On 08.08.26 07:52, Connor Kite wrote:
On Mon, Aug 3, 2026 at 5:56 AM Hanna Czenczek <[email protected]> wrote:
It’s not immediately obvious what is ensuring that `iov_len` can never
be 0. Sure, it would be wrong and makes no sense, but that is why I
think an `assert(iovec[i].iov_len > 0)` would be appropriate.
(Looks like `virtqueue_map_desc()` is what rejects zero length, but that
is not really local to this code path, so not immediately obvious.)
Hanna
From the QEMU Coding Style guidelines on error-handling it looks like
errors that
could be initiated by a malfunctioning guest should not cause Qemu to
exit. Would it be
more appropriate to return false when zero-length is detected? That follows
the existing error path returning up to vhost_handle_guest_kick, which
renders the svq
unresponsive to future kicks.
Sure, but it’s necessary only *if* a malfunctioning guest could cause
this. As I said, it looks like `virtqueue_map_desc()` already rejects
zero-length descriptors, so an assert should be sufficient.
Then again, if you can handle it benignly either way (without an
assert), that’s always a good option.
Hanna
