On 11/26/24 4:57 AM, James Prestwood wrote:
Hi Remi,
On 11/22/24 8:48 AM, Remi Pommarel wrote:
It has been reported [0] that a 3-4 seconds (actually up to 5 sec) of
radio silence could be observed followed by the error below on ath10k
devices:
ath10k_pci 0000:04:00.0: failed to flush transmit queue (skip 0
ar-state 1): 0
This is due to how the TX queues are flushed in ath10k. When a STA is
removed, mac80211 need to flush queues [1], but because ath10k does not
have a lightweight .flush_sta operation, ieee80211_flush_queues() is
called instead effectively blocking the whole queue during the drain
causing this radio silence. Also because ath10k_flush() waits for all
queued to be emptied, not only the flushed ones it could more easily
take up to 5 seconds to finish making the whole situation worst.
The first patch of this series adds a .flush_sta operation to flush only
specific STA traffic avoiding the need to stop whole queues and should
be enough in itself to fix the reported issue.
The second patch of this series is a proposal to improve ath10k_flush so
that it will be less likely to timeout waiting for non related queues to
drain.
The abose kernel warning could still be observed (e.g. flushing a dead
STA) but should be now harmless.
[0]:
https://lore.kernel.org/all/CA+Xfe4FjUmzM5mvPxGbpJsF3SvSdE5_wgxvgFJ0bsdrKODVXCQ@xxxxxxxxxxxxxx/
[1]: commit 0b75a1b1e42e ("wifi: mac80211: flush queues on STA removal")
I saw in the original report that it indicated it was only for AP mode
but after seeing this and checking some of our clients I saw that this
is also happening in station mode too. I only have clients on 6.2 and
6.8. I can confirm its not occurring on 6.2, but is on 6.8. I also
tried your set of patches but did not notice any behavior difference
with or without them. When it happens, its always just after a roam
scan, ~4 seconds go by and we get the failure followed by a
"Connection to AP <mac> lost". Oddly the MAC address is all zeros.
Nov 25 09:09:50 iwd[16256]: src/station.c:station_start_roam() Using
cached neighbor report for roam
Nov 25 09:09:54 kernel: ath10k_pci 0000:02:00.0: failed to flush
transmit queue (skip 0 ar-state 1): 0
Nov 25 09:09:54 iwd[16256]: src/netdev.c:netdev_mlme_notify() MLME
notification Del Station(20)
Nov 25 09:09:54 iwd[16256]: src/netdev.c:netdev_link_notify() event 16
on ifindex 7
Nov 25 09:09:54 iwd[16256]: src/netdev.c:netdev_mlme_notify() MLME
notification Deauthenticate(39)
Nov 25 09:09:54 iwd[16256]: src/netdev.c:netdev_deauthenticate_event()
Nov 25 09:09:54 iwd[16256]: src/netdev.c:netdev_mlme_notify() MLME
notification Disconnect(48)
Nov 25 09:09:54 iwd[16256]: src/netdev.c:netdev_disconnect_event()
Nov 25 09:09:54 iwd[16256]: Received Deauthentication event, reason:
4, from_ap: false
Nov 25 09:09:54 kernel: wlan0: Connection to AP 00:00:00:00:00:00 lost
Other times, the above logs are preceded by this:
Nov 26 00:25:25 kernel: ath10k_pci 0000:02:00.0: failed to flush sta
txq (sta ca:55:b8:7a:91:4b skip 0 ar-state 1): 0
Note, the above logs are with your patches applied. Maybe this is a
separate issue? Or do you think its related?
Forgot to mention, this is on the QCA6174 hw 3.2
firmware ver WLAN.RM.4.4.1-00288- api 6 features wowlan,ignore-otp,mfp
crc32 bf907c7c
Thanks,
James
V3:
- Initialize empty to true to fix smatch error
V2:
- Add Closes tag
- Use atomic instead of spinlock for per sta pending frame counter
- Call ath10k_htt_tx_sta_dec_pending within rcu
- Rename pending_per_queue[] to num_pending_per_queue[]
Remi Pommarel (2):
wifi: ath10k: Implement ieee80211 flush_sta callback
wifi: ath10k: Flush only requested txq in ath10k_flush()
drivers/net/wireless/ath/ath10k/core.h | 2 +
drivers/net/wireless/ath/ath10k/htt.h | 11 +++-
drivers/net/wireless/ath/ath10k/htt_tx.c | 49 +++++++++++++++-
drivers/net/wireless/ath/ath10k/mac.c | 75 ++++++++++++++++++++----
drivers/net/wireless/ath/ath10k/txrx.c | 11 ++--
5 files changed, 127 insertions(+), 21 deletions(-)
