Received: by 2002:a25:86ce:0:0:0:0:0 with SMTP id y14csp454491ybm; Mon, 20 May 2019 20:16:15 -0700 (PDT) X-Google-Smtp-Source: APXvYqxHco2QCpWbuUgYB8iyudwcyTltWgXt3EwikgB/jsDiO5HFC0BOf7NOZQuaIuyND2wOV11T X-Received: by 2002:a17:902:12d:: with SMTP id 42mr72784938plb.4.1558408575228; Mon, 20 May 2019 20:16:15 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1558408575; cv=none; d=google.com; s=arc-20160816; b=UFmmqU01blUyrrooJGwJbRvsJtea5gaULarWJlyKkSO3scALJr85DEjCBbF1R4entT vynYrxnDWIT4+ZYY73oqd9YVQVXxMC5cV+j/ii4UpD+cfHxKKQrsmngnCeswx+sqk97g j78X6HugNzOHoUAoEOu2swPFtHXQyBnnDLirHEZXYN00QNSB7WXRIGsEj3tR8reo2Df/ a2JgSTLgRW/Xjhzk9sGVcFm5Y7SgZFfHbrVR4Mc2JhKd9mjJTl/pDqIIcL0DP3GR+R2m k6zkj071MRjnq+KejwtH4jSZltNClC4sZ+V924KZYULkMS7GqmOeWFFXLKRZN4zHpCn/ EjVg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:message-id:from:cc:to:subject :content-transfer-encoding:mime-version:references:in-reply-to :user-agent:date:dkim-signature:dkim-filter; bh=aiRlJguT2uUGYCs0b9eGTl9PzBot2H8W+Hal5KY2RqE=; b=BYYo9+rr83UNLpMSkYx1fZT9LNRhLa1FXpN2PIGKPtLldyFpWvlvB3miKERUDQ3nCr mfauqmU8h/RUIavLDWX0CsKCkWgeGo7JQxYYBa57SGkUeVZ9pi7JhC+Q0sLisbTUh0SU m5wTz6mlNpSMrUKhM8P7mWltVMCxLUx9sUHSFS3mDdZVxFXhjSlsCXLIOY0DA5I8awp9 CoOuRjouzHxJeGaTBPVj5d4xG5x2KrI+dTP+kTzrUnXAonH7W4Cb9IYVZNsg9HNtHWGB s+35IxJtKEi5UDp1IzciZEMgVO31JngBp0StIMgUsSDhyjTcQRhq8dRd54TH1fodGQsQ 0trg== ARC-Authentication-Results: i=1; mx.google.com; dkim=fail header.i=@zytor.com header.s=2019051801 header.b=ko1F5kNq; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=zytor.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id c14si770074pgd.314.2019.05.20.20.15.59; Mon, 20 May 2019 20:16:15 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=fail header.i=@zytor.com header.s=2019051801 header.b=ko1F5kNq; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=zytor.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727108AbfEUDNw (ORCPT + 99 others); Mon, 20 May 2019 23:13:52 -0400 Received: from terminus.zytor.com ([198.137.202.136]:54679 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726283AbfEUDNw (ORCPT ); Mon, 20 May 2019 23:13:52 -0400 Received: from [IPv6:2601:646:8600:3281:5064:d7ea:6358:1f15] ([IPv6:2601:646:8600:3281:5064:d7ea:6358:1f15]) (authenticated bits=0) by mail.zytor.com (8.15.2/8.15.2) with ESMTPSA id x4L3D2bH2993928 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NO); Mon, 20 May 2019 20:13:05 -0700 DKIM-Filter: OpenDKIM Filter v2.11.0 mail.zytor.com x4L3D2bH2993928 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zytor.com; s=2019051801; t=1558408387; bh=aiRlJguT2uUGYCs0b9eGTl9PzBot2H8W+Hal5KY2RqE=; h=Date:In-Reply-To:References:Subject:To:CC:From:From; b=ko1F5kNq5n1OHIo6F0Zc2qrfDqkUvuRQWq9C5/+EaUAE/m1EeM5WJu+m0+utA6TK3 Ft9kkLJbq1ckQkwevWJA3WrvpJpy4PyivMqzM9C3R3Vmo5GXsksuj6qEG2+db/apqQ BBGSdtNO/SHn6wPEBb0sf6jOQJ6ofU+VmbsGgoTjJmSrkyHWgFP9EScizv1jYeiPHL Ibb8Upegp3dk3mWDtAwsuMXDhgT2zSYt+yUyjN6nQLJIuoYdtSkoJsbb2Et8gPjfFF 4Zu/M78BlTbtuw1tCd8I5C+kqt/N55WKncdKA2pi53se74qg0kIvXwGk9JMqGqDylC YMgUtr60m94iQ== Date: Mon, 20 May 2019 20:12:55 -0700 User-Agent: K-9 Mail for Android In-Reply-To: <20190520231948.49693-4-thgarnie@chromium.org> References: <20190520231948.49693-1-thgarnie@chromium.org> <20190520231948.49693-4-thgarnie@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [PATCH v7 03/12] x86: Add macro to get symbol address for PIE support To: Thomas Garnier , kernel-hardening@lists.openwall.com CC: kristen@linux.intel.com, Thomas Garnier , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, Peter Zijlstra , Nadav Amit , Jann Horn , linux-kernel@vger.kernel.org From: hpa@zytor.com Message-ID: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On May 20, 2019 4:19:28 PM PDT, Thomas Garnier wr= ote: >From: Thomas Garnier > >Add a new _ASM_MOVABS macro to fetch a symbol address=2E It will be used >to replace "_ASM_MOV $, %dst" code construct that are not >compatible with PIE=2E > >Signed-off-by: Thomas Garnier >--- > arch/x86/include/asm/asm=2Eh | 1 + > 1 file changed, 1 insertion(+) > >diff --git a/arch/x86/include/asm/asm=2Eh b/arch/x86/include/asm/asm=2Eh >index 3ff577c0b102=2E=2E3a686057e882 100644 >--- a/arch/x86/include/asm/asm=2Eh >+++ b/arch/x86/include/asm/asm=2Eh >@@ -30,6 +30,7 @@ > #define _ASM_ALIGN __ASM_SEL(=2Ebalign 4, =2Ebalign 8) >=20 > #define _ASM_MOV __ASM_SIZE(mov) >+#define _ASM_MOVABS __ASM_SEL(movl, movabsq) > #define _ASM_INC __ASM_SIZE(inc) > #define _ASM_DEC __ASM_SIZE(dec) > #define _ASM_ADD __ASM_SIZE(add) This is just about *always* wrong on x86-86=2E We should be using leaq sym= (%rip),%reg=2E If it isn't reachable by leaq, then it is a non-PIE symbol l= ike percpu=2E You do have to keep those distinct! --=20 Sent from my Android device with K-9 Mail=2E Please excuse my brevity=2E