Re: [PATCH 2/2] hv_netvsc: Use VF's tso_max_size value when data path is VF
From: Stephen Hemminger <stephen@networkplumber.org>
Date: 2025-02-05 05:56:46
Also in:
linux-hyperv, lkml
From: Stephen Hemminger <stephen@networkplumber.org>
Date: 2025-02-05 05:56:46
Also in:
linux-hyperv, lkml
On Tue, 4 Feb 2025 20:21:55 -0800 Shradha Gupta [off-list ref] wrote:
On Azure, increasing VF's TCP segment size to up-to GSO_MAX_SIZE is not possible without allowing the same for netvsc NIC (as the NICs are bonded together). For bonded NICs, the min of the max segment size of the members is propagated in the stack. Therefore, we use netif_set_tso_max_size() to set max segment size to VF's segment size for netvsc too, when the data path is switched over to the VF Tested on azure env with Accelerated Networking enabled and disabled. Signed-off-by: Shradha Gupta <redacted> Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Since datapath can change at anytime (ie hot remove of VF). How does TCP stack react to GSO max size changing underneath it. Is it like a path MTU change where some packets are lost until TCP retries and has to rediscover?