wifi: ath12k: cancel scan only on active scan vdev

Cancel the scheduled scan request only on the vdev that has an active
scan running. Currently, ahvif->links_map is used to obtain the links,
but this includes links for which no scan is scheduled. In failure cases
where the scan fails due to an invalid channel definition, other links
which are not yet brought up (vdev not created) may also be accessed,
leading to the following trace:

Unable to handle kernel paging request at virtual address 0000000000004c8c
pc : _raw_spin_lock_bh+0x1c/0x54
lr : ath12k_scan_abort+0x20/0xc8 [ath12k]

Call trace:
 _raw_spin_lock_bh+0x1c/0x54 (P)
 ath12k_mac_op_cancel_hw_scan+0xac/0xc4 [ath12k]
 ieee80211_scan_cancel+0xcc/0x12c [mac80211]
 ieee80211_do_stop+0x6c4/0x7a8 [mac80211]
 ieee80211_stop+0x60/0xd8 [mac80211]

Skip links that are not created or are not the current scan vdev. This
ensures only the scan for the matching links is aborted and avoids
aborting unrelated links during cancellation, thus aligning with how
start/cleanup manage ar->scan.arvif.

Also, remove the redundant arvif->is_started check from
ath12k_mac_op_cancel_hw_scan() that was introduced in commit 3863f01
("wifi: ath12k: symmetrize scan vdev creation and deletion during HW
scan") to avoid deleting the scan interface if the scan is triggered on
the existing AP vdev as this use case is already handled in
ath12k_scan_vdev_clean_work().

Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.4.1-00199-QCAHKSWPL_SILICONZ-1

Fixes: feed05f ("wifi: ath12k: Split scan request for split band device")
Signed-off-by: Manish Dharanenthiran <manish.dharanenthiran@oss.qualcomm.com>
Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Link: https://patch.msgid.link/20260107-scan_vdev-v1-1-b600aedc645a@qti.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>

Author: Manish Dharanenthiran

drivers/net/wireless/ath/ath12k/mac.c

@@ -5495,7 +5495,8 @@ static void ath12k_mac_op_cancel_hw_scan(struct ieee80211_hw *hw,
 
 	for_each_set_bit(link_id, &links_map, ATH12K_NUM_MAX_LINKS) {
 		arvif = wiphy_dereference(hw->wiphy, ahvif->link[link_id]);
-		if (!arvif || arvif->is_started)
+		if (!arvif || !arvif->is_created ||
+		    arvif->ar->scan.arvif != arvif)
 			continue;
 
 		ar = arvif->ar;