From: Alan Stern <stern@rowland.harvard.edu>
Date: Tue, 11 Dec 2007 21:02:23 +0000 (-0500)
Subject: USB: fix locking loop by avoiding flush_scheduled_work
X-Git-Tag: v2.6.24-rc6~60^2~4
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d48bd977e0dd8c17081d12242bfc09d743ea0d26;p=linux-2.6

USB: fix locking loop by avoiding flush_scheduled_work

This patch (as1027) replaces a call to flush_scheduled_work() -- a
dangerous routine to invoke, especially while holding any sort of lock
-- with calls to cancel_work_sync() and cancel_delayed_work_sync().

This fixes Bugzilla #9532.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: David Brownell <david-b@pacbell.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 13b326a133..b04d232d4c 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -522,9 +522,9 @@ static void hub_quiesce(struct usb_hub *hub)
 	/* (blocking) stop khubd and related activity */
 	usb_kill_urb(hub->urb);
 	if (hub->has_indicators)
-		cancel_delayed_work(&hub->leds);
-	if (hub->has_indicators || hub->tt.hub)
-		flush_scheduled_work();
+		cancel_delayed_work_sync(&hub->leds);
+	if (hub->tt.hub)
+		cancel_work_sync(&hub->tt.kevent);
 }
 
 static void hub_activate(struct usb_hub *hub)