On Tue, Apr 25, 2017 at 11:13:17PM +0800, Fam Zheng wrote: > Hi Kevin, > > This happens both on master and on your block-next tree: > > $ qemu-io -f raw null-co:// -c 'reopen -r' > Unexpected error in bdrv_check_perm() at /stor/work/qemu/block.c:1437: > Block node is read-only > Aborted > > It seems bs->read_only and perms go out of sync when bdrv_reopen() > toggles the former.
It seems that the problem started in 8ee039951dea9a809e4745c42aebb4a7. I just took a quick look at the code, but one difference is that after this change bdrv_check_perm(old_bs, ...) is called before QLIST_REMOVE(child, next_parent), so the returned perms are likely different. Berto