From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751172AbdGOAil (ORCPT ); Fri, 14 Jul 2017 20:38:41 -0400 Received: from mail-pf0-f172.google.com ([209.85.192.172]:33010 "EHLO mail-pf0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751061AbdGOAij (ORCPT ); Fri, 14 Jul 2017 20:38:39 -0400 Date: Fri, 14 Jul 2017 17:38:36 -0700 From: Kees Cook To: linux-kernel@vger.kernel.org Cc: devicetree@vger.kernel.org, Rob Herring , Ard Biesheuvel , Matt Redfearn Subject: [PATCH] Documentation: dt: chosen property for kaslr-seed Message-ID: <20170715003836.GA113132@beast> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Document then /chosen/kaslr-seed property (and its interaction with the EFI_RNG_PROTOCOL API). Signed-off-by: Kees Cook --- Documentation/devicetree/bindings/chosen.txt | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) diff --git a/Documentation/devicetree/bindings/chosen.txt b/Documentation/devicetree/bindings/chosen.txt index dee3f5d9df26..0cdb43b268e5 100644 --- a/Documentation/devicetree/bindings/chosen.txt +++ b/Documentation/devicetree/bindings/chosen.txt @@ -5,9 +5,27 @@ The chosen node does not represent a real device, but serves as a place for passing data between firmware and the operating system, like boot arguments. Data in the chosen node does not represent the hardware. +The following properties are recognized: -stdout-path property --------------------- + +kaslr-seed +----------- + +This property is used when booting with CONFIG_RANDOMIZE_BASE to seed +the entropy used to randomize the kernel image base address location. It +is parsed as a u64 value, e.g. + +/ { + chosen { + kaslr-seed = <0xfeedbeef 0xc0def00d>; + }; +}; + +Note that when booting through EFI when EFI_RNG_PROTOCOL is supported, +this value will be overwritten by the EFI stub. + +stdout-path +----------- Device trees may specify the device to be used for boot console output with a stdout-path property under /chosen, as described in the Devicetree -- 2.7.4 -- Kees Cook Pixel Security