mm/slub: fix lockups on PREEMPT && !SMP kernels

[linux.git] / mm / slub.c

diff --git a/mm/slub.c b/mm/slub.c
index 6832c4eab104d15ff3d3bd907c92591540facf01..82c473780c9188ecf7bfc393703f47793a2fbfe9 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2449,7 +2449,8 @@ redo:
        do {
                tid = this_cpu_read(s->cpu_slab->tid);
                c = raw_cpu_ptr(s->cpu_slab);
-       } while (IS_ENABLED(CONFIG_PREEMPT) && unlikely(tid != c->tid));
+       } while (IS_ENABLED(CONFIG_PREEMPT) &&
+                unlikely(tid != READ_ONCE(c->tid)));
 
        /*
         * Irqless object alloc/free algorithm used here depends on sequence
@@ -2718,7 +2719,8 @@ redo:
        do {
                tid = this_cpu_read(s->cpu_slab->tid);
                c = raw_cpu_ptr(s->cpu_slab);
-       } while (IS_ENABLED(CONFIG_PREEMPT) && unlikely(tid != c->tid));
+       } while (IS_ENABLED(CONFIG_PREEMPT) &&
+                unlikely(tid != READ_ONCE(c->tid)));
 
        /* Same with comment on barrier() in slab_alloc_node() */
        barrier();