df4684: === mode 2: rcu_barrier() no-op vs module unload ===
drm: expand RCU cpu 0 to 16
df4684: call_rcu enqueued (callback 0xffffffff831dd020 fires in >=1s)
df4684: rcu_barrier() returned (no-op on this port) — kldunload NOW; the pending callback will execute into unmapped module text ~1s later
df4684: === mode 2 armed — run: kldunload df4684; sleep 3 ===
df4684: unloading


Fatal trap 12: page fault while in kernel mode
cpuid = 0; lapic id = 0
fault virtual address	= 0xffffffff831dd020
fault code		= supervisor read instruction, page not present
instruction pointer	= 0x8:0xffffffff831dd020
stack pointer	        = 0x10:0xfffff8008974b9a8
frame pointer	        = 0x10:0xfffff8008974b9d0
code segment		= base 0x0, limit 0xfffff, type 0x1b
			= DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags	= interrupt enabled, resume, IOPL = 0
current process		= Idle
current thread          = pri 12 (CRIT)
kernel: type 12 trap, code=10

CPU0 stopping CPUs: 0x0000003e
 stopped
Stopped at      iicbus_devclass+0x1e348:

Fatal trap 12: page fault while in kernel mode
cpuid = 0; lapic id = 0
fault virtual address	= 0xffffffff831dd020
fault code		= supervisor read data, page not present
instruction pointer	= 0x8:0xffffffff80bccb70
stack pointer	        = 0x10:0xfffff8008974b640
frame pointer	        = 0x10:0xfffff8008974b668
code segment		= base 0x0, limit 0xfffff, type 0x1b
			= DPL 0, pres 1, long 0, def32 0, gran 1
processor eflags	= interrupt enabled, resume, IOPL = 0
current process		= Idle
current thread          = pri 12 (CRIT)
        kernel: type 12 trap, code=0
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