From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 EBA1F3C1D66; Tue, 13 Oct 2026 14:06:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791900408; cv=none; b=J3RcLtE6L05SJgUVH2FagI82pzYSxFMvw38GOv8/hBZ4WcB8Dv61FsowxOEV1F5VqtilNbPLbA/59QQ4E0vfydau9D+yiPXmC+1WhlU7dDoh6jfAoS62+9f2HlTiZpzb3WRQUpke44rxunq5zUfdB1TkWB7dYsa0RkuodIbmpj0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791900408; c=relaxed/simple; bh=qBM0oFJyiP5nGCBoW1aU1ZOtHYPwrvo1e/jOSOMCWDM=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=SxDE6+7QzwqY7tp9NKzWGyaK/HV6+1R6yKDo4yaZX2vNozyBS1MzH0jMCm1pIx/swK3lSCxLeavs/BlTJ21pHdTuFURboJDo/WTAbNTkJZ6CHBUVvWslGyUuW13qL3M7mpn//O7QjUQ0hdrtkhhPwTuLnXottwj/zR/KKNgueuU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=HiLs+rR0; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="HiLs+rR0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8335B1F000FF; Tue, 13 Oct 2026 14:06:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1791900406; bh=noQ+gtaIeSfcBbf4IVs7251oKyPHxgZa73oom00Xu90=; h=From:To:Cc:Subject:Date; b=HiLs+rR0/BU9LaVyfSNKyQlc22NVHi9JbrV1sUZgBhxd7aIy9ee7hKX2iWAt4I3Ma 5Nj12dmK8i0N5XNfbLZ+/r5D3N/+jaHm2RoU0OLOpJ3ceA/QLAgS2bPpfd+yEwJP++ DPRFXwDbJQSleg1sRhzazw7hl39RTzlaCmN1LGFWcx0WSs8pjQ8bYaimrZp8RpM7h6 aFqWt3/TM19zLSSz1/Gaf3+kN2UdCU3Ow5t9hUCsoJGaogqj/U3PGxW/wKxweHMiOk GgjCJfN6bPqGzSxT3TD1ClDHqwFVb4hthzlRtlZusdNDEvavjDGbRQ5twSsxP+23kI P1bzV9lOy124Q== Received: from johan by xi.lan with local (Exim 4.99.5) (envelope-from ) id 1xGd9Q-000000059Ct-1yfW; Tue, 13 Oct 2026 16:06:44 +0200 From: Johan Hovold To: Greg Kroah-Hartman , "Rafael J. Wysocki" , Danilo Krummrich , Johan Hovold Cc: Dmitry Torokhov , Alan Stern , driver-core@lists.linux.dev, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Mario Peter , stable@vger.kernel.org Subject: [PATCH] driver core: take parent lock on deferred probe Date: Tue, 13 Oct 2026 16:06:15 +0200 Message-ID: <20261013140615.1226992-1-johan@kernel.org> X-Mailer: git-send-email 2.55.0 Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit USB interfaces should be probed with the parent USB device lock held, but this is not honoured when probe is deferred. Add a new bus_probe_device_deferred() helper to handle deferred probe where the parent device lock is not held. Fixes: d1c3414c2a9d ("drivercore: Add driver probe deferral mechanism") Reported-by: Mario Peter Link: https://lore.kernel.org/20261007131514.1260696-1-mario.peter@leica-geosystems.com Cc: stable@vger.kernel.org # 3.4 Signed-off-by: Johan Hovold --- drivers/base/base.h | 1 + drivers/base/bus.c | 28 +++++++++++++++++++++------- drivers/base/dd.c | 7 ++++--- 3 files changed, 26 insertions(+), 10 deletions(-) diff --git a/drivers/base/base.h b/drivers/base/base.h index a5b7abc10ff0..3c36a2128f88 100644 --- a/drivers/base/base.h +++ b/drivers/base/base.h @@ -154,6 +154,7 @@ struct kobject *virtual_device_parent(void); int bus_add_device(struct device *dev); void bus_probe_device(struct device *dev); +void bus_probe_device_deferred(struct device *dev); void bus_remove_device(struct device *dev); void bus_notify(struct device *dev, enum bus_notifier_event value); bool bus_is_registered(const struct bus_type *bus); diff --git a/drivers/base/bus.c b/drivers/base/bus.c index c51ad96d4de4..fd62594eb6f9 100644 --- a/drivers/base/bus.c +++ b/drivers/base/bus.c @@ -606,13 +606,7 @@ int bus_add_device(struct device *dev) return error; } -/** - * bus_probe_device - probe drivers for a new device - * @dev: device to probe - * - * - Automatically probe for a driver if the bus allows it. - */ -void bus_probe_device(struct device *dev) +static void __bus_probe_device(struct device *dev) { struct subsys_private *sp = bus_to_subsys(dev->bus); struct subsys_interface *sif; @@ -630,6 +624,26 @@ void bus_probe_device(struct device *dev) subsys_put(sp); } +/** + * bus_probe_device - probe drivers for a new device + * @dev: device to probe + * + * - Automatically probe for a driver if the bus allows it. + */ +void bus_probe_device(struct device *dev) +{ + __bus_probe_device(dev); +} + +void bus_probe_device_deferred(struct device *dev) +{ + if (dev->parent && dev->bus->need_parent_lock) + device_lock(dev->parent); + __bus_probe_device(dev); + if (dev->parent && dev->bus->need_parent_lock) + device_unlock(dev->parent); +} + /** * bus_remove_device - remove device from bus * @dev: device to be removed diff --git a/drivers/base/dd.c b/drivers/base/dd.c index 9dc7cce9bd8d..87962f4e914c 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -86,8 +86,9 @@ static void deferred_probe_work_func(struct work_struct *work) /* * This block processes every device in the deferred 'active' list. * Each device is removed from the active list and passed to - * bus_probe_device() to re-attempt the probe. The loop continues - * until every device in the active list is removed and retried. + * bus_probe_device_deferred() to re-attempt the probe. The loop + * continues until every device in the active list is removed and + * retried. * * Note: Once the device is removed from the list and the mutex is * released, it is possible for the device get freed by another thread @@ -121,7 +122,7 @@ static void deferred_probe_work_func(struct work_struct *work) device_pm_move_to_tail(dev); dev_dbg(dev, "Retrying from deferred list\n"); - bus_probe_device(dev); + bus_probe_device_deferred(dev); mutex_lock(&deferred_probe_mutex); put_device(dev); -- 2.55.0