6.6-stable review patch. If anyone has any objections, please let me know.
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From: Mathias Nyman mathias.nyman@linux.intel.com
commit 89bb3dc13ac29a563f4e4c555e422882f64742bd upstream.
usb core avoids sending a Set-Interface altsetting 0 request after device reset, and instead relies on calling usb_disable_interface() and usb_enable_interface() to flush and reset host-side of those endpoints.
xHCI hosts allocate and set up endpoint ring buffers and host_ep->hcpriv during usb_hcd_alloc_bandwidth() callback, which in this case is called before flushing the endpoint in usb_disable_interface().
Call usb_disable_interface() before usb_hcd_alloc_bandwidth() to ensure URBs are flushed before new ring buffers for the endpoints are allocated.
Otherwise host driver will attempt to find and remove old stale URBs from a freshly allocated new ringbuffer.
Cc: stable stable@kernel.org Fixes: 4fe0387afa89 ("USB: don't send Set-Interface after reset") Signed-off-by: Mathias Nyman mathias.nyman@linux.intel.com Link: https://lore.kernel.org/r/20250514132520.225345-1-mathias.nyman@linux.intel.... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/core/hub.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-)
--- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -6103,6 +6103,7 @@ static int usb_reset_and_verify_device(s struct usb_hub *parent_hub; struct usb_hcd *hcd = bus_to_hcd(udev->bus); struct usb_device_descriptor descriptor; + struct usb_interface *intf; struct usb_host_bos *bos; int i, j, ret = 0; int port1 = udev->portnum; @@ -6160,6 +6161,18 @@ static int usb_reset_and_verify_device(s if (!udev->actconfig) goto done;
+ /* + * Some devices can't handle setting default altsetting 0 with a + * Set-Interface request. Disable host-side endpoints of those + * interfaces here. Enable and reset them back after host has set + * its internal endpoint structures during usb_hcd_alloc_bandwith() + */ + for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { + intf = udev->actconfig->interface[i]; + if (intf->cur_altsetting->desc.bAlternateSetting == 0) + usb_disable_interface(udev, intf, true); + } + mutex_lock(hcd->bandwidth_mutex); ret = usb_hcd_alloc_bandwidth(udev, udev->actconfig, NULL, NULL); if (ret < 0) { @@ -6191,12 +6204,11 @@ static int usb_reset_and_verify_device(s */ for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { struct usb_host_config *config = udev->actconfig; - struct usb_interface *intf = config->interface[i]; struct usb_interface_descriptor *desc;
+ intf = config->interface[i]; desc = &intf->cur_altsetting->desc; if (desc->bAlternateSetting == 0) { - usb_disable_interface(udev, intf, true); usb_enable_interface(udev, intf, true); ret = 0; } else {