From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 877CDC433EF for ; Wed, 20 Apr 2022 15:51:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1379757AbiDTPyQ (ORCPT ); Wed, 20 Apr 2022 11:54:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33182 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232903AbiDTPyO (ORCPT ); Wed, 20 Apr 2022 11:54:14 -0400 Received: from desiato.infradead.org (desiato.infradead.org [IPv6:2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 339C03FDB4 for ; Wed, 20 Apr 2022 08:51:28 -0700 (PDT) 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=64YXxcekbBcHuR/pr9BA25gJNm0zvp5b2EChe5V7YSU=; b=MrsvalZVr0CQIT6szVIkkuWZ4A TbpXqRendCyaA6KlLbK+GDCq2k1ScDQXQq85oaFOgFLLk0HSnvHDaqAx0ThJ8XOpxMhqAl8EXEKNu vq78Lrx4DbuWOgKVsdADM2ObhI23B+arlKunYymzdTH9lieMoTI3o1zh3dF7A3DnPkdbDJsSJ2cQm OZ/mJhvJjyc/ojyxfpANiU5Ele6k1U5UDIR5tx/eq6D8ZyPeDwjU0gIkI3buKSWI5pi95q5IiyJBZ IPD9oH2IAb/UP6lZ4iPvySK5tzjenuDFDWZH+Mbb4r16gOjxmmVzVh4UpZe+9aFERtEGsYGzREmVA Na2Yezfg==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=worktop.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nhCbu-0079ps-2e; Wed, 20 Apr 2022 15:51:18 +0000 Received: by worktop.programming.kicks-ass.net (Postfix, from userid 1000) id 6BC109861A4; Wed, 20 Apr 2022 17:51:16 +0200 (CEST) Date: Wed, 20 Apr 2022 17:51:16 +0200 From: Peter Zijlstra To: Josh Poimboeuf Cc: x86@kernel.org, brgerst@gmail.com, jiangshanlai@gmail.com, Andrew.Cooper3@citrix.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] x86: Simplify Retpoline thunk Message-ID: <20220420155116.GH2731@worktop.programming.kicks-ass.net> References: <20220419204109.520779286@infradead.org> <20220419205241.280037046@infradead.org> <20220420152736.qzl3nikds6mq5nrr@treble> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220420152736.qzl3nikds6mq5nrr@treble> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 20, 2022 at 08:27:36AM -0700, Josh Poimboeuf wrote: > On Tue, Apr 19, 2022 at 10:41:10PM +0200, Peter Zijlstra wrote: > > Now that we rewrite all the indirect call sites, per commit: > > > > 750850090081 ("x86/alternative: Implement .retpoline_sites support") > > > > it doesn't make sense to have the retpoline thunks be an ALTERNATIVE_2 > > that still includes a 'naked' indirect jump. > > > > (this accidentally 'defunnels' i386 by going back to full retpolines) > > So mitigations=off no longer works on i386? Also true I suppose... does anybody care? /me runs like heck. I'd hate to make all this more complicated just because i386 tho :/