On Tue, Nov 10, 2026 at 10:14:19AM +0100, Christian Brauner wrote: > With fd_async_io=1 the fileio backend calls ->read_iter() and > ->write_iter() of the backing file directly. The synchronous path goes > through vfs_iter_read() and vfs_iter_write() which check for them but > the aio path doesn't. So a backing file without them calls a NULL > pointer on its first I/O. > > Refuse such files when configuring the device. On the synchronous path > every read or write that needed the missing method failed with EINVAL > anyway.
Looks good: Reviewed-by: Christoph Hellwig <[email protected]>
