netdev - Re: [PATCH iwl-next] ice: remove null checks before devm

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Date: Tue, 30 May 2023 20:10:58 +0200
From: Simon Horman <simon.horman@...igine.com>
To: Przemek Kitszel <przemyslaw.kitszel@...el.com>
Cc: intel-wired-lan-bounces@...osl.org,
	Jesse Brandeburg <jesse.brandeburg@...el.com>,
	Tony Nguyen <anthony.l.nguyen@...el.com>,
	Anirudh Venkataramanan <anirudh.venkataramanan@...el.com>,
	Victor Raj <victor.raj@...el.com>,
	Michal Swiatkowski <michal.swiatkowski@...ux.intel.com>,
	Jacob Keller <jacob.e.keller@...el.com>,
	Martyna Szapar-Mudlaw <martyna.szapar-mudlaw@...ux.intel.com>,
	Michal Wilczynski <michal.wilczynski@...el.com>,
	netdev@...r.kernel.org
Subject: Re: [PATCH iwl-next] ice: remove null checks before devm_kfree()
 calls

On Tue, May 30, 2023 at 01:25:49PM +0200, Przemek Kitszel wrote:
> We all know they are redundant.
> 
> Reviewed-by: Michal Swiatkowski <michal.swiatkowski@...ux.intel.com>
> Reviewed-by: Michal Wilczynski <michal.wilczynski@...el.com>
> Signed-off-by: Przemek Kitszel <przemyslaw.kitszel@...el.com>

...

> diff --git a/drivers/net/ethernet/intel/ice/ice_flow.c b/drivers/net/ethernet/intel/ice/ice_flow.c
> index ef103e47a8dc..85cca572c22a 100644
> --- a/drivers/net/ethernet/intel/ice/ice_flow.c
> +++ b/drivers/net/ethernet/intel/ice/ice_flow.c
> @@ -1303,23 +1303,6 @@ ice_flow_find_prof_id(struct ice_hw *hw, enum ice_block blk, u64 prof_id)
>  	return NULL;
>  }
>  
> -/**
> - * ice_dealloc_flow_entry - Deallocate flow entry memory
> - * @hw: pointer to the HW struct
> - * @entry: flow entry to be removed
> - */
> -static void
> -ice_dealloc_flow_entry(struct ice_hw *hw, struct ice_flow_entry *entry)
> -{
> -	if (!entry)
> -		return;
> -
> -	if (entry->entry)
> -		devm_kfree(ice_hw_to_dev(hw), entry->entry);
> -
> -	devm_kfree(ice_hw_to_dev(hw), entry);
> -}
> -
>  /**
>   * ice_flow_rem_entry_sync - Remove a flow entry
>   * @hw: pointer to the HW struct
> @@ -1335,7 +1318,8 @@ ice_flow_rem_entry_sync(struct ice_hw *hw, enum ice_block __always_unused blk,
>  
>  	list_del(&entry->l_entry);
>  
> -	ice_dealloc_flow_entry(hw, entry);
> +	devm_kfree(ice_hw_to_dev(hw), entry->entry);

Hi Przemek,

Previously entry was not dereferenced if it was NULL.
Now it is. Can that occur?

> +	devm_kfree(ice_hw_to_dev(hw), entry);
>  
>  	return 0;
>  }

...