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 X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 58532C432BE for ; Fri, 27 Aug 2021 13:22:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3B83C60E93 for ; Fri, 27 Aug 2021 13:22:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245366AbhH0NXc (ORCPT ); Fri, 27 Aug 2021 09:23:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33096 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245356AbhH0NXW (ORCPT ); Fri, 27 Aug 2021 09:23:22 -0400 Received: from ozlabs.org (bilbo.ozlabs.org [IPv6:2401:3900:2:1::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7E6B9C0611FA for ; Fri, 27 Aug 2021 06:22:05 -0700 (PDT) Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4Gx0k16fKwz9sWl; Fri, 27 Aug 2021 23:22:01 +1000 (AEST) From: Michael Ellerman To: Michael Ellerman , Christophe Leroy , Paul Mackerras , Benjamin Herrenschmidt Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org In-Reply-To: <91b1d242525307ceceec7ef6e832bfbacdd4501b.1629436472.git.christophe.leroy@csgroup.eu> References: <91b1d242525307ceceec7ef6e832bfbacdd4501b.1629436472.git.christophe.leroy@csgroup.eu> Subject: Re: [PATCH] powerpc/32: indirect function call use bctrl rather than blrl in ret_from_kernel_thread Message-Id: <163007015584.52768.11072289865515594442.b4-ty@ellerman.id.au> Date: Fri, 27 Aug 2021 23:15:55 +1000 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 20 Aug 2021 05:16:05 +0000 (UTC), Christophe Leroy wrote: > Copied from commit 89bbe4c798bc ("powerpc/64: indirect function call > use bctrl rather than blrl in ret_from_kernel_thread") > > blrl is not recommended to use as an indirect function call, as it may > corrupt the link stack predictor. > > This is not a performance critical path but this should be fixed for > consistency. > > [...] Applied to powerpc/next. [1/1] powerpc/32: indirect function call use bctrl rather than blrl in ret_from_kernel_thread https://git.kernel.org/powerpc/c/113ec9ccc8049c3772f0eab46b62c5d6654c09f7 cheers