linux-kernel - [PATCH ath-next 1/3] wifi: ath11k: downgrade log level for CE buffer enqueue failure

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20250815-ath-dont-warn-on-ce-enqueue-fail-v1-1-f955ddc3ba7a@oss.qualcomm.com>
Date: Fri, 15 Aug 2025 09:44:56 +0800
From: Baochen Qiang <baochen.qiang@....qualcomm.com>
To: Jeff Johnson <jjohnson@...nel.org>, Kalle Valo <kvalo@...nel.org>,
        Carl Huang <quic_cjhuang@...cinc.com>,
        Karthikeyan Periyasamy <quic_periyasa@...cinc.com>,
        P Praneesh <quic_ppranees@...cinc.com>,
        Sriram R <quic_srirrama@...cinc.com>
Cc: linux-wireless@...r.kernel.org, ath11k@...ts.infradead.org,
        linux-kernel@...r.kernel.org,
        Jeff Johnson <jeff.johnson@....qualcomm.com>,
        Balamurugan Selvarajan <quic_bselvara@...cinc.com>,
        Ramya Gnanasekar <quic_rgnanase@...cinc.com>,
        ath12k@...ts.infradead.org,
        Baochen Qiang <baochen.qiang@....qualcomm.com>
Subject: [PATCH ath-next 1/3] wifi: ath11k: downgrade log level for CE
 buffer enqueue failure

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 <baochen.qiang@....qualcomm.com>
---
 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