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Date: Fri,  7 Oct 2022 15:23:57 +0300
From: Alexey Izbyshev <>
Subject: [PATCH] fix use of uninitialized dummy_fut in aio_suspend

aio_suspend waits on a dummy futex in the corner case when the array of
requests contains NULL pointers only. But the value of this futex was
left uninitialized, so if it happens to be non-zero, aio_suspend
degrades to spinning instead of blocking.
 src/aio/aio_suspend.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/aio/aio_suspend.c b/src/aio/aio_suspend.c
index 1c1060e3..290b43f2 100644
--- a/src/aio/aio_suspend.c
+++ b/src/aio/aio_suspend.c
@@ -9,7 +9,7 @@ int aio_suspend(const struct aiocb *const cbs[], int cnt, const struct timespec
 	int i, tid = 0, ret, expect = 0;
 	struct timespec at;
-	volatile int dummy_fut, *pfut;
+	volatile int dummy_fut = 0, *pfut;
 	int nzcnt = 0;
 	const struct aiocb *cb = 0;

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