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[209.132.180.67]) by mx.google.com with ESMTP id k6-v6si2397453pgk.256.2018.05.31.13.40.07; Thu, 31 May 2018 13:40:21 -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=pass header.i=@kernel.org header.s=default header.b=mMWVEXtW; 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=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754664AbeEaUib (ORCPT + 99 others); Thu, 31 May 2018 16:38:31 -0400 Received: from mail.kernel.org ([198.145.29.99]:52120 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754479AbeEaUia (ORCPT ); Thu, 31 May 2018 16:38:30 -0400 Received: from mail-wm0-f53.google.com (mail-wm0-f53.google.com [74.125.82.53]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 09191208B6 for ; Thu, 31 May 2018 20:38:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1527799110; bh=+F/V5v8OZILvf8wlBWsqR80JRUku1sFq1gLomVdP5Gw=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=mMWVEXtW8PjVHcBlQe2wC2GPRu56K5I1400Dwwr5udCCUBzXLgTyyCbo51s/cVLME GUjCdEv4cSw7wk3c7Kw+wxY35DVs3iKo1BI4B7qMVcFHAgLR3rOyDbqBMyFxserb/v ySH3nK4fF1Q9uZ9u7+3GEI8YLBef7lMVWNp0xG+o= Received: by mail-wm0-f53.google.com with SMTP id x2-v6so48722671wmh.5 for ; Thu, 31 May 2018 13:38:29 -0700 (PDT) X-Gm-Message-State: ALKqPwfNHjbzHh0IkwIqMzsTHYLgT2gfyO02ACDTcOlEG9fhSxXzLfM8 qQmyemEMh551D/QAmxMxMAEag7XCVTLdtJkvenY26A== X-Received: by 2002:a1c:1082:: with SMTP id 124-v6mr793614wmq.46.1527799108558; Thu, 31 May 2018 13:38:28 -0700 (PDT) MIME-Version: 1.0 References: <1527789525-8857-1-git-send-email-chang.seok.bae@intel.com> <1527789525-8857-3-git-send-email-chang.seok.bae@intel.com> <7A65BD11-6A84-4CDF-9FF7-34303BABBDD1@zytor.com> In-Reply-To: <7A65BD11-6A84-4CDF-9FF7-34303BABBDD1@zytor.com> From: Andy Lutomirski Date: Thu, 31 May 2018 13:38:17 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH V2 02/15] x86/fsgsbase/64: Make ptrace read FS/GS base accurately To: "H. Peter Anvin" Cc: Andrew Lutomirski , "Bae, Chang Seok" , Thomas Gleixner , Ingo Molnar , Andi Kleen , Dave Hansen , "Metzger, Markus T" , "Ravi V. Shankar" , LKML 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 On Thu, May 31, 2018 at 1:31 PM wrote: > > On May 31, 2018 1:14:59 PM PDT, Andy Lutomirski wrote: > >On Thu, May 31, 2018 at 10:58 AM Chang S. Bae > > wrote: > >> > >> From: Andy Lutomirski > >> > >> ptrace can read FS/GS base using the register access API > >> (PTRACE_PEEKUSER, etc) or PTRACE_ARCH_PRCTL. Make both of these > >> mechanisms return the actual FS/GS base. > >> > >> This will improve debuggability by providing the correct information > >> to ptracer (GDB and etc). > > > >LGTM. > > LGTM? Looks good to me.