On Tue, Jan 21, 2025 at 11:15 PM Jakub Kicinski <kuba@xxxxxxxxxx> wrote:
>
> mt76 does a lot of:
>
> local_bh_disable();
> napi_enable(...napi);
> napi_schedule(...napi);
> local_bh_enable();
>
> local_bh_disable() is not a real lock, its most likely taken
> because napi_schedule() requires it. napi_enable() needs
> to take a mutex, so move it from under the BH protection.
>
> Fixes: 413f0271f396 ("net: protect NAPI enablement with netdev_lock()")
> Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> Link: https://lore.kernel.org/dcfd56bc-de32-4b11-9e19-d8bd1543745d@stanley.mountain
> Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Reviewed-by: Eric Dumazet <edumazet@xxxxxxxxxx>
napi_schedule() can run from arbitrary contexts though...
BH protection seems strange to me, but this is orthogonal to your fix.
