Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932278AbWJTQhO (ORCPT ); Fri, 20 Oct 2006 12:37:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S2992630AbWJTQhO (ORCPT ); Fri, 20 Oct 2006 12:37:14 -0400 Received: from smtp.osdl.org ([65.172.181.4]:4756 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S932278AbWJTQhM (ORCPT ); Fri, 20 Oct 2006 12:37:12 -0400 Date: Fri, 20 Oct 2006 09:36:57 -0700 (PDT) From: Linus Torvalds To: Nick Piggin cc: David Miller , ralf@linux-mips.org, akpm@osdl.org, linux-kernel@vger.kernel.org, anemo@mba.ocn.ne.jp Subject: Re: [PATCH 1/3] Fix COW D-cache aliasing on fork In-Reply-To: <4538F1EC.1020806@yahoo.com.au> Message-ID: References: <1161275748231-git-send-email-ralf@linux-mips.org> <4537B9FB.7050303@yahoo.com.au> <20061019181346.GA5421@linux-mips.org> <20061019.155939.48528489.davem@davemloft.net> <4538DFAC.1090206@yahoo.com.au> <4538F1EC.1020806@yahoo.com.au> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 816 Lines: 22 On Sat, 21 Oct 2006, Nick Piggin wrote: > > I didn't think that would work if there is no TLB. But if the writeback > can cause a TLB reload, and then bypass the readonly protection, then > yes would close all races. On the other hand, doing the cache flush at COW time is "kind of equivalent" to just doing it after the TLB flush. It's now just _much_ after the flush ;) So maybe the COW D$ aliasing patch-series is just the right thing to do. Not worry about D$ at _all_ when doing the actual fork, and only worry about it on an actual COW event. Hmm? Linus - 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/