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=-22.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 57FD2CA9ECB for ; Thu, 31 Oct 2019 19:47:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1B0D1208C0 for ; Thu, 31 Oct 2019 19:47:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="o+caVVGF" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729656AbfJaTrF (ORCPT ); Thu, 31 Oct 2019 15:47:05 -0400 Received: from mail-ua1-f74.google.com ([209.85.222.74]:34688 "EHLO mail-ua1-f74.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727667AbfJaTrF (ORCPT ); Thu, 31 Oct 2019 15:47:05 -0400 Received: by mail-ua1-f74.google.com with SMTP id d22so1375947ual.1 for ; Thu, 31 Oct 2019 12:47:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=mRTJzqi2Ekt/Yu6tImUxgj9kbqR+IWI4OvQzXYofR00=; b=o+caVVGFnJaE5mAgvlQks4Vt9WfRP5nPUg+5+Hr5H23VB74dEbBUvLWtnx5ukYsLuQ uJnHTX/0giXOn5XGbO1SWDm9RHpNQs1kXIZvDQaxkAhLJhnNkP+E1/GerwLMgguovtH5 fljcFhGwDi7EJU81lzjMjyMGYP/MwD7apkHAR327pQK+abQpiNjIgUThEiSOjbTyHbsZ 6zbj6smVIRQIuDsZC+mpkQ1bCElwZSK014y7Wjxik1ylEvZlkwDZjbHdqPKRuzEXT/IA VXyNTjLUKXtmsy5WcEspU+zgyCMY3NGcg1dZtX7etpTHuT/vE0zM6+dqJyF6AULhkhET IdVw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=mRTJzqi2Ekt/Yu6tImUxgj9kbqR+IWI4OvQzXYofR00=; b=P1ljh80zKREN3e8GZFQPYpkZswcZQykHnHBczYnNmL5mD4WrSb5jXVBGU91/W6gjeQ 04wQQAQtu4orOTDOLDuOplSkr4XMKwmnhKlk8lG/fu76BWG8XfOsdT4pqY0tRchznDQj J33gjr+DSef4ZknCpXIufJgk42JipVQip2pVxsuOtSiPmNoBaM5X2Kw5Qs7kH+KYodqU gCz7YmjYfbCqLcHArfLn+E7EeCv4+4wT3osuUffnznyRc9hJ+5nXWPjBYKvqXZWwH5l5 IR9RxqrT79L4EfyJMVPhS2G+MTegb78JLhdawCaSAU3OlRGNi4dWEEOyqUi8iiOCIgU7 x1nw== X-Gm-Message-State: APjAAAX07rhuwcuu5Hz311Op7TcReoi8njsL9bE4H9u4Or97PDYZD3fB BxWcRBtE5i4HvRx8cqOKx7VvY4xpnggT18i+26k= X-Google-Smtp-Source: APXvYqxzqMbKO2P0RiotkL+tykifzgNeUhGA6MD6WbnPJ+rbijXzJlYgYAoB8+RbcMWACIXROHcgmNmnX/OygX1b+AU= X-Received: by 2002:a67:fe86:: with SMTP id b6mr3761803vsr.162.1572551222774; Thu, 31 Oct 2019 12:47:02 -0700 (PDT) Date: Thu, 31 Oct 2019 12:46:52 -0700 Message-Id: <20191031194652.118427-1-samitolvanen@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.24.0.rc0.303.g954a862665-goog Subject: [RESEND PATCH] arm64: fix alternatives with LLVM's integrated assembler From: Sami Tolvanen To: Catalin Marinas , Will Deacon , Marc Zyngier Cc: Kees Cook , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Sami Tolvanen , Nick Desaulniers Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org LLVM's integrated assembler fails with the following error when building KVM: :12:6: error: expected absolute expression .if kvm_update_va_mask == 0 ^ :21:6: error: expected absolute expression .if kvm_update_va_mask == 0 ^ :24:2: error: unrecognized instruction mnemonic NOT_AN_INSTRUCTION ^ LLVM ERROR: Error parsing inline asm These errors come from ALTERNATIVE_CB and __ALTERNATIVE_CFG, which test for the existence of the callback parameter in inline assembly using the following expression: " .if " __stringify(cb) " == 0\n" This works with GNU