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623dae3e70
Fix a boot hang issue triggered when a USB3 device is incorrectly assumed
to be tunneled over USB4, thus attempting to create a device link between
the USB3 "consumer" device and the USB4 "supplier" Host Interface before
the USB4 side is properly bound to a driver.
This could happen if xhci isn't capable of detecting tunneled devices,
but ACPI tables contain all info needed to assume device is tunneled.
i.e. udev->tunnel_mode == USB_LINK_UNKNOWN.
It turns out that even for actual tunneled USB3 devices it can't be
assumed that the thunderbolt driver providing the tunnel is loaded
before the tunneled USB3 device is created.
The tunnel can be created by BIOS and remain in use by thunderbolt/USB4
host driver once it loads.
Solve this by making the device link "stateless", which doesn't create
a driver presence order dependency between the supplier and consumer
drivers.
It still guarantees correct suspend/resume and shutdown ordering.
cc: Mario Limonciello <mario.limonciello@amd.com>
Fixes: f1bfb4a6fe ("usb: acpi: add device link between tunneled USB3 device and USB4 Host Interface")
Tested-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Mario Limonciello <mario.limonciello@amd.com>
Link: https://lore.kernel.org/r/20241024131355.3836538-1-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.