From: patrick <patrick@openbsd.org>
Date: Wed, 5 Jul 2023 18:11:08 +0000 (+0000)
Subject: Fix off-by-one in the MSI-X interrupt establish loop that always tried to
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=de3309eee246ab22f714794c6ed0d90cabe5acc6;p=openbsd

Fix off-by-one in the MSI-X interrupt establish loop that always tried to
establish one more interrupt than would be needed for per-VQ IRQs. This
meant even though there were enough MSI-X vectors available this path could
fail, roll back previously established interrupts and switch to shared IRQs
as a fallback.

ok dv@
---

diff --git a/sys/dev/pci/virtio_pci.c b/sys/dev/pci/virtio_pci.c
index 1e543983466..28087f1ac9d 100644
--- a/sys/dev/pci/virtio_pci.c
+++ b/sys/dev/pci/virtio_pci.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: virtio_pci.c,v 1.33 2023/05/29 08:13:35 sf Exp $	*/
+/*	$OpenBSD: virtio_pci.c,v 1.34 2023/07/05 18:11:08 patrick Exp $	*/
 /*	$NetBSD: virtio.c,v 1.3 2011/11/02 23:05:52 njoly Exp $	*/
 
 /*
@@ -976,7 +976,7 @@ virtio_pci_setup_msix(struct virtio_pci_softc *sc, struct pci_attach_args *pa,
 		for (i = 0; i < vsc->sc_nvqs; i++)
 			virtio_pci_set_msix_queue_vector(sc, i, 1);
 	} else {
-		for (i = 0; i <= vsc->sc_nvqs; i++) {
+		for (i = 0; i < vsc->sc_nvqs; i++) {
 			if (virtio_pci_msix_establish(sc, pa, i + 1,
 			    virtio_pci_queue_intr, &vsc->sc_vqs[i])) {
 				goto fail;