kern/51531: Recent networking regression affecting installs

[gson%gson.org@localhost (Andreas Gustafsson)]

>Number:         51531
>Category:       kern
>Synopsis:       Recent networking regression affecting installs
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed Oct 05 14:00:00 +0000 2016
>Originator:     Andreas Gustafsson
>Release:        NetBSD-current, source date >= 2016.09.16.23.01.53
>Organization:
>Environment:
System: NetBSD
Architecture: i386
Machine: i386
>Description:

I have an automated testing setup that netboots an INSTALL kernel and
performs a scripted installation of NetBSD/i386 or /amd64 on physical
hardware using sysinst.

This stopped working on both i386 and amd64 some time during the
period of build breakage lasting from 2016.09.16.11.35.07 to
2016.09.16.23.01.53, and is still broken as of 2016.10.05.03.46.38.

The ping test performed by sysinst fails with "100.0% packet loss, and
then the HTTP download of the first installation set fails:

  ftp: Can't connect to `10.169.0.1:80': Operation timed out

A log from the most recent installation attempt is here, but a bit
hard to read because it contains terminal escape sequences from
sysinst (with the ESC characters stripped):

  http://www.gson.org/netbsd/bugs/build/i386-baremetal/2016/2016.10.05.03.46.38/install.log

The problem started with one of the following commits:

   2016.09.16.11.35.07 jdolecek src/sys/dev/pci/nvme_pci.c 1.6
   2016.09.16.11.35.07 jdolecek src/sys/modules/Makefile 1.177
   2016.09.16.11.35.07 jdolecek src/sys/modules/nvme/Makefile 1.1
   2016.09.16.11.35.07 jdolecek src/sys/modules/nvme/nvme.ioconf 1.1
   2016.09.16.11.41.40 jdolecek src/sys/dev/ic/nvme.c 1.6
   2016.09.16.11.48.10 maxv src/sys/arch/amd64/amd64/trap.c 1.85
   2016.09.16.11.48.10 maxv src/sys/arch/i386/i386/trap.c 1.279
   2016.09.16.12.28.41 maxv src/sys/arch/i386/i386/copy.S 1.25
   2016.09.16.12.31.27 jdolecek src/share/man/man4/nvme.4 1.3
   2016.09.16.12.43.37 wiz src/share/man/man4/nvme.4 1.4
   2016.09.16.12.57.26 jdolecek src/sys/dev/ic/nvme.c 1.7
   2016.09.16.13.47.47 roy src/sys/netinet/if_arp.c 1.226
   2016.09.16.13.56.36 jdolecek src/share/man/man9/pci_msi.9 1.13
   2016.09.16.14.17.23 roy src/sys/net/if_spppsubr.c 1.152
   2016.09.16.14.17.23 roy src/sys/netinet/in.c 1.182
   2016.09.16.14.17.23 roy src/sys/netinet/in_var.h 1.83
   2016.09.16.14.55.28 jdolecek src/doc/roadmaps/storage 1.16
   2016.09.16.15.02.23 jdolecek src/doc/roadmaps/storage 1.17
   2016.09.16.15.20.50 jdolecek src/sys/dev/ata/ld_ataraid.c 1.42
   2016.09.16.15.20.50 jdolecek src/sys/dev/i2o/ld_iop.c 1.36
   2016.09.16.15.20.50 jdolecek src/sys/dev/ic/ld_aac.c 1.29
   2016.09.16.15.20.50 jdolecek src/sys/dev/ic/ld_cac.c 1.29
   2016.09.16.15.20.50 jdolecek src/sys/dev/ic/ld_icp.c 1.28
   2016.09.16.15.20.50 jdolecek src/sys/dev/ic/ld_mlx.c 1.22
   2016.09.16.15.20.50 jdolecek src/sys/dev/ic/ld_nvme.c 1.2
   2016.09.16.15.20.50 jdolecek src/sys/dev/ld.c 1.95
   2016.09.16.15.20.50 jdolecek src/sys/dev/ldvar.h 1.28
   2016.09.16.15.20.50 jdolecek src/sys/dev/pci/ld_amr.c 1.24
   2016.09.16.15.20.50 jdolecek src/sys/dev/pci/ld_twa.c 1.18
   2016.09.16.15.20.50 jdolecek src/sys/dev/pci/ld_twe.c 1.38
   2016.09.16.15.20.50 jdolecek src/sys/dev/pci/ld_virtio.c 1.11
   2016.09.16.15.20.50 jdolecek src/sys/dev/sdmmc/ld_sdmmc.c 1.22
   2016.09.16.15.24.47 jdolecek src/sys/dev/ic/ld_nvme.c 1.3
   2016.09.16.17.12.06 christos src/lib/libc/time/Makefile 1.33
   2016.09.16.17.12.06 christos src/lib/libc/time/NEWS 1.16
   2016.09.16.17.12.06 christos src/lib/libc/time/Theory 1.20
   2016.09.16.17.12.06 christos src/lib/libc/time/tz-art.htm 1.13
   2016.09.16.17.12.06 christos src/lib/libc/time/tz-how-to.html 1.1
   2016.09.16.17.12.06 christos src/lib/libc/time/tz-link.htm 1.26
   2016.09.16.17.12.06 christos src/lib/libc/time/zic.c 1.59
   2016.09.16.17.13.06 christos src/doc/3RDPARTY 1.1361
   2016.09.16.17.13.06 christos src/doc/CHANGES 1.2185
   2016.09.16.17.27.09 matt src/sys/uvm/pmap/pmap.c 1.22
   2016.09.16.17.32.36 scole src/sys/arch/macppc/dev/platinumfb.c 1.3
   2016.09.16.20.30.14 christos src/external/gpl3/gcc/dist/gcc/config/m68k/m68k.md 1.5
   2016.09.16.20.31.00 christos src/external/gpl3/gcc/dist/gcc/config/m68k/m68k.c 1.2
   2016.09.16.22.39.35 macallan src/sys/arch/sparc/dev/cgfourteen.c 1.82
   2016.09.16.23.01.53 pgoyette src/distrib/sets/lists/modules/mi 1.95

Those by roy are the only ones that look networking related to me.

>How-To-Repeat:

Attempt a network install of -current.

>Fix: