On Wed, May 02, 2018 at 09:43:50AM -0700, Eric Dumazet wrote: > > > On 01/09/2018 07:43 PM, David Ahern wrote: > > On 1/9/18 7:40 AM, Ido Schimmel wrote: > >> 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 <ido...@mellanox.com> > >> --- > >> include/net/ip6_fib.h | 1 + > >> include/net/ip6_route.h | 7 ++++ > >> net/ipv6/ip6_fib.c | 8 ++--- > >> net/ipv6/route.c | 96 > >> +++++++++++++++++++++++++++++++++++++++++++++++++ > >> 4 files changed, 106 insertions(+), 6 deletions(-) > >> > > > > LGTM. > > Acked-by: David Ahern <dsah...@gmail.com> > > > > For some reason I have a divide by zero error booting my hosts with latest > net tree. > > What guarantee do we have that total is not zero when rt6_upper_bound_set() > is called ?
Thanks for the report, Eric. I believe I didn't cover all the cases and 'rt6i_nh_weight' might be 0 is some cases. I'll try to reproduce and work on a fix. > > > > [ 8.498639] divide error: 0000 [#1] SMP PTI > [ 8.503178] gsmi: Log Shutdown Reason 0x03 > [ 8.507270] Modules linked in: bnx2x mdio > [ 8.511276] CPU: 17 PID: 116 Comm: kworker/17:0 Not tainted 4.17.0-smp-DEV > #110 > [ 8.518571] Hardware name: Intel RML,PCH/Ibis_QC_18, BIOS 2.40.0 06/22/2016 > [ 8.525526] Workqueue: ipv6_addrconf addrconf_dad_work > [ 8.530662] RIP: 0010:rt6_multipath_rebalance.part.82+0x1cb/0x1f0 > [ 8.536752] RSP: 0018:ffffba72867cbbf8 EFLAGS: 00010246 > [ 8.541966] RAX: 0000000000000000 RBX: 0000000000000025 RCX: > ffff9d555ab73180 > [ 8.549090] RDX: 0000000000000000 RSI: ffff9d4d5a34b1c0 RDI: > 0000000000000000 > [ 8.556212] RBP: ffffba72867cbc00 R08: 0000000000000000 R09: > 0000000000000000 > [ 8.563336] R10: 0000000000000000 R11: 0000000000000000 R12: > ffff9d5559f95680 > [ 8.570457] R13: ffff9d4d5a34b1c0 R14: ffff9d555ab73180 R15: > 0000000000000000 > [ 8.577579] FS: 0000000000000000(0000) GS:ffff9d4d5fc40000(0000) > knlGS:0000000000000000 > [ 8.585654] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 8.591391] CR2: 00007fffe47ff000 CR3: 0000000c39c0a001 CR4: > 00000000000606e0 > [ 8.598515] Call Trace: > [ 8.600961] ? rt6_multipath_rebalance+0x21/0x30 > [ 8.605579] fib6_add+0x75f/0xf70 > [ 8.608899] ? __wake_up+0x13/0x20 > [ 8.612303] ? netlink_broadcast_filtered+0x14c/0x3c0 > [ 8.617355] __ip6_ins_rt+0x4c/0x70 > [ 8.620847] ip6_ins_rt+0x6e/0xa0 > [ 8.624157] __ipv6_ifa_notify+0x226/0x2e0 > [ 8.628249] ipv6_ifa_notify+0x2a/0x40 > [ 8.631999] addrconf_dad_completed+0x59/0x360 > [ 8.636438] addrconf_dad_work+0x11c/0x400 > [ 8.640536] ? addrconf_dad_work+0x11c/0x400 > [ 8.644810] process_one_work+0x184/0x370 > [ 8.648820] ? process_one_work+0x184/0x370 > [ 8.652996] worker_thread+0x35/0x3a0 > [ 8.656654] kthread+0x121/0x140 > [ 8.659887] ? process_one_work+0x370/0x370 > [ 8.664073] ? kthread_create_worker_on_cpu+0x70/0x70 > [ 8.669118] ret_from_fork+0x35/0x40 > [ 8.672693] Code: c3 8b b9 38 01 00 00 eb aa 48 63 81 38 01 00 00 89 fa 41 > 89 f8 c1 ea 1f 01 fa d1 fa 48 63 d2 49 89 c2 48 c1 e0 1f 48 01 d0 31 d2 <49> > f7 f0 83 e8 01 48 39 ce 89 81 b4 00 00 00 0f 85 e2 fe ff ff > [ 8.691533] RIP: rt6_multipath_rebalance.part.82+0x1cb/0x1f0 RSP: > ffffba72867cbbf8 > [ 8.699135] ---[ end trace 9ae26819121cdc3a ]--- > [ 8.703760] Kernel panic - not syncing: Fatal exception in interrupt > [ 8.710169] Kernel Offset: 0x3d200000 from 0xffffffff81000000 (relocation > range: 0xffffffff80000000-0xffffffffbfffffff) > [ 8.721256] gsmi: Log Shutdown Reason 0x02 > [ 8.725357] Rebooting in 10 seconds.. > > >
