panic: _bus_virt_to_bus for vioif on GCE with GENERIC kernel

[Paul Ripke <stix%stix.id.au@localhost>]

Just tried running a newly built kernel on a GCE instance, and ran into
this panic. The previously running kernel is 9.99.73 from back around
October last year.

Anyone else tried booting -current on GCE recently? My suspicion is
the VirtIO changes committed around Jan 20. I'll sync back prior to
those and retry, if nobody else beats me to it.

[   1.0303647] piixpm0: SMBus disabled
[   1.0303647] virtio0 at pci0 dev 3 function 0
[   1.0303647] virtio0: SCSI device (rev. 0x00)
[   1.0303647] vioscsi0 at virtio0: features: 0
[   1.0303647] vioscsi0: cmd_per_lun 8 qsize 8192 seg_max 64 max_target 253 max_lun 1
[   1.0303647] virtio0: config interrupting at msix0 vec 0
[   1.0303647] virtio0: queues interrupting at msix0 vec 1
[   1.0303647] scsibus0 at vioscsi0: 16 targets, 1 lun per target
[   1.0303647] virtio1 at pci0 dev 4 function 0
[   1.0303647] virtio1: network device (rev. 0x00)
[   1.0303647] vioif0 at virtio1: features: 0x20030020<EVENT_IDX,CTRL_VQ,STATUS,MAC>
[   1.0303647] vioif0: Ethernet address 42:01:0a:98:00:02
[   1.0303647] panic: _bus_virt_to_bus
[   1.0303647] cpu0: Begin traceback...
[   1.0303647] vpanic() at netbsd:vpanic+0x156
[   1.0303647] snprintf() at netbsd:snprintf
[   1.0303647] _bus_dma_alloc_bouncebuf() at netbsd:_bus_dma_alloc_bouncebuf
[   1.0303647] bus_dmamap_load() at netbsd:bus_dmamap_load+0x9c
[   1.0303647] vioif_dmamap_create_load.constprop.0() at netbsd:vioif_dmamap_create_load.constprop.0+0x7e
[   1.0303647] vioif_attach() at netbsd:vioif_attach+0x1088
[   1.0303647] config_attach_loc() at netbsd:config_attach_loc+0x17e
[   1.0303647] virtio_pci_rescan() at netbsd:virtio_pci_rescan+0x48
[   1.0303647] virtio_pci_attach() at netbsd:virtio_pci_attach+0x23a
[   1.0303647] config_attach_loc() at netbsd:config_attach_loc+0x17e
[   1.0303647] pci_probe_device() at netbsd:pci_probe_device+0x585
[   1.0303647] pci_enumerate_bus() at netbsd:pci_enumerate_bus+0x1b5
[   1.0303647] pcirescan() at netbsd:pcirescan+0x4e
[   1.0303647] pciattach() at netbsd:pciattach+0x186
[   1.0303647] config_attach_loc() at netbsd:config_attach_loc+0x17e
[   1.0303647] mp_pci_scan() at netbsd:mp_pci_scan+0x9e
[   1.0303647] amd64_mainbus_attach() at netbsd:amd64_mainbus_attach+0x236
[   1.0303647] mainbus_attach() at netbsd:mainbus_attach+0x84
[   1.0303647] config_attach_loc() at netbsd:config_attach_loc+0x17e
[   1.0303647] cpu_configure() at netbsd:cpu_configure+0x38
[   1.0303647] main() at netbsd:main+0x32c
[   1.0303647] cpu0: End traceback...
[   1.0303647] fatal breakpoint trap in supervisor mode
[   1.0303647] trap type 1 code 0 rip 0xffffffff80221a35 cs 0x8 rflags 0x202 cr2 0 ilevel 0x8 rsp 0xffffffff81cfa5d0
[   1.0303647] curlwp 0xffffffff81886e40 pid 0.0 lowest kstack 0xffffffff81cf52c0
Stopped in pid 0.0 (system) at  netbsd:breakpoint+0x5:  leave

-- 
Paul Ripke
"Great minds discuss ideas, average minds discuss events, small minds
 discuss people."
-- Disputed: Often attributed to Eleanor Roosevelt. 1948.