Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756136Ab2E3B0k (ORCPT ); Tue, 29 May 2012 21:26:40 -0400 Received: from rcsinet15.oracle.com ([148.87.113.117]:36252 "EHLO rcsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754178Ab2E3B0j convert rfc822-to-8bit (ORCPT ); Tue, 29 May 2012 21:26:39 -0400 MIME-Version: 1.0 Message-ID: Date: Tue, 29 May 2012 18:26:25 -0700 (PDT) From: Zhenzhong Duan To: Cc: , , , , , , Subject: =?UTF-8?B?562U5aSNOiBSZTogW1BBVENIXSBGaXggYW4gb3Zl?= =?UTF-8?B?cmZsb3cgaW4gcmFuZ2VfdG9fbXRyciBmdW5j?= X-Mailer: Zimbra on Oracle Beehive Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Content-Disposition: inline X-Source-IP: ucsinet22.oracle.com [156.151.31.94] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1812 Lines: 51 ----- yinghai@kernel.org 写道： > On Mon, May 28, 2012 at 5:29 AM, Zhenzhong Duan > wrote: > > When boot x86_64 kernel on sun G5+ with 4T mem, see an overflow in > mtrr cleanup as below. > > > > *BAD*gran_size: 2G      chunk_size: 2G  num_reg: 10     lose cover > RAM: > > -18014398505283592M > > > > This is because 1<<31 sign extended. > > Use explicit type conversion to force a 64bit constant to fix it. > > Useful for mem larger than or equal to 4T. > > > > Signed-off-by: Zhenzhong Duan > > --- > >  arch/x86/kernel/cpu/mtrr/cleanup.c |    2 +- > >  1 files changed, 1 insertions(+), 1 deletions(-) > > > > diff --git a/arch/x86/kernel/cpu/mtrr/cleanup.c > b/arch/x86/kernel/cpu/mtrr/cleanup.c > > index ac140c7..853a4c6 100644 > > --- a/arch/x86/kernel/cpu/mtrr/cleanup.c > > +++ b/arch/x86/kernel/cpu/mtrr/cleanup.c > > @@ -266,7 +266,7 @@ range_to_mtrr(unsigned int reg, unsigned long > range_startk, > >                if (align > max_align) > >                        align = max_align; > > > > -               sizek = 1 << align; > > +               sizek = (unsigned long)1 << align; > > how about > > sizek = 1UL << align; > > > >                if (debug_print) { > >                        char start_factor = 'K', size_factor = 'K'; > >                        unsigned long start_base, size_base; > > -- > > 1.7.3 > > Yes, this looks more clean although same compiling result. Should i resend it? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/