From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from endrift.com (endrift.com [173.255.198.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3C08040DB3C for ; Fri, 7 Aug 2026 23:25:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=173.255.198.10 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786145119; cv=none; b=VBJKhGJs6CPNo4U2DXLZYhsq2p2JknRqT5I7ZEcNWv0TIzfz0iRyNG5J6agCGNdFLQvbMwSh3QCyZ2pcyWcfpJrn6jBwDSL+6sVfVrmQrBtxzCDjYNk+0xDdaVtUuInD7DkPB6xud33yASePniBPsi1FxGaauv5WhYhw41ecIRg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786145119; c=relaxed/simple; bh=+Cuc3sXJqGju3oEhxymuo9J408SUyGWwjVSk9t9eehI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=REwU0560my0yj4rslekji7UsBBruYCyVpydqCWOrKIdHTdsCb7nO+MJ+eX3yM/7RNhXiHcfgQKTYU/FclXvRnZQymol0uZdjt/TZre05yo9Mnq5epl74j96/TjhIKZRVAAzHZ66xC60vZAAJ6BdzZybuLFoN6tYcp8lFXHlGhGE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=endrift.com; spf=pass smtp.mailfrom=endrift.com; dkim=pass (2048-bit key) header.d=endrift.com header.i=@endrift.com header.b=PQ0Rk3+s; arc=none smtp.client-ip=173.255.198.10 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=endrift.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=endrift.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=endrift.com header.i=@endrift.com header.b="PQ0Rk3+s" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=endrift.com; s=2020; t=1786145107; bh=+Cuc3sXJqGju3oEhxymuo9J408SUyGWwjVSk9t9eehI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PQ0Rk3+s3fzJSSCME8d6lk06lqDvh11l3a3n8SFOf8BS0mqUsr4jRg3+KbO5zF/0a 7Gt/ouP/ljKb1RTOclbIgM6KPaPStoxEysyhKkSVh5XQx2zbYkrJCK6TS9sYu1c1xT YRiHB0O3fOvmLuNG71PQppAhGk8uzYv83fDidVxnBElvX9zP093r5rr0D5E7PR/a9x PgKaStQoVFrTKTELyn7ViBs8tcJgO1RZrqve2oLDNMh5mJPeQju9HKWVX7ZcV5Cb32 pxH4XR+jbrnrXDmFrS6jaKxkHpHHKPbUCqLewDb11x4sGAgh1jiCsPXAXrbulVl87A Z7u5OsHlcs6Vg== Received: from microtis.vulpes.eutheria.net (71-212-73-87.tukw.qwest.net [71.212.73.87]) by endrift.com (Postfix) with ESMTPSA id 1A5DF132034; Fri, 07 Aug 2026 16:25:07 -0700 (PDT) From: Vicki Pfau To: Jiri Kosina , Benjamin Tissoires , linux-input@vger.kernel.org Cc: Vicki Pfau Subject: [PATCH v4 5/6] HID: steam: Clean up locking Date: Fri, 7 Aug 2026 16:23:36 -0700 Message-ID: <20260807232339.2799205-6-vi@endrift.com> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260807232339.2799205-1-vi@endrift.com> References: <20260807232339.2799205-1-vi@endrift.com> Precedence: bulk X-Mailing-List: linux-input@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit This cleans up several issues with locking behavior, including RCU accesses not being guarded behind a lock. Signed-off-by: Vicki Pfau --- drivers/hid/hid-steam.c | 100 +++++++++++++++++++++------------------- 1 file changed, 52 insertions(+), 48 deletions(-) diff --git a/drivers/hid/hid-steam.c b/drivers/hid/hid-steam.c index d95296b28f92..95e252665351 100644 --- a/drivers/hid/hid-steam.c +++ b/drivers/hid/hid-steam.c @@ -403,6 +403,7 @@ struct steam_device { spinlock_t lock; struct hid_device *hdev, *client_hdev; struct mutex report_mutex; + struct mutex registration_mutex; unsigned long client_opened; struct input_dev __rcu *input; struct input_dev __rcu *sensors; @@ -633,7 +634,6 @@ static int steam_exchange_report(struct steam_device *steam, u8 *cmd, int csize, unsigned int retries = 5; int ret; - guard(mutex)(&steam->report_mutex); do { ret = steam_send_report(steam, cmd, csize); if (ret < 0) @@ -787,7 +787,6 @@ static inline int steam_haptic_pulse(struct steam_device *steam, u8 pad, report[8] = count >> 8; report[9] = gain; - guard(mutex)(&steam->report_mutex); ret = steam_send_report(steam, report, 10); } @@ -829,7 +828,6 @@ static inline int steam_haptic_rumble(struct steam_device *steam, report[9] = left_gain; report[10] = right_gain; - guard(mutex)(&steam->report_mutex); ret = steam_send_report(steam, report, sizeof(report)); } return ret; @@ -840,8 +838,10 @@ static void steam_haptic_rumble_cb(struct work_struct *work) struct steam_device *steam = container_of(work, struct steam_device, rumble_work); + mutex_lock(&steam->report_mutex); steam_haptic_rumble(steam, 0, steam->rumble_left, steam->rumble_right, 2, 0); + mutex_unlock(&steam->report_mutex); } static void steam_coalesce_rumble_cb(struct work_struct *work) @@ -850,8 +850,10 @@ static void steam_coalesce_rumble_cb(struct work_struct *work) struct steam_device, coalesce_rumble_work); + mutex_lock(&steam->report_mutex); steam_haptic_rumble(steam, 0, steam->rumble_left, steam->rumble_right, 2, 0); + mutex_unlock(&steam->report_mutex); if (steam->rumble_left || steam->rumble_right) schedule_delayed_work(&steam->coalesce_rumble_work, HZ / 20); @@ -883,7 +885,6 @@ static void steam_set_lizard_mode(struct steam_device *steam, bool enable) if (steam->gamepad_mode) enable = false; - mutex_lock(&steam->report_mutex); if (enable) { /* enable esc, enter, cursors */ steam_send_report_byte(steam, ID_SET_DEFAULT_DIGITAL_MAPPINGS); @@ -906,14 +907,13 @@ static void steam_set_lizard_mode(struct steam_device *steam, bool enable) SETTING_RIGHT_TRACKPAD_MODE, TRACKPAD_NONE, /* disable mouse */ 0); } - mutex_unlock(&steam->report_mutex); } static int steam_input_open(struct input_dev *dev) { struct steam_device *steam = input_get_drvdata(dev); unsigned long flags; - bool set_lizard_mode; + bool client_opened; /* * Disabling lizard mode automatically is only done on the Steam @@ -922,9 +922,10 @@ static int steam_input_open(struct input_dev *dev) */ if (!(steam->quirks & (STEAM_QUIRK_DECK | STEAM_QUIRK_IBEX))) { spin_lock_irqsave(&steam->lock, flags); - set_lizard_mode = !steam->client_opened && lizard_mode; + client_opened = steam->client_opened; spin_unlock_irqrestore(&steam->lock, flags); - if (set_lizard_mode) + guard(mutex)(&steam->report_mutex); + if (!client_opened && lizard_mode) steam_set_lizard_mode(steam, false); } @@ -935,13 +936,14 @@ static void steam_input_close(struct input_dev *dev) { struct steam_device *steam = input_get_drvdata(dev); unsigned long flags; - bool set_lizard_mode; + bool client_opened; if (!(steam->quirks & (STEAM_QUIRK_DECK | STEAM_QUIRK_IBEX))) { spin_lock_irqsave(&steam->lock, flags); - set_lizard_mode = !steam->client_opened && lizard_mode; + client_opened = steam->client_opened; spin_unlock_irqrestore(&steam->lock, flags); - if (set_lizard_mode) + guard(mutex)(&steam->report_mutex); + if (!client_opened && lizard_mode) steam_set_lizard_mode(steam, true); } } @@ -949,14 +951,11 @@ static void steam_input_close(struct input_dev *dev) static int steam_sensor_open(struct input_dev *dev) { struct steam_device *steam = input_get_drvdata(dev); - unsigned long flags; - bool client_opened; - spin_lock_irqsave(&steam->lock, flags); - client_opened = steam->client_opened; - spin_unlock_irqrestore(&steam->lock, flags); - if (client_opened) - return 0; + scoped_guard(spinlock_irqsave, &steam->lock) { + if (steam->client_opened) + return 0; + } guard(mutex)(&steam->report_mutex); steam_write_settings(steam, SETTING_IMU_MODE, @@ -969,14 +968,11 @@ static int steam_sensor_open(struct input_dev *dev) static void steam_sensor_close(struct input_dev *dev) { struct steam_device *steam = input_get_drvdata(dev); - unsigned long flags; - bool client_opened; - spin_lock_irqsave(&steam->lock, flags); - client_opened = steam->client_opened; - spin_unlock_irqrestore(&steam->lock, flags); - if (client_opened) - return; + scoped_guard(spinlock_irqsave, &steam->lock) { + if (steam->client_opened) + return; + } guard(mutex)(&steam->report_mutex); steam_write_settings(steam, SETTING_IMU_MODE, 0, 0); @@ -1380,13 +1376,16 @@ static int steam_register(struct steam_device *steam) { int ret; + mutex_lock(&steam->registration_mutex); /* * This function can be called several times in a row with the * wireless adaptor, without steam_unregister() between them, because * another client send a get_connection_status command, for example. */ - if (steam->registered) + if (steam->registered) { + mutex_unlock(&steam->registration_mutex); return 0; + } /* * Unlikely, but getting the serial could fail, and it is not so @@ -1419,6 +1418,7 @@ static int steam_register(struct steam_device *steam) goto steam_register_sensors_fail; steam->registered = true; + mutex_unlock(&steam->registration_mutex); mutex_lock(&steam_devices_lock); if (list_empty(&steam->list)) list_add(&steam->list, &steam_devices); @@ -1429,6 +1429,7 @@ static int steam_register(struct steam_device *steam) steam_input_unregister(steam); steam_register_input_fail: steam_battery_unregister(steam); + mutex_unlock(&steam->registration_mutex); return ret; } @@ -1440,10 +1441,12 @@ static void steam_unregister(struct steam_device *steam) hid_info(steam->hdev, "Steam %s '%s' disconnected", steam->quirks & STEAM_QUIRK_DECK ? "Deck" : "Controller", steam->serial_no); + mutex_lock(&steam->registration_mutex); steam->registered = false; steam_battery_unregister(steam); steam_sensors_unregister(steam); steam_input_unregister(steam); + mutex_unlock(&steam->registration_mutex); cancel_work_sync(&steam->rumble_work); cancel_delayed_work_sync(&steam->mode_switch); cancel_delayed_work_sync(&steam->coalesce_rumble_work); @@ -1484,23 +1487,26 @@ static void steam_mode_switch_cb(struct work_struct *work) struct steam_device, mode_switch); unsigned long flags; bool client_opened; + bool gamepad_mode; + if (!lizard_mode) return; + spin_lock_irqsave(&steam->lock, flags); steam->gamepad_mode = !steam->gamepad_mode; - hid_dbg(steam->hdev, "%s: switching gamepad mode to %i\n", __func__, steam->gamepad_mode); - if (steam->gamepad_mode) + gamepad_mode = steam->gamepad_mode; + client_opened = steam->client_opened; + spin_unlock_irqrestore(&steam->lock, flags); + + guard(mutex)(&steam->report_mutex); + hid_dbg(steam->hdev, "%s: switching gamepad mode to %i\n", __func__, gamepad_mode); + if (gamepad_mode) steam_set_lizard_mode(steam, false); - else { - spin_lock_irqsave(&steam->lock, flags); - client_opened = steam->client_opened; - spin_unlock_irqrestore(&steam->lock, flags); - if (!client_opened) - steam_set_lizard_mode(steam, lizard_mode); - } + else if (!client_opened) + steam_set_lizard_mode(steam, lizard_mode); steam_haptic_pulse(steam, STEAM_PAD_RIGHT, 