diff --git a/sys/src/9/ip/ethermedium.c b/sys/src/9/ip/ethermedium.c
index 8406542f8..36bee6bfc 100644
--- a/sys/src/9/ip/ethermedium.c
+++ b/sys/src/9/ip/ethermedium.c
@@ -200,6 +200,12 @@ etherbind(Ipifc *ifc, int argc, char **argv)
 	kproc("recvarpproc", recvarpproc, ifc);
 }
 
+/*
+ *  called from devip due to
+ *  manual unbind or from one of the reader procs
+ *  due to read error from the ethernet device.
+ *  this is called only once!
+ */
 static void
 etherunbind(Ipifc *ifc)
 {
@@ -211,18 +217,20 @@ etherunbind(Ipifc *ifc)
 	while(er->arpp == (void*)-1 || er->read4p == (void*)-1 || er->read6p == (void*)-1)
 		tsleep(&up->sleep, return0, 0, 300);
 
-	if(er->read4p != nil)
+	if(er->read4p != nil && er->read4p != up)
 		postnote(er->read4p, 1, "unbind", 0);
-	if(er->read6p != nil)
+	if(er->read6p != nil && er->read6p != up)
 		postnote(er->read6p, 1, "unbind", 0);
-	if(er->arpp != nil)
+	if(er->arpp != nil && er->arpp != up)
 		postnote(er->arpp, 1, "unbind", 0);
 	poperror();
 
 	while(waserror())
 		;
 	/* wait for readers to die */
-	while(er->arpp != nil || er->read4p != nil || er->read6p != nil)
+	while(er->arpp != nil && er->arpp != up
+	|| er->read4p != nil && er->read4p != up
+	|| er->read6p != nil && er->read6p != up)
 		tsleep(&up->sleep, return0, 0, 300);
 	poperror();
 
@@ -323,8 +331,10 @@ etherread4(void *a)
 	if(!waserror())
 	for(;;){
 		bp = devtab[er->mchan4->type]->bread(er->mchan4, ifc->maxtu, 0);
-		if(bp == nil)
+		if(bp == nil){
+			poperror();
 			break;
+		}
 		rlock(ifc);
 		if(waserror()){
 			runlock(ifc);
@@ -340,7 +350,8 @@ etherread4(void *a)
 		runlock(ifc);
 		poperror();
 	}
-	er->read4p = nil;
+	if(mediumunbindifc(ifc) != nil)
+		er->read4p = nil;	/* someone else is doing the unbind */
 	pexit("hangup", 1);
 }
 
@@ -361,8 +372,10 @@ etherread6(void *a)
 	if(!waserror())
 	for(;;){
 		bp = devtab[er->mchan6->type]->bread(er->mchan6, ifc->maxtu, 0);
-		if(bp == nil)
+		if(bp == nil){
+			poperror();
 			break;
+		}
 		rlock(ifc);
 		if(waserror()){
 			runlock(ifc);
@@ -378,7 +391,8 @@ etherread6(void *a)
 		runlock(ifc);
 		poperror();
 	}
-	er->read6p = nil;
+	if(mediumunbindifc(ifc) != nil)
+		er->read6p = nil;	/* someone else is doing the unbind */
 	pexit("hangup", 1);
 }
 
@@ -513,7 +527,7 @@ recvarp(Ipifc *ifc)
 
 	ebp = devtab[er->achan->type]->bread(er->achan, ifc->maxtu, 0);
 	if(ebp == nil)
-		return;
+		error(Ehungup);
 
 	rlock(ifc);
 
