From bf3d7d40e42a85ca73a34e1385ff34f092a384eb Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Wed, 2 Feb 2011 13:59:33 -0500 Subject: [PATCH] USB: fix race between root-hub resume and wakeup requests The USB core keeps track of pending resume requests for root hubs, in order to resolve races between wakeup requests and suspends. However the code that does this is subject to another race (between wakeup requests and resumes) because the WAKEUP_PENDING flag is cleared before the resume occurs, leaving a window in which another wakeup request might arrive. This patch (as1447) fixes the problem by clearing the WAKEUP_PENDING flag after the resume instead of before it. This fixes Bugzilla #24952. Signed-off-by: Alan Stern Tested-by: Paul Bender Tested-by: warpme Cc: stable [.36+] Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/hcd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index 6a95017fa62b..e935f71d7a34 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -1955,7 +1955,6 @@ int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg) dev_dbg(&rhdev->dev, "usb %s%s\n", (msg.event & PM_EVENT_AUTO ? "auto-" : ""), "resume"); - clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags); if (!hcd->driver->bus_resume) return -ENOENT; if (hcd->state == HC_STATE_RUNNING) @@ -1963,6 +1962,7 @@ int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg) hcd->state = HC_STATE_RESUMING; status = hcd->driver->bus_resume(hcd); + clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags); if (status == 0) { /* TRSMRCY = 10 msec */ msleep(10);