Author: kp Date: Wed Jan 25 21:25:26 2017 New Revision: 312782 URL: https://svnweb.freebsd.org/changeset/base/312782
Log: bridge: Release the bridge lock when calling bridge_set_ifcap() This calls ioctl() handlers for the different interfaces in the bridge. These handlers expect to get called in an ioctl context where it's safe for them to sleep. We may not sleep with the bridge lock held. However, we still need to protect the interface list, to ensure it doesn't get changed while we iterate over it. Use BRIDGE_XLOCK(), which prevents bridge members from being removed. Adding bridge members is safe, because it uses LIST_INSERT_HEAD(). This caused panics when adding xen interfaces to a bridge. PR: 216304 Reviewed by: ae MFC after: 1 week Sponsored by: RootBSD Differential Revision: https://reviews.freebsd.org/D9290 Modified: head/sys/net/if_bridge.c head/sys/net/if_bridgevar.h Modified: head/sys/net/if_bridge.c ============================================================================== --- head/sys/net/if_bridge.c Wed Jan 25 21:05:48 2017 (r312781) +++ head/sys/net/if_bridge.c Wed Jan 25 21:25:26 2017 (r312782) @@ -909,14 +909,18 @@ bridge_mutecaps(struct bridge_softc *sc) mask &= bif->bif_savedcaps; } + BRIDGE_XLOCK(sc); LIST_FOREACH(bif, &sc->sc_iflist, bif_next) { enabled = bif->bif_ifp->if_capenable; enabled &= ~BRIDGE_IFCAPS_STRIP; /* strip off mask bits and enable them again if allowed */ enabled &= ~BRIDGE_IFCAPS_MASK; enabled |= mask; + BRIDGE_UNLOCK(sc); bridge_set_ifcap(sc, bif, enabled); + BRIDGE_LOCK(sc); } + BRIDGE_XDROP(sc); } @@ -927,6 +931,8 @@ bridge_set_ifcap(struct bridge_softc *sc struct ifreq ifr; int error; + BRIDGE_UNLOCK_ASSERT(sc); + bzero(&ifr, sizeof(ifr)); ifr.ifr_reqcap = set; Modified: head/sys/net/if_bridgevar.h ============================================================================== --- head/sys/net/if_bridgevar.h Wed Jan 25 21:05:48 2017 (r312781) +++ head/sys/net/if_bridgevar.h Wed Jan 25 21:25:26 2017 (r312782) @@ -280,6 +280,7 @@ struct ifbpstpconf { #define BRIDGE_LOCK(_sc) mtx_lock(&(_sc)->sc_mtx) #define BRIDGE_UNLOCK(_sc) mtx_unlock(&(_sc)->sc_mtx) #define BRIDGE_LOCK_ASSERT(_sc) mtx_assert(&(_sc)->sc_mtx, MA_OWNED) +#define BRIDGE_UNLOCK_ASSERT(_sc) mtx_assert(&(_sc)->sc_mtx, MA_NOTOWNED) #define BRIDGE_LOCK2REF(_sc, _err) do { \ mtx_assert(&(_sc)->sc_mtx, MA_OWNED); \ if ((_sc)->sc_iflist_xcnt > 0) \ _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
