This is a note to let you know that I've just added the patch titled

ath10k: fix incorrect txpower set by P2P_DEVICE interface

to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: ath10k-fix-incorrect-txpower-set-by-p2p_device-interface.patch and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From foo@baz Tue Nov 28 10:49:28 CET 2017

From: Ryan Hsu ryanhsu@qca.qualcomm.com Date: Tue, 13 Dec 2016 14:55:19 -0800 Subject: ath10k: fix incorrect txpower set by P2P_DEVICE interface

From: Ryan Hsu ryanhsu@qca.qualcomm.com

[ Upstream commit 88407beb1b1462f706a1950a355fd086e1c450b6 ]

Ath10k reports the phy capability that supports P2P_DEVICE interface.

When we use the P2P supported wpa_supplicant to start connection, it'll create two interfaces, one is wlan0 (vdev_id=0) and one is P2P_DEVICE p2p-dev-wlan0 which is for p2p control channel (vdev_id=1).

ath10k_pci mac vdev create 0 (add interface) type 2 subtype 0 ath10k_add_interface: vdev_id: 0, txpower: 0, bss_power: 0 ... ath10k_pci mac vdev create 1 (add interface) type 2 subtype 1 ath10k_add_interface: vdev_id: 1, txpower: 0, bss_power: 0

And the txpower in per vif bss_conf will only be set to valid tx power when the interface is assigned with channel_ctx.

But this P2P_DEVICE interface will never be used for any connection, so that the uninitialized bss_conf.txpower=0 is assinged to the arvif->txpower when interface created.

Since the txpower configuration is firmware per physical interface. So the smallest txpower of all vifs will be the one limit the tx power of the physical device, that causing the low txpower issue on other active interfaces.

wlan0: Limiting TX power to 21 (24 - 3) dBm ath10k_pci mac vdev_id 0 txpower 21 ath10k_mac_txpower_recalc: vdev_id: 1, txpower: 0 ath10k_mac_txpower_recalc: vdev_id: 0, txpower: 21 ath10k_pci mac txpower 0

This issue only happens when we use the wpa_supplicant that supports P2P or if we use the iw tool to create the control P2P_DEVICE interface.

Signed-off-by: Ryan Hsu ryanhsu@qca.qualcomm.com Signed-off-by: Kalle Valo kvalo@qca.qualcomm.com Signed-off-by: Sasha Levin alexander.levin@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/wireless/ath/ath10k/mac.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)

--- a/drivers/net/wireless/ath/ath10k/mac.c +++ b/drivers/net/wireless/ath/ath10k/mac.c @@ -4668,7 +4668,8 @@ static int ath10k_mac_txpower_recalc(str lockdep_assert_held(&ar->conf_mutex);

list_for_each_entry(arvif, &ar->arvifs, list) { - WARN_ON(arvif->txpower < 0); + if (arvif->txpower <= 0) + continue;

if (txpower == -1) txpower = arvif->txpower; @@ -4676,8 +4677,8 @@ static int ath10k_mac_txpower_recalc(str txpower = min(txpower, arvif->txpower); }

- if (WARN_ON(txpower == -1)) - return -EINVAL; + if (txpower == -1) + return 0;

ret = ath10k_mac_txpower_setup(ar, txpower); if (ret) {

Patches currently in stable-queue which might be from ryanhsu@qca.qualcomm.com are

queue-4.9/ath10k-fix-incorrect-txpower-set-by-p2p_device-interface.patch queue-4.9/ath10k-ignore-configuring-the-incorrect-board_id.patch