From owner-freebsd-usb@FreeBSD.ORG Sun Mar 13 21:20:06 2005 Return-Path: Delivered-To: freebsd-usb@hub.freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 3EDF016A4CE for ; Sun, 13 Mar 2005 21:20:06 +0000 (GMT) Received: from freefall.freebsd.org (freefall.freebsd.org [216.136.204.21]) by mx1.FreeBSD.org (Postfix) with ESMTP id 1E69243D3F for ; Sun, 13 Mar 2005 21:20:06 +0000 (GMT) (envelope-from gnats@FreeBSD.org) Received: from freefall.freebsd.org (gnats@localhost [127.0.0.1]) by freefall.freebsd.org (8.13.3/8.13.3) with ESMTP id j2DLK5Fc066479 for ; Sun, 13 Mar 2005 21:20:06 GMT (envelope-from gnats@freefall.freebsd.org) Received: (from gnats@localhost) by freefall.freebsd.org (8.13.3/8.13.1/Submit) id j2DLK5j0066478; Sun, 13 Mar 2005 21:20:05 GMT (envelope-from gnats) Date: Sun, 13 Mar 2005 21:20:05 GMT Message-Id: <200503132120.j2DLK5j0066478@freefall.freebsd.org> To: freebsd-usb@FreeBSD.org From: Ian Dowse Subject: Re: usb/78208: ulpt page fault X-BeenThere: freebsd-usb@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list Reply-To: Ian Dowse List-Id: FreeBSD support for USB List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 13 Mar 2005 21:20:06 -0000 The following reply was made to PR usb/78208; it has been noted by GNATS. From: Ian Dowse To: Jan-Espen Pettersen Cc: FreeBSD-gnats-submit@FreeBSD.org Subject: Re: usb/78208: ulpt page fault Date: Sun, 13 Mar 2005 21:14:58 +0000 In message <200502281829.j1SIT6sb003645@endeavour.localnet.radiotube.org>, Jan- Espen Pettersen writes: >>Description: >I got this page fault trap just after printing via ulpt. The pages came out ju >st fine, which is why I think this problem is about handling EOF or close of t >ransaction with /dev/ulpt0. To me this looks like a timer (as the name *_tick) > which probably was not stopped in time, and therefore didn't have a valid xfe >r pointer to pass to the setup routine. These crashes has been going on for a >while, but I haven't been able to get crashdumps before recently when I starte >d to press Ctrl+Alt+F1 shortly after starting the print jobs. This looks like it could be caused by a known race condition in kernel timers. Is the problem easy to reproduce for you? If so, could you try the patch at http://people.freebsd.org/~iedowse/releng_5_callout.diff and see if it helps? Remove your patch to ulpt.c first. The above patch is a partial backport of some changes that went in to -CURRENT that fix some race conditions with Giant-locked kernel timers. Ian