Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

xhci: Use GFP_NOIO during device reset.

Browse source 
When xhci_discover_or_reset_device() is called after a host controller
power loss, the virtual device may need to be reallocated.  Make sure
xhci_alloc_dev() uses GFP_NOIO.  This avoid causing a deadlock by allowing
the kernel to flush pending I/O while reallocating memory for a virtual
device for a USB mass storage device that's holding the backing store for
dirty memory buffers.

This patch should be queued for the 2.6.37 stable tree.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@kernel.org
This commit is contained in:
Sarah Sharp 2010-12-28 13:08:42 -08:00
parent 653a39d1f6
commit a6d940dd75
1 changed files with 6 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

8
drivers/usb/host/xhci.c
View file

@ -2431,8 +2431,12 @@ int xhci_alloc_dev(struct usb_hcd *hcd, struct usb_device *udev)
xhci_err(xhci, "Error while assigning device slot ID\n");
return 0;
}
/* xhci_alloc_virt_device() does not touch rings; no need to lock */
if (!xhci_alloc_virt_device(xhci, xhci->slot_id, udev, GFP_KERNEL)) {
/* xhci_alloc_virt_device() does not touch rings; no need to lock.
* Use GFP_NOIO, since this function can be called from
* xhci_discover_or_reset_device(), which may be called as part of
* mass storage driver error handling.
*/
if (!xhci_alloc_virt_device(xhci, xhci->slot_id, udev, GFP_NOIO)) {
/* Disable slot, if we can do it without mem alloc */
xhci_warn(xhci, "Could not allocate xHCI USB device data structures\n");
spin_lock_irqsave(&xhci->lock, flags);