RE: [Intel-wired-lan] [PATCH net-next v9 1/7] net: core: Add state tracking for async netdev ops

[Loktionov, Aleksandr]

> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@xxxxxxxxxx> On Behalf
> Of I Viswanath
> Sent: Saturday, March 14, 2026 7:28 PM
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> Subject: [Intel-wired-lan] [PATCH net-next v9 1/7] net: core: Add
> state tracking for async netdev ops
> 
> Async netdev ops are tricky because of the following problems:
> 
> 1) Freeing the context associated with async netdev ops might require
>    waiting for completion of the associated work which might require
> the
>    rtnl lock or the instance lock. However this will deadlock in
>    __dev_close_many as the cleanup is done with those locks already
> held.
> 
> 2) We need a way to enable/disable async netdev ops depending on the
> PM
>    state to allow/prevent hardware access as appropriate.
> 
> We solve these problems by introducing a state variable to track the
> current state of netdev. This can take the following values:
> - ACTIVE (up and normal operation)
> - DOWN (down)
> - INACTIVE (in suspend/shutdown)
> 
> To solve 1, we set the state to down in __dev_close_many. In the
> associated op handler, we check for the current state and return if
> the netdev is down.
> 
> To solve 2, the commit introduces the following functions:
> - netif_enable_async_ops  -> sets state to ACTIVE
> - netif_disable_async_ops -> sets state to INACTIVE and cancels any
> 			     pending work as required.
> 
> The op implementation can use the state information to do the required
> processing.
> 
> Signed-off-by: I Viswanath <viswanathiyyappan@xxxxxxxxx>
> ---
>  include/linux/netdevice.h | 29 ++++++++++++++
>  net/core/dev.c            | 84
> ++++++++++++++++++++++++++++++++++++++-
>  2 files changed, 111 insertions(+), 2 deletions(-)
> 

...

> --
> 2.47.3

Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@xxxxxxxxx>