From d4e1a0af1d3a88cdfc8c954d3005eb8745ec518d Mon Sep 17 00:00:00 2001 From: Dave Jones Date: Tue, 28 Oct 2014 13:57:53 -0400 Subject: [PATCH] x86: Don't enable F00F workaround on Intel Quark processors The Intel Quark processor is a part of family 5, but does not have the F00F bug present in Pentiums of the same family. Pentiums were models 0 through 8, Quark is model 9. Signed-off-by: Dave Jones Cc: Bryan O'Donoghue Link: http://lkml.kernel.org/r/20141028175753.GA12743@redhat.com Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/intel.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c index 1ef456273172..9cc6b6f25f42 100644 --- a/arch/x86/kernel/cpu/intel.c +++ b/arch/x86/kernel/cpu/intel.c @@ -213,12 +213,13 @@ static void intel_workarounds(struct cpuinfo_x86 *c) { #ifdef CONFIG_X86_F00F_BUG /* - * All current models of Pentium and Pentium with MMX technology CPUs + * All models of Pentium and Pentium with MMX technology CPUs * have the F0 0F bug, which lets nonprivileged users lock up the * system. Announce that the fault handler will be checking for it. + * The Quark is also family 5, but does not have the same bug. */ clear_cpu_bug(c, X86_BUG_F00F); - if (!paravirt_enabled() && c->x86 == 5) { + if (!paravirt_enabled() && c->x86 == 5 && c->x86_model < 9) { static int f00f_workaround_enabled; set_cpu_bug(c, X86_BUG_F00F); -- 2.20.1