x86/l1tf: Show actual SMT state

commit 130d6f946f6f2a972ee3ec8540b7243ab99abe97 upstream.

Use the now exposed real SMT state, not the SMT sysfs control knob
state. This reflects the state of the system when the mitigation status is
queried.

This does not change the warning in the VMX launch code. There the
dependency on the control knob makes sense because siblings could be
brought online anytime after launching the VM.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Casey Schaufler <casey.schaufler@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: Waiman Long <longman9394@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Dave Stewart <david.c.stewart@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20181125185004.613357354@linutronix.de
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 6ae729caf75e2d70f65cee43f23c2fe11ee84c90..2ae8cdc8b68c465f1b0f523e3489388872496594 100644 (file)
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -838,13 +838,14 @@ static ssize_t l1tf_show_state(char *buf)
 
        if (l1tf_vmx_mitigation == VMENTER_L1D_FLUSH_EPT_DISABLED ||
            (l1tf_vmx_mitigation == VMENTER_L1D_FLUSH_NEVER &&
-            cpu_smt_control == CPU_SMT_ENABLED))
+            sched_smt_active())) {
                return sprintf(buf, "%s; VMX: %s\n", L1TF_DEFAULT_MSG,
                               l1tf_vmx_states[l1tf_vmx_mitigation]);
+       }
 
        return sprintf(buf, "%s; VMX: %s, SMT %s\n", L1TF_DEFAULT_MSG,
                       l1tf_vmx_states[l1tf_vmx_mitigation],
-                      cpu_smt_control == CPU_SMT_ENABLED ? "vulnerable" : "disabled");
+                      sched_smt_active() ? "vulnerable" : "disabled");
 }
 #else
 static ssize_t l1tf_show_state(char *buf)