From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752970AbdJSWrD (ORCPT ); Thu, 19 Oct 2017 18:47:03 -0400 Received: from bombadil.infradead.org ([65.50.211.133]:57804 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752092AbdJSWrB (ORCPT ); Thu, 19 Oct 2017 18:47:01 -0400 Date: Thu, 19 Oct 2017 15:46:54 -0700 From: Darren Hart To: Mario.Limonciello@dell.com Cc: pali.rohar@gmail.com, andy.shevchenko@gmail.com, linux-kernel@vger.kernel.org, platform-driver-x86@vger.kernel.org, luto@kernel.org, quasisec@google.com, rjw@rjwysocki.net, mjg59@google.com, hch@lst.de, greg@kroah.com, gnomes@lxorguk.ukuu.org.uk Subject: Re: [PATCH v10 11/15] platform/x86: dell-smbios-smm: test for WSMT Message-ID: <20171019224654.GC1097@fury> References: <657d281490de3d0a60f210f8bc57e075c9afc40e.1508434514.git.mario.limonciello@dell.com> <20171019180926.h6lnfwnapswybtcb@pali> <9065712bf6b14fc680ba03738b369947@ausx13mpc120.AMER.DELL.COM> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <9065712bf6b14fc680ba03738b369947@ausx13mpc120.AMER.DELL.COM> User-Agent: Mutt/1.8.0 (2017-02-23) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 19, 2017 at 06:12:09PM +0000, Mario.Limonciello@dell.com wrote: > > -----Original Message----- > > From: Pali Rohár [mailto:pali.rohar@gmail.com] > > Sent: Thursday, October 19, 2017 1:09 PM > > To: Limonciello, Mario > > Cc: dvhart@infradead.org; Andy Shevchenko ; > > LKML ; platform-driver-x86@vger.kernel.org; Andy > > Lutomirski ; quasisec@google.com; rjw@rjwysocki.net; > > mjg59@google.com; hch@lst.de; Greg KH ; Alan Cox > > > > Subject: Re: [PATCH v10 11/15] platform/x86: dell-smbios-smm: test for WSMT > > > > On Thursday 19 October 2017 12:50:14 Mario Limonciello wrote: > > > +/* When enabled this indicates that SMM won't work */ > > > +static bool test_wsmt_enabled(void) > > > +{ > > > + struct calling_interface_token *token; > > > + > > > + /* if token doesn't exist, SMM will work */ > > > + token = dell_smbios_find_token(WSMT_EN_TOKEN); > > > + if (!token) > > > + return false; > > > + > > > + /* if token exists, try to access over SMM */ > > > + buffer->class = CLASS_TOKEN_READ; > > > + buffer->select = SELECT_TOKEN_STD; > > > + memset(buffer, 0, sizeof(struct calling_interface_buffer)); > > > + buffer->input[0] = token->location; > > > + dell_smbios_smm_call(buffer); > > > + > > > + /* if lookup failed, we know WSMT was enabled */ > > > + if (buffer->output[0] != 0) > > > + return true; > > > + > > > + /* query token status if it didn't fail */ > > > + return (buffer->output[1] == token->value); > > > +} > > > + > > > static int __init dell_smbios_smm_init(void) > > > { > > > int ret; > > > @@ -115,6 +140,13 @@ static int __init dell_smbios_smm_init(void) > > > > > > dmi_walk(find_cmd_address, NULL); > > > > > > + ret = test_wsmt_enabled(); > > > > ret is int, but test_wsmt_enabled() returns bool. > > Yes, ret is re-used within this method. > 0, 1 enum is a subset of int, so this seemed like a logical thing to me to do. Agreed, the conversion is automatic and he tests for it and returns an appropriate error code. I don't see a real problem with this. -- Darren Hart VMware Open Source Technology Center