Commit 8829057f authored May 12, 2021 by Christophe JAILLET Committed by Greg Kroah-Hartman May 22, 2021

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



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: ddba5cd0 ("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


[iwamatsu: Adjust context]
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent de327b40

drivers/usb/host/xhci.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -1309,7 +1309,7 @@ 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;
		@@ -1340,7 +1340,7 @@ static int xhci_check_maxpacket(struct xhci_hcd *xhci, unsigned int slot_id,
		* changes max packet sizes.
		*/

		command = xhci_alloc_command(xhci, false, true, GFP_KERNEL);
		command = xhci_alloc_command(xhci, false, true, mem_flags);
		if (!command)
		return -ENOMEM;

		@@ -1447,7 +1447,7 @@ int xhci_urb_enqueue(struct usb_hcd hcd, struct urb urb, gfp_t mem_flags)
		*/
		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;