Home Home > GIT Browse
diff options
authorLen Brown <len.brown@intel.com>2018-07-21 17:19:19 -0400
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2018-08-06 16:20:49 +0200
commit7cf6b325f5545ba41953e2a49267632ea3a78af8 (patch)
parent34a938cd3ad45b5c6d67d83329ce1dcf239863a8 (diff)
x86/apic: Future-proof the TSC_DEADLINE quirk for SKX
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 <len.brown@intel.com> Cc: <stable@kernel.org> # v4.14+ Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> 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 <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index ebdcc368a2d3..f48a51335538 100644
--- 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;