From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1757689AbdLTWDq (ORCPT <rfc822;w@1wt.eu>);
        Wed, 20 Dec 2017 17:03:46 -0500
Received: from Galois.linutronix.de ([146.0.238.70]:52940 "EHLO
        Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1757196AbdLTV5v (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Wed, 20 Dec 2017 16:57:51 -0500
Message-Id: <20171220215443.664432754@linutronix.de>
User-Agent: quilt/0.63-1
Date: Wed, 20 Dec 2017 22:35:40 +0100
From: Thomas Gleixner <tglx@linutronix.de>
To: LKML <linux-kernel@vger.kernel.org>
Cc: x86@kernel.org, Linus Torvalds <torvalds@linux-foundation.org>,
        Andy Lutomirsky <luto@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Dave Hansen <dave.hansen@intel.com>, Borislav Petkov <bpetkov@suse.de>,
        Greg KH <gregkh@linuxfoundation.org>, keescook@google.com,
        hughd@google.com, Brian Gerst <brgerst@gmail.com>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        Denys Vlasenko <dvlasenk@redhat.com>, Rik van Riel <riel@redhat.com>,
        Boris Ostrovsky <boris.ostrovsky@oracle.com>,
        Juergen Gross <jgross@suse.com>,
        David Laight <David.Laight@aculab.com>,
        Eduardo Valentin <eduval@amazon.com>, aliguori@amazon.com,
        Will Deacon <will.deacon@arm.com>, Vlastimil Babka <vbabka@suse.cz>,
        daniel.gruss@iaik.tugraz.at, Kees Cook <keescook@chromium.org>,
        Borislav Petkov <bp@alien8.de>
Subject: [patch V181 37/54] x86/mm/pti: Map ESPFIX into user space
References: <20171220213503.672610178@linutronix.de>
MIME-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-15
Content-Disposition: inline;
 filename=x86-mm-pti--Map-ESPFIX-into-user-space.patch
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

From: Andy Lutomirski <luto@kernel.org>

Map the ESPFIX pages into user space when PTI is enabled.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Borislav Petkov <bp@alien8.de>
---
 arch/x86/mm/pti.c |   11 +++++++++++
 1 file changed, 11 insertions(+)

--- a/arch/x86/mm/pti.c
+++ b/arch/x86/mm/pti.c
@@ -256,6 +256,16 @@ static void __init pti_clone_user_shared
 }
 
 /*
+ * Clone the ESPFIX P4D into the user space visinble page table
+ */
+static void __init pti_setup_espfix64(void)
+{
+#ifdef CONFIG_X86_ESPFIX64
+	pti_clone_p4d(ESPFIX_BASE_ADDR);
+#endif
+}
+
+/*
  * Clone the populated PMDs of the entry and irqentry text and force it RO.
  */
 static void __init pti_clone_entry_text(void)
@@ -276,4 +286,5 @@ void __init pti_init(void)
 
 	pti_clone_user_shared();
 	pti_clone_entry_text();
+	pti_setup_espfix64();
 }