From owner-freebsd-i386@FreeBSD.ORG Thu Nov 18 14:10:27 2004 Return-Path: Delivered-To: freebsd-i386@hub.freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id DC52016A4CE for ; Thu, 18 Nov 2004 14:10:27 +0000 (GMT) Received: from freefall.freebsd.org (freefall.freebsd.org [216.136.204.21]) by mx1.FreeBSD.org (Postfix) with ESMTP id A8E7E43D53 for ; Thu, 18 Nov 2004 14:10:27 +0000 (GMT) (envelope-from gnats@FreeBSD.org) Received: from freefall.freebsd.org (gnats@localhost [127.0.0.1]) by freefall.freebsd.org (8.12.11/8.12.11) with ESMTP id iAIEARIg028664 for ; Thu, 18 Nov 2004 14:10:27 GMT (envelope-from gnats@freefall.freebsd.org) Received: (from gnats@localhost) by freefall.freebsd.org (8.12.11/8.12.11/Submit) id iAIEARVE028663; Thu, 18 Nov 2004 14:10:27 GMT (envelope-from gnats) Resent-Date: Thu, 18 Nov 2004 14:10:27 GMT Resent-Message-Id: <200411181410.iAIEARVE028663@freefall.freebsd.org> Resent-From: FreeBSD-gnats-submit@FreeBSD.org (GNATS Filer) Resent-To: freebsd-i386@FreeBSD.org Resent-Reply-To: FreeBSD-gnats-submit@FreeBSD.org, Arne Wörner Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id B8CCD16A4CE for ; Thu, 18 Nov 2004 14:05:51 +0000 (GMT) Received: from www.freebsd.org (www.freebsd.org [216.136.204.117]) by mx1.FreeBSD.org (Postfix) with ESMTP id A901643D5E for ; Thu, 18 Nov 2004 14:05:51 +0000 (GMT) (envelope-from nobody@FreeBSD.org) Received: from www.freebsd.org (localhost [127.0.0.1]) by www.freebsd.org (8.12.11/8.12.11) with ESMTP id iAIE5pmY053345 for ; Thu, 18 Nov 2004 14:05:51 GMT (envelope-from nobody@www.freebsd.org) Received: (from nobody@localhost) by www.freebsd.org (8.12.11/8.12.11/Submit) id iAIE5pqa053338; Thu, 18 Nov 2004 14:05:51 GMT (envelope-from nobody) Message-Id: <200411181405.iAIE5pqa053338@www.freebsd.org> Date: Thu, 18 Nov 2004 14:05:51 GMT From: Arne Wörner To: freebsd-gnats-submit@FreeBSD.org X-Send-Pr-Version: www-2.3 Subject: i386/74074: hw.ata.wc=0 / but write cache still enabled X-BeenThere: freebsd-i386@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: I386-specific issues for FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 18 Nov 2004 14:10:28 -0000 >Number: 74074 >Category: i386 >Synopsis: hw.ata.wc=0 / but write cache still enabled >Confidential: no >Severity: serious >Priority: medium >Responsible: freebsd-i386 >State: open >Quarter: >Keywords: >Date-Required: >Class: sw-bug >Submitter-Id: current-users >Arrival-Date: Thu Nov 18 14:10:27 GMT 2004 >Closed-Date: >Last-Modified: >Originator: Arne Wörner >Release: R5.3 >Organization: >Environment: FreeBSD neo.riddick.homeunix.org. 5.3-RELEASE FreeBSD 5.3-RELEASE #0: Thu Nov 11 17:27:53 UTC 2004 aw@neo.riddick.homeunix.org.:/usr/obj/usr/src/sys/RIDDICK i386 >Description: I wanted to turn of ATA disc write caching (by setting hw.ata.wc to zero): but after a boot after power on atacontrol cap 0 0 still says, that the write cache feature is enabled: write cache yes yes while sysctl says, that hw.ata.wc is 0: # sysctl hw.ata.wc hw.ata.wc: 0 I think this is a bug, that can be security relevant in the case of a power failure or system crash (at least if one is using a filesystem with soft updates enabled). After a reboot (warm) the write cache is sometimes disabled but sometimes enabled... :-( >How-To-Repeat: 1. shutdown the box 2. turn off power 3. turn on power 4. look at hw.ata.wc 5. look ata atacontrol's output >Fix: >Release-Note: >Audit-Trail: >Unformatted: