6.17-stable review patch. If anyone has any objections, please let me know.
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From: Bitterblue Smith rtl8821cerfe2@gmail.com
commit e837b9091b277ae6f309d7e9fc93cb0308cf461f upstream.
Scanning can be offloaded to the firmware. To that end, the driver prepares a list of channels to scan, including periodic visits back to the operating channel, and sends the list to the firmware.
When the channel list is too long to fit in a single H2C message, the driver splits the list, sends the first part, and tells the firmware to scan. When the scan is complete, the driver sends the next part of the list and tells the firmware to scan.
When the last channel that fit in the H2C message is the operating channel something seems to go wrong in the firmware. It will acknowledge receiving the list of channels but apparently it will not do anything more. The AP can't be pinged anymore. The driver still receives beacons, though.
One way to avoid this is to split the list of channels before the operating channel.
Affected devices:
* RTL8851BU with firmware 0.29.41.3 * RTL8832BU with firmware 0.29.29.8 * RTL8852BE with firmware 0.29.29.8
The commit 57a5fbe39a18 ("wifi: rtw89: refactor flow that hw scan handles channel list") is found by git blame, but it is actually to refine the scan flow, but not a culprit, so skip Fixes tag.
Reported-by: Bitterblue Smith rtl8821cerfe2@gmail.com Closes: https://lore.kernel.org/linux-wireless/0abbda91-c5c2-4007-84c8-215679e652e1@... Cc: stable@vger.kernel.org # 6.16+ Signed-off-by: Bitterblue Smith rtl8821cerfe2@gmail.com Acked-by: Ping-Ke Shih pkshih@realtek.com Signed-off-by: Ping-Ke Shih pkshih@realtek.com Link: https://patch.msgid.link/c1e61744-8db4-4646-867f-241b47d30386@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/wireless/realtek/rtw89/fw.c | 7 +++++++ 1 file changed, 7 insertions(+)
--- a/drivers/net/wireless/realtek/rtw89/fw.c +++ b/drivers/net/wireless/realtek/rtw89/fw.c @@ -7705,6 +7705,13 @@ int rtw89_hw_scan_add_chan_list_be(struc INIT_LIST_HEAD(&list);
list_for_each_entry_safe(ch_info, tmp, &scan_info->chan_list, list) { + /* The operating channel (tx_null == true) should + * not be last in the list, to avoid breaking + * RTL8851BU and RTL8832BU. + */ + if (list_len + 1 == RTW89_SCAN_LIST_LIMIT_AX && ch_info->tx_null) + break; + list_move_tail(&ch_info->list, &list);
list_len++;