The smp_mb() in cpuhp_thread_fun() appears to be misplaced, and
need to be after the load of st->should_run, to prevent
reordering of the later load/stores w.r.t. the load of
st->should_run.

Signed-off-by: Neeraj Upadhyay <neer...@codeaurora.org>
---
 kernel/cpu.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/cpu.c b/kernel/cpu.c
index aa7fe85..eb4041f 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -607,15 +607,15 @@ static void cpuhp_thread_fun(unsigned int cpu)
        bool bringup = st->bringup;
        enum cpuhp_state state;
 
+       if (WARN_ON_ONCE(!st->should_run))
+               return;
+
        /*
         * ACQUIRE for the cpuhp_should_run() load of ->should_run. Ensures
         * that if we see ->should_run we also see the rest of the state.
         */
        smp_mb();
 
-       if (WARN_ON_ONCE(!st->should_run))
-               return;
-
        cpuhp_lock_acquire(bringup);
 
        if (st->single) {
-- 
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