Re: [Qemu-devel] [PATCH VERSION 2] Disk image shared and exclusive locks.

[Kevin Wolf]

Am 07.12.2009 15:16, schrieb Richard W.M. Jones:
> Here's a second go at this patch.  The only change is that we add a
> second parameter (backinglock=none|shared|exclusive) which can be used
> to control locking on the first level (only) of backing disk.

And what about the backing file of the backing file? ;-) This approach
feels wrong somehow. We need to infer the locking for backing file from
the COW file (none => none; shared/exclusive => shared; commit acquires
an exclusive lock temporarily, but still can't prevent corruption with
turned off VMs)

You probably should add the locking flags to bdrv_open calls in
qemu-img, too.

Kevin