From: Chris Mason

While testing fsaio here, I hit an oops in kick_iocb because iocb->mm
was null.  This was right as the program was exiting.

With the patch below, I wasn't able to reproduce, it makes sure we flush
the workqueue every time __put_ioctx gets called.


Index: linux.t/fs/aio.c

diff -upN reference/fs/aio.c current/fs/aio.c
--- reference/fs/aio.c	2004-04-09 13:23:20.000000000 -0700
+++ current/fs/aio.c	2004-04-09 13:23:20.000000000 -0700
@@ -375,6 +375,7 @@ void fastcall __put_ioctx(struct kioctx 
 	if (unlikely(ctx->reqs_active))
 		BUG();
 
+	flush_workqueue(aio_wq);
 	aio_free_ring(ctx);
 	mmdrop(ctx->mm);
 	ctx->mm = NULL;
@@ -1219,11 +1220,6 @@ static void io_destroy(struct kioctx *io
 
 	aio_cancel_all(ioctx);
 	wait_for_all_aios(ioctx);
-	/*
-	 * this is an overkill, but ensures we don't leave
-	 * the ctx on the aio_wq
-	 */
-	flush_workqueue(aio_wq);
 	put_ioctx(ioctx);	/* once for the lookup */
 }