There are two rings involved in the Copy Engine (CE) receive path handling, the CE status (STS) ring and the CE destination (DST) ring. Each time CE hardware needs to send an event (e.g. WMI event) to host, CE hardware finds a buffer (to which the tail pointer (TP) points) in DST ring and fills it with payload, then hardware fills meta data in STS ring and fires interrupt to host. Please note the TP of DST ring is expected to be advanced by CE hardware before interrupting host. While handling the interrupt, host finds that DST ring buffers are used hence increases rx_buf_needed to record the number of buffers to be replenished. Note before that, host compares TP and head pointer (HP) of DST ring to see if there is available space. Normally rx_buf_needed simply equals available space. But sometimes CE hardware doesn't (for whatever reason) update TP timely, making the comparison fails, then enqueue is cancelled and a warning is logged: ath11k_pci 0000:02:00.0: failed to enqueue rx buf: -28 However even enqueue fails this time, rx_buf_needed still records the numbers of needed buffers. Later when TP gets updated correctly, the missing buffer will be eventually replenished. And there is no doubt on the late update, it always comes (or lots of such warnings should be seen). Since this won't cause any functional issue, downgrade logging level to avoid misleading. Compile tested only. Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220269 Signed-off-by: Baochen Qiang --- drivers/net/wireless/ath/ath11k/ce.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/ath/ath11k/ce.c b/drivers/net/wireless/ath/ath11k/ce.c index c65fc9fb539ef10ba44f1c1d5571462b40fa098d..a7a163621b21067ba5a4f96131aafdccfbda3d03 100644 --- a/drivers/net/wireless/ath/ath11k/ce.c +++ b/drivers/net/wireless/ath/ath11k/ce.c @@ -354,7 +354,8 @@ static int ath11k_ce_rx_post_pipe(struct ath11k_ce_pipe *pipe) ret = ath11k_ce_rx_buf_enqueue_pipe(pipe, skb, paddr); if (ret) { - ath11k_warn(ab, "failed to enqueue rx buf: %d\n", ret); + ath11k_dbg(ab, ATH11K_DBG_CE, "failed to enqueue rx buf: %d\n", + ret); dma_unmap_single(ab->dev, paddr, skb->len + skb_tailroom(skb), DMA_FROM_DEVICE); -- 2.25.1