Messages in this thread Patch in this message | | | Date | Wed, 29 Oct 2014 02:10:11 -0700 | From | tip-bot for Dave Jones <> | Subject | [tip:x86/urgent] x86: Don' t enable F00F workaround on Intel Quark processors |
| |
Commit-ID: d4e1a0af1d3a88cdfc8c954d3005eb8745ec518d Gitweb: http://git.kernel.org/tip/d4e1a0af1d3a88cdfc8c954d3005eb8745ec518d Author: Dave Jones <davej@redhat.com> AuthorDate: Tue, 28 Oct 2014 13:57:53 -0400 Committer: Ingo Molnar <mingo@kernel.org> CommitDate: Wed, 29 Oct 2014 08:52:09 +0100
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 <davej@redhat.com> Cc: Bryan O'Donoghue <pure.logic@nexus-software.ie> Link: http://lkml.kernel.org/r/20141028175753.GA12743@redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> --- 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 1ef4562..9cc6b6f 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);
| |