Stefan Weil wrote: > This command used to work, but fails now: > > $ i386-softmmu/qemu -snapshot /dev/sda > qemu: could not open disk image /dev/sda: Permission denied > > $ ls -l /dev/sda > brw-rw-r-- 1 root disk 8, 0 13. Feb 08:55 /dev/sda > > The original file of a snapshot needs only read access, > but QEMU tries read/write access and fails. > > Variants of above command using -hda or -drive > also fail with the same error message. > > I did not test whether the regression affects other > kinds of images, too. Maybe only raw images trigger > no longer work. > > Regards > Stefan Weil > > >
Sorry for the late reply, this is my fault. It will fail for any image format. It's already fixed with commit 4dca4b639cb20fee38f6eec0a391aecc0ad8848d : "block: more read-only changes, related to backing files" Now, since the /dev/sda is the backing-file, it's opened as read-only, no permission problem. Notice that if you try to commit your changes to the read-only disk (in monitor command), it will be silently ignored, no error or warning displayed. Should I add a warning/error printing ? Naphtali
