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 30965CD8CAC for ; Tue, 10 Oct 2023 17:48:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233780AbjJJRsn (ORCPT ); Tue, 10 Oct 2023 13:48:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57730 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231130AbjJJRsl (ORCPT ); Tue, 10 Oct 2023 13:48:41 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E8CBD99 for ; Tue, 10 Oct 2023 10:48:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; 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=m7DQWBMz8yLU63XLUakLZSqJHmYw8jWnqgK8hjlHCfw=; b=OtehqaCgzj8JHUVLeIgT20tOws TAH65SYQlbthMPK0xK9AaonDMcE2tYOliylEjtUZSOGEVJdLNVP603y3DFr2BTWDGgHRvFXGirdvw nxRNfhjJ/l9AOGdkRfKJA+bOixvgm2TS399aSCe0D5U176kLRAzDRfT/jWXlb3XLAUSnOoUzWCWXU CaBEWO3nuJ0sYkE59uTkl5w4iIXP5B6sixr91j+01i/wv5NznyyIRktZA+iiVFVjDO19HtFsN8gfF 8d6MjUQuwLGINQgvPvg/HcENpg230aRGVziLIPfKpQ4/WKpj6C1KHOcoLXU7DmRKdNNmWsihEuVsp dWsRnZMw==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1qqGqQ-005wuc-5r; Tue, 10 Oct 2023 17:48:34 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id D2FD4300392; Tue, 10 Oct 2023 19:48:33 +0200 (CEST) Date: Tue, 10 Oct 2023 19:48:33 +0200 From: Peter Zijlstra To: David Kaplan Cc: x86@kernel.org, luto@kernel.org, linux-kernel@vger.kernel.org, Josh Poimboeuf Subject: Re: [PATCH 1/3] Revert "x86/retpoline: Remove .text..__x86.return_thunk section" Message-ID: <20231010174833.GG14330@noisy.programming.kicks-ass.net> References: <20231010171020.462211-1-david.kaplan@amd.com> <20231010171020.462211-2-david.kaplan@amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20231010171020.462211-2-david.kaplan@amd.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Oct 10, 2023 at 12:10:18PM -0500, David Kaplan wrote: > arch/x86/kernel/vmlinux.lds.S | 3 +++ > arch/x86/lib/retpoline.S | 2 ++ > 2 files changed, 5 insertions(+) > > diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S > index 9cdb1a7332c4..54a5596adaa6 100644 > --- a/arch/x86/kernel/vmlinux.lds.S > +++ b/arch/x86/kernel/vmlinux.lds.S > @@ -132,7 +132,10 @@ SECTIONS > LOCK_TEXT > KPROBES_TEXT > SOFTIRQENTRY_TEXT > +#ifdef CONFIG_RETPOLINE > *(.text..__x86.indirect_thunk) > + *(.text..__x86.return_thunk) > +#endif > STATIC_CALL_TEXT > > ALIGN_ENTRY_TEXT_BEGIN > diff --git a/arch/x86/lib/retpoline.S b/arch/x86/lib/retpoline.S > index db813113e637..3da768a71cf9 100644 > --- a/arch/x86/lib/retpoline.S > +++ b/arch/x86/lib/retpoline.S > @@ -129,6 +129,8 @@ SYM_CODE_END(__x86_indirect_jump_thunk_array) > > #ifdef CONFIG_RETHUNK Perhaps elucidate the future reader with a comment here? Lest someone tries removing it again. > > + .section .text..__x86.return_thunk > + > #ifdef CONFIG_CPU_SRSO