panic: trap: fast data access mmu miss

I've got a panic on sparc64 5.1-CURRENT #0: Wed Oct 15:

panic: trap: fast data access mmu miss
cpuid = 0;
Debugger("panic")
Stopped at      Debugger+0x1c:  ta              %xcc, 1
db> tr
panic() at panic+0x174
trap() at trap+0x394
-- fast data access mmu miss tar=0 %o7=0xc018b820 --
quotactl() at quotactl+0x98
syscall() at syscall+0x308
-- syscall (148, FreeBSD ELF64, quotactl) %o7=0x1e3044 --
userland() at 0x41187e88
user trace: trap %o7=0x1e3044
pc 0x41187e88, sp 0x7fdffffdf11
pc 0x15149c, sp 0x7fdffffe011
pc 0x151818, sp 0x7fdffffe561
pc 0x1c771c, sp 0x7fdffffe621
pc 0x1a64a4, sp 0x7fdffffe6f1
pc 0x1b3904, sp 0x7fdffffe971
pc 0x1d987c, sp 0x7fdffffeab1
pc 0x1d99c0, sp 0x7fdffffebb1
pc 0x1da06c, sp 0x7fdffffec91
pc 0x1db99c, sp 0x7fdffffed61
pc 0x451ea8, sp 0x7fdffffee51
pc 0x133560, sp 0x7fdfffff0e1
pc 0x405d3f94, sp 0x7fdfffff1a1
done

Thanks!