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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 86079C433EF for ; Tue, 19 Jun 2018 15:03:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3748C20661 for ; Tue, 19 Jun 2018 15:03:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3748C20661 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S937763AbeFSPDt (ORCPT ); Tue, 19 Jun 2018 11:03:49 -0400 Received: from mx2.suse.de ([195.135.220.15]:53582 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S937547AbeFSPDr (ORCPT ); Tue, 19 Jun 2018 11:03:47 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (charybdis-ext-too.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id D2AACAD98; Tue, 19 Jun 2018 15:03:44 +0000 (UTC) Subject: Re: [PATCH v5 0/3] extern inline native_save_fl for paravirt To: Nick Desaulniers , akpm@linux-foundation.org, hpa@zytor.com, mingo@redhat.com, tglx@linutronix.de Cc: linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, x86@kernel.org, virtualization@lists.linux-foundation.org, astrachan@google.com, manojgupta@google.com, ghackmann@google.com, sedat.dilek@gmail.com, tstellar@redhat.com, keescook@google.com, yamada.masahiro@socionext.com, michal.lkml@markovi.net, linux-kbuild@vger.kernel.org, geert@linux-m68k.org, will.deacon@arm.com, mawilcox@microsoft.com, arnd@arndb.de, rientjes@google.com, acme@redhat.com, pombredanne@nexb.com, aryabinin@virtuozzo.com, kstewart@linuxfoundation.org, boris.ostrovsky@oracle.com, jan.kiszka@siemens.com, rostedt@goodmis.org, kirill.shutemov@linux.intel.com, ard.biesheuvel@linaro.org, akataria@vmware.com, brijesh.singh@amd.com, caoj.fnst@cn.fujitsu.com, gregkh@linuxfoundation.org, jarkko.sakkinen@linux.intel.com, jpoimboe@redhat.com, mka@chromium.org, thomas.lendacky@amd.com, tweek@google.com, mjg59@google.com, joe@perches.com, andrea.parri@amarulasolutions.com References: <20180613210518.113983-1-ndesaulniers@google.com> From: Juergen Gross Openpgp: preference=signencrypt Autocrypt: addr=jgross@suse.com; prefer-encrypt=mutual; keydata= xsBNBFOMcBYBCACgGjqjoGvbEouQZw/ToiBg9W98AlM2QHV+iNHsEs7kxWhKMjrioyspZKOB ycWxw3ie3j9uvg9EOB3aN4xiTv4qbnGiTr3oJhkB1gsb6ToJQZ8uxGq2kaV2KL9650I1SJve dYm8Of8Zd621lSmoKOwlNClALZNew72NjJLEzTalU1OdT7/i1TXkH09XSSI8mEQ/ouNcMvIJ NwQpd369y9bfIhWUiVXEK7MlRgUG6MvIj6Y3Am/BBLUVbDa4+gmzDC9ezlZkTZG2t14zWPvx XP3FAp2pkW0xqG7/377qptDmrk42GlSKN4z76ELnLxussxc7I2hx18NUcbP8+uty4bMxABEB AAHNHkp1ZXJnZW4gR3Jvc3MgPGpncm9zc0BzdXNlLmRlPsLAeQQTAQIAIwUCU4xw6wIbAwcL CQgHAwIBBhUIAgkKCwQWAgMBAh4BAheAAAoJELDendYovxMvi4UH/Ri+OXlObzqMANruTd4N zmVBAZgx1VW6jLc8JZjQuJPSsd/a+bNr3BZeLV6lu4Pf1Yl2Log129EX1KWYiFFvPbIiq5M5 kOXTO8Eas4CaScCvAZ9jCMQCgK3pFqYgirwTgfwnPtxFxO/F3ZcS8jovza5khkSKL9JGq8Nk czDTruQ/oy0WUHdUr9uwEfiD9yPFOGqp4S6cISuzBMvaAiC5YGdUGXuPZKXLpnGSjkZswUzY d9BVSitRL5ldsQCg6GhDoEAeIhUC4SQnT9SOWkoDOSFRXZ+7+WIBGLiWMd+yKDdRG5RyP/8f 3tgGiB6cyuYfPDRGsELGjUaTUq3H2xZgIPfOwE0EU4xwFgEIAMsx+gDjgzAY4H1hPVXgoLK8 B93sTQFN9oC6tsb46VpxyLPfJ3T1A6Z6MVkLoCejKTJ3K9MUsBZhxIJ0hIyvzwI6aYJsnOew cCiCN7FeKJ/oA1RSUemPGUcIJwQuZlTOiY0OcQ5PFkV5YxMUX1F/aTYXROXgTmSaw0aC1Jpo w7Ss1mg4SIP/tR88/d1+HwkJDVW1RSxC1PWzGizwRv8eauImGdpNnseneO2BNWRXTJumAWDD pYxpGSsGHXuZXTPZqOOZpsHtInFyi5KRHSFyk2Xigzvh3b9WqhbgHHHE4PUVw0I5sIQt8hJq 5nH5dPqz4ITtCL9zjiJsExHuHKN3NZsAEQEAAcLAXwQYAQIACQUCU4xwFgIbDAAKCRCw3p3W KL8TL0P4B/9YWver5uD/y/m0KScK2f3Z3mXJhME23vGBbMNlfwbr+meDMrJZ950CuWWnQ+d+ Ahe0w1X7e3wuLVODzjcReQ/v7b4JD3wwHxe+88tgB9byc0NXzlPJWBaWV01yB2/uefVKryAf AHYEd0gCRhx7eESgNBe3+YqWAQawunMlycsqKa09dBDL1PFRosF708ic9346GLHRc6Vj5SRA UTHnQqLetIOXZm3a2eQ1gpQK9MmruO86Vo93p39bS1mqnLLspVrL4rhoyhsOyh0Hd28QCzpJ wKeHTd0MAWAirmewHXWPco8p1Wg+V+5xfZzuQY0f4tQxvOpXpt4gQ1817GQ5/Ed/wsDtBBgB CAAgFiEEhRJncuj2BJSl0Jf3sN6d1ii/Ey8FAlrd8NACGwIAgQkQsN6d1ii/Ey92IAQZFggA HRYhBFMtsHpB9jjzHji4HoBcYbtP2GO+BQJa3fDQAAoJEIBcYbtP2GO+TYsA/30H/0V6cr/W V+J/FCayg6uNtm3MJLo4rE+o4sdpjjsGAQCooqffpgA+luTT13YZNV62hAnCLKXH9n3+ZAgJ RtAyDWk1B/0SMDVs1wxufMkKC3Q/1D3BYIvBlrTVKdBYXPxngcRoqV2J77lscEvkLNUGsu/z W2pf7+P3mWWlrPMJdlbax00vevyBeqtqNKjHstHatgMZ2W0CFC4hJ3YEetuRBURYPiGzuJXU pAd7a7BdsqWC4o+GTm5tnGrCyD+4gfDSpkOT53S/GNO07YkPkm/8J4OBoFfgSaCnQ1izwgJQ jIpcG2fPCI2/hxf2oqXPYbKr1v4Z1wthmoyUgGN0LPTIm+B5vdY82wI5qe9uN6UOGyTH2B3p hRQUWqCwu2sqkI3LLbTdrnyDZaixT2T0f4tyF5Lfs+Ha8xVMhIyzNb1byDI5FKCb Message-ID: <6a36db0d-e790-48d6-183a-263c355531b6@suse.com> Date: Tue, 19 Jun 2018 17:03:26 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: <20180613210518.113983-1-ndesaulniers@google.com> Content-Type: text/plain; charset=utf-8 Content-Language: de-DE Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 13/06/18 23:05, Nick Desaulniers wrote: > paravirt depends on a custom calling convention (callee saved), but > expects this from a static inline function that it then forces to be > outlined. This is problematic because different compilers or flags can > then add a stack guard that violates the calling conventions. > > Uses extern inline with the out-of-line definition in assembly to > prevent compilers from adding stack guards to the outlined version. > > Other parts of the codebase overwrite KBUILD_CFLAGS, which is *extremely > problematic* for extern inline, as the sematics are completely the > opposite depending on what C standard is used. > http://blahg.josefsipek.net/?p=529 > > Changes since v4: > Take Arnd's and hpa's suggestions properly feature detect gnu_inline > attribute to support gcc 4.1. > > Changes since v3: > Take Joe's suggestion to hoist __inline__ and __inline out of > conditional block. > > Changes since v2: > Take hpa's _ASM_ARG patch into the set in order to simplify cross > 32b/64b x86 assembly and rebase my final patch to use it. Apply > Sedat's typo fix to commit message and sign off on it. Take Joe's > suggestion to simplify __inline__ and __inline. Add Arnd to list of > folks who made helpful suggestions. > > Changes since v1: > Prefer gnu_inline function attribute instead of explicitly setting C > standard compiler flag in problematic Makefiles. We should instead > carefully evaluate if those Makefiles should be overwriting > KBUILD_CFLAGS at all. Dropped the previous first two patches and added > a new first patch. > > H. Peter Anvin (1): > x86/asm: add _ASM_ARG* constants for argument registers to > > Nick Desaulniers (2): > compiler-gcc.h: add gnu_inline to all inline declarations > x86: paravirt: make native_save_fl extern inline > > arch/x86/include/asm/asm.h | 59 +++++++++++++++++++++++++++++++++ > arch/x86/include/asm/irqflags.h | 2 +- > arch/x86/kernel/Makefile | 1 + > arch/x86/kernel/irqflags.S | 26 +++++++++++++++ > include/linux/compiler-gcc.h | 29 ++++++++++++---- > 5 files changed, 109 insertions(+), 8 deletions(-) > create mode 100644 arch/x86/kernel/irqflags.S > For the series: Acked-by: Juergen Gross Juergen