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* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2019-06-271-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | The new route handling in ip_mc_finish_output() from 'net' overlapped with the new support for returning congestion notifications from BPF programs. In order to handle this I had to take the dev_loopback_xmit() calls out of the switch statement. The aquantia driver conflicts were simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
| * ipv6: constify rt6_nexthop()Nicolas Dichtel2019-06-261-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | There is no functional change in this patch, it only prepares the next one. rt6_nexthop() will be used by ip6_dst_lookup_neigh(), which uses const variables. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Reported-by: kbuild test robot <lkp@intel.com> Acked-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | ipv6: Dump route exceptions if requestedStefano Brivio2019-06-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit 2b760fcf5cfb ("ipv6: hook up exception table to store dst cache"), route exceptions reside in a separate hash table, and won't be found by walking the FIB, so they won't be dumped to userspace on a RTM_GETROUTE message. This causes 'ip -6 route list cache' and 'ip -6 route flush cache' to have no function anymore: # ip -6 route get fc00:3::1 fc00:3::1 via fc00:1::2 dev veth_A-R1 src fc00:1::1 metric 1024 expires 539sec mtu 1400 pref medium # ip -6 route get fc00:4::1 fc00:4::1 via fc00:2::2 dev veth_A-R2 src fc00:2::1 metric 1024 expires 536sec mtu 1500 pref medium # ip -6 route list cache # ip -6 route flush cache # ip -6 route get fc00:3::1 fc00:3::1 via fc00:1::2 dev veth_A-R1 src fc00:1::1 metric 1024 expires 520sec mtu 1400 pref medium # ip -6 route get fc00:4::1 fc00:4::1 via fc00:2::2 dev veth_A-R2 src fc00:2::1 metric 1024 expires 519sec mtu 1500 pref medium because iproute2 lists cached routes using RTM_GETROUTE, and flushes them by listing all the routes, and deleting them with RTM_DELROUTE one by one. If cached routes are requested using the RTM_F_CLONED flag together with strict checking, or if no strict checking is requested (and hence we can't consistently apply filters), look up exceptions in the hash table associated with the current fib6_info in rt6_dump_route(), and, if present and not expired, add them to the dump. We might be unable to dump all the entries for a given node in a single message, so keep track of how many entries were handled for the current node in fib6_walker, and skip that amount in case we start from the same partially dumped node. When a partial dump restarts, as the starting node might change when 'sernum' changes, we have no guarantee that we need to skip the same amount of in-node entries. Therefore, we need two counters, and we need to zero the in-node counter if the node from which the dump is resumed differs. Note that, with the current version of iproute2, this only fixes the 'ip -6 route list cache': on a flush command, iproute2 doesn't pass RTM_F_CLONED and, due to this inconsistency, 'ip -6 route flush cache' is still unable to fetch the routes to be flushed. This will be addressed in a patch for iproute2. To flush cached routes, a procfs entry could be introduced instead: that's how it works for IPv4. We already have a rt6_flush_exception() function ready to be wired to it. However, this would not solve the issue for listing. Versions of iproute2 and kernel tested: iproute2 kernel 4.14.0 4.15.0 4.19.0 5.0.0 5.1.0 5.1.0, patched 3.18 list + + + + + + flush + + + + + + 4.4 list + + + + + + flush + + + + + + 4.9 list + + + + + + flush + + + + + + 4.14 list + + + + + + flush + + + + + + 4.15 list flush 4.19 list flush 5.0 list flush 5.1 list flush with list + + + + + + fix flush + + + + v7: - Explain usage of "skip" counters in commit message (suggested by David Ahern) v6: - Rebase onto net-next, use recently introduced nexthop walker - Make rt6_nh_dump_exceptions() a separate function (suggested by David Ahern) v5: - Use dump_routes and dump_exceptions from filter, ignore NLM_F_MATCH, update test results (flushing works with iproute2 < 5.0.0 now) v4: - Split NLM_F_MATCH and strict check handling in separate patches - Filter routes using RTM_F_CLONED: if it's not set, only return non-cached routes, and if it's set, only return cached routes: change requested by David Ahern and Martin Lau. This implies that iproute2 needs a separate patch to be able to flush IPv6 cached routes. This is not ideal because we can't fix the breakage caused by 2b760fcf5cfb entirely in kernel. However, two years have passed since then, and this makes it more tolerable v3: - More descriptive comment about expired exceptions in rt6_dump_route() - Swap return