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=-14.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, 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 4AD44C433DB for ; Thu, 21 Jan 2021 20:38:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0ABF52389F for ; Thu, 21 Jan 2021 20:38:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727318AbhAUUiI (ORCPT ); Thu, 21 Jan 2021 15:38:08 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50826 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727864AbhAUHuN (ORCPT ); Thu, 21 Jan 2021 02:50:13 -0500 Received: from mail-ed1-x52f.google.com (mail-ed1-x52f.google.com [IPv6:2a00:1450:4864:20::52f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E4991C0613C1; Wed, 20 Jan 2021 23:49:32 -0800 (PST) Received: by mail-ed1-x52f.google.com with SMTP id g24so1284908edw.9; Wed, 20 Jan 2021 23:49:32 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=n0kVyilkbftdlhrZGBzYXl+bMHX+Nzyhy+1J+qK9jjI=; b=fv3ivvntYxxPUhrJb3+zPJxO8OIJuhpnp9BZ7IMLgLKd7i0n80zEGOlQePgYYjWbU9 44MmOi9vxggwQ9j6BAo27frRmyI6koeynqELS9CCAeXeOp/DVbkuu1HOdKET49ELVadr 8Pt9ngTFvf9hHBouOyg45MkXl+XhujYr2j7vd1JiyF4Ml8eZ1qO42xr9D/EKUhaA36F7 Ho66gRxB/g/cdSgXgHE0SwO5PVQnPX4Ca9sg7Karft29NtUjz7eDTa9m/ey1ApivI9lD EoeymaoX1B6l6UPfM6yl0Qq/T+da4RzVQh9YFZt7I94ZUO1cvLkLV0Qc8Qt4qLZGQPEw CEvQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=n0kVyilkbftdlhrZGBzYXl+bMHX+Nzyhy+1J+qK9jjI=; b=Yc+g0eevkSSs+Tmw4srzCnBReEInBuKzqthkSqG02T3ddtB7vLFvln/RPnLUQl822q ycqMurdMR7QGnDsuxE+6AJHUkca6YE6qquPFpvIwrf0cgFh35u3bOwoM/AZ3k5dOgYI2 yU1RSryLT6Gi7uY4xCyxb6Juk3jFgdp6GLxakfVD2KH3t+cpkQQPUkkUc+zr2BF7lq6+ 9Uyrrkfvxmyyygo1Z6ucbKnczCW+LCBfKhaTRUDAC/vJ93veZiEDCs20th6uuunTWD7j pB6SyeZ99vkwOZeSjR5dQxLzKF2Grmb2yiNbELwFdo7v2tnMA0+K7pHUjYR+DR6as8Te u/eA== X-Gm-Message-State: AOAM531y8yQhYPkeUoMJZtVX+yuff93b90vHWmsuQmodXCrDcIvgtdgP DndY90/EVP9LEpB6lvnAgL1qX2dbMHk= X-Google-Smtp-Source: ABdhPJxkJJ8mCPvmxZOt0+ncQM1iIBTaVCp6iEK8CWEH+NfAjrAuyOjerE6XoqZKGigy6eZEGeGLPA== X-Received: by 2002:a05:6402:1549:: with SMTP id p9mr10319164edx.387.1611215371583; Wed, 20 Jan 2021 23:49:31 -0800 (PST) Received: from gmail.com (20014C4E1C877B00F0D36816790CCC7F.dsl.pool.telekom.hu. [2001:4c4e:1c87:7b00:f0d3:6816:790c:cc7f]) by smtp.gmail.com with ESMTPSA id u23sm2276091edt.78.2021.01.20.23.49.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Jan 2021 23:49:30 -0800 (PST) Sender: Ingo Molnar Date: Thu, 21 Jan 2021 08:49:28 +0100 From: Ingo Molnar To: linux-kernel@vger.kernel.org Cc: linux-tip-commits@vger.kernel.org, Andrea Righi , Borislav Petkov , x86@kernel.org Subject: Re: [tip: x86/entry] x86/entry: Build thunk_$(BITS) only if CONFIG_PREEMPTION=y Message-ID: <20210121074928.GA1346795@gmail.com> References: <161121327995.414.14890124942899525500.tip-bot2@tip-bot2> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <161121327995.414.14890124942899525500.tip-bot2@tip-bot2> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * tip-bot2 for Andrea Righi wrote: > The following commit has been merged into the x86/entry branch of tip: > > Commit-ID: e6d92b6680371ae1aeeb6c5eb2387fdc5d9a2c89 > Gitweb: https://git.kernel.org/tip/e6d92b6680371ae1aeeb6c5eb2387fdc5d9a2c89 > Author: Andrea Righi > AuthorDate: Thu, 14 Jan 2021 12:48:35 +01:00 > Committer: Ingo Molnar > CommitterDate: Thu, 21 Jan 2021 08:11:52 +01:00 > > x86/entry: Build thunk_$(BITS) only if CONFIG_PREEMPTION=y > > With CONFIG_PREEMPTION disabled, arch/x86/entry/thunk_64.o is just an > empty object file. > > With the newer binutils (tested with 2.35.90.20210113-1ubuntu1) the GNU > assembler doesn't generate a symbol table for empty object files and > objtool fails with the following error when a valid symbol table cannot > be found: > > arch/x86/entry/thunk_64.o: warning: objtool: missing symbol table > > To prevent this from happening, build thunk_$(BITS).o only if > CONFIG_PREEMPTION is enabled. > > BugLink: https://bugs.launchpad.net/bugs/1911359 > > Fixes: 320100a5ffe5 ("x86/entry: Remove the TRACE_IRQS cruft") > Signed-off-by: Andrea Righi > Signed-off-by: Ingo Molnar > Cc: Borislav Petkov > Link: https://lore.kernel.org/r/YAAvk0UQelq0Ae7+@xps-13-7390 Hm, this fails to build on UML defconfig: /home/mingo/gcc/cross/lib/gcc/x86_64-linux/9.3.1/../../../../x86_64-linux/bin/ld: arch/x86/um/../entry/thunk_64.o: in function `preempt_schedule_thunk': /home/mingo/tip.cross/arch/x86/um/../entry/thunk_64.S:34: undefined reference to `preempt_schedule' /home/mingo/gcc/cross/lib/gcc/x86_64-linux/9.3.1/../../../../x86_64-linux/bin/ld: arch/x86/um/../entry/thunk_64.o: in function `preempt_schedule_notrace_thunk': /home/mingo/tip.cross/arch/x86/um/../entry/thunk_64.S:35: undefined reference to `preempt_schedule_notrace' Thanks, Ingo