Subject: Re: [PATCH net v2] net/mana: Fix auxiliary device double-delete race

From: Jakub Kicinski <[email-masked]>
Date: Wed, 18 Mar 2026 17:53:44 -0700

On Tue, 17 Mar 2026 07:39:43 -0700 Konstantin Taranov wrote:
> Make remove_adev() safe to call concurrently from the service reset
> and PCI eject paths by using xchg() to atomically claim the adev
> pointer. This prevents double auxiliary_device_delete/uninit when
> hv_eject_device_work races with the service reset workqueue.

Really seems like you should add proper locking to these paths
instead. Are the accesses to is_suspended, rdma_teardown etc
really safe as is?

> diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c
> index 9017e806e..9ae5f01d8 100644
> --- a/drivers/net/ethernet/microsoft/mana/mana_en.c
> +++ b/drivers/net/ethernet/microsoft/mana/mana_en.c
> @@ -3410,14 +3410,18 @@ static void adev_release(struct device *dev)
>  
>  static void remove_adev(struct gdma_dev *gd)
>  {
> -	struct auxiliary_device *adev = gd->adev;
> -	int id = adev->id;
> +	struct auxiliary_device *adev = xchg(&gd->adev, NULL);

nit: avoid falling functions with side effects as variable init

> +	int id;
> +
> +	if (!adev)
> +		return;