values of rt6_dump_route() (suggested by Martin Lau) - Don't zero skip_in_node in case we don't dump anything in a given pass (also suggested by Martin Lau) - Remove check on RTM_F_CLONED altogether: in the current UAPI semantic, it's just a flag to indicate the route was cloned, not to filter on routes v2: Add tracking of number of entries to be skipped in current node after a partial dump. As we restart from the same node, if not all the exceptions for a given node fit in a single message, the dump will not terminate, as suggested by Martin Lau. This is a concrete possibility, setting up a big number of exceptions for the same route actually causes the issue, suggested by David Ahern. Reported-by: Jianlin Shi <jishi@redhat.com> Fixes: 2b760fcf5cfb ("ipv6: hook up exception table to store dst cache") Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | ipv6: convert major tx path to use RT6_LOOKUP_F_DST_NOREFWei Wang2019-06-231-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For tx path, in most cases, we still have to take refcnt on the dst cause the caller is caching the dst somewhere. But it still is beneficial to make use of RT6_LOOKUP_F_DST_NOREF flag while doing the route lookup. It is cause this flag prevents manipulating refcnt on net->ipv6.ip6_null_entry when doing fib6_rule_lookup() to traverse each routing table. The null_entry is a shared object and constant updates on it cause false sharing. We converted the current major lookup function ip6_route_output_flags() to make use of RT6_LOOKUP_F_DST_NOREF. Together with the change in the rx path, we see noticable performance boost: I ran synflood tests between 2 hosts under the same switch. Both hosts have 20G mlx NIC, and 8 tx/rx queues. Sender sends pure SYN flood with random src IPs and ports using trafgen. Receiver has a simple TCP listener on the target port. Both hosts have multiple custom rules: - For incoming packets, only local table is traversed. - For outgoing packets, 3 tables are traversed to find the route. The packet processing rate on the receiver is as follows: - Before the fix: 3.78Mpps - After the fix: 5.50Mpps Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | ipv6: honor RT6_LOOKUP_F_DST_NOREF in rule lookup logicWei Wang2019-06-231-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | This patch specifically converts the rule lookup logic to honor this flag and not release refcnt when traversing each rule and calling lookup() on each routing table. Similar to previous patch, we also need some special handling of dst entries in uncached list because there is always 1 refcnt taken for them even if RT6_LOOKUP_F_DST_NOREF flag is set. Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | ipv6: introduce RT6_LOOKUP_F_DST_NOREF flag in ip6_pol_route()Wei Wang2019-06-231-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This new flag is to instruct the route lookup function to not take refcnt on the dst entry. The user which does route lookup with this flag must properly use rcu protection. ip6_pol_route() is the major route lookup function for both tx and rx path. In this function: Do not take refcnt on dst if RT6_LOOKUP_F_DST_NOREF flag is set, and directly return the route entry. The caller should be holding rcu lock when using this flag, and decide whether to take refcnt or not. One note on the dst cache in the uncached_list: As uncached_list does not consume refcnt, one refcnt is always returned back to the caller even if RT6_LOOKUP_F_DST_NOREF flag is set. Uncached dst is only possible in the output path. So in such call path, caller MUST check if the dst is in the uncached_list before assuming that there is no refcnt taken on the returned dst. Signed-off-by: Wei Wang <weiwan@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Acked-by: Mahesh Bandewar <maheshb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | ipv6: Plumb support for nexthop object in a fib6_infoDavid Ahern2019-06-041-2/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add struct nexthop and nh_list list_head to fib6_info. nh_list is the fib6_info side of the nexthop <-> fib_info relationship. Since a fib6_info referencing a nexthop object can not have 'sibling' entries (the old way of doing multipath routes), the nh_list is a union with fib6_siblings. Add f6i_list list_head to 'struct nexthop' to track fib6_info entries using a nexthop instance. Update __remove_nexthop_fib to walk f6_list and delete fib entries using the nexthop. Add a few nexthop helpers for use when a nexthop is added to fib6_info: - nexthop_fib6_nh - return first fib6_nh in a nexthop object - fib6_info_nh_dev moved to nexthop.h and updated to use nexthop_fib6_nh if the fib6_info references a nexthop object - nexthop_path_fib6_result - similar to ipv4, select a path within a multipath