> -----Original Message-----
> From: Stanislav Fomichev <[email protected]>
> Sent: Friday, March 20, 2026 2:25 AM
> To: [email protected]
> Cc: [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected];
> [email protected]; [email protected]; Nguyen, Anthony
> L <[email protected]>; Kitszel, Przemyslaw
> <[email protected]>; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected]; Keller,
> Jacob E <[email protected]>; [email protected];
> [email protected]; [email protected]; Loktionov, Aleksandr
> <[email protected]>; [email protected]; linux-
> [email protected]; [email protected]; intel-wired-
> [email protected]; [email protected]; linux-
> [email protected]; [email protected];
> [email protected]
> Subject: [PATCH net-next v3 04/13] net: move promiscuity handling into
> dev_rx_mode_work
> 
> Move unicast promiscuity tracking into dev_rx_mode_work so it runs
> under netdev_ops_lock instead of under the addr_lock spinlock. This is
> required because __dev_set_promiscuity calls dev_change_rx_flags and
> __dev_notify_flags, both of which may need to sleep.
> 
> Change ASSERT_RTNL() to netdev_ops_assert_locked() in
> __dev_set_promiscuity, netif_set_allmulti and __dev_change_flags since
> these are now called from the work queue under the ops lock.
> 
> Reviewed-by: Aleksandr Loktionov <[email protected]>
> Signed-off-by: Stanislav Fomichev <[email protected]>
> ---
>  Documentation/networking/netdevices.rst |  4 ++
>  net/core/dev.c                          | 79 +++++++++++++++++-------
> -
>  2 files changed, 57 insertions(+), 26 deletions(-)
> 
> diff --git a/Documentation/networking/netdevices.rst
> b/Documentation/networking/netdevices.rst
> index dc83d78d3b27..5cdaa1a3dcc8 100644
> --- a/Documentation/networking/netdevices.rst
> +++ b/Documentation/networking/netdevices.rst
> @@ -298,6 +298,10 @@ struct net_device synchronization rules
>       Notes: Sleepable version of ndo_set_rx_mode. Receives snapshots
>       of the unicast and multicast address lists.
> 
> +ndo_change_rx_flags:
> +     Synchronization: rtnl_lock() semaphore. In addition, netdev
> instance
> +     lock if the driver implements queue management or shaper API.
> +
>  ndo_setup_tc:
>       ``TC_SETUP_BLOCK`` and ``TC_SETUP_FT`` are running under NFT
> locks
>       (i.e. no ``rtnl_lock`` and no device instance lock). The rest
> of diff --git a/net/core/dev.c b/net/core/dev.c index
> fedc423306fc..fc5c9b14faa0 100644
> --- a/net/core/dev.c
> +++ b/net/core/dev.c
> @@ -9574,7 +9574,7 @@ static int __dev_set_promiscuity(struct
> net_device *dev, int inc, bool notify)
>       kuid_t uid;
>       kgid_t gid;
> 
> -     ASSERT_RTNL();
> +     netdev_ops_assert_locked(dev);
Can you explain why do you add new hard precondition of ops lock must be held?


> 
>       promiscuity = dev->promiscuity + inc;
>       if (promiscuity == 0) {
> @@ -9610,16 +9610,8 @@ static int __dev_set_promiscuity(struct
> net_device *dev, int inc, bool notify)
> 
>               dev_change_rx_flags(dev, IFF_PROMISC);
>       }

...

>       __hw_addr_init(&uc_snap);
> @@ -9704,16 +9720,29 @@ static void dev_rx_mode_work(struct
> work_struct *work)
>               if (!err)
>                       err = __hw_addr_list_snapshot(&mc_ref, &dev->mc,
>                                                     dev->addr_len);
> -             netif_addr_unlock_bh(dev);
> 
>               if (err) {
>                       netdev_WARN(dev, "failed to sync uc/mc
> addresses\n");
>                       __hw_addr_flush(&uc_snap);
>                       __hw_addr_flush(&uc_ref);
>                       __hw_addr_flush(&mc_snap);
> +                     netif_addr_unlock_bh(dev);
>                       goto out;
>               }
> 
> +             promisc_inc = dev_uc_promisc_update(dev);
> +
> +             netif_addr_unlock_bh(dev);
> +     } else {
> +             netif_addr_lock_bh(dev);
> +             promisc_inc = dev_uc_promisc_update(dev);
> +             netif_addr_unlock_bh(dev);
> +     }
> +
> +     if (promisc_inc)
> +             __dev_set_promiscuity(dev, promisc_inc, false);
But it's being called here without any netdev_lock_ops(dev) ?

> +
> +     if (ops->ndo_set_rx_mode_async) {
>               ops->ndo_set_rx_mode_async(dev, &uc_snap, &mc_snap);
> 
>               netif_addr_lock_bh(dev);
> @@ -9722,6 +9751,10 @@ static void dev_rx_mode_work(struct work_struct
> *work)
>               __hw_addr_list_reconcile(&dev->mc, &mc_snap,
>                                        &mc_ref, dev->addr_len);
>               netif_addr_unlock_bh(dev);
> +     } else if (ops->ndo_set_rx_mode) {
> +             netif_addr_lock_bh(dev);
> +             ops->ndo_set_rx_mode(dev);
> +             netif_addr_unlock_bh(dev);
>       }

...

> --
> 2.53.0


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