Re: [Qemu-devel] [PATCH v2 4/7] block: take lock around bdrv_read implementations

[Avi Kivity]

On 10/20/2011 01:16 PM, Paolo Bonzini wrote:
> This does the first part of the conversion to coroutines, by
> wrapping bdrv_read implementations to take the read side of the
> rwlock.
>
> Drivers that implement bdrv_read rather than bdrv_co_readv can
> then benefit from asynchronous operation (at least if the underlying
> protocol supports it, which is not the case for raw-win32), even
> though they still operate with a bounce buffer.
>
> raw-win32 does not need the lock, because it cannot yield.
> nbd also doesn't probably, but better be safe.

This patch (2914caa088e3fbbd) breaks autotest when a guest reboots after
install; instead of rebooting, the guest is stuck in the bootloader or
kernel.

This was discovered in qemu-kvm, but applies to plain qemu too.  The
commit above is broken, it's parent is good.

-- 
error compiling committee.c: too many arguments to function