A race condition occurs during system suspend if interrupted between
usb_suspend() and the parent device’s PM suspend (e.g., a power
domain). This triggers PM resume workflows (via usb_resume()), but if
parent device is already runtime-suspended, pm_runtime_set_active()
fails. Subsequent operations like pm_runtime_enable() and interface
unbinding may leave the USB device in an inconsistent state or trigger
unintended behavior.
Found by code review.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 98d9a82e5f75 ("USB: cleanup the handling of the PM complete call")
Signed-off-by: Ma Ke <make24@xxxxxxxxxxx>
---
drivers/usb/core/driver.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index 460d4dde5994..7478fcc11fd4 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -1624,11 +1624,17 @@ int usb_resume(struct device *dev, pm_message_t msg)
status = usb_resume_both(udev, msg);
if (status == 0) {
pm_runtime_disable(dev);
- pm_runtime_set_active(dev);
+ status = pm_runtime_set_active(dev);
+ if (status) {
+ pm_runtime_enable(dev);
+ goto out;
+ }
+
pm_runtime_enable(dev);
unbind_marked_interfaces(udev);
}
+out:
/* Avoid PM error messages for devices disconnected while suspended
* as we'll display regular disconnect messages just a bit later.
*/
--
2.25.1