@@ -611,7 +625,8 @@ recvarpproc(void *v)
 
 	er->arpp = up;
 	if(waserror()){
-		er->arpp = nil;
+		if(mediumunbindifc(ifc) != nil)
+			er->arpp = nil;	/* someone else is doing the unbind */
 		pexit("hangup", 1);
 	}
 	for(;;)
diff --git a/sys/src/9/ip/ip.h b/sys/src/9/ip/ip.h
index 945e4e6d7..ec9cfbd35 100644
--- a/sys/src/9/ip/ip.h
+++ b/sys/src/9/ip/ip.h
@@ -741,6 +741,8 @@ extern char*	ipifcadd(Ipifc *ifc, char **argv, int argc, int tentative, Iplifc *
 extern long	ipselftabread(Fs*, char *a, ulong offset, int n);
 extern char*	ipifcadd6(Ipifc *ifc, char**argv, int argc);
 extern char*	ipifcremove6(Ipifc *ifc, char**argv, int argc);
+extern char*	mediumunbindifc(Ipifc *ifc);
+
 /*
  *  ip.c
  */
diff --git a/sys/src/9/ip/ipifc.c b/sys/src/9/ip/ipifc.c
index c79f2cc64..da899e153 100644
--- a/sys/src/9/ip/ipifc.c
+++ b/sys/src/9/ip/ipifc.c
@@ -123,6 +123,7 @@ ipfindmedium(char *name)
 
 /* same as nullmedium, to prevent unbind while bind or unbind is in progress */
 extern Medium unboundmedium;
+static char *ipifcunbindmedium(Ipifc *ifc, Medium *m);
 
 /*
  *  attach a device (or pkt driver) to the interface.
@@ -137,13 +138,12 @@ ipifcbind(Conv *c, char **argv, int argc)
 	if(argc < 2)
 		return Ebadarg;
 
-	ifc = (Ipifc*)c->ptcl;
-
 	/* bind the device to the interface */
 	m = ipfindmedium(argv[1]);
 	if(m == nil)
 		return "unknown interface type";
 
+	ifc = (Ipifc*)c->ptcl;
 	wlock(ifc);
 	if(ifc->m != nil){
 		wunlock(ifc);
@@ -151,10 +151,15 @@ ipifcbind(Conv *c, char **argv, int argc)
 	}
 	ifc->m = &unboundmedium;	/* fake until bound */
 	ifc->arg = nil;
+	if(m->unbindonclose == 0)
+		c->inuse++;
+	snprint(ifc->dev, sizeof ifc->dev, "%s%d", ifc->m->name, c->x);
 	wunlock(ifc);
 
 	if(waserror()){
 		wlock(ifc);
+		if(m->unbindonclose == 0)
+			c->inuse--;
 		ifc->m = nil;
 		wunlock(ifc);
 		nexterror();
@@ -163,6 +168,9 @@ ipifcbind(Conv *c, char **argv, int argc)
 	poperror();
 
 	wlock(ifc);
+	/* switch to the real medium */
+	ifc->m = m;
+
 	/* set the bound device name */
 	if(argc > 2)
 		strncpy(ifc->dev, argv[2], sizeof(ifc->dev));
@@ -171,12 +179,9 @@ ipifcbind(Conv *c, char **argv, int argc)
 	ifc->dev[sizeof(ifc->dev)-1] = 0;
 
 	/* set up parameters */
-	ifc->m = m;
-	ifc->maxtu = ifc->m->maxtu;
+	ifc->maxtu = m->maxtu;
 	ifc->delay = 40;
 	ifc->speed = 0;
-	if(ifc->m->unbindonclose == 0)
-		ifc->conv->inuse++;
 
 	/* default router paramters */
 	ifc->rp = c->p->f->v6p->rp;
@@ -194,25 +199,19 @@ ipifcbind(Conv *c, char **argv, int argc)
 }
 
 /*
- *  detach a device from an interface, close the interface
+ *  detach a medium from an interface, close the interface
+ *  ifc->conv is locked, ifc is wlocked
  */
 static char*
-ipifcunbind(Ipifc *ifc)
+ipifcunbindmedium(Ipifc *ifc, Medium *m)
 {
-	Medium *m;
-
-	wlock(ifc);
-	m = ifc->m;
-	if(m == nil || m == &unboundmedium){
-		wunlock(ifc);
+	if(m == nil || m == &unboundmedium)
 		return Eunbound;
-	}
 
