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Diffstat (limited to 'arch/x86/kernel/cpu')
-rw-r--r--arch/x86/kernel/cpu/amd.c52
-rw-r--r--arch/x86/kernel/cpu/intel.c25
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 25c559ba8d54..191117f1ad51 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -13,6 +13,7 @@
#include <asm/uaccess.h>
#include <asm/ds.h>
#include <asm/bugs.h>
+#include <asm/cpu.h>
#ifdef CONFIG_X86_64
#include <asm/topology.h>
@@ -110,6 +111,28 @@ 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;
@@ -186,6 +209,8 @@ 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)