FYI, we noticed the below changes on(TBH, I don't know the bisect is
correct or not; sorry for the noise if not)

git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux.git lsm/stacking
commit 58c4f9e3be81a85839ea229b1dd36bf55232d440 ("LSM: Refactor existing LSM stacking")


+------------------------------------------------+------------+------------+
|                                                | c9979f3c6e | 58c4f9e3be |
+------------------------------------------------+------------+------------+
| boot_successes                                 | 15         | 0          |
| early-boot-hang                                | 1          |            |
| boot_failures                                  | 0          | 15         |
| Kernel_panic-not_syncing:No_working_init_found | 0          | 15         |
| backtrace:panic                                | 0          | 15         |
+------------------------------------------------+------------+------------+


[    3.437279] Starting init: /sbin/init exists but couldn't execute it (error -12)
[    3.438655] Starting init: /etc/init exists but couldn't execute it (error -13)
[    3.440136] Starting init: /bin/sh exists but couldn't execute it (error -12)
[    3.441487] Kernel panic - not syncing: No working init found.  Try passing init= option to kernel. See Linux Documentation/init.txt for guidance.
[    3.443352] CPU: 0 PID: 1 Comm: swapper Not tainted 3.18.0-rc4-g49aba53 #1949
[    3.443352]  00000000 f783d540 80017f88 8138c3bd 80017fa0 8138b30b 815e1f40 f783d540
[    3.443352]  815e1f40 00000000 80017fac 81389523 8152ab4d 80016000 813918e0 81389474
[    3.443352]  00000000 00000000 00000000 00000000 00000000 00000000 0000007b 0000007b
[    3.443352] Call Trace:
[    3.443352]  [<8138c3bd>] dump_stack+0x16/0x18
[    3.443352]  [<8138b30b>] panic+0x86/0x19e
[    3.443352]  [<81389523>] kernel_init+0xaf/0xb3
[    3.443352]  [<813918e0>] ret_from_kernel_thread+0x20/0x30
[    3.443352]  [<81389474>] ? rest_init+0xa2/0xa2
[    3.443352] Kernel Offset: 0x0 from 0x81000000 (relocation range: 0x80000000-0x947fdfff)

Elapsed time: 10



	--yliu