Re: [Qemu-devel] [PATCH 19/19] block: make accounting thread-safe

[Alberto Garcia]

On Mon 05 Jun 2017 02:39:08 PM CEST, Paolo Bonzini wrote:
> @@ -102,6 +107,8 @@ static void block_account_one_io(BlockAcctStats *stats, 
> BlockAcctCookie *cookie,
>  
>      assert(cookie->type < BLOCK_MAX_IOTYPE);
>  
> +    qemu_mutex_lock(&stats->lock);

QEMU crashes because this lock is not initialized if you do aio_read
directly from a BDS not attached to a BlockBackend (should that
operation be legal at all?)

$ qemu-system-x86_64 -monitor stdio \
-blockdev driver=qcow2,file.driver=file,file.filename=hd0.img,node-name=hd0

(qemu) qemu-io hd0 "aio_read 0 1M"
qemu-system-x86_64: util/qemu-thread-posix.c:64: qemu_mutex_lock_impl: 
Assertion `mutex->initialized' failed.
Aborted

Berto