kernel.git/drivers/usb/core/port.c, branch linux-6.7.y

USB: core: Fix deadlock in port "disable" sysfs attribute

2024-04-03T13:11:55Z

commit f4d1960764d8a70318b02f15203a1be2b2554ca1 upstream. The show and store callback routines for the "disable" sysfs attribute file in port.c acquire the device lock for the port's parent hub device. This can cause problems if another process has locked the hub to remove it or change its configuration: Removing the hub or changing its configuration requires the hub interface to be removed, which requires the port device to be removed, and device_del() waits until all outstanding sysfs attribute callbacks for the ports have returned. The lock can't be released until then. But the disable_show() or disable_store() routine can't return until after it has acquired the lock. The resulting deadlock can be avoided by calling sysfs_break_active_protection(). This will cause the sysfs core not to wait for the attribute's callback routine to return, allowing the removal to proceed. The disadvantage is that after making this call, there is no guarantee that the hub structure won't be deallocated at any moment. To prevent this, we have to acquire a reference to it first by calling hub_get(). Signed-off-by: Alan Stern Cc: stable Link: https://lore.kernel.org/r/f7a8c135-a495-4ce6-bd49-405a45e7ea9a@rowland.harvard.edu Signed-off-by: Greg Kroah-Hartman

usb: port: Don't try to peer unused USB ports based on location

2024-04-03T13:11:38Z

commit 69c63350e573367f9c8594162288cffa8a26d0d1 upstream. Unused USB ports may have bogus location data in ACPI PLD tables. This causes port peering failures as these unused USB2 and USB3 ports location may match. Due to these failures the driver prints a "usb: port power management may be unreliable" warning, and unnecessarily blocks port power off during runtime suspend. This was debugged on a couple DELL systems where the unused ports all returned zeroes in their location data. Similar bugreports exist for other systems. Don't try to peer or match ports that have connect type set to USB_PORT_NOT_USED. Fixes: 3bfd659baec8 ("usb: find internal hub tier mismatch via acpi") Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218465 Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218486 Tested-by: Paul Menzel Link: https://lore.kernel.org/linux-usb/5406d361-f5b7-4309-b0e6-8c94408f7d75@molgen.mpg.de Cc: stable@vger.kernel.org # v3.16+ Signed-off-by: Mathias Nyman Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218490 Link: https://lore.kernel.org/r/20240222233343.71856-1-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman

usb: core: Remove duplicated check in usb_hub_create_port_device

2023-10-21T10:53:55Z

Simplify the code by not calling hub_is_superspeed() twice. Signed-off-by: Heiner Kallweit Link: https://lore.kernel.org/r/b1d77cbc-faa3-4d07-94ff-f6ffb85c6964@gmail.com Signed-off-by: Greg Kroah-Hartman

usb: Inform the USB Type-C class about enumerated devices

2023-10-16T18:02:36Z

The Type-C port drivers can make PM related decisions based on is the device USB3 or USB2. Suggested-by: Benson Leung Tested-by: Benson Leung Signed-off-by: Heikki Krogerus Link: https://lore.kernel.org/r/20231011105825.320062-3-heikki.krogerus@linux.intel.com Signed-off-by: Greg Kroah-Hartman

usb: core: add sysfs entry for usb device state

2023-06-13T09:58:26Z

Expose usb device state to userland as the information is useful in detecting non-compliant setups and diagnosing enumeration failures. For example: - End-to-end signal integrity issues: the device would fail port reset repeatedly and thus be stuck in POWERED state. - Charge-only cables (missing D+/D- lines): the device would never enter POWERED state as the HC would not see any pullup. What's the status quo? We do have error logs such as "Cannot enable. Maybe the USB cable is bad?" to flag potential setup issues, but there's no good way to expose them to userspace. Why add a sysfs entry in struct usb_port instead of struct usb_device? The struct usb_device is not device_add() to the system until it's in ADDRESS state hence we would miss the first two states. The struct usb_port is a better place to keep the information because its life cycle is longer than the struct usb_device that is attached to the port. Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-lkp/202306042228.e532af6e-oliver.sang@intel.com Reviewed-by: Alan Stern Signed-off-by: Roy Luo Message-ID: <20230608015913.1679984-1-royluo@google.com> Signed-off-by: Greg Kroah-Hartman

usb: core: stop USB enumeration if too many retries

2022-11-08T15:50:21Z

When a broken USB accessory connects to a USB host, usbcore might keep doing enumeration retries. If the host has a watchdog mechanism, the kernel panic will happen on the host. This patch provides an attribute early_stop to limit the numbers of retries for each port of a hub. If a port was marked with early_stop attribute, unsuccessful connection attempts will fail quickly. In addition, if an early_stop port has failed to initialize, it will ignore all future connection events until early_stop attribute is clear. Signed-off-by: Ray Chi Reviewed-by: Alan Stern Link: https://lore.kernel.org/r/20221107072754.3336357-1-raychi@google.com Signed-off-by: Greg Kroah-Hartman

usb: core: Use kstrtobool() instead of strtobool()

2022-11-03T14:46:01Z

strtobool() is the same as kstrtobool(). However, the latter is more used within the kernel. In order to remove strtobool() and slightly simplify kstrtox.h, switch to the other function name. While at it, include the corresponding header file () Signed-off-by: Christophe JAILLET Link: https://lore.kernel.org/r/f01ef2ddaf12a6412127611617786adc1234e0b4.1667336095.git.christophe.jaillet@wanadoo.fr Signed-off-by: Greg Kroah-Hartman

usb: hub: port: add sysfs entry to switch port power

2022-06-12T04:49:46Z

In some cases the port of an hub needs to be disabled or switched off and on again. E.g. when the connected device needs to be re-enumerated. Or it needs to be explicitly disabled while the rest of the usb tree stays working. For this purpose this patch adds an sysfs switch to enable/disable the port on any hub. In the case the hub is supporting power switching, the power line will be disabled to the connected device. When the port gets disabled, the associated device gets disconnected and removed from the logical usb tree. No further device will be enumerated on that port until the port gets enabled again. Reviewed-by: Alan Stern Signed-off-by: Michael Grzeschik Link: https://lore.kernel.org/r/20220607114522.3359148-1-m.grzeschik@pengutronix.de Signed-off-by: Greg Kroah-Hartman

usb: core: Unregister device on component_add() failure

2022-02-11T09:57:21Z

Commit 8c67d06f3fd9 ("usb: Link the ports to the connectors they are attached to") creates a link to the USB Type-C connector for every new port that is added when possible. If component_add() fails, usb_hub_create_port_device() prints a warning but does not unregister the device and does not return errors to the callers. Syzbot reported a "WARNING in component_del()". Fix this issue in usb_hub_create_port_device by calling device_unregister() and returning the errors from component_add(). Fixes: 8c67d06f3fd9 ("usb: Link the ports to the connectors they are attached to") Reported-and-tested-by: syzbot+60df062e1c41940cae0f@syzkaller.appspotmail.com Reviewed-by: Heikki Krogerus Signed-off-by: Fabio M. De Francesco Link: https://lore.kernel.org/r/20220209164500.8769-1-fmdefrancesco@gmail.com Signed-off-by: Greg Kroah-Hartman

usb: Link the ports to the connectors they are attached to

2021-12-30T11:13:04Z

Creating link to the USB Type-C connector for every new port that is added when possible. Reviewed-by: Andy Shevchenko Acked-by: Rafael J. Wysocki Signed-off-by: Heikki Krogerus Link: https://lore.kernel.org/r/20211223082349.45616-1-heikki.krogerus@linux.intel.com Signed-off-by: Greg Kroah-Hartman