From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5A8A816D4C0 for ; Wed, 31 Jul 2024 21:26:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722461189; cv=none; b=UOwnVVrGU++vxbYKyOC2xw6ByoLyTe1LESlVNXzzwIHnvclM376tRg6l1lSoPRsHOheMqd/GB537xr2fWJgeX0o5xzp7EshwELgyjmrpR8lzAH7lQja1H27Jc1c27FpJ4HMzAuFmZxvGmlvhVx88u756rGhvC/KTW0Wz2JcAvHU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722461189; c=relaxed/simple; bh=jssOBMtwefVTqQ5mDVZIxmCimLUmPAjHIr4iA1/JjvQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=QvUHEmHsTjxga9PxbVyPA8ux0pkxP49WWvsBBXwidXO+QD3N6YJVMVhELMcVhFVYHmum1wKZ5YC73sxPOrx2wTZ2gosrRHlh1jLpy5UTP3NkL/HFRuftaV3PMe314D+AGVpKAD7mYHSs01wT6COVw+isFyC9p7o/JF9ODxw4pQ4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=enzRL0mX; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="enzRL0mX" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=7UantihI0biLHmzOvhvLs1/a48/spgItsd+twM2z2/0=; b=enzRL0mXkgpNjUgKm7+SDC5/21 GWSPepLIkSm3kBuTH7M3LPA9T6ggrQrxYc5xDlYwFP5U4QuPX0Q8iodARXZThQ6TK23CCKA/IVW1T bBOxdMdDnVgI0VpGy28kVxWgjU6p00637GXIuUkV8bf+ZnHOeX/285W47STmomb3m6mDauTZstrpy AWe/MNx27kiWdpyoM8WkgCvvDbuo0t8+QnJMnUd93iGRMvlMJQXbj0/UJJrBY1rfZFP0qFO1qVGzS 4oFIKXDKqpY/yfuAjK8kK1WOGvo0P8FItJRiP4K8wNHrmC7f/0xK8FAo75UWrNyxDPyzr4bpO3ct4 AJ/v41WQ==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.97.1 #2 (Red Hat Linux)) id 1sZGq0-00000005IQ2-2K6m; Wed, 31 Jul 2024 21:26:25 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 311C1300820; Wed, 31 Jul 2024 23:26:24 +0200 (CEST) Date: Wed, 31 Jul 2024 23:26:24 +0200 From: Peter Zijlstra To: Linus Torvalds Cc: Thomas Gleixner , Guenter Roeck , Jens Axboe , Andy Lutomirski , Ingo Molnar , Peter Anvin , Linux Kernel Mailing List , the arch/x86 maintainers Subject: Re: Linux 6.11-rc1 Message-ID: <20240731212624.GZ40213@noisy.programming.kicks-ass.net> References: <20240731122002.GE33588@noisy.programming.kicks-ass.net> <87mslx67dm.ffs@tglx> <20240731155551.GF33588@noisy.programming.kicks-ass.net> <20240731163105.GG33588@noisy.programming.kicks-ass.net> <20240731165108.GH33588@noisy.programming.kicks-ass.net> <87bk2d5v83.ffs@tglx> <20240731212007.GW26599@noisy.programming.kicks-ass.net> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Jul 31, 2024 at 02:23:02PM -0700, Linus Torvalds wrote: > On Wed, 31 Jul 2024 at 14:20, Peter Zijlstra wrote: > > > > The alternative is ripping that level thing out entirely, and simply > > duplicate anything we find in the page-tables. > > That looks clean to me, and don't we want to clone the minimal range > anyway - even on x86-64? x86_64 has everything PMD aligned. It *should* never encounter a PTE. Also, this thing blindly clones the format the kernel page-tables have, it will not split a PMD into multiple PTE entries just to clone a smaller range. It is super simple.