nexthop object. If the nexthop is a blackhole, set fib6_result type to RTN_BLACKHOLE, and set the REJECT flag Update the fib6_info references to check for nh and take a different path as needed: - rt6_qualify_for_ecmp - if a fib entry uses a nexthop object it can NOT be coalesced with other fib entries into a multipath route - rt6_duplicate_nexthop - use nexthop_cmp if either fib6_info references a nexthop - addrconf (host routes), RA's and info entries (anything configured via ndisc) does not use nexthop objects - fib6_info_destroy_rcu - put reference to nexthop object - fib6_purge_rt - drop fib6_info from f6i_list - fib6_select_path - update to use the new nexthop_path_fib6_result when fib entry uses a nexthop object - rt6_device_match - update to catch use of nexthop object as a blackhole and set fib6_type and flags. - ip6_route_info_create - don't add space for fib6_nh if fib entry is going to reference a nexthop object, take a reference to nexthop object, disallow use of source routing - rt6_nlmsg_size - add space for RTA_NH_ID - add rt6_fill_node_nexthop to add nexthop data on a dump As with ipv4, most of the changes push existing code into the else branch of whether the fib entry uses a nexthop object. Update the nexthop code to walk f6i_list on a nexthop deleted to remove fib entries referencing it. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | ipv6: Make fib6_nh optional at the end of fib6_infoDavid Ahern2019-05-241-2/+2
|/ | | | | | | | | | | | Move fib6_nh to the end of fib6_info and make it an array of size 0. Pass a flag to fib6_info_alloc indicating if the allocation needs to add space for a fib6_nh. The current code path always has a fib6_nh allocated with a fib6_info; with nexthop objects they will be separate. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Change nhc_flags to unsigned charDavid Ahern2019-04-231-1/+1
| | | | | | | | | | | | | | | | | nhc_flags holds the RTNH_F flags for a given nexthop (fib{6}_nh). All of the RTNH_F_ flags fit in an unsigned char, and since the API to userspace (rtnh_flags and lower byte of rtm_flags) is 1 byte it can not grow. Make nhc_flags in fib_nh_common an unsigned char and shrink the size of the struct by 8, from 56 to 48 bytes. Update the flags arguments for up netdevice events and fib_nexthop_info which determines the RTNH_F flags to return on a dump/event. The RTNH_F flags are passed in the lower byte of rtm_flags which is an unsigned int so use a temp variable for the flags to fib_nexthop_info and combine with rtm_flags in the caller. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv6: Restore RTF_ADDRCONF check in rt6_qualify_for_ecmpDavid Ahern2019-04-211-1/+3
| | | | | | | | | | The RTF_ADDRCONF flag filters out routes added by RA's in determining which routes can be appended to an existing one to create a multipath route. Restore the flag check and add a comment to document the RA piece. Fixes: 4e54507ab1a9 ("ipv6: Simplify rt6_qualify_for_ecmp") Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv6: Simplify rt6_qualify_for_ecmpDavid Ahern2019-04-211-2/+1
| | | | | | | | | | | | | | | | | After commit c7a1ce397ada ("ipv6: Change addrconf_f6i_alloc to use ip6_route_info_create"), the gateway is no longer filled in for fib6_nh structs in a prefix route. Accordingly, the RTF_ADDRCONF flag check can be dropped from the 'rt6_qualify_for_ecmp'. Further, RTF_DYNAMIC is only set in rt6_info instances, so it can be removed from the check as well. This reduces rt6_qualify_for_ecmp and the mlxsw version to just checking if the nexthop has a gateway which is the real indication of whether entries can be coalesced into a multipath route. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv6: Pass fib6_result to ip6_mtu_from_fib6 and fib6_mtuDavid Ahern2019-04-171-2/+3
| | | | | | | | | | | Change ip6_mtu_from_fib6 and fib6_mtu to take a fib6_result over a fib6_info. Update both to use the fib6_nh from fib6_result. Since the signature of ip6_mtu_from_fib6 is already changing, add const to daddr and saddr. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Replace nhc_has_gw with nhc_gw_familyDavid Ahern2019-04-081-1/+1
| | | | | | | | | | | | | Allow the gateway in a fib_nh_common to be from a different address family than the outer fib{6}_nh. To that end, replace nhc_has_gw with nhc_gw_family and update users of nhc_has_gw to check nhc_gw_family. Now nhc_family is used to know if the nh_common is part of a fib_nh or fib6_nh (used for container_of to get to route family specific data), and nhc_gw_family represents the address family for the gateway. Signed-off-by: David Ahern <dsahern@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv6: Rename fib6_nh entriesDavid Ahern2019-03-291-3/+5
