-CURRENT fatal trap cause by cxgbe module

[Dustin Marquess]

So I've been fighting with any current from the last month or so
instantly crashing when I boot it.  I did notice that kernels in the
various snapshot images were working, however, so I was trying to
figure out why.  At first I thought it was because I had INVARIANTS
and such disabled, but no, I finally figured it out.

I've had in my /boot/loader.conf for a while now:

if_cxgbe_load="YES"

I guess since the stock installer kernels don't have cxgbe enabled by
default.  I added "device cxgbe" to my kernels a while ago.  Normally
the kernel would give some error about the module already being loaded
or something and just continue.  As of last month or so, however,
instead it just crashes:

FreeBSD clang version 9.0.1 (git at github.com:llvm/llvm-project.git
c1a0a213378a458fbea1a5c77b315c7dce08fd05) (based on LLVM 9.0.1)
WARNING: WITNESS option enabled, expect reduced performance.
kernel trap 12 with interrupts disabled


Fatal trap 12: page fault while in kernel mode
cpuid = 0; apic id = 00
fault virtual address = 0x8
fault code = supervisor read data, page not present
instruction pointer = 0x20:0xffffffff80622931
stack pointer         = 0x28:0xffffffff8241c9a0
frame pointer         = 0x28:0xffffffff8241c9e0
code segment = base 0x0, limit 0xfffff, type 0x1b
= DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags = resume, IOPL = 0
current process = 0 ()
trap number = 12
panic: page fault
cpuid = 0
time = 1

KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xffffffff8241c600
vpanic() at vpanic+0x18a/frame 0xffffffff8241c660
panic() at panic+0x43/frame 0xffffffff8241c6c0
trap_fatal() at trap_fatal+0x386/frame 0xffffffff8241c720
trap_pfault() at trap_pfault+0x99/frame 0xffffffff8241c7a0
trap() at trap+0x4e9/frame 0xffffffff8241c8d0
calltrap() at calltrap+0x8/frame 0xffffffff8241c8d0
--- trap 0xc, rip = 0xffffffff80622931, rsp = 0xffffffff8241c9a0, rbp
= 0xffffffff8241c9e0 ---
malloc() at malloc+0x51/frame 0xffffffff8241c9e0
sysctl_handle_string() at sysctl_handle_string+0x12d/frame 0xffffffff8241ca20
sysctl_root_handler_locked() at sysctl_root_handler_locked+0xa2/frame
0xffffffff8241ca70
sysctl_register_oid() at sysctl_register_oid+0x54c/frame 0xffffffff8241cd80
sysctl_register_all() at sysctl_register_all+0x88/frame 0xffffffff8241cda0
mi_startup() at mi_startup+0xf2/frame 0xffffffff8241cdf0
btext() at btext+0x2c
KDB: enter: panic
[ thread pid 0 tid 0 ]
Stopped at      kdb_enter+0x37: movq    $0,0xa5f4a6(%rip)
db>

If I take the if_cxgbe_load out, however, it boots fine.

Thanks!
-Dustin