan Tluka <jtluka@redhat.com>
>> >Reported-by: Jirka Hladky <jhladky@redhat.com>
>> >Reported-by: Sabrina Dubroca <sd@queasysnail.net>
>> >Tested-by: Sabrina Dubroca <sd@queasysnail.net>
>> >Tested-by: Corinna Vinschen <vinschen@redhat.com>
>> >Signed-off-by: Paolo Abeni <pabeni@redhat.com>
>> >---
>> > drivers/net/ethernet/intel/igb/igb_main.c | 1 +
>> 
>> Also, please use get_maintainer.pl script to get cclist.
>
>done and done in v2 (for which I forgot the "in-reply-to" now, d'uh)

In-reply-to is not needed. Send each V to separate thread.

>
>Thanks,
>Corinna
>
>