Merge branch 'x86/core' into tracing/ftrace

Semantic merge:

  kernel/trace/trace_functions_graph.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>

2 files changed, 77 insertions, 0 deletions

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 25423a5b80ed..f47df59016c5 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -5,6 +5,7 @@
 #include <asm/io.h>
 #include <asm/processor.h>
 #include <asm/apic.h>
+#include <asm/cpu.h>
 
 #ifdef CONFIG_X86_64
 # include <asm/numa_64.h>
@@ -141,6 +142,55 @@ static void __cpuinit init_amd_k6(struct cpuinfo_x86 *c)
         }
 }
 
+static void __cpuinit amd_k7_smp_check(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_SMP
+        /* calling is from identify_secondary_cpu() ? */
+        if (c->cpu_index == boot_cpu_id)
+                return;
+
+        /*
+         * Certain Athlons might work (for various values of 'work') in SMP
+         * but they are not certified as MP capable.
+         */
+        /* Athlon 660/661 is valid. */
+        if ((c->x86_model == 6) && ((c->x86_mask == 0) ||
+            (c->x86_mask == 1)))
+                goto valid_k7;
+
+        /* Duron 670 is valid */
+        if ((c->x86_model == 7) && (c->x86_mask == 0))
+                goto valid_k7;
+
+        /*
+         * Athlon 662, Duron 671, and Athlon >model 7 have capability
+         * bit. It's worth noting that the A5 stepping (662) of some
+         * Athlon XP's have the MP bit set.
+         * See http://www.heise.de/newsticker/data/jow-18.10.01-000 for
+         * more.
+         */
+        if (((c->x86_model == 6) && (c->x86_mask >= 2)) ||
+            ((c->x86_model == 7) && (c->x86_mask >= 1)) ||
+             (c->x86_model > 7))
+                if (cpu_has_mp)
+                        goto valid_k7;
+
+        /* If we get here, not a certified SMP capable AMD system. */
+
+        /*
+         * Don't taint if we are running SMP kernel on a single non-MP
+         * approved Athlon
+         */
+        WARN_ONCE(1, "WARNING: This combination of AMD"
+                "processors is not suitable for SMP.\n");
+        if (!test_taint(TAINT_UNSAFE_SMP))
+                add_taint(TAINT_UNSAFE_SMP);
+
+valid_k7:
+        ;
+#endif
+}
+
 static void __cpuinit init_amd_k7(struct cpuinfo_x86 *c)
 {
         u32 l, h;
@@ -175,6 +225,8 @@ static void __cpuinit init_amd_k7(struct cpuinfo_x86 *c)
         }
 
         set_cpu_cap(c, X86_FEATURE_K7);
+
+        amd_k7_smp_check(c);
 }
 #endif
 
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 1a89a2b68d15..c1c04bf0df77 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -14,6 +14,7 @@
 #include <asm/uaccess.h>
 #include <asm/ds.h>
 #include <asm/bugs.h>
+#include <asm/cpu.h>
 
 #ifdef CONFIG_X86_64
 #include <asm/topology.h>
@@ -116,6 +117,28 @@ static void __cpuinit trap_init_f00f_bug(void)
 }
 #endif
 
+static void __cpuinit intel_smp_check(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_SMP
+        /* calling is from identify_secondary_cpu() ? */
+        if (c->cpu_index == boot_cpu_id)
+                return;
+
+        /*
+         * Mask B, Pentium, but not Pentium MMX
+         */
+        if (c->x86 == 5 &&
+            c->x86_mask >= 1 && c->x86_mask <= 4 &&
+            c->x86_model <= 3) {
+                /*
+                 * Remember we have B step Pentia with bugs
+                 */
+                WARN_ONCE(1, "WARNING: SMP operation may be unreliable"
+                                    "with B stepping processors.\n");
+        }
+#endif
+}
+
 static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c)
 {
         unsigned long lo, hi;
@@ -192,6 +215,8 @@ static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c)
 #ifdef CONFIG_X86_NUMAQ
         numaq_tsc_disable();
 #endif
+
+        intel_smp_check(c);
 }
 #else
 static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c)