On Mon, 21 May 2018 08:34:10 +0000 Matt Macy <mm...@freebsd.org> wrote:
> Author: mmacy > Date: Mon May 21 08:34:10 2018 > New Revision: 333968 > URL: https://svnweb.freebsd.org/changeset/base/333968 > > Log: > in(6)_mcast: Expand out vnet set / restore macro so that they work > in a conditional block > Reported by: zec at fer.hr > > Modified: > head/sys/netinet/in_mcast.c > head/sys/netinet6/in6_mcast.c > > Modified: head/sys/netinet/in_mcast.c > ============================================================================== > --- head/sys/netinet/in_mcast.c Mon May 21 07:12:06 > 2018 (r333967) +++ head/sys/netinet/in_mcast.c Mon May > 21 08:34:10 2018 (r333968) @@ -653,6 +653,7 @@ > inm_release(struct in_multi *inm) { > struct ifmultiaddr *ifma; > struct ifnet *ifp; > + struct vnet *saved_vnet; > > CTR2(KTR_IGMPV3, "%s: refcount is %d", __func__, > inm->inm_refcount); MPASS(inm->inm_refcount == 0); > @@ -663,14 +664,16 @@ inm_release(struct in_multi *inm) > > /* XXX this access is not covered by IF_ADDR_LOCK */ > CTR2(KTR_IGMPV3, "%s: purging ifma %p", __func__, ifma); > - if (ifp) > - CURVNET_SET(ifp->if_vnet); > + if (ifp) { > + saved_vnet = curvnet; > + curvnet = ifp->if_vnet; > + } Uhmm... please don't do this, for at least two reasons: 1) so far we could identify all VNET context switches by tracking CURVNET_SET / _RESTORE macros. With this change a non-standard hack is introduced, opening the door for more alternative / creative variations to come, thus increasing the entropy 2) CURVNET_* macros provide elementary capability of tracking vnet recursions, and much more importantly, forgotten or missed context restores. Your change breaks this tracking chain. Is there a reason one could not extend struct in_multi with a struct vnet *inm_vnet entry, populate it on struct in_multi creation, and be done with all curvnet woes in a clean way? Marko > inm_purge(inm); > free(inm, M_IPMADDR); > > if_delmulti_ifma_flags(ifma, 1); > if (ifp) { > - CURVNET_RESTORE(); > + curvnet = saved_vnet; > if_rele(ifp); > } > } > @@ -1666,6 +1669,7 @@ inp_gcmoptions(epoch_context_t ctx) > struct in_mfilter *imf; > struct in_multi *inm; > struct ifnet *ifp; > + struct vnet *saved_vnet; > size_t idx, nmships; > > imo = __containerof(ctx, struct ip_moptions, imo_epoch_ctx); > @@ -1677,11 +1681,13 @@ inp_gcmoptions(epoch_context_t ctx) > imf_leave(imf); > inm = imo->imo_membership[idx]; > ifp = inm->inm_ifp; > - if (ifp) > - CURVNET_SET(ifp->if_vnet); > + if (ifp) { > + saved_vnet = curvnet; > + curvnet = ifp->if_vnet; > + } > (void)in_leavegroup(inm, imf); > if (ifp) > - CURVNET_RESTORE(); > + curvnet = saved_vnet; > if (imf) > imf_purge(imf); > } > > Modified: head/sys/netinet6/in6_mcast.c > ============================================================================== > --- head/sys/netinet6/in6_mcast.c Mon May 21 07:12:06 > 2018 (r333967) +++ head/sys/netinet6/in6_mcast.c Mon > May 21 08:34:10 2018 (r333968) @@ -524,6 +524,7 @@ > in6m_release(struct in6_multi *inm) { > struct ifmultiaddr *ifma; > struct ifnet *ifp; > + struct vnet *saved_vnet; > > CTR2(KTR_MLD, "%s: refcount is %d", __func__, > inm->in6m_refcount); > @@ -539,14 +540,16 @@ in6m_release(struct in6_multi *inm) > KASSERT(ifma->ifma_protospec == NULL, > ("%s: ifma_protospec != NULL", __func__)); > > - if (ifp) > - CURVNET_SET(ifp->if_vnet); > + if (ifp) { > + saved_vnet = curvnet; > + curvnet = ifp->if_vnet; > + } > in6m_purge(inm); > free(inm, M_IP6MADDR); > > if_delmulti_ifma_flags(ifma, 1); > if (ifp) { > - CURVNET_RESTORE(); > + curvnet = saved_vnet; > if_rele(ifp); > } > } > @@ -1628,6 +1631,7 @@ inp_gcmoptions(epoch_context_t ctx) > struct in6_mfilter *imf; > struct in6_multi *inm; > struct ifnet *ifp; > + struct vnet *saved_vnet; > size_t idx, nmships; > > imo = __containerof(ctx, struct ip6_moptions, > imo6_epoch_ctx); @@ -1639,11 +1643,13 @@ > inp_gcmoptions(epoch_context_t ctx) im6f_leave(imf); > inm = imo->im6o_membership[idx]; > ifp = inm->in6m_ifp; > - if (ifp) > - CURVNET_SET(ifp->if_vnet); > + if (ifp) { > + saved_vnet = curvnet; > + curvnet = ifp->if_vnet; > + } > (void)in6_leavegroup(inm, imf); > if (ifp) > - CURVNET_RESTORE(); > + curvnet = saved_vnet; > if (imf) > im6f_purge(imf); > } > _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
