Am 22.05.2019 um 19:03 hat Max Reitz geschrieben: > Hi, > > This series is mainly a fix for > https://bugzilla.redhat.com/show_bug.cgi?id=1703793. The problem > described there is that mirroring to a gluster volume, then switching > off the volume makes qemu crash. There are two problems here: > > (1) file-posix reopens the FD all the time because it thinks the FD it > has is RDONLY. It actually isn’t after the first reopen, we just > forgot to change the internal flags. That’s what patch 1 is for. > > (2) Even then, when mirror completes, it drops its write permission on > the FD. This requires a reopen, which will fail if the volume is > down. Mirror doesn’t expect that. Nobody ever expects that > dropping permissions can fail, and rightfully so because that’s what > I think we have generally agreed on. > Therefore, the block layer should hide this error. This is what the > last two patches are for. > > The penultimate patch adds two assertions: bdrv_replace_child() (for the > old BDS) and bdrv_inactivate_recurse() assume they only ever drop > assertions. This is now substantiated by these new assertions. > It turns out that this assumption was just plain wrong. Patches 3 to 5 > make it right.
Thanks, applied to the block branch. Kevin
