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Date: Wed, 23 Jul 2025 15:16:22 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jason Wang <jasowang@redhat.com>, Stephen Hemminger
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Subject: Re: [PATCH RESEND] netvsc: transfer lower device max tso size
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On Wed, 23 Jul 2025 20:18:03 +0000 Haiyang Zhang wrote:
> > > Btw, if I understand this correctly. This is for future development so
> > > it's not a blocker for this patch?  
> >
> > Not a blocker, I'm just giving an example of the netvsc auto-weirdness
> > being a source of tech debt and bugs. Commit d7501e076d859d is another
> > recent one off the top of my head. IIUC systemd-networkd is broadly
> > deployed now. It'd be great if there was some migration plan for moving
> > this sort of VM auto-bonding to user space (with the use of the common
> > bonding driver, not each hypervisor rolling its own).  
> 
> Actually, we had used the common bonding driver 9 years ago. But it's
> replaced by this kernel/netvsc based "transparent" bonding mode. See
> the patches listed below.
> 
> The user mode bonding scripts were unstable, and difficult to deliver
> & update for various distros. So Stephen developed the new "transparent"
> bonding mode, which greatly improves the situation.

I specifically highlighted systemd-networkd as the change in the user
space landscape.