xhci: Do not use GFP_KERNEL in (potentially) atomic context

BugLink: https://bugs.launchpad.net/bugs/1931292
commit dda32c00c9a0fa103b5d54ef72c477b7aa993679 upstream.

'xhci_urb_enqueue()' is passed a 'mem_flags' argument, because "URBs may be
submitted in interrupt context" (see comment related to 'usb_submit_urb()'
in 'drivers/usb/core/urb.c')

So this flag should be used in all the calling chain.
Up to now, 'xhci_check_maxpacket()' which is only called from
'xhci_urb_enqueue()', uses GFP_KERNEL.

Be safe and pass the mem_flags to this function as well.

Fixes: ddba5cd0aeff ("xhci: Use command structures when queuing commands on the command ring")
Cc: <stable@vger.kernel.org>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20210512080816.866037-4-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 66147f9179e5943d778bdf78ef3f29e8cb7aa870..e81f4175e2ebcc3ace07ebd433f68dd4dab6b27c 100644 (file)
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -1523,7 +1523,7 @@ static int xhci_configure_endpoint(struct xhci_hcd *xhci,
  * we need to issue an evaluate context command and wait on it.
  */
 static int xhci_check_maxpacket(struct xhci_hcd *xhci, unsigned int slot_id,
-               unsigned int ep_index, struct urb *urb)
+               unsigned int ep_index, struct urb *urb, gfp_t mem_flags)
 {
        struct xhci_container_ctx *out_ctx;
        struct xhci_input_control_ctx *ctrl_ctx;
@@ -1554,7 +1554,7 @@ static int xhci_check_maxpacket(struct xhci_hcd *xhci, unsigned int slot_id,
                 * changes max packet sizes.
                 */
 
-               command = xhci_alloc_command(xhci, true, GFP_KERNEL);
+               command = xhci_alloc_command(xhci, true, mem_flags);
                if (!command)
                        return -ENOMEM;
 
@@ -1648,7 +1648,7 @@ static int xhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flag
                 */
                if (urb->dev->speed == USB_SPEED_FULL) {
                        ret = xhci_check_maxpacket(xhci, slot_id,
-                                       ep_index, urb);
+                                       ep_index, urb, mem_flags);
                        if (ret < 0) {
                                xhci_urb_free_priv(urb_priv);
                                urb->hcpriv = NULL;