From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 458EE2063E8 for ; Sat, 22 Feb 2025 12:25:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740227151; cv=none; b=W7wkTQXXbEbW7YatXE4pwvsFEcawP16U1iF5iQ5mjb631VoLPvNXun/8QwhprTNARwDqBkQTwV5qr+qK7fPtmwNfmHyoO2B1FzjSLdCf7Dz3QoM4mReehjqJCf1K+upA3iUeOGV/B7GKgGQWfESABEOaw7CuAZWZz6aRyojErj0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740227151; c=relaxed/simple; bh=wFPOZGTzQtXqzaUsuG5YhWC9eGVsW6AClawQBeA9UEg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Nln5X5JKk8NAjS4V7AJcqSuNi8Vqmtu21seqn3ZgBbnTCV9V4YCnzp2cBiLTCx3JS3GRsa62UCkJRO+smAgD8fuAR0SF1lyQ21m2Xojvd0ge9ckWCO53thUscE9S+O71YXoGHNddxJR5zJrPzZO/XMGUaWGCbEB6x8zDTC29P2k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=BErU0CRg; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="BErU0CRg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CD1F9C4CED1; Sat, 22 Feb 2025 12:25:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1740227150; bh=wFPOZGTzQtXqzaUsuG5YhWC9eGVsW6AClawQBeA9UEg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=BErU0CRgEYCV5hl0SNKFbr9+gfHXGtHCdQqgiPZ1hHi+tTDTXjab8KKw9y8FMaodl ohtHcpGO1M8cFedTMKT7t0eXo/qXsD7zLnwjk2sJ+tVe5DONTmZY1PgARHNBnS5BdZ i9bQqNYXs1JRMBwof0UAjgEPaRcIhCoBojk+kGGINWcW3nFsruXjBVg49ZPGrJZH28 IIP0zNT2ZaxA5cFPio/jdxNK8oWgkhcO7dJsjxQsx/zx1+KUDgIAyLS3PqBkXRrNmR RI5eunM1ACDAGz2FE17QO2qvF1Ywvy1GqKRSX7Zbm7Juccvk/Jye+TyAMq5kOxwmcU zpEfGoBGEXBrA== Date: Sat, 22 Feb 2025 13:25:40 +0100 From: Ingo Molnar To: Brian Gerst Cc: Uros Bizjak , linux-kernel@vger.kernel.org, x86@kernel.org, "H . Peter Anvin" , Thomas Gleixner , Borislav Petkov , Ard Biesheuvel Subject: Re: [PATCH v6 00/15] x86-64: Stack protector and percpu improvements Message-ID: References: <20250123190747.745588-1-brgerst@gmail.com> 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=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: * Brian Gerst wrote: > On Thu, Feb 20, 2025 at 8:26 AM Ingo Molnar wrote: > > > > > > * Brian Gerst wrote: > > > > > On Wed, Feb 19, 2025 at 6:47 AM Ingo Molnar wrote: > > > > > > > > > > > > * Uros Bizjak wrote: > > > > > > > > > > Thank you for doing this series - it all looks pretty good from my > > > > > > side and I've applied it experimentally to tip:x86/asm. I fixed up > > > > > > the trivial details other reviewers and me noticed. > > > > > > > > > > > > Note that the merge is tentative, it might still need a rebase if > > > > > > some fundamental problem comes up - but let's see how testing goes > > > > > > in -next. > > > > > > > > > > I wonder if there would be any benefit if stack canary is put into > > > > > struct pcpu_hot? > > > > > > > > It should definitely be one of the hottest data structures on x86, so > > > > moving it there makes sense even if it cannot be measured explicitly. > > > > > > > > > > It would have to be done with linker tricks, since you can't make the > > > compiler use a struct member directly. > > > > Probably not worth it then? > > Actually it wasn't so bad since we already had the hack for > __ref_stack_chk_guard. Do you want the patches now or when the dust > settles on the original series? We can add it now I suppose, while memories are fresh and all that. Thanks, Ingo