RE: [Intel-wired-lan] [PATCH iwl-next v2] libie: log more info when virtchnl fails

[Loktionov, Aleksandr]

> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@xxxxxxxxxx> On Behalf
> Of Li Li via Intel-wired-lan
> Sent: Saturday, April 25, 2026 3:49 AM
> To: Nguyen, Anthony L <anthony.l.nguyen@xxxxxxxxx>; Kitszel,
> Przemyslaw <przemyslaw.kitszel@xxxxxxxxx>; David S. Miller
> <davem@xxxxxxxxxxxxx>; Jakub Kicinski <kuba@xxxxxxxxxx>; Eric Dumazet
> <edumazet@xxxxxxxxxx>; intel-wired-lan@xxxxxxxxxxxxxxxx
> Cc: netdev@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; David
> Decotigny <decot@xxxxxxxxxx>; Singhai, Anjali
> <anjali.singhai@xxxxxxxxx>; Samudrala, Sridhar
> <sridhar.samudrala@xxxxxxxxx>; Brian Vazquez <brianvv@xxxxxxxxxx>; Li
> Li <boolli@xxxxxxxxxx>; Tantilov, Emil S <emil.s.tantilov@xxxxxxxxx>
> Subject: [Intel-wired-lan] [PATCH iwl-next v2] libie: log more info
> when virtchnl fails
> 
> Virtchnl failures can be hard to debug without logs. Logging the
> details of virtchnl transactions can be useful for debugging virtchnl-
> related issues.
> 
> Tested: Built and booted on a test machine.
> 
> Signed-off-by: Li Li <boolli@xxxxxxxxxx>
> ---
> v2:
>  - Use dev_warn_ratelimited instead of dev_notice_ratelimited based on
>    reviewer feedback.
> 
>  drivers/net/ethernet/intel/libie/controlq.c | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/drivers/net/ethernet/intel/libie/controlq.c
> b/drivers/net/ethernet/intel/libie/controlq.c
> index ebc05355e39d..bf200fea1e12 100644
> --- a/drivers/net/ethernet/intel/libie/controlq.c
> +++ b/drivers/net/ethernet/intel/libie/controlq.c
> @@ -762,6 +762,16 @@ libie_ctlq_xn_process_recv(struct
> libie_ctlq_xn_recv_params *params,
>  	status = ctlq_msg->chnl_retval ? -EFAULT : 0;
> 
>  	xn = &xnm->ring[xn_index];
> +
> +	if (ctlq_msg->chnl_retval) {
> +		dev_err_ratelimited(
> +			params->ctlq->dev,
> +			"Non-zero virtchnl ret val (msg op: %u, ret val:
> %u, msg_cookie: %u, data_len: %u); xn op: %u, id: %u, cookie: %u\n",
> +			ctlq_msg->chnl_opcode, ctlq_msg->chnl_retval,
> +			msg_cookie, ctlq_msg->data_len, xn-
> >virtchnl_opcode,
> +			xn->index, xn->cookie);
Dangerous! You add xn logging before it's fields validation.


> +	}
> +
>  	if (ctlq_msg->chnl_opcode != xn->virtchnl_opcode ||
>  	    msg_cookie != xn->cookie)
>  		return false;
> @@ -1011,6 +1021,11 @@ int libie_ctlq_xn_send(struct
> libie_ctlq_xn_send_params *params)
>  		params->recv_mem = xn->recv_mem;
>  		break;
>  	default:
> +		dev_warn_ratelimited(
> +			params->ctlq->dev,
> +			"Transaction failed (op %u, xn state: %d, id: %u,
> cookie: %u, size: %zu)\n",
> +			params->chnl_opcode, xn->state, xn->index, xn-
> >cookie,
> +			xn->recv_mem.iov_len);
>  		ret = -EBADMSG;
>  		break;
>  	}
> --
> 2.54.0.rc2.544.gc7ae2d5bb8-goog