[Bug 1865048] Re: qemu-img --force-share does not disable file locking

2020-02-28 Thread Max Reitz
Hi Olaf, Every “node” in the block graph corresponds to some driver. A driver can be a protocol or a format driver (or a filter driver, but that isn’t important here). In your example, there is only a single node, for a protocol driver (namely “file”). You need a format driver node on top to in

[Bug 1865048] Re: qemu-img --force-share does not disable file locking

2020-02-28 Thread Olaf Seibert
Hi Maz, thanks for the information! The situation we're in is where we are suspecting the file locking on a shared network file system to be broken, so we were looking for ways to avoid any locking. I had tried some variations on your image-opts style invocation, but did not find any variant wher

[Bug 1865048] Re: qemu-img --force-share does not disable file locking

2020-02-27 Thread Max Reitz
Hi, That’s intentional. The man page says this: --force-share (-U) If specified, "qemu-img" will open the image in shared mode, allowing other QEMU processes to open it in write mode. For example, this can be used to get the image information (with