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=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 56033CA9EA0 for ; Fri, 18 Oct 2019 16:11:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 26BDE22466 for ; Fri, 18 Oct 2019 16:11:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="RTWmB+YR" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2442957AbfJRQLF (ORCPT ); Fri, 18 Oct 2019 12:11:05 -0400 Received: from mail-vs1-f73.google.com ([209.85.217.73]:47476 "EHLO mail-vs1-f73.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2442937AbfJRQLD (ORCPT ); Fri, 18 Oct 2019 12:11:03 -0400 Received: by mail-vs1-f73.google.com with SMTP id r26so1566823vsq.14 for ; Fri, 18 Oct 2019 09:11:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=soVi6argGh8CkyJ/tZS/XQoN8aAv6F/7ncnrrIAGrbI=; b=RTWmB+YRhbyTrupTegTePDqh83wahNiLo24V/vkd3XNh2/VjRfOzsP8l9UA07iBYVh cNCOrmz1KApedjuZfTuf+oEAy7uJ9vOjlPpxsg7OkJReg5LlWaNnJSadKKQxT6uV8oo9 DYHGRvWBz3/GUdtlA0wIAJuRmYFSW5vXFhnZ39LEFxcVI9DqpO8eIN9kDWvp9NjS8BGy xN5pkbK5dusYfEE++LF7k5cNY+Cu1x/v4ps1Ft2zcALY7q2NKOD2KsdADykKFGjX/ek9 pgnN2RfC3QCLk3Iaa8HyaKxHiBf6citZAP2zBGFrT6GXMyCWAMsRsDGnPTlW+RbabIhg vExA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=soVi6argGh8CkyJ/tZS/XQoN8aAv6F/7ncnrrIAGrbI=; b=fzmkheGA7ta/bA4L4nyFJeMhCP2jGDqdw084+96IHN+nSqSEXsMYU3RNJvvwdnUv16 YU3DUp0AwYOTc5XBxKc4oIiA+iABk7+OefUgsclHzMJGwleUqwMrq+P1tPOC34IiK4nQ vvCbl1FMLrLJKcB01ltUwOXVJN9g5RJDtMFh6CxUB53jomqN6mA/bD0Jqd5HYOEtWf9/ gpgXaTjvZCSoGybGkprdvtCXZKEjBxPN659CWOSrK6BtKxgnHojA6xQvP0GL4oBLfSpX VKC6Co4ejXesMN07lvoK+4aNBfbqhLHOSVgTLDZa7aiWrMcARHHA16um8goaZF7SvOjd h2Fg== X-Gm-Message-State: APjAAAUNuJgVIxOyO4TA8OtUi8mB5xybtq0n0G1ShRQYW4wzH/3wWsqG wswO1q1QaHDXMOZlhO7VX//aElekpvMjz8M9S6A= X-Google-Smtp-Source: APXvYqzkAvflPUA4hxOT5c7IqsE0Ybkf3fYa0ytmTSeu2hOJz51kZPeU6sdMsbUTLU2Tls8gLg9QkcQsftcMtRZzrhY= X-Received: by 2002:a67:e34b:: with SMTP id s11mr5965401vsm.195.1571415062790; Fri, 18 Oct 2019 09:11:02 -0700 (PDT) Date: Fri, 18 Oct 2019 09:10:20 -0700 In-Reply-To: <20191018161033.261971-1-samitolvanen@google.com> Message-Id: <20191018161033.261971-6-samitolvanen@google.com> Mime-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> X-Mailer: git-send-email 2.23.0.866.gb869b98d4c-goog Subject: [PATCH 05/18] arm64: kbuild: reserve reg x18 from general allocation by the compiler From: Sami Tolvanen To: Will Deacon , Catalin Marinas , Steven Rostedt , Ard Biesheuvel Cc: Dave Martin , Kees Cook , Laura Abbott , Mark Rutland , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Sami Tolvanen 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 From: Ard Biesheuvel Before we can start using register x18 for a special purpose (as permitted by the AAPCS64 ABI), we need to tell the compiler that it is off limits for general allocation. So tag it as 'fixed', and remove the mention from the LL/SC compiler flag override. Link: https://patchwork.kernel.org/patch/9836881/ Signed-off-by: Ard Biesheuvel Signed-off-by: Sami Tolvanen --- arch/arm64/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile index 2c0238ce0551..1c7b276bc7c5 100644 --- a/arch/arm64/Makefile +++ b/arch/arm64/Makefile @@ -55,7 +55,7 @@ endif KBUILD_CFLAGS += -mgeneral-regs-only $(lseinstr) $(brokengasinst) \ $(compat_vdso) $(cc_has_k_constraint) -KBUILD_CFLAGS += -fno-asynchronous-unwind-tables +KBUILD_CFLAGS += -fno-asynchronous-unwind-tables -ffixed-x18 KBUILD_CFLAGS += $(call cc-disable-warning, psabi) KBUILD_AFLAGS += $(lseinstr) $(brokengasinst) $(compat_vdso) -- 2.23.0.866.gb869b98d4c-goog