[PATCH net] net: stmmac: leave the datapath running for normal-size MTU changes

[Jakub Kicinski]

On Wed, 30 Sep 2026 22:39:22 -0600 James Hilliard wrote:
> When both MTUs are at most ETH_DATA_LEN, the receive buffer size and MAC
> receive limit do not change. Update the MTU without restarting the
> datapath.
> 
> This also avoids rebinding a live AF_XDP pool to a temporary RXQ. XDP
> rejects jumbo MTUs, so all supported XDP MTU changes take this path.
> Jumbo transitions remain on the reopen path until the rollback change.
> 
> Fixes: 3470079687448 ("net: ethernet: stmicro: stmmac: permit MTU change with interface up")

Someone marked this as Changes Requested in patchwork, no idea who.

Change seems good, but it's an optimization for net-next, no fixes tag