Module Name: src
Committed By: riastradh
Date: Thu Mar 3 05:48:37 UTC 2022
Modified Files:
src/sys/dev/usb: usbnet.c
Log Message:
usbnet: Refuse to bring interfaces back up once dying.
Make this happen uniformly across all usbnet drivers, not on a
per-driver basis.
This ensures new activity on the interface can't happen by the time
we have stopped existing activity and waited for it to complete.
To generate a diff of this commit:
cvs rdiff -u -r1.57 -r1.58 src/sys/dev/usb/usbnet.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/usb/usbnet.c
diff -u src/sys/dev/usb/usbnet.c:1.57 src/sys/dev/usb/usbnet.c:1.58
--- src/sys/dev/usb/usbnet.c:1.57 Thu Mar 3 05:48:30 2022
+++ src/sys/dev/usb/usbnet.c Thu Mar 3 05:48:37 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: usbnet.c,v 1.57 2022/03/03 05:48:30 riastradh Exp $ */
+/* $NetBSD: usbnet.c,v 1.58 2022/03/03 05:48:37 riastradh Exp $ */
/*
* Copyright (c) 2019 Matthew R. Green
@@ -31,7 +31,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: usbnet.c,v 1.57 2022/03/03 05:48:30 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: usbnet.c,v 1.58 2022/03/03 05:48:37 riastradh Exp $");
#include <sys/param.h>
#include <sys/kernel.h>
@@ -1289,9 +1289,20 @@ usbnet_if_init(struct ifnet *ifp)
{
USBNETHIST_FUNC(); USBNETHIST_CALLED();
struct usbnet * const un = ifp->if_softc;
+ bool dying;
KASSERTMSG(IFNET_LOCKED(ifp), "%s", ifp->if_xname);
+ /*
+ * Prevent anyone from bringing the interface back up once
+ * we're detaching.
+ */
+ mutex_enter(&un->un_pri->unp_core_lock);
+ dying = un->un_pri->unp_dying;
+ mutex_exit(&un->un_pri->unp_core_lock);
+ if (dying)
+ return EIO;
+
return uno_init(un, ifp);
}
@@ -1572,10 +1583,18 @@ usbnet_detach(device_t self, int flags)
struct ifnet * const ifp = usbnet_ifp(un);
struct mii_data * const mii = usbnet_mii(un);
+ /*
+ * Prevent new activity. After we stop the interface, it
+ * cannot be brought back up.
+ */
mutex_enter(&unp->unp_core_lock);
unp->unp_dying = true;
mutex_exit(&unp->unp_core_lock);
+ /*
+ * If we're still running on the network, stop and wait for all
+ * asynchronous activity to finish.
+ */
IFNET_LOCK(ifp);
if (ifp->if_flags & IFF_RUNNING) {
usbnet_if_stop(ifp, 1);
