From patchwork Tue Sep 29 21:46:30 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11807143 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id F2CE313B2 for ; Tue, 29 Sep 2020 21:48:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C978A20789 for ; Tue, 29 Sep 2020 21:48:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="jWS8iUHI" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728272AbgI2Vsr (ORCPT ); Tue, 29 Sep 2020 17:48:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48414 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728206AbgI2Vsj (ORCPT ); Tue, 29 Sep 2020 17:48:39 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9F0EEC0613AA for ; Tue, 29 Sep 2020 14:47:38 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id e2so6356688ybc.17 for ; Tue, 29 Sep 2020 14:47:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=YnFARiKS6UDkwdk7WP0wlvbxlnuyKDZd5kTTgvwZzNo=; b=jWS8iUHI1yEZwlx3KeKvcgfGPXNdJ4L5onYlC3CBBL8D7obZFD5GHWOijlDtJb8Ij7 nRmkWkJefVtEgGfyFLejApsO2VFmeAT9vQpKzbQWErmeV2XzN2V7GUaE7Pe9GHYQRqUr Xv61qqqbIr/UD4HQGH+NeCWqUBIaeXjzSEj5haCz3bHxBeyeFilgtE7h3SBO5qI9TeFI VNBOjzf+qN4PzKeK/ip+sm+V/3xF7iAcrvnH3Y+OXfQISp+lvRlaGKxv9Vs2X9cKIOs1 +Egn3AASlwiipmUBXQC2SS1FvIyAuimNGXi91NcEG22l5xpotuSePeSMxIwf0qHe6n0r 39pg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=YnFARiKS6UDkwdk7WP0wlvbxlnuyKDZd5kTTgvwZzNo=; b=DHO9Wu4livByHzGRPOJk7oGlknOLCgu1+PLOWOVUrjknaa1siLzBY1T26PzV8yeBp7 NvGqDpdctJoprmQi28aPelU8YQJzGBr2Cs+MgsVZeep1naTv4QtUKKrzptq+wJbL0r6p /0KWrRLBZMb/EABdhiUJO5v/NPa49/+P8LTS/iQOS6NRbzIU+zpMg+xk6QO/v601YKs0 G4he9ylaRpobXTPcM8iI7lNpVhIpu985e37VNz7S0khjwMy4hsYrcUT2FYqNMP3LAHe+ +4meyr5GjPz1TSEq3dst/i/bpPT56zZ79ul+AOR/SrizZ/zfip05EL6BURsfL4uVl00g Nocg== X-Gm-Message-State: AOAM533E/QjdV71+jGnNYm7kB5sy3hv3c99vC0oNHuJpsYFr12azd/18 iKEZah3yXev2YQ/MdgaDaiGO1iCmRL8iy7BjBjc= X-Google-Smtp-Source: ABdhPJxYhSRNOkwgDRc/l2C7Jl258wmN5ml/1qkiBHZtQEnR2mVC77q0+39UpprEXaMpqtbM+otlfoYoA23IDmqOt+I= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a25:ae9f:: with SMTP id b31mr8477359ybj.437.1601416057863; Tue, 29 Sep 2020 14:47:37 -0700 (PDT) Date: Tue, 29 Sep 2020 14:46:30 -0700 In-Reply-To: <20200929214631.3516445-1-samitolvanen@google.com> Message-Id: <20200929214631.3516445-29-samitolvanen@google.com> Mime-Version: 1.0 References: <20200929214631.3516445-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.709.gb0816b6eb0-goog Subject: [PATCH v4 28/29] x86, cpu: disable LTO for cpu.c From: Sami Tolvanen To: Masahiro Yamada , Will Deacon , Steven Rostedt Cc: Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org Clang incorrectly inlines functions with differing stack protector attributes, which breaks __restore_processor_state() that relies on stack protector being disabled. This change disables LTO for cpu.c to work aroung the bug. Link: https://bugs.llvm.org/show_bug.cgi?id=47479 Suggested-by: Nick Desaulniers Signed-off-by: Sami Tolvanen --- arch/x86/power/Makefile | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/power/Makefile b/arch/x86/power/Makefile index 6907b523e856..5f711a441623 100644 --- a/arch/x86/power/Makefile +++ b/arch/x86/power/Makefile @@ -5,5 +5,9 @@ OBJECT_FILES_NON_STANDARD_hibernate_asm_$(BITS).o := y # itself be stack-protected CFLAGS_cpu.o := -fno-stack-protector +# Clang may incorrectly inline functions with stack protector enabled into +# __restore_processor_state(): https://bugs.llvm.org/show_bug.cgi?id=47479 +CFLAGS_REMOVE_cpu.o := $(CC_FLAGS_LTO) + obj-$(CONFIG_PM_SLEEP) += cpu.o obj-$(CONFIG_HIBERNATION) += hibernate_$(BITS).o hibernate_asm_$(BITS).o hibernate.o