[MODERATED] [PATCH v6 39/43] MDSv6

[Andi Kleen <andi@firstfloor.org>]

Most USB interrupt handlers do not touch user data, except
in some cases hcd poll is called which can copy a user buffer.
Instead of marking all the USB interrupts and timers as clear cpu
only clear it when the user data touching actually happens.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
---
 drivers/usb/core/hcd.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 015b126ce455..be47f96e810d 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -29,6 +29,7 @@
 #include <linux/workqueue.h>
 #include <linux/pm_runtime.h>
 #include <linux/types.h>
+#include <linux/clearcpu.h>
 
 #include <linux/phy/phy.h>
 #include <linux/usb.h>
@@ -770,6 +771,8 @@ void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
 			urb->actual_length = length;
 			memcpy(urb->transfer_buffer, buffer, length);
 
+			lazy_clear_cpu_interrupt();
+
 			usb_hcd_unlink_urb_from_ep(hcd, urb);
 			usb_hcd_giveback_urb(hcd, urb, 0);
 		} else {
-- 
2.17.2