kern/52383: NetBSD 7 crashes with and urndis(4) devices since newer USB stack

[Pierre Pronchery <khorben%defora.org@localhost>]

>Number:         52383
>Category:       kern
>Synopsis:       Crash when connecting specific USB devices
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Jul 09 14:15:00 +0000 2017
>Originator:     Pierre Pronchery <khorben%defora.org@localhost>
>Release:        NetBSD 7.1_STABLE
>Organization:
>Environment:
System: NetBSD Amnesiac 7.1_STABLE NetBSD 7.1_STABLE (GENERIC) amd64
Architecture: x86_64
Machine: amd64
>Description:
Connecting my Jolla Jolla (1st generation) phone after boot-time results
in the following crash: (transcribed manually)

urndis0: usb errors on rx: IOERROR
urndis0: at uhub1 port 3 (addr 3) disconnected
uvm_fault(0xffffffff8106f240, 0x0, 1) -> e
fatal page fault in supervisor mode
trap type 6 code 0 rip ffffffff8087c932 cs 8 rflags 10246 cr2 36 ilevel 0 rsp fffffe8116c25c48
curlwp 0xfffffe8116a8c1c0 pid 0.65 lowest kstack 0xfffffe8116c232c0
kernel: page fault trap, code=0
Stopped in pid 0.65 (system) at netbsd:vmem_alloc+0x3f: movq   0(%rax),%rdi
db{1}> bt
vmem_alloc() at netbsd:vmem_alloc+0x3f
uvm_km_kmem_alloc() at netbsd:uvm_km_kmem_alloc+0x46
kmem_intr_alloc() at netbsd:kmem_intr_alloc+0x6d
usbd_set_config_index() at netbsd:usbd_set_config_index+0x27f
usbd_probe_and_attack() at netbsd:usbd_probe_and_attack+0xaa
usbd_new_device() at netbsd:usbd_new_device+0x417
uhub_explore() at netbsd:uhub_explore+0x2c1
uhub_explore() at netbsd:uhub_explore+0x9d
usb_discover.isra.0() at netbsd:usb_discover.isra.0+0x3e
usb_event_thread() at netbsd:usb_event_thread+0x74
db{1}> 

I did not observe this with the former USB stack (eg before the
nick-nhusb merge).

I believe this happens independently of setting the BIOS to forcing
visibility of the controller in USB 2.0 or 3.0 mode to the OS.
>How-To-Repeat:
Connect an urndis(4) device past boot time. Repeat a couple times if
there is no instant crash. This may otherwise be related to the multiple
"USB personalities" of the device (eg switching the USB mode after
connecting, as on most smartphones).
>Fix:
Currently unknown.