0x190, 0, 1, 0); - if (steam->gamepad_mode) { + if (gamepad_mode) { steam_haptic_pulse(steam, STEAM_PAD_LEFT, 0x14D, 0x14D, 0x2D, 0); } else { steam_haptic_pulse(steam, STEAM_PAD_LEFT, 0x1F4, 0x1F4, 0x1E, 0); @@ -1687,6 +1693,7 @@ static int steam_probe(struct hid_device *hdev, hid_set_drvdata(hdev, steam); spin_lock_init(&steam->lock); mutex_init(&steam->report_mutex); + mutex_init(&steam->registration_mutex); steam->quirks = id->driver_data; INIT_WORK(&steam->work_connect, steam_work_connect_cb); INIT_DELAYED_WORK(&steam->mode_switch, steam_mode_switch_cb); @@ -1795,13 +1802,10 @@ static void steam_remove(struct hid_device *hdev) static void steam_do_connect_event(struct steam_device *steam, bool connected) { - unsigned long flags; bool changed; - spin_lock_irqsave(&steam->lock, flags); changed = steam->connected != connected; steam->connected = connected; - spin_unlock_irqrestore(&steam->lock, flags); if (changed && schedule_work(&steam->work_connect) == 0) dbg_hid("%s: connected=%d event already queued\n", @@ -2230,8 +2234,6 @@ static void steam_do_deck_sensors_event(struct steam_device *steam, static void steam_do_battery_event(struct steam_device *steam, struct power_supply *battery, u8 *data) { - unsigned long flags; - s16 volts = steam_le16(data + 12); u8 batt = data[14]; @@ -2239,10 +2241,8 @@ static void steam_do_battery_event(struct steam_device *steam, rcu_read_lock(); battery = rcu_dereference(steam->battery); if (likely(battery)) { - spin_lock_irqsave(&steam->lock, flags); steam->battery_voltage = volts; steam->battery_charge = batt; - spin_unlock_irqrestore(&steam->lock, flags); power_supply_changed(battery); } rcu_read_unlock(); @@ -2427,15 +2427,12 @@ static void steam_do_ibex_battery_event(struct steam_device *steam, struct power_supply *battery, const struct steam_ibex_battery_status *data) { - unsigned long flags; - /* Creating the battery may have failed */ guard(rcu)(); battery = rcu_dereference(steam->battery); if (!likely(battery)) return; - spin_lock_irqsave(&steam->lock, flags); steam->battery_voltage = get_unaligned_le16(&data->battery_voltage); steam->battery_current = get_unaligned_le16(&data->battery_current); steam->battery_temp = get_unaligned_le16(&data->temperature); @@ -2454,7 +2451,6 @@ static void steam_do_ibex_battery_event(struct steam_device *steam, steam->battery_status = POWER_SUPPLY_STATUS_UNKNOWN; break; } - spin_unlock_irqrestore(&steam->lock, flags); power_supply_changed(battery); } @@ -2470,6 +2466,7 @@ static int steam_raw_event(struct hid_device *hdev, if (!steam) return 0; + guard(spinlock_irqsave)(&steam->lock); if (steam->client_opened) hid_input_report(steam->client_hdev, report->type, data, size, 0); @@ -2633,6 +2630,8 @@ static int steam_param_set_lizard_mode(const char *val, { struct steam_device *steam; int ret; + bool client_opened; + unsigned long flags; ret = param_set_bool(val, kp); if (ret) @@ -2640,8 +2639,13 @@ static int steam_param_set_lizard_mode(const char *val, mutex_lock(&steam_devices_lock); list_for_each_entry(steam, &steam_devices, list) { - if (!steam->client_opened) + spin_lock_irqsave(&steam->lock, flags); + client_opened = steam->client_opened; + spin_unlock_irqrestore(&steam->lock, flags); + if (!client_opened) { + guard(mutex)(&steam->report_mutex); steam_set_lizard_mode(steam, lizard_mode); + } } mutex_unlock(&steam_devices_lock); return 0; -- 2.54.0