VER-847: ath12k: peer lookup failure during STA stats retrieval (tentative fix)#75
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adrian-nicolau merged 2 commits intotg-v6.18-ath12k-nextfrom Mar 12, 2026
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March 10, 2026 13:16
To get firmware statistics, currently ar->pdev->pdev_id is passed as an
argument to ath12k_mac_get_fw_stats() in ath12k_mac_op_sta_statistics().
For single pdev device like WCN7850, its value is 0 which represents the
SoC pdev id. As a result, WCN7850 firmware sends the same reply to host
twice, which further results in memory leak:
unreferenced object 0xffff88812e286000 (size 192):
comm "softirq", pid 0, jiffies 4294981997
hex dump (first 32 bytes):
10 a5 40 11 81 88 ff ff 10 a5 40 11 81 88 ff ff ..@.......@.....
00 00 00 00 00 00 00 00 80 ff ff ff 33 05 00 00 ............3...
backtrace (crc cecc8c82):
__kmalloc_cache_noprof
ath12k_wmi_tlv_fw_stats_parse
ath12k_wmi_tlv_iter
ath12k_wmi_op_rx
ath12k_htc_rx_completion_handler
ath12k_ce_per_engine_service
ath12k_pci_ce_workqueue
process_one_work
bh_worker
tasklet_action
handle_softirqs
Detailed explanation is:
1. ath12k_mac_get_fw_stats() called in ath12k_mac_op_sta_statistics() to
get vdev statistics, making the caller thread wait.
2. firmware sends the first reply, ath12k_wmi_tlv_fw_stats_data_parse()
allocates buffers to cache necessary information. Following that, in
ath12k_wmi_fw_stats_process() if events of all started vdev haved been
received, is_end flag is set hence the waiting thread gets waken up by
the ar->fw_stats_done/->fw_stats_complete signals.
3. ath12k_mac_get_fw_stats() wakes up and returns successfully.
ath12k_mac_op_sta_statistics() saves required parameters and calls
ath12k_fw_stats_reset() to free buffers allocated earlier.
4. firmware sends the second reply. As usual, buffers are allocated and
attached to the ar->fw_stats.vdevs list. Note this time there is no
thread waiting, therefore no chance to free those buffers.
5. ath12k module gets unloaded. If there has been no more firmware
statistics request made since step 4, or if the request fails (see
the example in the following patch), there is no chance to call
ath12k_fw_stats_reset(). Consequently those buffers leak.
Actually for single pdev device, using SoC pdev id in
ath12k_mac_op_sta_statistics() is wrong, because the purpose is to get
statistics of a specific station, which is mapped to a specific pdev. That
said, the id of actual individual pdev should be fetched and used instead.
The helper ath12k_mac_get_target_pdev_id() serves for this purpose, hence
use it to fix this issue. Note it also works for other devices as well due
to the single_pdev_only check inside.
The same applies to ath12k_mac_op_get_txpower() and
ath12k_mac_op_link_sta_statistics() as well.
Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c5-00302-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1.115823.3
Fixes: 79e7b04 ("wifi: ath12k: report station mode signal strength")
Fixes: e92c658 ("wifi: ath12k: add get_txpower mac ops")
Fixes: ebebe66 ("wifi: ath12k: fill link station statistics for MLO")
Signed-off-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Link: https://patch.msgid.link/20260129-ath12k-fw-stats-fixes-v1-1-55d66064f4d5@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
In ath12k_wmi_tlv_fw_stats_data_parse() and ath12k_wmi_tlv_rssi_chain_parse(), the driver uses ieee80211_find_sta_by_ifaddr() to look up the station associated with the incoming firmware statistics. This works under normal conditions but fails during AP disconnection, resulting in log messages like: wlan0: deauthenticating from xxxxxx by local choice (Reason: 3=DEAUTH_LEAVING) wlan0: moving STA xxxxxx to state 3 wlan0: moving STA xxxxxx to state 2 wlan0: moving STA xxxxxx to state 1 ath12k_pci 0000:02:00.0: not found station bssid xxxxxx for vdev stat ath12k_pci 0000:02:00.0: not found station of bssid xxxxxx for rssi chain ath12k_pci 0000:02:00.0: failed to pull fw stats: -71 ath12k_pci 0000:02:00.0: time out while waiting for get fw stats wlan0: Removed STA xxxxxx wlan0: Destroyed STA xxxxxx The failure happens because the station has already been removed from ieee80211_local::sta_hash by the time firmware statistics are requested through drv_sta_statistics(). Switch the lookup to ath12k_link_sta_find_by_addr(), which searches the driver's link station hash table that still has the station recorded at that time. This also implicitly fixes another issue: the current code always uses deflink regardless of which link the statistics belong to, which is incorrect in MLO scenarios. The new helper returns the correct link station. Additionally, raise the log level on lookup failures. With the updated helper, such failures should no longer occur under normal conditions. Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c5-00302-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1.115823.3 Fixes: 79e7b04 ("wifi: ath12k: report station mode signal strength") Fixes: 6af5bc3 ("wifi: ath12k: report station mode per-chain signal strength") Signed-off-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com> Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com> Link: https://patch.msgid.link/20260129-ath12k-fw-stats-fixes-v1-2-55d66064f4d5@oss.qualcomm.com Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
michaeln-ceragon
approved these changes
Mar 12, 2026
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This PR cherry-picks the latest advancements of upstream ath12k driver. They address issues with ath12k station statistics requests (trace shows problem with
ath12k_mac_op_sta_statistics), so they may help resolve the issue we are seeing.However, we've seen the
failed to find the peer with peer_iderror in the past, caused by torvalds/linux@981050b and also reported here https://bugzilla.kernel.org/show_bug.cgi?id=221039 . We reverted it in the past, and if the issue still reproduces after this PR we might need to revert it again.Qualcomm's driver changes the log level of this error to debug in https://git.codelinaro.org/clo/qsdk/oss/src/mac80211/wlan-open/-/commit/c8f276e7615d3156e07e1ed217ca96a2484ada09