Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757898AbZGGOIR (ORCPT ); Tue, 7 Jul 2009 10:08:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756287AbZGGOIA (ORCPT ); Tue, 7 Jul 2009 10:08:00 -0400 Received: from smtp-out003.kontent.com ([81.88.40.217]:36590 "EHLO smtp-out003.kontent.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755259AbZGGOH7 (ORCPT ); Tue, 7 Jul 2009 10:07:59 -0400 From: Oliver Neukum To: Jiri Kosina Subject: Re: Null Pointer BUG in uhci_hcd Date: Tue, 7 Jul 2009 16:08:10 +0200 User-Agent: KMail/1.10.3 (Linux/2.6.30-0.1-default; KDE/4.1.3; x86_64; ; ) Cc: "Michael S. Zick" , linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org References: <200907051720.45819.lkml@morethan.org> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200907071608.11050.oliver@neukum.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1507 Lines: 54 Am Dienstag, 7. Juli 2009 11:13:01 schrieb Jiri Kosina: > [ adding linux-usb to CC ] > > On Sun, 5 Jul 2009, Michael S. Zick wrote: > > Anyone with suggestions about this one? Looks like we should test for presence before we switch off autosuspend for khubd. Please test this diagnostic patch if this is repeatable. Regards Oliver diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 2af3b4f..c5b3929 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -371,11 +371,16 @@ static void kick_khubd(struct usb_hub *hub) { unsigned long flags; - /* Suppress autosuspend until khubd runs */ - to_usb_interface(hub->intfdev)->pm_usage_cnt = 1; + if (!hub) { + BUG(); + return; + } spin_lock_irqsave(&hub_event_lock, flags); if (!hub->disconnected && list_empty(&hub->event_list)) { + /* Suppress autosuspend until khubd runs */ + to_usb_interface(hub->intfdev)->pm_usage_cnt = 1; + list_add_tail(&hub->event_list, &hub_event_list); wake_up(&khubd_wait); } @@ -384,6 +389,11 @@ static void kick_khubd(struct usb_hub *hub) void usb_kick_khubd(struct usb_device *hdev) { + if (!hdev) { + BUG(); + return; + } + /* FIXME: What if hdev isn't bound to the hub driver? */ kick_khubd(hdev_to_hub(hdev)); } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/