1 files changed, 18 insertions, 1 deletions

diff --git a/arch/i386/kernel/smpboot.c b/arch/i386/kernel/smpboot.c
index efe07990e7fc..020d873b7d21 100644
--- a/arch/i386/kernel/smpboot.c
+++ b/arch/i386/kernel/smpboot.c
@@ -177,6 +177,9 @@ static void __devinit smp_store_cpu_info(int id)
          */
         if ((c->x86_vendor == X86_VENDOR_AMD) && (c->x86 == 6)) {
 
+                if (num_possible_cpus() == 1)
+                        goto valid_k7;
+
                 /* Athlon 660/661 is valid. */  
                 if ((c->x86_model==6) && ((c->x86_mask==0) || (c->x86_mask==1)))
                         goto valid_k7;
@@ -1376,7 +1379,8 @@ int __cpu_disable(void)
          */
         if (cpu == 0)
                 return -EBUSY;
-
+        if (nmi_watchdog == NMI_LOCAL_APIC)
+                stop_apic_nmi_watchdog(NULL);
         clear_local_APIC();
         /* Allow any queued timer interrupts to get serviced */
         local_irq_enable();
@@ -1490,3 +1494,16 @@ void __init smp_intr_init(void)
         /* IPI for generic function call */
         set_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt);
 }
+
+/*
+ * If the BIOS enumerates physical processors before logical,
+ * maxcpus=N at enumeration-time can be used to disable HT.
+ */
+static int __init parse_maxcpus(char *arg)
+{
+        extern unsigned int maxcpus;
+
+        maxcpus = simple_strtoul(arg, NULL, 0);
+        return 0;
+}
+early_param("maxcpus", parse_maxcpus);