PANIC: vm_page_fault: unhandled page fault in kernel space at 0xdeadbefb, ip 0x80037c47 when rapidly mount/unmounting a volume

[anevilyak]

If I quickly mount/unmount a BFS volume (easiest way for me was cmd+m/cmd+u in DriveSetup), I get the following kernel panic every single time.

stack trace for thread 210 "bfs block allocator"
    kernel stack: 0xa105b000 to 0xa105f000
frame            caller     <image>:function + offset
 0 a105eac4 (+  48) 800564d5   <kernel>:invoke_debugger_command + 0x00ed
 1 a105eaf4 (+  64) 800562cd   <kernel>:invoke_pipe_segment__FP21debugger_command_pipelPc + 0x0079
 2 a105eb34 (+  64) 80056615   <kernel>:invoke_debugger_command_pipe + 0x009d
 3 a105eb74 (+  48) 800574f0   <kernel>:_ParseCommandPipe__16ExpressionParserRi + 0x0234
 4 a105eba4 (+  48) 80056ea6   <kernel>:EvaluateCommand__16ExpressionParserPCcRi + 0x01de
 5 a105ebd4 (+ 224) 800588bc   <kernel>:evaluate_debug_command + 0x0088
 6 a105ecb4 (+  64) 80054ab2   <kernel>:kernel_debugger_loop__Fv + 0x017a
 7 a105ecf4 (+  48) 800554e3   <kernel>:kernel_debugger + 0x0117
 8 a105ed24 (+ 192) 800553c1   <kernel>:panic + 0x0029
 9 a105ede4 (+  64) 800a62fd   <kernel>:vm_page_fault + 0x00b1
10 a105ee24 (+  64) 800b304d   <kernel>:page_fault_exception + 0x00b1
11 a105ee64 (+  12) 800b65a6   <kernel>:int_bottom + 0x0036 (nearest)
iframe at 0xa105ee70 (end = 0xa105eec8)
 eax 0x1            ebx 0xdeadbef3      ecx 0x915894c0   edx 0xd2
 esi 0xd2           edi 0x19d9c         ebp 0xa105eed8   esp 0xa105eea4
 eip 0x80037c47  eflags 0x10202
 vector: 0xe, error code: 0x0
12 a105ee70 (+ 104) 80037c47   <kernel>:recursive_lock_lock + 0x003f
13 a105eed8 (+  48) 8079ba3f   <bfs>:Lock__7JournalP11Transaction + 0x0023
14 a105ef08 (+  48) 8079be05   <bfs>:Start__11TransactionP6Volumex + 0x0035
15 a105ef38 (+ 160) 8078886e   <bfs>:_Initialize__14BlockAllocatorP14BlockAllocator + 0x032e
16 a105efd8 (+  32) 8004c7bf   <kernel>:_create_kernel_thread_kentry__Fv + 0x001b
17 a105eff8 (+1593446408) 8004c75c   <kernel>:thread_kthread_exit__Fv + 0x0000
kdebug>

[axeld]

Fixed in r26679.