[PATCH ath-next 1/4] wifi: ath12k: signal regd update completion when reg event is dropped

[Baochen Qiang]

During driver bring-up, ath12k_mac_hw_register() reinitializes
ar->regd_update_completed and sends a set current country command to
firmware. It then relies on the regulatory event from firmware to signal
that completion via ath12k_reg_chan_list_event().

However, when the country being set is identical to the one already
applied at boot time, ath12k_reg_validate_reg_info() returns
ATH12K_REG_STATUS_DROP through the "Avoid multiple overwrites to default
regd" path. In that case ath12k_reg_chan_list_event() jumps to mem_free
before assigning pdev_idx, so pdev_idx stays at its initial value of 255,
'ar' remains NULL and complete_all() is never called.

As a result the reinitialized completion is left unsignalled and the next
ath12k_regd_update() waits the full timeout, printing:

  Timeout while waiting for regulatory update

Fix this by assigning pdev_idx from the event's phy_id right after it is
extracted, before validation, so that the drop and fallback paths still
reach complete_all(). Change the guard at the end to check the index
against ab->num_radios so that an out-of-range phy_id does not lead to an
invalid pdevs[] access.

Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c7-00108-QCAHMTSWPL_V1.0_V2.0_SILICONZ_UPSTREAM-3

Fixes: 906619a00967 ("wifi: ath12k: handle regulatory hints during mac registration")
Signed-off-by: Baochen Qiang <baochen.qiang at oss.qualcomm.com>
---
 drivers/net/wireless/ath/ath12k/wmi.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/ath/ath12k/wmi.c b/drivers/net/wireless/ath/ath12k/wmi.c
index 2b707ffc1a20..e9ec56a0e8db 100644
--- a/drivers/net/wireless/ath/ath12k/wmi.c
+++ b/drivers/net/wireless/ath/ath12k/wmi.c
@@ -6964,6 +6964,14 @@ static int ath12k_reg_chan_list_event(struct ath12k_base *ab, struct sk_buff *sk
 		goto mem_free;
 	}
 
+	/*
+	 * Set the valid pdev_idx before validating so that, even when the
+	 * event is dropped or falls back, the completion the caller in
+	 * ath12k_mac_hw_register() may be waiting on is still signalled at
+	 * the end and it does not time out.
+	 */
+	pdev_idx = reg_info->phy_id;
+
 	ret = ath12k_reg_validate_reg_info(ab, reg_info);
 	if (ret == ATH12K_REG_STATUS_FALLBACK) {
 		ath12k_warn(ab, "failed to validate reg info %d\n", ret);
@@ -6980,7 +6988,6 @@ static int ath12k_reg_chan_list_event(struct ath12k_base *ab, struct sk_buff *sk
 	}
 
 	/* free old reg_info if it exist */
-	pdev_idx = reg_info->phy_id;
 	if (ab->reg_info[pdev_idx]) {
 		ath12k_reg_reset_reg_info(ab->reg_info[pdev_idx]);
 		kfree(ab->reg_info[pdev_idx]);
@@ -7019,7 +7026,7 @@ static int ath12k_reg_chan_list_event(struct ath12k_base *ab, struct sk_buff *sk
 
 out:
 	/* In some error cases, even a valid pdev_idx might not be available */
-	if (pdev_idx != 255)
+	if (pdev_idx < ab->num_radios)
 		ar = ab->pdevs[pdev_idx].ar;
 
 	/* During the boot-time update, 'ar' might not be allocated,

-- 
2.25.1