 	/* disassociate logical interfaces */
 	while(ifc->lifc != nil)
 		ipifcremlifc(ifc, &ifc->lifc);
 
-
 	/* disassociate device */
 	if(m->unbind != nil){
 		ifc->m = &unboundmedium;	/* fake until unbound */
@@ -236,14 +235,72 @@ ipifcunbind(Ipifc *ifc)
 
 	/* dissociate routes */
 	ifc->ifcid++;
+	ifc->m = nil;
+	ifc->arg = nil;
+
 	if(m->unbindonclose == 0)
 		ifc->conv->inuse--;
-	ifc->m = nil;
-	wunlock(ifc);
 
 	return nil;
 }
 
+/*
+ *  called from Ipifcproto->unbind,
+ *  with ifc->conv locked.
+ */
+static char*
+ipifcunbind(Ipifc *ifc)
+{
+	char *err;
+
+	wlock(ifc);
+	err = ipifcunbindmedium(ifc, ifc->m);
+	wunlock(ifc);
+
+	return err;
+}
+
+/*
+ *  called from medium at any time to unbind
+ *  an interface in case of an error such as
+ *  usb ethernet being un-plugged.
+ */
+char*
+mediumunbindifc(Ipifc *ifc)
+{
+	Medium *m;
+	Conv *conv;
+	char *err;
+
+	err = Eunbound;
+
+	rlock(ifc);
+	m = ifc->m;
+	if(m == &unboundmedium){
+		runlock(ifc);
+		return err;
+	}
+	conv = ifc->conv;
+	runlock(ifc);
+
+	assert(conv != nil);
+	assert(m != nil);
+	assert(m->unbindonclose == 0);
+
+	qlock(conv);
+
+	assert(conv->inuse > 0);
+	assert((Ipifc*)conv->ptcl == ifc);
+
+	wlock(ifc);
+	if(ifc->m == m)
+		err = ipifcunbindmedium(ifc, m);
+	wunlock(ifc);
+	qunlock(conv);
+
+	return err;
+}
+
 char sfixedformat[] = "device %s maxtu %d sendra %d recvra %d mflag %d oflag %d"
 " maxraint %d minraint %d linkmtu %d reachtime %d rxmitra %d ttl %d routerlt %d"
 " pktin %lud pktout %lud errin %lud errout %lud speed %d delay %d\n";
diff --git a/sys/src/9/ip/netdevmedium.c b/sys/src/9/ip/netdevmedium.c
index 9ad95b40e..bcf3e5b54 100644
--- a/sys/src/9/ip/netdevmedium.c
+++ b/sys/src/9/ip/netdevmedium.c
@@ -68,14 +68,14 @@ netdevunbind(Ipifc *ifc)
 	while(er->readp == (void*)-1)
 		tsleep(&up->sleep, return0, 0, 300);
 
-	if(er->readp != nil)
+	if(er->readp != nil && er->readp != up)
 		postnote(er->readp, 1, "unbind", 0);
 	poperror();
 
 	while(waserror())
 		;
 	/* wait for reader to die */
-	while(er->readp != nil)
+	while(er->readp != nil && er->readp != up)
 		tsleep(&up->sleep, return0, 0, 300);
 	poperror();
 
@@ -115,10 +115,6 @@ netdevread(void *a)
 		bp = devtab[er->mchan->type]->bread(er->mchan, ifc->maxtu, 0);
 		if(bp == nil){
 			poperror();
-			if(!waserror()){
-				static char *argv[]  = { "unbind" };
-				ifc->conv->p->ctl(ifc->conv, argv, 1);
-			}
 			break;
 		}
 		rlock(ifc);
@@ -134,7 +130,8 @@ netdevread(void *a)
 		runlock(ifc);
 		poperror();
 	}
-	er->readp = nil;
+	if(mediumunbindifc(ifc) != nil)
+		er->readp = nil;	/* someone else is doing the unbind */
 	pexit("hangup", 1);
 }