1 files changed, 22 insertions, 4 deletions

diff --git a/arch/x86/lib/msr.c b/arch/x86/lib/msr.c
index 41628b104b9e..872834177937 100644
--- a/arch/x86/lib/msr.c
+++ b/arch/x86/lib/msr.c
@@ -7,7 +7,6 @@ struct msr_info {
         u32 msr_no;
         struct msr reg;
         struct msr *msrs;
-        int off;
         int err;
 };
 
@@ -18,7 +17,7 @@ static void __rdmsr_on_cpu(void *info)
         int this_cpu = raw_smp_processor_id();
 
         if (rv->msrs)
-                reg = &rv->msrs[this_cpu - rv->off];
+                reg = per_cpu_ptr(rv->msrs, this_cpu);
         else
                 reg = &rv->reg;
 
@@ -32,7 +31,7 @@ static void __wrmsr_on_cpu(void *info)
         int this_cpu = raw_smp_processor_id();
 
         if (rv->msrs)
-                reg = &rv->msrs[this_cpu - rv->off];
+                reg = per_cpu_ptr(rv->msrs, this_cpu);
         else
                 reg = &rv->reg;
 
@@ -80,7 +79,6 @@ static void __rwmsr_on_cpus(const struct cpumask *mask, u32 msr_no,
 
         memset(&rv, 0, sizeof(rv));
 
-        rv.off    = cpumask_first(mask);
         rv.msrs   = msrs;
         rv.msr_no = msr_no;
 
@@ -120,6 +118,26 @@ void wrmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr *msrs)
 }
 EXPORT_SYMBOL(wrmsr_on_cpus);
 
+struct msr *msrs_alloc(void)
+{
+        struct msr *msrs = NULL;
+
+        msrs = alloc_percpu(struct msr);
+        if (!msrs) {
+                pr_warning("%s: error allocating msrs\n", __func__);
+                return NULL;
+        }
+
+        return msrs;
+}
+EXPORT_SYMBOL(msrs_alloc);
+
+void msrs_free(struct msr *msrs)
+{
+        free_percpu(msrs);
+}
+EXPORT_SYMBOL(msrs_free);
+
 /* These "safe" variants are slower and should be used when the target MSR
    may not actually exist. */
 static void __rdmsr_safe_on_cpu(void *info)