From: Baochen Qiang <quic_bqiang@quicinc.com>
To: <ath12k@lists.infradead.org>
Cc: <linux-wireless@vger.kernel.org>, <quic_bqiang@quicinc.com>
Subject: [PATCH] wifi: ath12k: fix Smatch warnings on ath12k_core_suspend()
Date: Sat, 11 May 2024 17:50:45 +0800 [thread overview]
Message-ID: <20240511095045.9623-1-quic_bqiang@quicinc.com> (raw)
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@linaro.org>
Closes: https://lore.kernel.org/ath12k/7a96ca11-80b5-4751-8cfc-fa637f3aa63a@moroto.mountain/
Signed-off-by: Baochen Qiang <quic_bqiang@quicinc.com>
---
drivers/net/wireless/ath/ath12k/core.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)
diff --git a/drivers/net/wireless/ath/ath12k/core.c b/drivers/net/wireless/ath/ath12k/core.c
index 9482d5db71e7..e7f628e935e4 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.
base-commit: 1025c616ee13372f3803b158abb1d87ef368ae3d
--
2.25.1
next reply other threads:[~2024-05-11 9:51 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-05-11 9:50 Baochen Qiang [this message]
2024-05-14 14:12 ` [PATCH] wifi: ath12k: fix Smatch warnings on ath12k_core_suspend() Jeff Johnson
2024-05-21 8:05 ` Kalle Valo
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