1 files changed, 18 insertions, 15 deletions

diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c
index 8156e47da7ba..18c25ab28557 100644
--- a/arch/x86/events/intel/ds.c
+++ b/arch/x86/events/intel/ds.c
@@ -372,10 +372,9 @@ static int alloc_pebs_buffer(int cpu)
 static void release_pebs_buffer(int cpu)
 {
         struct cpu_hw_events *hwev = per_cpu_ptr(&cpu_hw_events, cpu);
-        struct debug_store *ds = hwev->ds;
         void *cea;
 
-        if (!ds || !x86_pmu.pebs)
+        if (!x86_pmu.pebs)
                 return;
 
         kfree(per_cpu(insn_buffer, cpu));
@@ -384,7 +383,6 @@ static void release_pebs_buffer(int cpu)
         /* Clear the fixmap */
         cea = &get_cpu_entry_area(cpu)->cpu_debug_buffers.pebs_buffer;
         ds_clear_cea(cea, x86_pmu.pebs_buffer_size);
-        ds->pebs_buffer_base = 0;
         dsfree_pages(hwev->ds_pebs_vaddr, x86_pmu.pebs_buffer_size);
         hwev->ds_pebs_vaddr = NULL;
 }
@@ -419,16 +417,14 @@ static int alloc_bts_buffer(int cpu)
 static void release_bts_buffer(int cpu)
 {
         struct cpu_hw_events *hwev = per_cpu_ptr(&cpu_hw_events, cpu);
-        struct debug_store *ds = hwev->ds;
         void *cea;
 
-        if (!ds || !x86_pmu.bts)
+        if (!x86_pmu.bts)
                 return;
 
         /* Clear the fixmap */
         cea = &get_cpu_entry_area(cpu)->cpu_debug_buffers.bts_buffer;
         ds_clear_cea(cea, BTS_BUFFER_SIZE);
-        ds->bts_buffer_base = 0;
         dsfree_pages(hwev->ds_bts_vaddr, BTS_BUFFER_SIZE);
         hwev->ds_bts_vaddr = NULL;
 }
@@ -454,16 +450,22 @@ void release_ds_buffers(void)
         if (!x86_pmu.bts && !x86_pmu.pebs)
                 return;
 
-        get_online_cpus();
-        for_each_online_cpu(cpu)
+        for_each_possible_cpu(cpu)
+                release_ds_buffer(cpu);
+
+        for_each_possible_cpu(cpu) {
+                /*
+                 * Again, ignore errors from offline CPUs, they will no longer
+                 * observe cpu_hw_events.ds and not program the DS_AREA when
+                 * they come up.
+                 */
                 fini_debug_store_on_cpu(cpu);
+        }
 
         for_each_possible_cpu(cpu) {
                 release_pebs_buffer(cpu);
                 release_bts_buffer(cpu);
-                release_ds_buffer(cpu);
         }
-        put_online_cpus();
 }
 
 void reserve_ds_buffers(void)
@@ -483,8 +485,6 @@ void reserve_ds_buffers(void)
         if (!x86_pmu.pebs)
                 pebs_err = 1;
 
-        get_online_cpus();
-
         for_each_possible_cpu(cpu) {
                 if (alloc_ds_buffer(cpu)) {
                         bts_err = 1;
@@ -521,11 +521,14 @@ void reserve_ds_buffers(void)
                 if (x86_pmu.pebs && !pebs_err)
                         x86_pmu.pebs_active = 1;
 
-                for_each_online_cpu(cpu)
+                for_each_possible_cpu(cpu) {
+                        /*
+                         * Ignores wrmsr_on_cpu() errors for offline CPUs they
+                         * will get this call through intel_pmu_cpu_starting().
+                         */
                         init_debug_store_on_cpu(cpu);
+                }
         }
-
-        put_online_cpus();
 }
 
 /*