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WARNING: CPU: 0 PID: 1465 at drivers/staging/android/ion/ion.c:132 ion_buffer_destroy+0xd4/0x190 drivers/staging/android/ion/ion.c:132
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 1465 Comm: ion_system_heap Not tainted 4.15.0-rc7+ #255
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 panic+0x1e4/0x41c kernel/panic.c:183
 __warn+0x1dc/0x200 kernel/panic.c:547
 report_bug+0x211/0x2d0 lib/bug.c:184
 fixup_bug.part.11+0x37/0x80 arch/x86/kernel/traps.c:178
 fixup_bug arch/x86/kernel/traps.c:247 [inline]
 do_error_trap+0x2d7/0x3e0 arch/x86/kernel/traps.c:296
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315
 invalid_op+0x22/0x40 arch/x86/entry/entry_64.S:1079
RIP: 0010:ion_buffer_destroy+0xd4/0x190 drivers/staging/android/ion/ion.c:132
RSP: 0018:ffff8801d3a1fd28 EFLAGS: 00010293
RAX: ffff8801d3a44680 RBX: ffff8801c0341700 RCX: ffffffff8410f1e4
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8801d3fe95f8
RBP: ffff8801d3a1fd50 R08: 0000000000000000 R09: 1ffff1003a743f8a
R10: ffff8801d3a1fc18 R11: 0000000000000000 R12: ffffffff86e47780
R13: ffff8801d3fe95c0 R14: ffff8801c0341720 R15: 0000000000000001
 ion_heap_deferred_free+0x290/0x650 drivers/staging/android/ion/ion_heap.c:245
 kthread+0x33c/0x400 kernel/kthread.c:238
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:524
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..