On 7/8/2025 4:08 PM, Johannes Berg wrote:
On Tue, 2025-07-01 at 19:43 +0530, Amith A wrote:
+++ b/net/wireless/nl80211.c
@@ -9758,6 +9758,7 @@ static bool cfg80211_off_channel_oper_allowed(struct wireless_dev *wdev,
{
unsigned int link_id;
bool all_ok = true;
+ int radio_idx;
lockdep_assert_wiphy(wdev->wiphy);
@@ -9765,10 +9766,16 @@ static bool cfg80211_off_channel_oper_allowed(struct wireless_dev *wdev,
return false;
if (!cfg80211_beaconing_iface_active(wdev))
- return true;
+ return all_ok;
+
+ if (wdev->valid_links) {
+ radio_idx = cfg80211_get_radio_idx_by_chan(wdev->wiphy, chan);
+ if (radio_idx < 0)
+ return !all_ok;
Why? Do you have a code style that says "don't return constants" or
something? I feel like I comment on this repeatedly - please don't use
variables for constant (return) values, it just makes it harder to read
and easier to modify the wrong way.
Thanks for the feedback. You're right, using a variable for a constant
return value in this case doesn't add clarity and could make the code
harder to follow. Will update this in the next patch
@@ -9777,20 +9784,33 @@ static bool cfg80211_off_channel_oper_allowed(struct wireless_dev *wdev,
/* we cannot leave radar channels */
for_each_valid_link(wdev, link_id) {
struct cfg80211_chan_def *chandef;
+ int link_radio_idx;
chandef = wdev_chandef(wdev, link_id);
if (!chandef || !chandef->chan)
continue;
+ if (!(chandef->chan->flags & IEEE80211_CHAN_RADAR))
+ continue;
+
/*
- * FIXME: don't require all_ok, but rather check only the
- * correct HW resource/link onto which 'chan' falls,
- * as only that link leaves the channel for doing
- * the off-channel operation.
+ * chandef->chan is a radar channel. If the radio/link onto
+ * which this radar channel falls is the same radio/link onto
+ * which the input 'chan' falls, off-channel operation should
+ * not be allowed. Hence, set 'all_ok' to false.
*/
- if (chandef->chan->flags & IEEE80211_CHAN_RADAR)
+ if (wdev->valid_links) {
+ link_radio_idx = cfg80211_get_radio_idx_by_chan(wdev->wiphy,
+ chandef->chan);
+ if (link_radio_idx < 0 ||
+ link_radio_idx == radio_idx) {
+ all_ok = false;
+ break;
+ }
+ } else {
all_ok = false;
+ }
It seems you could simplify this a lot by just unconditionally assigning
the "radio_idx", possibly to -1, and then if it matches you refuse?
I don't see how link_radio_idx<0 could even happen, with a multi-radio
interface that's _already operating_ on that chandef?
Working on this. Will update this as well in the next patch
johannes
