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 S1751619Ab3FYS1r (ORCPT <rfc822;w@1wt.eu>);
	Tue, 25 Jun 2013 14:27:47 -0400
Received: from mga14.intel.com ([143.182.124.37]:23443 "EHLO mga14.intel.com"
	rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
	id S1751005Ab3FYS1q (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
	Tue, 25 Jun 2013 14:27:46 -0400
X-ExtLoop1: 1
X-IronPort-AV: E=Sophos;i="4.87,938,1363158000"; 
   d="scan'208";a="260015777"
Date: Tue, 25 Jun 2013 21:31:23 +0300
From: Mika Westerberg <mika.westerberg@linux.intel.com>
To: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Bjorn Helgaas <bhelgaas@google.com>,
        "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
        Jesse Barnes <jbarnes@virtuousgeek.org>,
        Yinghai Lu <yinghai@kernel.org>, john.ronciak@intel.com,
        miles.j.penner@intel.com, bruce.w.allan@intel.com,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Heikki Krogerus <heikki.krogerus@linux.intel.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        linux-pci@vger.kernel.org, x86@kernel.org
Subject: Re: [PATCH 5/6] PCI: acpiphp: look _RMV method a bit deeper in the
 hierarhcy
Message-ID: <20130625183123.GJ9294@intel.com>
References: <1372177330-28013-1-git-send-email-mika.westerberg@linux.intel.com>
 <1372177330-28013-6-git-send-email-mika.westerberg@linux.intel.com>
 <CAHp75Vd2Torku6zy2awLHRTed9mx94a6RAu+oHJYb+rVgZKBDQ@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAHp75Vd2Torku6zy2awLHRTed9mx94a6RAu+oHJYb+rVgZKBDQ@mail.gmail.com>
Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo
User-Agent: Mutt/1.5.21 (2010-09-15)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Tue, Jun 25, 2013 at 09:15:47PM +0300, Andy Shevchenko wrote:
> On Tue, Jun 25, 2013 at 7:22 PM, Mika Westerberg
> <mika.westerberg@linux.intel.com> wrote:
> 
> > The acpiphp driver finds out whether the device is hotpluggable by checking
> > whether it has _RMV method behind it (and if it returns 1). However, at
> > least Acer Aspire S5 with Thunderbolt host router has this method placed
> > behind device called EPUP (endpoint upstream port?) and not directly behind
> > the root port as can be seen from the ASL code below:
> 
> []
> 
> 
> > +static acpi_status pcihp_evaluate_rmv(acpi_handle handle, u32 lvl,
> > +                                     void *context, void **return_not_used)
> > +{
> > +       unsigned long long *removable = context;
> > +       unsigned long long value;
> > +       acpi_status status;
> > +
> > +       status = acpi_evaluate_integer(handle, "_RMV", NULL, &value);
> > +       if (ACPI_SUCCESS(status) && value) {
> 
> So, there is a chance the caller gets back uninitialized *context.
> Let's assume that is by design.
> 
> > +               *removable = value;
> > +               return AE_CTRL_TERMINATE;
> > +       }
> > +       return AE_OK;
> > +}
> 
> 
> > +static bool pcihp_is_removable(acpi_handle handle, size_t depth)
> > +{
> > +       unsigned long long removable = 0;
> > +       acpi_status status;
> > +
> > +       status = pcihp_evaluate_rmv(handle, 0, &removable, NULL);
> > +       if ((status == AE_CTRL_TERMINATE) && removable)
> 
> Here you already have removable not equal zero.

Hmm, removable is initialized to zero just few lines above... Did I miss
something obvious?

> Internal braces could be removed, but it's up top you.

I'll remove them in the next revision.

Thanks.