linux-kernel - [PATCH RESEND v3] Bluetooth: btusb: mediatek: fix WMT command failure during runtime suspend

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Date:   Fri, 29 Jul 2022 22:43:49 +0800
From:   <sean.wang@...iatek.com>
To:     <marcel@...tmann.org>, <johan.hedberg@...il.com>,
        <luiz.dentz@...il.com>
CC:     <sean.wang@...iatek.com>, <Soul.Huang@...iatek.com>,
        <YN.Chen@...iatek.com>, <Leon.Yen@...iatek.com>,
        <Eric-SY.Chang@...iatek.com>, <Deren.Wu@...iatek.com>,
        <km.lin@...iatek.com>, <robin.chiu@...iatek.com>,
        <Eddie.Chen@...iatek.com>, <ch.yeh@...iatek.com>,
        <posh.sun@...iatek.com>, <ted.huang@...iatek.com>,
        <Stella.Chang@...iatek.com>, <Tom.Chou@...iatek.com>,
        <steve.lee@...iatek.com>, <jsiuda@...gle.com>,
        <frankgor@...gle.com>, <abhishekpandit@...gle.com>,
        <michaelfsun@...gle.com>, <mcchou@...omium.org>,
        <shawnku@...gle.com>, <linux-bluetooth@...r.kernel.org>,
        <linux-mediatek@...ts.infradead.org>,
        <linux-kernel@...r.kernel.org>, "Jing Cai" <jing.cai@...iatek.com>
Subject: [PATCH RESEND v3] Bluetooth: btusb: mediatek: fix WMT command failure during runtime suspend

From: Sean Wang <sean.wang@...iatek.com>

WMT cmd/event doesn't follow up the generic HCI cmd/event handling, it
needs constantly polling control pipe until the host received the WMT
event, thus, we should require to specifically acquire PM counter on the
USB to prevent the interface from entering auto suspended while WMT
cmd/event in progress.

Fixes: a1c49c434e15 ("Bluetooth: btusb: Add protocol support for MediaTek MT7668U USB devices")
Co-developed-by: Jing Cai <jing.cai@...iatek.com>
Signed-off-by: Jing Cai <jing.cai@...iatek.com>
Signed-off-by: Sean Wang <sean.wang@...iatek.com>
---
v2:
1. move usb_autopm_[get, put]_interface to btusb_mtk_hci_wmt_sync whenever
wmt cmd is invoked.
2. add the explanation why we needed the specific
usb_autopm_[get, put]_interface there.

v3: correct the version and there is no logic changed
---
 drivers/bluetooth/btusb.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index 480ea891c09a..bdcfc3deea6c 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -2453,15 +2453,29 @@ static int btusb_mtk_hci_wmt_sync(struct hci_dev *hdev,
 
 	set_bit(BTUSB_TX_WAIT_VND_EVT, &data->flags);
 
+	/* WMT cmd/event doesn't follow up the generic HCI cmd/event handling,
+	 * it needs constantly polling control pipe until the host received the
+	 * WMT event, thus, we should require to specifically acquire PM counter
+	 * on the USB to prevent the interface from entering auto suspended
+	 * while WMT cmd/event in progress.
+	 */
+	err = usb_autopm_get_interface(data->intf);
+	if (err < 0)
+		goto err_free_wc;
+
 	err = __hci_cmd_send(hdev, 0xfc6f, hlen, wc);
 
 	if (err < 0) {
 		clear_bit(BTUSB_TX_WAIT_VND_EVT, &data->flags);
+		usb_autopm_put_interface(data->intf);
 		goto err_free_wc;
 	}
 
 	/* Submit control IN URB on demand to process the WMT event */
 	err = btusb_mtk_submit_wmt_recv_urb(hdev);
+
+	usb_autopm_put_interface(data->intf);
+
 	if (err < 0)
 		goto err_free_wc;
 
-- 
2.25.1