as, but isn't supported by LLVM. This change splits __ALTERNATIVE_CFG and ALTINSTR_ENTRY into separate macros to fix the LLVM build. Link: https://github.com/ClangBuiltLinux/linux/issues/472 Signed-off-by: Sami Tolvanen Tested-by: Nick Desaulniers --- arch/arm64/include/asm/alternative.h | 32 ++++++++++++++++++---------- 1 file changed, 21 insertions(+), 11 deletions(-) diff --git a/arch/arm64/include/asm/alternative.h b/arch/arm64/include/asm/alternative.h index b9f8d787eea9..324e7d5ab37e 100644 --- a/arch/arm64/include/asm/alternative.h +++ b/arch/arm64/include/asm/alternative.h @@ -35,13 +35,16 @@ void apply_alternatives_module(void *start, size_t length); static inline void apply_alternatives_module(void *start, size_t length) { } #endif -#define ALTINSTR_ENTRY(feature,cb) \ +#define ALTINSTR_ENTRY(feature) \ " .word 661b - .\n" /* label */ \ - " .if " __stringify(cb) " == 0\n" \ " .word 663f - .\n" /* new instruction */ \ - " .else\n" \ + " .hword " __stringify(feature) "\n" /* feature bit */ \ + " .byte 662b-661b\n" /* source len */ \ + " .byte 664f-663f\n" /* replacement len */ + +#define ALTINSTR_ENTRY_CB(feature, cb) \ + " .word 661b - .\n" /* label */ \ " .word " __stringify(cb) "- .\n" /* callback */ \ - " .endif\n" \ " .hword " __stringify(feature) "\n" /* feature bit */ \ " .byte 662b-661b\n" /* source len */ \ " .byte 664f-663f\n" /* replacement len */ @@ -62,15 +65,14 @@ static inline void apply_alternatives_module(void *start, size_t length) { } * * Alternatives with callbacks do not generate replacement instructions. */ -#define __ALTERNATIVE_CFG(oldinstr, newinstr, feature, cfg_enabled, cb) \ +#define __ALTERNATIVE_CFG(oldinstr, newinstr, feature, cfg_enabled) \ ".if "__stringify(cfg_enabled)" == 1\n" \ "661:\n\t" \ oldinstr "\n" \ "662:\n" \ ".pushsection .altinstructions,\"a\"\n" \ - ALTINSTR_ENTRY(feature,cb) \ + ALTINSTR_ENTRY(feature) \ ".popsection\n" \ - " .if " __stringify(cb) " == 0\n" \ ".pushsection .altinstr_replacement, \"a\"\n" \ "663:\n\t" \ newinstr "\n" \ @@ -78,17 +80,25 @@ static inline void apply_alternatives_module(void *start, size_t length) { } ".popsection\n\t" \ ".org . - (664b-663b) + (662b-661b)\n\t" \ ".org . - (662b-661b) + (664b-663b)\n" \ - ".else\n\t" \ + ".endif\n" + +#define __ALTERNATIVE_CFG_CB(oldinstr, feature, cfg_enabled, cb) \ + ".if "__stringify(cfg_enabled)" == 1\n" \ + "661:\n\t" \ + oldinstr "\n" \ + "662:\n" \ + ".pushsection .altinstructions,\"a\"\n" \ + ALTINSTR_ENTRY_CB(feature, cb) \ + ".popsection\n" \ "663:\n\t" \ "664:\n\t" \ - ".endif\n" \ ".endif\n" #define _ALTERNATIVE_CFG(oldinstr, newinstr, feature, cfg, ...) \ - __ALTERNATIVE_CFG(oldinstr, newinstr, feature, IS_ENABLED(cfg), 0) + __ALTERNATIVE_CFG(oldinstr, newinstr, feature, IS_ENABLED(cfg)) #define ALTERNATIVE_CB(oldinstr, cb) \ - __ALTERNATIVE_CFG(oldinstr, "NOT_AN_INSTRUCTION", ARM64_CB_PATCH, 1, cb) + __ALTERNATIVE_CFG_CB(oldinstr, ARM64_CB_PATCH, 1, cb) #else #include -- 2.24.0.rc0.303.g954a862665-goog