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=-8.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 CE686C433E0 for ; Fri, 29 May 2020 04:24:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B200C20C56 for ; Fri, 29 May 2020 04:24:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728213AbgE2EY2 (ORCPT ); Fri, 29 May 2020 00:24:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59422 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727913AbgE2EYW (ORCPT ); Fri, 29 May 2020 00:24:22 -0400 Received: from ozlabs.org (ozlabs.org [IPv6:2401:3900:2:1::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BF4F6C08C5C6 for ; Thu, 28 May 2020 21:24:21 -0700 (PDT) Received: by ozlabs.org (Postfix, from userid 1034) id 49YBKY13Szz9sT4; Fri, 29 May 2020 14:24:16 +1000 (AEST) X-powerpc-patch-notification: thanks X-powerpc-patch-commit: 334710b1496af8a0960e70121f850e209c20958f In-Reply-To: <23e680624680a9a5405f4b88740d2596d4b17c26.1587143308.git.christophe.leroy@c-s.fr> To: Christophe Leroy , Benjamin Herrenschmidt , Paul Mackerras , npiggin@gmail.com, segher@kernel.crashing.org From: Michael Ellerman Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 1/2] powerpc/uaccess: Implement unsafe_put_user() using 'asm goto' Message-Id: <49YBKY13Szz9sT4@ozlabs.org> Date: Fri, 29 May 2020 14:24:16 +1000 (AEST) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2020-04-17 at 17:08:51 UTC, Christophe Leroy wrote: > unsafe_put_user() is designed to take benefit of 'asm goto'. > > Instead of using the standard __put_user() approach and branch > based on the returned error, use 'asm goto' and make the > exception code branch directly to the error label. There is > no code anymore in the fixup section. > > This change significantly simplifies functions using > unsafe_put_user() ... > > Signed-off-by: Christophe Leroy > Reviewed-by: Segher Boessenkool Applied to powerpc topic/uaccess-ppc, thanks. https://git.kernel.org/powerpc/c/334710b1496af8a0960e70121f850e209c20958f cheers