From owner-freebsd-hackers@FreeBSD.ORG Mon Aug 27 20:04:40 2012 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 076601065670 for ; Mon, 27 Aug 2012 20:04:40 +0000 (UTC) (envelope-from dieterbsd@engineer.com) Received: from mailout-us.gmx.com (mailout-us.gmx.com [74.208.5.67]) by mx1.freebsd.org (Postfix) with SMTP id A35758FC1A for ; Mon, 27 Aug 2012 20:04:39 +0000 (UTC) Received: (qmail 13637 invoked by uid 0); 27 Aug 2012 20:04:38 -0000 Received: from 67.206.186.222 by rms-us009 with HTTP Content-Type: text/plain; charset="utf-8" Date: Mon, 27 Aug 2012 16:04:37 -0400 From: "Dieter BSD" Message-ID: <20120827200438.165810@gmx.com> MIME-Version: 1.0 To: freebsd-hackers@freebsd.org X-Authenticated: #74169980 X-Flags: 0001 X-Mailer: GMX.com Web Mailer x-registered: 0 Content-Transfer-Encoding: 8bit X-GMX-UID: gbdJcKEh3zOlNR3dAHAhrj9+IGRvbwDq Subject: Re: How to diagnose system freezes? X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 27 Aug 2012 20:04:40 -0000 Yuri writes: > Anything else I can try? > > One thing of importance here is that there is an older graphics card > 9400 GT on this system and current nvidia-driver-295.71 has an issue > with 9400 GT: it makes graphics to malfunction (unpainted windows, long > delays switching to terminal mode) or freezes Xorg (but not OS). So I > run the older nvidia-driver-285.05.09 which appears to work. > That's why I think that nvidia driver is probably to blame for these > periodic OS freezes. Also the latest driver version must be, obviously, > working for most people because (I think) they mostly have newer than > mine nvidia cards. Have you found a way to trigger the bug on demand? Since you suspect the nvidia-driver-285.05.09, try some other driver, and do whatever triggers the bug and see if you get the freeze. > So maybe I should also just get the newer nvidia card > and shut up, not sure. If you can demonstrate that the various nvidia drivers are broken in various ways, submit a problem report to whoever wrote the drivers (Nvidia presumably). If Nvidia supports their products, then they will fix their drivers. If they don't support their products, why would you want to reward them by buying another nvidia card? But the question I have is: why are device drivers allowed to freeze the entire machine? I have at *least* 4 drivers that freeze the machine long enough for data to be lost. My theory is that: 1) An interrupt comes in. 2) ALL INTERRUPTS ARE BLOCKED ! 3) The device driver sits around too long. 4) Eventually the interrupts are turned back on. If the device driver gets stuck in an infinite loop, the machine hangs forever. Assuming my theory is correct (anyone disagree?), then WHY are ALL interrupts blocked? Why can't we just block interrupts for that particular device?