As long as BDRV_O_INCOMING is set, the image file is only opened so we have a file descriptor for it. We're definitely not supposed to modify the image, it's still owned by the migration source.
Signed-off-by: Kevin Wolf <kw...@redhat.com> --- block/io.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/block/io.c b/block/io.c index 841f5b5..e893be8 100644 --- a/block/io.c +++ b/block/io.c @@ -1293,6 +1293,7 @@ static int coroutine_fn bdrv_co_do_pwritev(BlockDriverState *bs, if (bs->read_only) { return -EPERM; } + assert(!(bs->open_flags & BDRV_O_INCOMING)); ret = bdrv_check_byte_request(bs, offset, bytes); if (ret < 0) { @@ -2453,6 +2454,7 @@ int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num, } else if (bs->read_only) { return -EPERM; } + assert(!(bs->open_flags & BDRV_O_INCOMING)); /* Do nothing if disabled. */ if (!(bs->open_flags & BDRV_O_UNMAP)) { -- 1.8.3.1