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=-13.5 required=3.0 tests=FROM_EXCESS_BASE64, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_2 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 3E89CC4CEC7 for ; Thu, 12 Sep 2019 20:19:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1337C20830 for ; Thu, 12 Sep 2019 20:19:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726748AbfILUTv convert rfc822-to-8bit (ORCPT ); Thu, 12 Sep 2019 16:19:51 -0400 Received: from mx2.suse.de ([195.135.220.15]:60688 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726099AbfILUTv (ORCPT ); Thu, 12 Sep 2019 16:19:51 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 31F95AD08; Thu, 12 Sep 2019 20:19:48 +0000 (UTC) Date: Thu, 12 Sep 2019 22:19:46 +0200 From: Michal =?UTF-8?B?U3VjaMOhbmVr?= To: Christophe Leroy Cc: Madhavan Srinivasan , David Hildenbrand , Heiko Carstens , Paul Mackerras , Breno Leitao , Michael Neuling , Diana Craciun , Firoz Khan , Joel Stanley , Arnd Bergmann , Nicholas Piggin , Alexander Viro , Thomas Gleixner , Allison Randal , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, Hari Bathini , "Eric W. Biederman" , Andrew Donnellan , linux-fsdevel@vger.kernel.org, Andrew Morton , linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH v8 5/7] powerpc/64: make buildable without CONFIG_COMPAT Message-ID: <20190912221946.41a161e4@kitsune.suse.cz> In-Reply-To: <758324b9-203b-ec4b-affc-a30aefc9ea23@c-s.fr> References: <039ed7ac686927fe169241ac72225a258d95ccfc.1568306311.git.msuchanek@suse.de> <9973bf6b-f1b9-c778-bd88-ed41e45ca126@c-s.fr> <20190912202604.14a73423@kitsune.suse.cz> <758324b9-203b-ec4b-affc-a30aefc9ea23@c-s.fr> Organization: SUSE Linux X-Mailer: Claws Mail 3.17.1 (GTK+ 2.24.32; x86_64-suse-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 12 Sep 2019 21:36:11 +0200 Christophe Leroy wrote: > Le 12/09/2019 à 20:26, Michal Suchánek a écrit : > > On Thu, 12 Sep 2019 20:02:16 +0200 > > Christophe Leroy wrote: > > > >> Le 12/09/2019 à 19:26, Michal Suchanek a écrit : > >>> There are numerous references to 32bit functions in generic and 64bit > >>> code so ifdef them out. > >>> > >>> Signed-off-by: Michal Suchanek > >>> --- > >>> v2: > >>> - fix 32bit ifdef condition in signal.c > >>> - simplify the compat ifdef condition in vdso.c - 64bit is redundant > >>> - simplify the compat ifdef condition in callchain.c - 64bit is redundant > >>> v3: > >>> - use IS_ENABLED and maybe_unused where possible > >>> - do not ifdef declarations > >>> - clean up Makefile > >>> v4: > >>> - further makefile cleanup > >>> - simplify is_32bit_task conditions > >>> - avoid ifdef in condition by using return > >>> v5: > >>> - avoid unreachable code on 32bit > >>> - make is_current_64bit constant on !COMPAT > >>> - add stub perf_callchain_user_32 to avoid some ifdefs > >>> v6: > >>> - consolidate current_is_64bit > >>> v7: > >>> - remove leftover perf_callchain_user_32 stub from previous series version > >>> v8: > >>> - fix build again - too trigger-happy with stub removal > >>> - remove a vdso.c hunk that causes warning according to kbuild test robot > >>> --- > >>> arch/powerpc/include/asm/thread_info.h | 4 +-- > >>> arch/powerpc/kernel/Makefile | 7 ++--- > >>> arch/powerpc/kernel/entry_64.S | 2 ++ > >>> arch/powerpc/kernel/signal.c | 3 +- > >>> arch/powerpc/kernel/syscall_64.c | 6 ++-- > >>> arch/powerpc/kernel/vdso.c | 3 +- > >>> arch/powerpc/perf/callchain.c | 39 ++++++++++++++------------ > >>> 7 files changed, 33 insertions(+), 31 deletions(-) > >>> > >>> diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h > >>> index 8e1d0195ac36..c128d8a48ea3 100644 > >>> --- a/arch/powerpc/include/asm/thread_info.h > >>> +++ b/arch/powerpc/include/asm/thread_info.h > >>> @@ -144,10 +144,10 @@ static inline bool test_thread_local_flags(unsigned int flags) > >>> return (ti->local_flags & flags) != 0; > >>> } > >>> > >>> -#ifdef CONFIG_PPC64 > >>> +#ifdef CONFIG_COMPAT > >>> #define is_32bit_task() (test_thread_flag(TIF_32BIT)) > >>> #else > >>> -#define is_32bit_task() (1) > >>> +#define is_32bit_task() (IS_ENABLED(CONFIG_PPC32)) > >>> #endif > >>> > >>> #if defined(CONFIG_PPC64) > >> > >> [...] > >> > >>> +static inline int current_is_64bit(void) > >>> +{ > >>> + if (!IS_ENABLED(CONFIG_COMPAT)) > >>> + return IS_ENABLED(CONFIG_PPC64); > >>> + /* > >>> + * We can't use test_thread_flag() here because we may be on an > >>> + * interrupt stack, and the thread flags don't get copied over > >>> + * from the thread_info on the main stack to the interrupt stack. > >>> + */ > >>> + return !test_ti_thread_flag(task_thread_info(current), TIF_32BIT); > >>> +} > >> > >> > >> Since at least commit ed1cd6deb013 ("powerpc: Activate > >> CONFIG_THREAD_INFO_IN_TASK") > >> [https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ed1cd6d] > >> the above comment is wrong and current_is_64bit() is equivalent to > >> !is_32bit_task() > >> > >> See https://github.com/linuxppc/issues/issues/275 > >> > >> Christophe > > > > I aim at changing the code as little as possible here. A separate patch > > on top removing this function would be ok? > > Yes I agree. By making prior to this patch a separate patch which drops > current_is_64bit() would be good. And it would reduce the size of this > patch by approximately one third. Indeed, removing it before makes this patch much cleaner. Thanks Michal