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From: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <5655B706.6060306@redhat.com>
Date: Wed, 25 Nov 2015 14:26:30 +0100
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Subject: Re: [Qemu-devel] [PATCH v2] qemu_mutex_iothread_locked not
	correctly synchronized
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To: David Engraf <david.engraf@sysgo.com>, qemu-devel@nongnu.org
Cc: Fam Zheng <famz@redhat.com>



On 25/11/2015 13:31, David Engraf wrote:
> Hi Paolo,
> 
> please check the new version. I removed changing the iothread_locked
> variable. But I still need to set the correct value of iothread_locked
> when using qemu_cond_wait. 

No, you don't.  Who is reading iothread_locked during
qemu_cond_wait_iothread?  No one, because it is a thread-local variable
whose address is never taken.

Paolo

> +static void qemu_cond_wait_iothread(QemuCond *cond)
> +{
> +    iothread_locked = false;
> +    qemu_cond_wait(cond, &qemu_global_mutex);
> +    iothread_locked = true;
> +}