From: sf <sf@openbsd.org>
Date: Sat, 2 Dec 2023 10:01:35 +0000 (+0000)
Subject: virtio: Fix handling of feature bits >= 32
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=c0ea3bd1e6801244e065cf90f8a4247feb3cf3d6;p=openbsd

virtio: Fix handling of feature bits >= 32

Fix handling of feature bits >= 32.  This does not yet affect any driver
as no high feature bit besides VERSION_1 is used, and that one has
special handling.

Also, with VIRTIO_DEBUG, simply walk through all transport and device
feature names, so that we don't need to adjust the if clause whenever
the standard introduces new transport features.

ok jan@ bluhm@
---

diff --git a/sys/dev/pv/virtio.c b/sys/dev/pv/virtio.c
index e9be61c0bbe..53e27e27211 100644
--- a/sys/dev/pv/virtio.c
+++ b/sys/dev/pv/virtio.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: virtio.c,v 1.23 2023/07/07 10:23:39 patrick Exp $	*/
+/*	$OpenBSD: virtio.c,v 1.24 2023/12/02 10:01:35 sf Exp $	*/
 /*	$NetBSD: virtio.c,v 1.3 2011/11/02 23:05:52 njoly Exp $	*/
 
 /*
@@ -97,7 +97,7 @@ virtio_log_features(uint64_t host, uint64_t neg,
 	const struct virtio_feature_name *namep;
 	int i;
 	char c;
-	uint32_t bit;
+	uint64_t bit;
 
 	for (i = 0; i < 64; i++) {
 		if (i == 30) {
@@ -107,13 +107,17 @@ virtio_log_features(uint64_t host, uint64_t neg,
 			 */
 			continue;
 		}
-		bit = 1 << i;
+		bit = 1ULL << i;
 		if ((host&bit) == 0)
 			continue;
-		namep = (i < 24 || i > 37) ? guest_feature_names :
-		    transport_feature_names;
+		namep = guest_feature_names;
 		while (namep->bit && namep->bit != bit)
 			namep++;
+		if (namep->name == NULL) {
+			namep = transport_feature_names;
+			while (namep->bit && namep->bit != bit)
+				namep++;
+		}
 		c = (neg&bit) ? '+' : '-';
 		if (namep->name)
 			printf(" %c%s", c, namep->name);
diff --git a/sys/dev/pv/virtiovar.h b/sys/dev/pv/virtiovar.h
index 7f2aea701cd..d12cb2c59b8 100644
--- a/sys/dev/pv/virtiovar.h
+++ b/sys/dev/pv/virtiovar.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: virtiovar.h,v 1.15 2023/07/07 10:23:39 patrick Exp $	*/
+/*	$OpenBSD: virtiovar.h,v 1.16 2023/12/02 10:01:35 sf Exp $	*/
 /*	$NetBSD: virtiovar.h,v 1.1 2011/10/30 12:12:21 hannken Exp $	*/
 
 /*
@@ -138,7 +138,7 @@ struct virtqueue {
 };
 
 struct virtio_feature_name {
-	uint32_t	 bit;
+	uint64_t	 bit;
 	const char	*name;
 };
 
@@ -203,7 +203,7 @@ struct virtio_softc {
 #define	virtio_device_reset(sc)			virtio_set_status((sc), 0)
 
 static inline int
-virtio_has_feature(struct virtio_softc *sc, unsigned int fbit)
+virtio_has_feature(struct virtio_softc *sc, uint64_t fbit)
 {
 	if (sc->sc_active_features & fbit)
 		return 1;