From: Stephan Gerhold stephan.gerhold@linaro.org
[ Upstream commit 0d1fac6d26aff5df21bb4ec980d9b7a11c410b96 ]
When using the Qualcomm X55 modem on the ThinkPad X13s, the kernel log is constantly being filled with errors related to a "sequence number glitch", e.g.:
[ 1903.284538] sequence number glitch prev=16 curr=0 [ 1913.812205] sequence number glitch prev=50 curr=0 [ 1923.698219] sequence number glitch prev=142 curr=0 [ 2029.248276] sequence number glitch prev=1555 curr=0 [ 2046.333059] sequence number glitch prev=70 curr=0 [ 2076.520067] sequence number glitch prev=272 curr=0 [ 2158.704202] sequence number glitch prev=2655 curr=0 [ 2218.530776] sequence number glitch prev=2349 curr=0 [ 2225.579092] sequence number glitch prev=6 curr=0
Internet connectivity is working fine, so this error seems harmless. It looks like modem does not preserve the sequence number when entering low power state; the amount of errors depends on how actively the modem is being used.
A similar issue has also been seen on USB-based MBIM modems [1]. However, in cdc_ncm.c the "sequence number glitch" message is a debug message instead of an error. Apply the same to the mhi_wwan_mbim.c driver to silence these errors when using the modem.
[1]: https://lists.freedesktop.org/archives/libmbim-devel/2016-November/000781.ht...
Signed-off-by: Stephan Gerhold stephan.gerhold@linaro.org Reviewed-by: Loic Poulain loic.poulain@linaro.org Acked-by: Manivannan Sadhasivam manivannan.sadhasivam@linaro.org Link: https://patch.msgid.link/20250212-mhi-wwan-mbim-sequence-glitch-v1-1-5037359... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/wwan/mhi_wwan_mbim.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/wwan/mhi_wwan_mbim.c b/drivers/net/wwan/mhi_wwan_mbim.c index 3f72ae943b294..b1b2870a054ba 100644 --- a/drivers/net/wwan/mhi_wwan_mbim.c +++ b/drivers/net/wwan/mhi_wwan_mbim.c @@ -209,7 +209,7 @@ static int mbim_rx_verify_nth16(struct mhi_mbim_context *mbim, struct sk_buff *s if (mbim->rx_seq + 1 != le16_to_cpu(nth16->wSequence) && (mbim->rx_seq || le16_to_cpu(nth16->wSequence)) && !(mbim->rx_seq == 0xffff && !le16_to_cpu(nth16->wSequence))) { - net_err_ratelimited("sequence number glitch prev=%d curr=%d\n", + net_dbg_ratelimited("sequence number glitch prev=%d curr=%d\n", mbim->rx_seq, le16_to_cpu(nth16->wSequence)); } mbim->rx_seq = le16_to_cpu(nth16->wSequence);