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Date: Tue, 6 Mar 2018 12:08:44 +0100
From: Kevin Wolf <kwolf@redhat.com>
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References: <20180306105354.15197-1-stefanha@redhat.com>
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In-Reply-To: <20180306105354.15197-1-stefanha@redhat.com>
Subject: Re: [Qemu-devel] [PATCH] block: make BDRV_POLL_WHILE() re-entrancy
 safe
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To: Stefan Hajnoczi <stefanha@redhat.com>
Cc: qemu-devel@nongnu.org, Paolo Bonzini <pbonzini@redhat.com>, "fuweiwei (C)" <fuweiwei2@huawei.com>, Max Reitz <mreitz@redhat.com>, qemu-block@nongnu.org

Am 06.03.2018 um 11:53 hat Stefan Hajnoczi geschrieben:
> Nested BDRV_POLL_WHILE() calls can occur.  Currently
> assert(!bs_->wakeup) will fail when this happens.
> 
> This patch converts bs->wakeup from bool to a counter.
> 
> Nesting works correctly because outer BDRV_POLL_WHILE() callers evaluate
> the condition again after the inner caller completes (invoking the inner
> caller counts as aio_poll() progress).
> 
> Reported-by: "fuweiwei (C)" <fuweiwei2@huawei.com>
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Doesn't this conflict with your own AIO_WAIT_WHILE() patch?

Kevin