This is a note to let you know that I've just added the patch titled
wifi: ath12k: fix Smatch warnings on ath12k_core_suspend()
to the 6.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
wifi-ath12k-fix-smatch-warnings-on-ath12k_core_suspe.patch
and it can be found in the queue-6.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit cd986b4915850937aa214ab6a03fddbc74484cb5
Author: Baochen Qiang <quic_bqiang@xxxxxxxxxxx>
Date: Mon May 20 14:58:28 2024 +0300
wifi: ath12k: fix Smatch warnings on ath12k_core_suspend()
[ Upstream commit 33370412eced2dc7f81f4324e109d69319cafd82 ]
Smatch is throwing below warning:
Commit 692921ead832 ("wifi: ath12k: flush all packets before
suspend") leads to the following Smatch static checker warning:
drivers/net/wireless/ath/ath12k/core.c:58 ath12k_core_suspend()
warn: sleeping in atomic context
and also gives the reason:
drivers/net/wireless/ath/ath12k/core.c
48 int ret, i;
49
50 if (!ab->hw_params->supports_suspend)
51 return -EOPNOTSUPP;
52
53 rcu_read_lock();
^^^^^^^^^^^^^^^
Disables preemption.
54 for (i = 0; i < ab->num_radios; i++) {
55 ar = ath12k_mac_get_ar_by_pdev_id(ab, i);
56 if (!ar)
57 continue;
--> 58 ret = ath12k_mac_wait_tx_complete(ar);
^^^^^^^
Sleeping in atomic context.
59 if (ret) {
60 ath12k_warn(ab, "failed to wait tx complete: %d\n", ret);
61 rcu_read_unlock();
62 return ret;
63 }
64 }
65 rcu_read_unlock();
But it is weird that no warning on this in run time even with
CONFIG_DEBUG_ATOMIC_SLEEP=y. With some debug it is found that this is
because: when system goes to suspend, ath12k_mac_op_stop() gets called
where then in ath12k_mac_stop() ab->pdevs_active[ar->pdev_idx] is cleared.
This results in ath12k_mac_get_ar_by_pdev_id() always returning a NULL ar,
and thereby ath12k_mac_wait_tx_complete() never gets a chance to run.
Fix it by retrieving ar directly from ab->pdevs[].ar instead of using
ath12k_mac_get_ar_by_pdev_id(). Since ab->pdevs[].ar is set at boot time
and won't get cleared when suspend, ath12k_mac_wait_tx_complete() won't
be skipped. In addition, with ath12k_mac_get_ar_by_pdev_id() removed,
rcu_read_lock()/unlock() are not needed any more, so remove them. This
also fixes the warning above.
Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.0-03427-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1.15378.4
Fixes: 692921ead832 ("wifi: ath12k: flush all packets before suspend")
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Closes: https://lore.kernel.org/ath12k/7a96ca11-80b5-4751-8cfc-fa637f3aa63a@moroto.mountain/
Signed-off-by: Baochen Qiang <quic_bqiang@xxxxxxxxxxx>
Acked-by: Jeff Johnson <quic_jjohnson@xxxxxxxxxxx>
Signed-off-by: Kalle Valo <quic_kvalo@xxxxxxxxxxx>
Link: https://msgid.link/20240511095045.9623-1-quic_bqiang@xxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/wireless/ath/ath12k/core.c b/drivers/net/wireless/ath/ath12k/core.c
index 6663f4e1792de..527cfa3a01ad3 100644
--- a/drivers/net/wireless/ath/ath12k/core.c
+++ b/drivers/net/wireless/ath/ath12k/core.c
@@ -50,19 +50,16 @@ int ath12k_core_suspend(struct ath12k_base *ab)
if (!ab->hw_params->supports_suspend)
return -EOPNOTSUPP;
- rcu_read_lock();
for (i = 0; i < ab->num_radios; i++) {
- ar = ath12k_mac_get_ar_by_pdev_id(ab, i);
+ ar = ab->pdevs[i].ar;
if (!ar)
continue;
ret = ath12k_mac_wait_tx_complete(ar);
if (ret) {
ath12k_warn(ab, "failed to wait tx complete: %d\n", ret);
- rcu_read_unlock();
return ret;
}
}
- rcu_read_unlock();
/* PM framework skips suspend_late/resume_early callbacks
* if other devices report errors in their suspend callbacks.
