Merge commit 'v2.6.37-rc5' into perf/core

Merge reason: Pick up the latest -rc.

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

1 files changed, 23 insertions, 2 deletions

diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index 194539aea175..c1c52c341f40 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -44,6 +44,8 @@ static u64 gru_start_paddr, gru_end_paddr;
 static union uvh_apicid uvh_apicid;
 int uv_min_hub_revision_id;
 EXPORT_SYMBOL_GPL(uv_min_hub_revision_id);
+unsigned int uv_apicid_hibits;
+EXPORT_SYMBOL_GPL(uv_apicid_hibits);
 static DEFINE_SPINLOCK(uv_nmi_lock);
 
 static inline bool is_GRU_range(u64 start, u64 end)
@@ -85,6 +87,23 @@ static void __init early_get_apic_pnode_shift(void)
                 uvh_apicid.s.pnode_shift = UV_APIC_PNODE_SHIFT;
 }
 
+/*
+ * Add an extra bit as dictated by bios to the destination apicid of
+ * interrupts potentially passing through the UV HUB.  This prevents
+ * a deadlock between interrupts and IO port operations.
+ */
+static void __init uv_set_apicid_hibit(void)
+{
+        union uvh_lb_target_physical_apic_id_mask_u apicid_mask;
+        unsigned long *mmr;
+
+        mmr = early_ioremap(UV_LOCAL_MMR_BASE |
+                UVH_LB_TARGET_PHYSICAL_APIC_ID_MASK, sizeof(*mmr));
+        apicid_mask.v = *mmr;
+        early_iounmap(mmr, sizeof(*mmr));
+        uv_apicid_hibits = apicid_mask.s.bit_enables & UV_APICID_HIBIT_MASK;
+}
+
 static int __init uv_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
 {
         int nodeid;
@@ -102,6 +121,7 @@ static int __init uv_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
                         __get_cpu_var(x2apic_extra_bits) =
                                 nodeid << (uvh_apicid.s.pnode_shift - 1);
                         uv_system_type = UV_NON_UNIQUE_APIC;
+                        uv_set_apicid_hibit();
                         return 1;
                 }
         }
@@ -155,6 +175,7 @@ static int __cpuinit uv_wakeup_secondary(int phys_apicid, unsigned long start_ri
         int pnode;
 
         pnode = uv_apicid_to_pnode(phys_apicid);
+        phys_apicid |= uv_apicid_hibits;
         val = (1UL << UVH_IPI_INT_SEND_SHFT) |
             (phys_apicid << UVH_IPI_INT_APIC_ID_SHFT) |
             ((start_rip << UVH_IPI_INT_VECTOR_SHFT) >> 12) |
@@ -236,7 +257,7 @@ static unsigned int uv_cpu_mask_to_apicid(const struct cpumask *cpumask)
         int cpu = cpumask_first(cpumask);
 
         if ((unsigned)cpu < nr_cpu_ids)
-                return per_cpu(x86_cpu_to_apicid, cpu);
+                return per_cpu(x86_cpu_to_apicid, cpu) | uv_apicid_hibits;
         else
                 return BAD_APICID;
 }
@@ -255,7 +276,7 @@ uv_cpu_mask_to_apicid_and(const struct cpumask *cpumask,
                 if (cpumask_test_cpu(cpu, cpu_online_mask))
                         break;
         }
-        return per_cpu(x86_cpu_to_apicid, cpu);
+        return per_cpu(x86_cpu_to_apicid, cpu) | uv_apicid_hibits;
 }
 
 static unsigned int x2apic_get_apic_id(unsigned long x)