| | | | | | | | | | | | Rename fib6_nh entries that will be moved to a fib_nh_common struct. Specifically, the device, gateway, flags, and lwtstate are common with all nexthop definitions. In some places new temporary variables are declared or local variables renamed to maintain line lengths. Rename only; no functional change intended. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv6: Move gateway checks to a fib6_nh settingDavid Ahern2019-03-291-2/+2
| | | | | | | | | | | | | | | The gateway setting is not per fib6_info entry but per-fib6_nh. Add a new fib_nh_has_gw flag to fib6_nh and convert references to RTF_GATEWAY to the new flag. For IPv6 address the flag is cheaper than checking that nh_gw is non-0 like IPv4 does. While this increases fib6_nh by 8-bytes, the effective allocation size of a fib6_info is unchanged. The 8 bytes is recovered later with a fib_nh_common change. Signed-off-by: David Ahern <dsahern@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Add struct for fib dump filterDavid Ahern2018-10-161-0/+1
| | | | | | | | | | | | | Add struct fib_dump_filter for options on limiting which routes are returned in a dump request. The current list is table id, protocol, route type, rtm_flags and nexthop device index. struct net is needed to lookup the net_device from the index. Declare the filter for each route dump handler and plumb the new arguments from dump handlers to ip_valid_fib_dump_req. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: remove 1 always zero parameter from ip6_redirect_no_header()Maciej Żenczykowski2018-10-021-2/+1
| | | | | | | | (the parameter in question is mark) Signed-off-by: Maciej Żenczykowski <maze@google.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net/ipv6: Revert attempt to simplify route replace and appendDavid Ahern2018-07-041-0/+6
| | | | | | | | | | | | | | | | NetworkManager likes to manage linklocal prefix routes and does so with the NLM_F_APPEND flag, breaking attempts to simplify the IPv6 route code and by extension enable multipath routes with device only nexthops. Revert f34436a43092 and these followup patches: 6eba08c3626b ("ipv6: Only emit append events for appended routes"). ce45bded6435 ("mlxsw: spectrum_router: Align with new route replace logic") 53b562df8c20 ("mlxsw: spectrum_router: Allow appending to dev-only routes") Update the fib_tests cases to reflect the old behavior. Fixes: f34436a43092 ("net/ipv6: Simplify route replace and appending into multipath route") Signed-off-by: David Ahern <dsahern@gmail.com>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller2018-05-241-0/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Alexei Starovoitov says: ==================== pull-request: bpf-next 2018-05-24 The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) Björn Töpel cleans up AF_XDP (removes rebind, explicit cache alignment from uapi, etc). 2) David Ahern adds mtu checks to bpf_ipv{4,6}_fib_lookup() helpers. 3) Jesper Dangaard Brouer adds bulking support to ndo_xdp_xmit. 4) Jiong Wang adds support for indirect and arithmetic shifts to NFP 5) Martin KaFai Lau cleans up BTF uapi and makes the btf_header extensible. 6) Mathieu Xhonneux adds an End.BPF action to seg6local with BPF helpers allowing to edit/grow/shrink a SRH and apply on a packet generic SRv6 actions. 7) Sandipan Das adds support for bpf2bpf function calls in ppc64 JIT. 8) Yonghong Song adds BPF_TASK_FD_QUERY command for introspection of tracing events. 9) other misc fixes from Gustavo A. R. Silva, Sirio Balmelli, John Fastabend, and Magnus Karlsson ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| * net/ipv6: Add helper to return path MTU based on fib resultDavid Ahern2018-05-221-0/+3
| | | | | | | | | | | | | | | | | | | | | | Determine path MTU from a FIB lookup result. Logic is based on ip6_dst_mtu_forward plus lookup of nexthop exception. Add ip6_dst_mtu_forward to ipv6_stubs to handle access by core bpf code. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
* | net/ipv6: Simplify route replace and appending into multipath routeDavid Ahern2018-05-221-6/+0
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Bring consistency to ipv6 route replace and append semantics. Remove rt6_qualify_for_ecmp which is just guess work. It fails in 2 cases: 1. can not replace a route with a reject route. Existing code appends a new route instead of replacing the existing one. 2. can not have a multipath route where a leg uses a dev only nexthop Existing use cases affected by this change: 1. adding a route with existing prefix and metric using NLM_F_CREATE without NLM_F_APPEND or NLM_F_EXCL (ie., what iproute2 calls 'prepend'). Existing code auto-determines that the new nexthop can be appended to an existing route to create a multipath route. This change breaks that by requiring the APPEND flag for the new route to be added to an existing one. Instead the prepend just adds another route entry. 2. route replace. Existing code replaces first matching multipath route if new route is multipath capable and fallback to first matching non-ECMP route (reject or dev only route) in case one isn't available. New behavior replaces first matching route. (Thanks to Ido for spotting this one) Note: Newer iproute2 is needed to display multipath routes with a dev-only nexthop. This is due to a bug in iproute2 and parsing nexthops. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-nextDavid S. Miller2018-05-061-0/+21
