Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Len Brown , Linus Torvalds , Peter Zijlstra , Thomas Gleixner , Ingo Molnar , stable@kernel.org Subject: [PATCH 4.14 14/23] x86/apic: Future-proof the TSC_DEADLINE quirk for SKX Date: Sat, 4 Aug 2018 11:01:05 +0200 Message-Id: <20180804082645.391953076@linuxfoundation.org> In-Reply-To: <20180804082643.641435547@linuxfoundation.org> References: <20180804082643.641435547@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Len Brown commit d9e6dbcf28f383bf08e6a3180972f5722e514a54 upstream. All SKX with stepping higher than 4 support the TSC_DEADLINE, no matter the microcode version. Without this patch, upcoming SKX steppings will not be able to use their TSC_DEADLINE timer. Signed-off-by: Len Brown Cc: # v4.14+ Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Fixes: 616dd5872e ("x86/apic: Update TSC_DEADLINE quirk with additional SKX stepping") Link: http://lkml.kernel.org/r/d0c7129e509660be9ec6b233284b8d42d90659e8.1532207856.git.len.brown@intel.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/apic/apic.c | 3 +++ 1 file changed, 3 insertions(+) --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -580,6 +580,9 @@ static u32 skx_deadline_rev(void) case 0x04: return 0x02000014; } + if (boot_cpu_data.x86_stepping > 4) + return 0; + return ~0U; }