Re: [PATCH v2 net 3/4] ixgbe: Fix passing 0 to ERR_PTR in ixgbe_run_xdp()

[Yue Haibing]

On 2024/10/18 20:22, Maciej Fijalkowski wrote:
> On Fri, Oct 18, 2024 at 10:37:33AM +0800, Yue Haibing wrote:
>> ixgbe_run_xdp() converts customed xdp action to a negative error code
>> with the sk_buff pointer type which be checked with IS_ERR in
>> ixgbe_clean_rx_irq(). Remove this error pointer handing instead use
>> plain int return value.
>>
>> Fixes: 924708081629 ("ixgbe: add XDP support for pass and drop actions")
>> Signed-off-by: Yue Haibing <yuehaibing@xxxxxxxxxx>
>> ---
>>  drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 23 ++++++++-----------
>>  1 file changed, 9 insertions(+), 14 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
>> index 8b8404d8c946..78bf97ab0524 100644
>> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
>> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
>> @@ -1908,10 +1908,6 @@ bool ixgbe_cleanup_headers(struct ixgbe_ring *rx_ring,
>>  {
>>  	struct net_device *netdev = rx_ring->netdev;
>>  
>> -	/* XDP packets use error pointer so abort at this point */
>> -	if (IS_ERR(skb))
>> -		return true;
>> -
>>  	/* Verify netdev is present, and that packet does not have any
>>  	 * errors that would be unacceptable to the netdev.
>>  	 */
>> @@ -2219,9 +2215,9 @@ static struct sk_buff *ixgbe_build_skb(struct ixgbe_ring *rx_ring,
>>  	return skb;
>>  }
>>  
>> -static struct sk_buff *ixgbe_run_xdp(struct ixgbe_adapter *adapter,
>> -				     struct ixgbe_ring *rx_ring,
>> -				     struct xdp_buff *xdp)
>> +static int ixgbe_run_xdp(struct ixgbe_adapter *adapter,
>> +			 struct ixgbe_ring *rx_ring,
>> +			 struct xdp_buff *xdp)
> 
> please align args. checkpatch didn't yell at you?

These have aligned in my patch and checkpatch passed.

yuehaibing@localhost:~/code/net$ ./scripts/checkpatch.pl 0003-ixgbe-Fix-passing-0-to-ERR_PTR-in-ixgbe_run_xdp.patch
total: 0 errors, 0 warnings, 0 checks, 67 lines checked

0003-ixgbe-Fix-passing-0-to-ERR_PTR-in-ixgbe_run_xdp.patch has no obvious style problems and is ready for submission.

> 
>>  {
>>  	int err, result = IXGBE_XDP_PASS;
>>  	struct bpf_prog *xdp_prog;
>> @@ -2271,7 +2267,7 @@ static struct sk_buff *ixgbe_run_xdp(struct ixgbe_adapter *adapter,
>>  		break;
>>  	}
>>  xdp_out:
>> -	return ERR_PTR(-result);
>> +	return result;
>>  }
>>  
>>  static unsigned int ixgbe_rx_frame_truesize(struct ixgbe_ring *rx_ring,
>> @@ -2329,6 +2325,7 @@ static int ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector,
>>  	unsigned int offset = rx_ring->rx_offset;
>>  	unsigned int xdp_xmit = 0;
>>  	struct xdp_buff xdp;
>> +	int xdp_res;
>>  
>>  	/* Frame size depend on rx_ring setup when PAGE_SIZE=4K */
>>  #if (PAGE_SIZE < 8192)
>> @@ -2374,12 +2371,10 @@ static int ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector,
>>  			/* At larger PAGE_SIZE, frame_sz depend on len size */
>>  			xdp.frame_sz = ixgbe_rx_frame_truesize(rx_ring, size);
>>  #endif
>> -			skb = ixgbe_run_xdp(adapter, rx_ring, &xdp);
>> +			xdp_res = ixgbe_run_xdp(adapter, rx_ring, &xdp);
>>  		}
>>  
>> -		if (IS_ERR(skb)) {
>> -			unsigned int xdp_res = -PTR_ERR(skb);
>> -
>> +		if (xdp_res) {
>>  			if (xdp_res & (IXGBE_XDP_TX | IXGBE_XDP_REDIR)) {
>>  				xdp_xmit |= xdp_res;
>>  				ixgbe_rx_buffer_flip(rx_ring, rx_buffer, size);
>> @@ -2399,7 +2394,7 @@ static int ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector,
>>  		}
>>  
>>  		/* exit if we failed to retrieve a buffer */
>> -		if (!skb) {
>> +		if (!xdp_res && !skb) {
>>  			rx_ring->rx_stats.alloc_rx_buff_failed++;
>>  			rx_buffer->pagecnt_bias++;
>>  			break;
>> @@ -2413,7 +2408,7 @@ static int ixgbe_clean_rx_irq(struct ixgbe_q_vector *q_vector,
>>  			continue;
>>  
>>  		/* verify the packet layout is correct */
>> -		if (ixgbe_cleanup_headers(rx_ring, rx_desc, skb))
>> +		if (xdp_res || ixgbe_cleanup_headers(rx_ring, rx_desc, skb))
>>  			continue;
>>  
>>  		/* probably a little skewed due to removing CRC */
>> -- 
>> 2.34.1
>>
> 
> 
> .