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pablo Neira Ayuso says: ==================== Netfilter/IPVS updates for net-next The following patchset contains Netfilter/IPVS updates for your net-next tree, more relevant updates in this batch are: 1) Add Maglev support to IPVS. Moreover, store lastest server weight in IPVS since this is needed by maglev, patches from from Inju Song. 2) Preparation works to add iptables flowtable support, patches from Felix Fietkau. 3) Hand over flows back to conntrack slow path in case of TCP RST/FIN packet is seen via new teardown state, also from Felix. 4) Add support for extended netlink error reporting for nf_tables. 5) Support for larger timeouts that 23 days in nf_tables, patch from Florian Westphal. 6) Always set an upper limit to dynamic sets, also from Florian. 7) Allow number generator to make map lookups, from Laura Garcia. 8) Use hash_32() instead of opencode hashing in IPVS, from Vicent Bernat. 9) Extend ip6tables SRH match to support previous, next and last SID, from Ahmed Abdelsalam. 10) Move Passive OS fingerprint nf_osf.c, from Fernando Fernandez. 11) Expose nf_conntrack_max through ctnetlink, from Florent Fourcot. 12) Several housekeeping patches for xt_NFLOG, x_tables and ebtables, from Taehee Yoo. 13) Unify meta bridge with core nft_meta, then make nft_meta built-in. Make rt and exthdr built-in too, again from Florian. 14) Missing initialization of tbl->entries in IPVS, from Cong Wang. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| * ipv6: make ip6_dst_mtu_forward inlineFelix Fietkau2018-04-211-0/+21
| | | | | | | | | | | | | | Just like ip_dst_mtu_maybe_forward(), to avoid a dependency with ipv6.ko. Signed-off-by: Felix Fietkau <nbd@nbd.name> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* | net/ipv6: Remove compare of fib6_idev from rt6_duplicate_nexthopDavid Ahern2018-04-191-1/+0
| | | | | | | | | | | | | | | | | | | | After 4832c30d5458 ("net: ipv6: put host and anycast routes on device with address") the comparison of idev does not add value since it correlates to the nexthop device which is already compared. Remove the idev comparison. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net/ipv6: Change ip6_route_get_saddr to get dev from routeDavid Ahern2018-04-191-5/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Prior to 4832c30d5458 ("net: ipv6: put host and anycast routes on device with address") host routes and anycast routes were installed with the device set to loopback (or VRF device once that feature was added). In the older code dst.dev was set to loopback (needed for packet tx) and rt6i_idev was used to denote the actual interface. Commit 4832c30d5458 changed the code to have dst.dev pointing to the real device with the switch to lo or vrf device done on dst clones. As a consequence of this change ip6_route_get_saddr can just pass the nexthop device to ipv6_dev_get_saddr. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net/ipv6: Rename addrconf_dst_allocDavid Ahern2018-04-191-1/+1
| | | | | | | | | | | | | | | | | | | | addrconf_dst_alloc now returns a fib6_info. Update the name and its users to reflect the change. Rename only; no functional change intended. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net/ipv6: Rename fib6_info struct elementsDavid Ahern2018-04-191-13/+13
|/ | | | | | | | | | | Change the prefix for fib6_info struct elements from rt6i_ to fib6_. rt6i_pcpu and rt6i_exception_bucket are left as is given that they point to rt6_info entries. Rename only; not functional change intended. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net/ipv6: Flip FIB entries to fib6_infoDavid Ahern2018-04-171-14/+14
| | | | | | | | Convert all code paths referencing a FIB entry from rt6_info to fib6_info. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net/ipv6: separate handling of FIB entries from dst based routesDavid Ahern2018-04-171-2/+1
| | | | | | | | | | | | | | | | | Last step before flipping the data type for FIB entries: - use fib6_info_alloc to create FIB entries in ip6_route_info_create and addrconf_dst_alloc - use fib6_info_release in place of dst_release, ip6_rt_put and rt6_release - remove the dst_hold before calling __ip6_ins_rt or ip6_del_rt - when purging routes, drop per-cpu routes - replace inc and dec of rt6i_ref with fib6_info_hold and fib6_info_release - use rt->from since it points to the FIB entry - drop references to exception bucket, fib6_metrics and per-cpu from dst entries (those are relevant for fib entries only) Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net/ipv6: Cleanup exception and cache route handlingDavid Ahern2018-04-171-1/+0
| | | | | | | | | | | | | | | | | | | | IPv6 FIB will only contain FIB entries with exception routes added to the FIB entry. Once this transformation is complete, FIB lookups will return a fib6_info with the lookup functions still returning a dst based rt6_info. The current code uses rt6_info for both paths and overloads the rt6_info variable usually called 'rt'. This patch introduces a new 'f6i' variable name for the result of the FIB lookup and keeps 'rt' as the dst based return variable. 'f6i' becomes a fib6_info in a later patch which is why it is introduced as f6i now; avoids the additional churn in the later patch. In addition, remove RTF_CACHE and dst checks from fib6 add and delete since they can not happen now and will never happen after the data type flip. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net/ipv6: Add gfp_flags to route add functionsDavid Ahern2018-04-171-2/+4
| | | | | | | | | | | Most FIB entries can be added using memory allocated with GFP_KERNEL. Add gfp_flags to ip6_route_add and addrconf_dst_alloc. Code paths that can be reached from the packet path (e.g., ndisc and autoconfig) or atomic notifiers use GFP_ATOMIC; paths from user context (adding addresses and routes) use GFP_KERNEL. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net/ipv6: Create a neigh_lookup for FIB entriesDavid Ahern2018-04-171-0/+3
| | | | | | | | | | | The router discovery code has a FIB entry and wants to validate the gateway has a neighbor entry. Refactor the existing dst_neigh_lookup for IPv6 and create a new function that takes the gateway and device and returns a neighbor entry. Use the new function in ndisc_router_discovery to validate the gateway. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net/ipv6: Move nexthop data to fib6_nhDavid Ahern2018-04-171-3/+3
| | | | | | | | | | Introduce fib6_nh structure and move nexthop related data from rt6_info and rt6_info.dst to fib6_nh. References to dev, gateway or lwtstate from a FIB lookup perspective are converted to use fib6_nh; datapath references to dst version are left as is. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net/ipv6: Pass net namespace to route functionsDavid Ahern2018-04-171-5/+7
| | | | | | | | Pass network namespace reference into route add, delete and get functions. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv6: add a wrapper for ip6_dst_store() with flowi6 checksAlexey Kodanev2018-04-041-0/+3
| | | | | | | | | | | | Move commonly used pattern of ip6_dst_store() usage to a separate function - ip6_sk_dst_store_flow(), which will check the addresses for equality using the flow information, before saving them. There is no functional changes in this patch. In addition, it will be used in the next patch, in ip6_sk_dst_lookup_flow(). Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2018-03-231-0/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fun set of conflict resolutions here... For the mac80211 stuff, these were fortunately just parallel adds. Trivially resolved. In drivers/net/phy/phy.c we had a bug fix in 'net' that moved the function phy_disable_interrupts() earlier in the file, whilst in 'net-next' the phy_error() call from this function was removed. In net/ipv4/xfrm4_policy.c, David Ahern's changes to remove the 'rt_table_id' member of rtable collided with a bug fix in 'net' that added a new struct member "rt_mtu_locked" which needs to be copied over here. The mlxsw driver conflict consisted of net-next separating the span code and definitions into separate files, whilst a 'net' bug fix made some changes to that moved code. The mlx5 infiniband conflict resolution was quite non-trivial, the RDMA tree's merge commit was used as a guide here, and here are their notes: ==================== Due to bug fixes found by the syzkaller bot and taken into the for-rc branch after development for the 4.17 merge window had already started being taken into the for-next branch, there were fairly non-trivial merge issues that would need to be resolved between the for-rc branch and the for-next branch. This merge resolves those conflicts and provides a unified base upon which ongoing development for 4.17 can be based. Conflicts: drivers/infiniband/hw/mlx5/main.c - Commit 42cea83f9524 (IB/mlx5: Fix cleanup order on unload) added to for-rc and commit b5ca15ad7e61 (IB/mlx5: Add proper