Message ID | 20241024131355.3836538-1-mathias.nyman@linux.intel.com (mailing list archive) |
---|---|
State | Accepted |
Commit | 623dae3e7084a9504e6dc4cf0cb83f305f413b4d |
Headers | show |
Series | [v2] usb: acpi: fix boot hang due to early incorrect 'tunneled' USB3 device links | expand |
On 10/24/2024 08:13, Mathias Nyman wrote: > 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: f1bfb4a6fed6 ("usb: acpi: add device link between tunneled USB3 device and USB4 Host Interface") > Tested-by: Harry Wentland <harry.wentland@amd.com> Tested-by: Mario Limonciello <mario.limonciello@amd.com> > Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> > --- > v2: Use stateless device link instead of checking if driver is bound > > drivers/usb/core/usb-acpi.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/usb/core/usb-acpi.c b/drivers/usb/core/usb-acpi.c > index 21585ed89ef8..03c22114214b 100644 > --- a/drivers/usb/core/usb-acpi.c > +++ b/drivers/usb/core/usb-acpi.c > @@ -170,11 +170,11 @@ static int usb_acpi_add_usb4_devlink(struct usb_device *udev) > struct fwnode_handle *nhi_fwnode __free(fwnode_handle) = > fwnode_find_reference(dev_fwnode(&port_dev->dev), "usb4-host-interface", 0); > > - if (IS_ERR(nhi_fwnode)) > + if (IS_ERR(nhi_fwnode) || !nhi_fwnode->dev) > return 0; > > link = device_link_add(&port_dev->child->dev, nhi_fwnode->dev, > - DL_FLAG_AUTOREMOVE_CONSUMER | > + DL_FLAG_STATELESS | > DL_FLAG_RPM_ACTIVE | > DL_FLAG_PM_RUNTIME); > if (!link) {
On Thu, Oct 24, 2024 at 04:13:55PM +0300, Mathias Nyman wrote: > 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: f1bfb4a6fed6 ("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>
diff --git a/drivers/usb/core/usb-acpi.c b/drivers/usb/core/usb-acpi.c index 21585ed89ef8..03c22114214b 100644 --- a/drivers/usb/core/usb-acpi.c +++ b/drivers/usb/core/usb-acpi.c @@ -170,11 +170,11 @@ static int usb_acpi_add_usb4_devlink(struct usb_device *udev) struct fwnode_handle *nhi_fwnode __free(fwnode_handle) = fwnode_find_reference(dev_fwnode(&port_dev->dev), "usb4-host-interface", 0); - if (IS_ERR(nhi_fwnode)) + if (IS_ERR(nhi_fwnode) || !nhi_fwnode->dev) return 0; link = device_link_add(&port_dev->child->dev, nhi_fwnode->dev, - DL_FLAG_AUTOREMOVE_CONSUMER | + DL_FLAG_STATELESS | DL_FLAG_RPM_ACTIVE | DL_FLAG_PM_RUNTIME); if (!link) {