On Wed, Dec 17, 2025 at 03:44:22PM +0100, Stefan Sperling wrote:
> On Wed, Dec 17, 2025 at 03:37:56PM +0100, Stefan Sperling wrote:
> > + if (frags > sc->sc_tx_frags || frags > sc->sc_tx_avail) {
>
> Perhaps this must check frags >= sc->sc_tx_avail to prevent the assertion
> failure in all cases.
I still have not heard from anyone about this fix. I do not use xnf myself
and I lack a test setup for it. I will drop this diff from my pending
queue soon if I don't hear anything.
And I would need an OK from another developer to commit it.
Context: https://marc.info/?l=openbsd-bugs&m=176598512119200&w=2
commit - 179a5728e367b8eca388e404a7fbcc08b887b86c
blob - 3c423aee2e37c66eb446889acb80c2dd19a4648a
file + sys/dev/pv/if_xnf.c
--- sys/dev/pv/if_xnf.c
+++ sys/dev/pv/if_xnf.c
@@ -564,11 +564,13 @@ xnf_encap(struct xnf_softc *sc, struct mbuf *m_head, u
struct mbuf *m, **next;
uint32_t oprod = *prod;
uint16_t id;
- int i, flags, n, used = 0;
+ int i, flags, n, used = 0, frags;
- if ((xnf_fragcount(m_head) > sc->sc_tx_frags) &&
- m_defrag(m_head, M_DONTWAIT))
- return (ENOBUFS);
+ frags = xnf_fragcount(m_head);
+ if (frags > sc->sc_tx_frags || frags >= sc->sc_tx_avail) {
+ if (m_defrag(m_head, M_DONTWAIT))
+ return (ENOBUFS);
+ }
flags = (sc->sc_domid << 16) | BUS_DMA_WRITE | BUS_DMA_NOWAIT;