representors support) add as part of the devel cycle both needed to modify the init/de-init functions used by mlx5. To support the new representors, the new functions added by the cleanup patch needed to be made non-static, and the init/de-init list added by the representors patch needed to be modified to match the init/de-init list changes made by the cleanup patch. Updates: drivers/infiniband/hw/mlx5/mlx5_ib.h - Update function prototypes added by representors patch to reflect new function names as changed by cleanup patch drivers/infiniband/hw/mlx5/ib_rep.c - Update init/de-init stage list to match new order from cleanup patch ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| * xfrm: reuse uncached_list to track xdstsXin Long2018-02-161-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In early time, when freeing a xdst, it would be inserted into dst_garbage.list first. Then if it's refcnt was still held somewhere, later it would be put into dst_busy_list in dst_gc_task(). When one dev was being unregistered, the dev of these dsts in dst_busy_list would be set with loopback_dev and put this dev. So that this dev's removal wouldn't get blocked, and avoid the kmsg warning: kernel:unregister_netdevice: waiting for veth0 to become \ free. Usage count = 2 However after Commit 52df157f17e5 ("xfrm: take refcnt of dst when creating struct xfrm_dst bundle"), the xdst will not be freed with dst gc, and this warning happens. To fix it, we need to find these xdsts that are still held by others when removing the dev, and free xdst's dev and set it with loopback_dev. But unfortunately after flow_cache for xfrm was deleted, no list tracks them anymore. So we need to save these xdsts somewhere to release the xdst's dev later. To make this easier, this patch is to reuse uncached_list to track xdsts, so that the dev refcnt can be released in the event NETDEV_UNREGISTER process of fib_netdev_notifier. Thanks to Florian, we could move forward this fix quickly. Fixes: 52df157f17e5 ("xfrm: take refcnt of dst when creating struct xfrm_dst bundle") Reported-by: Jianlin Shi <jishi@redhat.com> Reported-by: Hangbin Liu <liuhangbin@gmail.com> Tested-by: Eyal Birger <eyal.birger@gmail.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
* | net/ipv6: Add support for path selection using hash of 5-tupleDavid Ahern2018-03-041-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some operators prefer IPv6 path selection to use a standard 5-tuple hash rather than just an L3 hash with the flow the label. To that end add support to IPv6 for multipath hash policy similar to bf4e0a3db97eb ("net: ipv4: add support for ECMP hash policy choice"). The default is still L3 which covers source and destination addresses along with flow label and IPv6 protocol. Signed-off-by: David Ahern <dsahern@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Tested-by: Ido Schimmel <idosch@mellanox.com> Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net/ipv6: Pass skb to route lookupDavid Ahern2018-03-041-4/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | IPv6 does path selection for multipath routes deep in the lookup functions. The next patch adds L4 hash option and needs the skb for the forward path. To get the skb to the relevant FIB lookup functions it needs to go through the fib rules layer, so add a lookup_data argument to the fib_lookup_arg struct. Signed-off-by: David Ahern <dsahern@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | ipv6: route: dissect flow in input path if fib rules need itRoopa Prabhu2018-02-281-1/+3
|/ | | | | | | | | | | | | | | Dissect flow in fwd path if fib rules require it. Controlled by a flag to avoid penatly for the common case. Flag is set when fib rules with sport, dport and proto match that require flow dissect are installed. Also passes the dissected hash keys to the multipath hash function when applicable to avoid dissecting the flow again. icmp packets will continue to use inner header for hash calculations. Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv6: Calculate hash thresholds for IPv6 nexthopsIdo Schimmel2018-01-101-0/+7
| | | | | | | | | | | | | | | | | Before we convert IPv6 to use hash-threshold instead of modulo-N, we first need each nexthop to store its region boundary in the hash function's output space. The boundary is calculated by dividing the output space equally between the different active nexthops. That is, nexthops that are not dead or linkdown. The boundaries are rebalanced whenever a nexthop is added or removed to a multipath route and whenever a nexthop becomes active or inactive. Signed-off-by: Ido Schimmel <idosch@mellanox.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv6: Set nexthop flags upon carrier changeIdo Schimmel2018-01-071-0/+1
