From 383073d49fc78aa793c51018e29253c83410401e Mon Sep 17 00:00:00 2001 From: Zhao Yakui <yakui.zhao@intel.com> Date: Fri, 11 Dec 2009 15:17:20 +0800 Subject: [PATCH] ACPI: Use the ARB_DISABLE for the CPU which model id is less than 0x0f. commit 03a05ed1152944000151d57b71000de287a1eb02 upstream. Currently, 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 Signed-off-by: Zhao Yakui <yakui.zhao@intel.com> Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> --- arch/x86/kernel/acpi/cstate.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/acpi/cstate.c b/arch/x86/kernel/acpi/cstate.c index 59cdfa4686b2..2e837f5080fe 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); -- 2.34.1