Re: [PATCH net-next v2 06/11] net: protect NAPI enablement with netdev_lock()

On Tue, 21 Jan 2025 11:32:24 +0300
Dan Carpenter [off-list ref] wrote:

On Tue, Jan 14, 2025 at 07:53:14PM -0800, Jakub Kicinski wrote:

quoted

Wrap napi_enable() / napi_disable() with netdev_lock().
Provide the "already locked" flavor of the API.

iavf needs the usual adjustment. A number of drivers call
napi_enable() under a spin lock, so they have to be modified
to take netdev_lock() first, then spin lock then call
napi_enable_locked().  

You missed some.

drivers/net/ethernet/broadcom/tg3.c:7427 tg3_napi_enable() warn: sleeping in atomic context
drivers/net/ethernet/nvidia/forcedeth.c:5597 nv_open() warn: sleeping in atomic context

...

Looks like the whole patch is very fragile.
You really need to keep the existing function names having their existing semantics.
Add a new function, change all the code, then delete the old function.

It also looks as though drivers will end up holding netdev_lock() for long
periods just so they can do a napi_enable() much later on.

	David