| | | | | | | | | | | | | | | | | | | | Similar to IPv4, when the carrier of a netdev changes we should toggle the 'linkdown' flag on all the nexthops using it as their nexthop device. This will later allow us to test for the presence of this flag during route lookup and dump. Up until commit 4832c30d5458 ("net: ipv6: put host and anycast routes on device with address") host and anycast routes used the loopback netdev as their nexthop device and thus were not marked with the 'linkdown' flag. The patch preserves this behavior and allows one to ping the local address even when the nexthop device does not have a carrier and the 'ignore_routes_with_linkdown' sysctl is set. Signed-off-by: Ido Schimmel <idosch@mellanox.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv6: Prepare to handle multiple netdev eventsIdo Schimmel2018-01-071-1/+1
| | | | | | | | | | | | | | | | | | To make IPv6 more in line with IPv4 we need to be able to respond differently to different netdev events. For example, when a netdev is unregistered all the routes using it as their nexthop device should be flushed, whereas when the netdev's carrier changes only the 'linkdown' flag should be toggled. Currently, this is not possible, as the function that traverses the routing tables is not aware of the triggering event. Propagate the triggering event down, so that it could be used in later patches. Signed-off-by: Ido Schimmel <idosch@mellanox.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv6: Clear nexthop flags upon netdev upIdo Schimmel2018-01-071-0/+1
| | | | | | | | | Previous patch marked nexthops with the 'dead' and 'linkdown' flags. Clear these flags when the netdev comes back up. Signed-off-by: Ido Schimmel <idosch@mellanox.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2017-11-041-0/+1
|\ | | | | | | | | | | | | Files removed in 'net-next' had their license header updated in 'net'. We take the remove from 'net-next'. Signed-off-by: David S. Miller <davem@davemloft.net>
| * License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman2017-11-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | ipv6: prepare fib6_age() for exception tableWei Wang2017-10-071-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If all dst cache entries are stored in the exception table under the main route, we have to go through them during fib6_age() when doing garbage collecting. Introduce a new function rt6_age_exception() which goes through all dst entries in the exception table and remove those entries that are expired. This function is called in fib6_age() so that all dst caches are also garbage collected. Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | ipv6: introduce a hash table to store dst cacheWei Wang2017-10-071-0/+3
|/ | | | | | | | | | | | | | | Add a hash table into struct rt6_info in order to store dst caches created by pmtu discovery and ip redirect in ipv6 routing code. APIs to add dst cache, delete dst cache, find dst cache and update dst cache in the hash table are implemented and will be used in later commits. This is a preparation work to move all cache routes into the exception table instead of getting inserted into the fib6 tree. Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv6: Use rt6i_idev index for echo replies to a local addressDavid Ahern2017-08-291-0/+10
| | | | | | | | | | | | | | | | | | Tariq repored local pings to linklocal address is failing: $ ifconfig ens8 ens8: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 11.141.16.6 netmask 255.255.0.0 broadcast 11.141.255.255 inet6 fe80::7efe:90ff:fecb:7502 prefixlen 64 scopeid 0x20<link> ether 7c:fe:90:cb:75:02 txqueuelen 1000 (Ethernet) RX packets 12 bytes 1164 (1.1 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 30 bytes 2484 (2.4 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 $ /bin/ping6 -c 3 fe80::7efe:90ff:fecb:7502%ens8 PING fe80::7efe:90ff:fecb:7502%ens8(fe80::7efe:90ff:fecb:7502) 56 data bytes Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv6: Compute multipath hash for ICMP errors from offending packetJakub Sitnicki2017-08-241-0/+1
| | | | | | | | | | | | | | | | | | | | | When forwarding or sending out an ICMPv6 error, look at the embedded packet that triggered the error and compute a flow hash over its headers. This let's us route the ICMP error together with the flow it belongs to when multipath (ECMP) routing is in use, which in turn makes Path MTU Discovery work in ECMP load-balanced or anycast setups (RFC 7690). Granted, end-hosts behind the ECMP router (aka servers) need to reflect the IPv6 Flow Label for PMTUD to work. The code is organized to be in parallel with ipv4 stack: ip_multipath_l3_keys -> ip6_multipath_l3_keys fib_multipath_hash -> rt6_multipath_hash Signed-off-by: Jakub Sitnicki <jkbs@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>