perf: Fix a race condition in perf_remove_from_context()

[platform/adaptation/renesas_rcar/renesas_kernel.git] / kernel / events / core.c

diff --git a/kernel/events/core.c b/kernel/events/core.c
index f774e93..3a140ca 100644 (file)
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -1516,6 +1516,11 @@ retry:
         */
        if (ctx->is_active) {
                raw_spin_unlock_irq(&ctx->lock);
+               /*
+                * Reload the task pointer, it might have been changed by
+                * a concurrent perf_event_context_sched_out().
+                */
+               task = ctx->task;
                goto retry;
        }
 
@@ -1957,6 +1962,11 @@ retry:
         */
        if (ctx->is_active) {
                raw_spin_unlock_irq(&ctx->lock);
+               /*
+                * Reload the task pointer, it might have been changed by
+                * a concurrent perf_event_context_sched_out().
+                */
+               task = ctx->task;
                goto retry;
        }