From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263995AbUEXFkx (ORCPT ); Mon, 24 May 2004 01:40:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263980AbUEXFkx (ORCPT ); Mon, 24 May 2004 01:40:53 -0400 Received: from gate.crashing.org ([63.228.1.57]:47585 "EHLO gate.crashing.org") by vger.kernel.org with ESMTP id S263995AbUEXFj4 (ORCPT ); Mon, 24 May 2004 01:39:56 -0400 Subject: Re: [PATCH] ppc64: Fix possible race with set_pte on a present PTE From: Benjamin Herrenschmidt To: Linus Torvalds Cc: Andrew Morton , Linux Kernel list , Ingo Molnar , Ben LaHaise , linux-mm@kvack.org In-Reply-To: <1085376888.24948.45.camel@gaston> References: <1085369393.15315.28.camel@gaston> <1085371988.15281.38.camel@gaston> <1085373839.14969.42.camel@gaston> <1085376888.24948.45.camel@gaston> Content-Type: text/plain Message-Id: <1085377091.15281.49.camel@gaston> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.6 Date: Mon, 24 May 2004 15:38:12 +1000 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > Well, the original scenario triggering that from userland is, imho, so > broken, that we may just not care losing that dirty bit ... Oh well :) > Anyway, apply my patch. If pte is not present, this will have no effect, > if it is, it makes sure we never leave a stale HPTE in the hash, which > is fatal in far worse ways. Hrm... Or maybe I should just do in set_pte something like BUG_ON(pte_present(ptep)) That would make me sleep better ;) Ben.