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=-8.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_GIT 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 9A3DCC070C3 for ; Mon, 15 Oct 2018 00:37:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3DEC12086A for ; Mon, 15 Oct 2018 00:37:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="bjWSTInf" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3DEC12086A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.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 S1726497AbeJOIUj (ORCPT ); Mon, 15 Oct 2018 04:20:39 -0400 Received: from mail-pg1-f193.google.com ([209.85.215.193]:40193 "EHLO mail-pg1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726186AbeJOIUj (ORCPT ); Mon, 15 Oct 2018 04:20:39 -0400 Received: by mail-pg1-f193.google.com with SMTP id n31-v6so8304930pgm.7 for ; Sun, 14 Oct 2018 17:37:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=b/Xhw2EK4mi+d59RNeXlr73INQgb0338IFEVhaRhBVU=; b=bjWSTInflpJ4vXSG1gpGc3EsEluf5+so9hwwcTwCMK/MJZeZjmCfYcnd0YfeExuyRG lCa2st5Zp1NKjHcBqOMrutc15brV5iq8VJ2PtxPjXAawxffRIThJWqsnJWP6vmrC0ait HS6nESbTlhrnp430Sx+qx6JzD8UxeDJ85hSPBtuO4JB8Vuc5dnFJF8nql/JX57ovDlDT tsL1XAECbl5AilWYka10aweSTWBlTijoHnUSmqrQdPzmIeIGdH+vj39WZ4hy3mxuOQFg cRGxnHE/J3kaWFuLIJNIpKuiqXrU4SEIZI04wFv3z4XLbrauveynBrgfu/tUXz8bdAKm n9mQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=b/Xhw2EK4mi+d59RNeXlr73INQgb0338IFEVhaRhBVU=; b=jmwieVPuThnWMN2C6kVWffjHn8EWWj/JDve3P0EoFAjsesKWuaG5sRJKC5Qi8SnYmN VYAyJofo2fPMgzvEn3N3R98YCuYgCNddOlazX6dXDTc0/WtDbmkWGne4uJ5GYUtFV2A/ qPkAKy2dpgIjw47M+VfAFO1q/bSWZosg5Sj9i8VEWsxKhHI8ynE0u5rJU/1zUFEtSCNo FywCnnlEBD5ho7Klz5JCofdMplZykvHKxTwf8o5ocsJlotPQ/kMCzJr1sgQLvKMccM6r 8DZd5RCGa6Akv9XO69EngFVbRaZs/xnIdKdV/3JDLrGuNGklPce2zQcI/q2TSlui0MyU er1w== X-Gm-Message-State: ABuFfoho1yx3jZPulSDiGuFwecb8T1nKA5Nrif5OzWAxV9EZ6l+XLZEy 7fAkHaSxCTx2xkJ28ZLaXbI= X-Google-Smtp-Source: ACcGV60pdp+BL3SB8DimSZAAUgoTMSsWgQOXimAzocDiP8drsr9gIpcdwlSNm2zd+t1acZVlod9FOQ== X-Received: by 2002:a62:5b43:: with SMTP id p64-v6mr15673839pfb.122.1539563867666; Sun, 14 Oct 2018 17:37:47 -0700 (PDT) Received: from localhost.localdomain (50-197-184-177-static.hfc.comcastbusiness.net. [50.197.184.177]) by smtp.googlemail.com with ESMTPSA id x15-v6sm15489920pfd.27.2018.10.14.17.37.46 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 14 Oct 2018 17:37:46 -0700 (PDT) From: Nick Desaulniers To: dave.hansen@linux.intel.com, luto@kernel.org, peterz@infradead.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, hpa@zytor.com Cc: natechancellor@gmail.com, Nick Desaulniers , x86@kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] x86/mm: annotate no_context with UNWIND_HINTS Date: Sun, 14 Oct 2018 17:37:26 -0700 Message-Id: <20181015003726.29103-1-nick.desaulniers@gmail.com> X-Mailer: git-send-email 2.17.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Fixes the objtool warning: arch/x86/mm/fault.o: warning: objtool: no_context()+0x220: unreachable instruction Link: https://github.com/ClangBuiltLinux/linux/issues/204 Signed-off-by: Nick Desaulniers --- arch/x86/mm/fault.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 47bebfe6efa7..057d2178fa19 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -760,9 +760,11 @@ no_context(struct pt_regs *regs, unsigned long error_code, * and then double-fault, though, because we're likely to * break the console driver and lose most of the stack dump. */ - asm volatile ("movq %[stack], %%rsp\n\t" + asm volatile (UNWIND_HINT_SAVE + "movq %[stack], %%rsp\n\t" "call handle_stack_overflow\n\t" - "1: jmp 1b" + "1: jmp 1b\n\t" + UNWIND_HINT_RESTORE : ASM_CALL_CONSTRAINT : "D" ("kernel stack overflow (page fault)"), "S" (regs), "d" (address), -- 2.17.1