From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefan Bader Subject: Re: [PATCH] acpi: Use the ARB_DISABLE for the CPU which model id is less than 0x0f. Date: Thu, 10 Dec 2009 14:41:54 +0100 Message-ID: <4B20FAA2.3040405@canonical.com> References: <1260102002-18624-1-git-send-email-yakui.zhao@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Return-path: Received: from adelie.canonical.com ([91.189.90.139]:49632 "EHLO adelie.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758789AbZLJNlz (ORCPT ); Thu, 10 Dec 2009 08:41:55 -0500 In-Reply-To: <1260102002-18624-1-git-send-email-yakui.zhao@intel.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: yakui.zhao@intel.com Cc: lenb@kernel.org, linux-acpi@vger.kernel.org, "Pallipadi, Venkatesh" I think, this should go to stable, too. -Stefan yakui.zhao@intel.com wrote: > From: Zhao Yakui > > ARB_DISABLE is a NOP on all of the recent Intel platforms. For such platforms, > reduce contention on c3_lock by skipping the fake ARB_DISABLE. > > The cpu model id on one laptop is 14. If we disable ARB_DISABLE on this box, > the box can't be booted correctly. But if we still enable ARB_DISABLE on this > box, the box can be booted correctly. > > So we still use the ARB_DISABLE for the cpu which mode id is less than 0x0f. > > http://bugzilla.kernel.org/show_bug.cgi?id=14700 CC: stable@kernel.org > Signed-off-by: Zhao Yakui > cc: Pallipadi, Venkatesh > --- > arch/x86/kernel/acpi/cstate.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/arch/x86/kernel/acpi/cstate.c b/arch/x86/kernel/acpi/cstate.c > index 59cdfa4..2e837f5 100644 > --- a/arch/x86/kernel/acpi/cstate.c > +++ b/arch/x86/kernel/acpi/cstate.c > @@ -48,7 +48,7 @@ void acpi_processor_power_init_bm_check(struct acpi_processor_flags *flags, > * P4, Core and beyond CPUs > */ > if (c->x86_vendor == X86_VENDOR_INTEL && > - (c->x86 > 0xf || (c->x86 == 6 && c->x86_model >= 14))) > + (c->x86 > 0xf || (c->x86 == 6 && c->x86_model >= 0x0f))) > flags->bm_control = 0; > } > EXPORT_SYMBOL(acpi_processor_power_init_bm_check);