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charset="utf-8" Replace with an explicit barrier and a comment. Signed-off-by: Paolo Bonzini Reviewed-by: Stefan Hajnoczi --- util/qemu-coroutine.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/util/qemu-coroutine.c b/util/qemu-coroutine.c index 849452369201..17a88f65053e 100644 --- a/util/qemu-coroutine.c +++ b/util/qemu-coroutine.c @@ -127,9 +127,13 @@ void qemu_aio_coroutine_enter(AioContext *ctx, Corouti= ne *co) Coroutine *to =3D QSIMPLEQ_FIRST(&pending); CoroutineAction ret; =20 - /* Cannot rely on the read barrier for to in aio_co_wake(), as the= re are - * callers outside of aio_co_wake() */ - const char *scheduled =3D qatomic_mb_read(&to->scheduled); + /* + * Read to before to->scheduled; pairs with qatomic_cmpxchg in + * qemu_co_sleep(), aio_co_schedule() etc. + */ + smp_read_barrier_depends(); + + const char *scheduled =3D qatomic_read(&to->scheduled); =20 QSIMPLEQ_REMOVE_HEAD(&pending, co_queue_next); =20 --=20 2.39.2