6 files changed, 30 insertions, 14 deletions

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index a7b6dec6fc3f..0a60d60ed036 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -235,8 +235,9 @@ static int iommu_completion_wait(struct amd_iommu *iommu)
         status &= ~MMIO_STATUS_COM_WAIT_INT_MASK;
         writel(status, iommu->mmio_base + MMIO_STATUS_OFFSET);
 
-        if (unlikely((i == EXIT_LOOP_COUNT) && printk_ratelimit()))
-                printk(KERN_WARNING "AMD IOMMU: Completion wait loop failed\n");
+        if (unlikely(i == EXIT_LOOP_COUNT))
+                panic("AMD IOMMU: Completion wait loop failed\n");
+
 out:
         spin_unlock_irqrestore(&iommu->lock, flags);
 
diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c
index 30ae2701b3df..c6cc22815d35 100644
--- a/arch/x86/kernel/amd_iommu_init.c
+++ b/arch/x86/kernel/amd_iommu_init.c
@@ -427,6 +427,10 @@ static u8 * __init alloc_command_buffer(struct amd_iommu *iommu)
         memcpy_toio(iommu->mmio_base + MMIO_CMD_BUF_OFFSET,
                         &entry, sizeof(entry));
 
+        /* set head and tail to zero manually */
+        writel(0x00, iommu->mmio_base + MMIO_CMD_HEAD_OFFSET);
+        writel(0x00, iommu->mmio_base + MMIO_CMD_TAIL_OFFSET);
+
         iommu_feature_enable(iommu, CONTROL_CMDBUF_EN);
 
         return cmd_buf;
@@ -1074,7 +1078,8 @@ int __init amd_iommu_init(void)
                 goto free;
 
         /* IOMMU rlookup table - find the IOMMU for a specific device */
-        amd_iommu_rlookup_table = (void *)__get_free_pages(GFP_KERNEL,
+        amd_iommu_rlookup_table = (void *)__get_free_pages(
+                        GFP_KERNEL | __GFP_ZERO,
                         get_order(rlookup_table_size));
         if (amd_iommu_rlookup_table == NULL)
                 goto free;
diff --git a/arch/x86/kernel/cpu/mcheck/mce_64.c b/arch/x86/kernel/cpu/mcheck/mce_64.c
index 4b031a4ac856..1c838032fd37 100644
--- a/arch/x86/kernel/cpu/mcheck/mce_64.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_64.c
@@ -510,12 +510,9 @@ static void __cpuinit mce_cpu_features(struct cpuinfo_x86 *c)
  */
 void __cpuinit mcheck_init(struct cpuinfo_x86 *c)
 {
-        static cpumask_t mce_cpus = CPU_MASK_NONE;
-
         mce_cpu_quirks(c);
 
         if (mce_dont_init ||
-            cpu_test_and_set(smp_processor_id(), mce_cpus) ||
             !mce_available(c))
                 return;
 
diff --git a/arch/x86/kernel/microcode_core.c b/arch/x86/kernel/microcode_core.c
index 82fb2809ce32..c4b5b24e0217 100644
--- a/arch/x86/kernel/microcode_core.c
+++ b/arch/x86/kernel/microcode_core.c
@@ -272,13 +272,18 @@ static struct attribute_group mc_attr_group = {
         .name = "microcode",
 };
 
-static void microcode_fini_cpu(int cpu)
+static void __microcode_fini_cpu(int cpu)
 {
         struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
 
-        mutex_lock(&microcode_mutex);
         microcode_ops->microcode_fini_cpu(cpu);
         uci->valid = 0;
+}
+
+static void microcode_fini_cpu(int cpu)
+{
+        mutex_lock(&microcode_mutex);
+        __microcode_fini_cpu(cpu);
         mutex_unlock(&microcode_mutex);
 }
 
@@ -306,12 +311,16 @@ static int microcode_resume_cpu(int cpu)
          * to this cpu (a bit of paranoia):
          */
         if (microcode_ops->collect_cpu_info(cpu, &nsig)) {
-                microcode_fini_cpu(cpu);
+                __microcode_fini_cpu(cpu);
+                printk(KERN_ERR "failed to collect_cpu_info for resuming cpu #%d\n",
+                                cpu);
                 return -1;
         }
 
-        if (memcmp(&nsig, &uci->cpu_sig, sizeof(nsig))) {
-                microcode_fini_cpu(cpu);
+        if ((nsig.sig != uci->cpu_sig.sig) || (nsig.pf != uci->cpu_sig.pf)) {
+                __microcode_fini_cpu(cpu);
+                printk(KERN_ERR "cached ucode doesn't match the resuming cpu #%d\n",
+                                cpu);
                 /* Should we look for a new ucode here? */
                 return 1;
         }
diff --git a/arch/x86/kernel/microcode_intel.c b/arch/x86/kernel/microcode_intel.c
index 622dc4a21784..a8e62792d171 100644
--- a/arch/x86/kernel/microcode_intel.c
+++ b/arch/x86/kernel/microcode_intel.c
@@ -155,6 +155,7 @@ static DEFINE_SPINLOCK(microcode_update_lock);
 static int collect_cpu_info(int cpu_num, struct cpu_signature *csig)
 {
         struct cpuinfo_x86 *c = &cpu_data(cpu_num);
+        unsigned long flags;
         unsigned int val[2];
 
         memset(csig, 0, sizeof(*csig));
@@ -174,11 +175,16 @@ static int collect_cpu_info(int cpu_num, struct cpu_signature *csig)
                 csig->pf = 1 << ((val[1] >> 18) & 7);
         }
 
+        /* serialize access to the physical write to MSR 0x79 */
+        spin_lock_irqsave(&microcode_update_lock, flags);
+
         wrmsr(MSR_IA32_UCODE_REV, 0, 0);
         /* see notes above for revision 1.07.  Apparent chip bug */
         sync_core();
         /* get the current revision from MSR 0x8B */
         rdmsr(MSR_IA32_UCODE_REV, val[0], csig->rev);
+        spin_unlock_irqrestore(&microcode_update_lock, flags);
+
         pr_debug("microcode: collect_cpu_info : sig=0x%x, pf=0x%x, rev=0x%x\n",
                         csig->sig, csig->pf, csig->rev);
 
diff --git a/arch/x86/kernel/pci-gart_64.c b/arch/x86/kernel/pci-gart_64.c
index ba7ad83e20a8..a35eaa379ff6 100644
--- a/arch/x86/kernel/pci-gart_64.c
+++ b/arch/x86/kernel/pci-gart_64.c
@@ -745,10 +745,8 @@ void __init gart_iommu_init(void)
         unsigned long scratch;
         long i;
 
-        if (cache_k8_northbridges() < 0 || num_k8_northbridges == 0) {
-                printk(KERN_INFO "PCI-GART: No AMD GART found.\n");
+        if (cache_k8_northbridges() < 0 || num_k8_northbridges == 0)
                 return;
-        }
 
 #ifndef CONFIG_AGP_AMD64
         no_agp = 1;