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 S1752120AbeDSGf5 (ORCPT <rfc822;w@1wt.eu>);
        Thu, 19 Apr 2018 02:35:57 -0400
Received: from mx2.suse.de ([195.135.220.15]:40965 "EHLO mx2.suse.de"
        rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
        id S1751953AbeDSGf4 (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
        Thu, 19 Apr 2018 02:35:56 -0400
Date: Thu, 19 Apr 2018 08:35:37 +0200 (CEST)
From: Jiri Kosina <jikos@kernel.org>
To: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
cc: "Kirill A. Shutemov" <kirill@shutemov.name>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
        linux-kernel@vger.kernel.org, x86@kernel.org
Subject: Re: [PATCH] x86/mm: vmemmap and vmalloc base addressess are usngined
 longs
In-Reply-To: <20180416094603.fj3wevho5j7wy7s6@black.fi.intel.com>
Message-ID: <nycvar.YFH.7.76.1804181143500.28129@cbobk.fhfr.pm>
References: <nycvar.YFH.7.76.1804121437350.28129@cbobk.fhfr.pm> <20180412142801.oi7bzju3frgkdskp@node.shutemov.name> <nycvar.YFH.7.76.1804161133500.28129@cbobk.fhfr.pm> <20180416094603.fj3wevho5j7wy7s6@black.fi.intel.com>
User-Agent: Alpine 2.21 (LSU 202 2017-01-01)
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Mon, 16 Apr 2018, Kirill A. Shutemov wrote:

> > > > Commits 9b46a051e4 ("x86/mm: Initialize vmemmap_base at boot-time") and 
> > > > a7412546d8 ("x86/mm: Adjust vmalloc base and size at boot-time") lost the 
> > > > type information for __VMALLOC_BASE_L4, __VMALLOC_BASE_L5, 
> > > > __VMEMMAP_BASE_L4 and __VMEMMAP_BASE_L5 constants.
> > > > 
> > > > Let's declare them explicitly unsigned long again.
> > > 
> > > It is just cosmetics, right? I mean these literals are 'unsigned long'
> > > anyway.
> > 
> > Yeah, I can't imagine this particular case leading to any overflow 
> > scenario, as the literal is big enough to be automatically treated as 
> > unsigned long by the compiler, but it shuts up sparse which treats this as 
> > a generic case (where the missing UL might be a problem), and totally 
> > pollutes the build output.
> > 
> > Either we put the 'UL' there, or teach sparse about figuring out the 
> > 'closer bigger fitting type' for hexadecimal literals, which might be more 
> > tricky.
> 
> I don't have a problem with the patch:
> 
> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>

x86 folks, any objections to merging this? Without it, the sparse build is 
currently totally unreadable mess.

Thanks,

-- 
Jiri Kosina
SUSE Labs