FYI, we noticed the below changes on

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git master
commit 6a7d22008b2294f1dacbc77632a26f2142f2d4b0 ("mm: Fix boot crash with f7426b983a6a ("mm: cma: adjust address limit to avoid hitting low/high memory boundary")")

The original boot failures are fixed, but there are some boot hang now.
Sometimes because of OOM for trinity test.

+----------------------+------------+------------+
|                      | 12db936a10 | 6a7d22008b |
+----------------------+------------+------------+
| boot_successes       | 0          | 2          |
| boot_failures        | 20         | 11         |
| BUG:Int#:CR2(null)   | 20         |            |
| BUG:kernel_boot_hang | 0          | 11         |
+----------------------+------------+------------+


[  400.841527] ??? Writer stall state 8 g945 c944 f0x0
[  400.841532] rcu_sched: wait state: 2 ->state: 0x0
[  400.841536] rcu_bh: wait state: 1 ->state: 0x1
[  440.699265] INFO: rcu_sched detected stalls on CPUs/tasks: { 1} (detected by 0, t=10002 jiffies, g=945, c=944, q=0)
[  440.699265] Task dump for CPU 1:
[  440.699265] swapper/0       R running   6008     1      0 0x00000008
[  440.699265]  00000050 d2145e4c cb4843c0 00000000 00000000 c8b08800 0000001e 00000005
[  440.699265]  d2034c00 c1e70600 00000001 d2145e44 c15c9465 00000001 00000001 0000001e
[  440.699265]  00000050 00000005 d2034c00 0000004f 00000000 d2145e54 c15c94a9 00000001
[  440.699265] Call Trace:
[  440.699265]  [<c15c9465>] ? scrup+0xb8/0xd3
[  440.699265]  [<c15c94a9>] ? lf+0x29/0x61
[  440.699265]  [<c15ca92f>] ? vt_console_print+0x1b2/0x2b6
[  440.699265]  [<c15ca77d>] ? con_stop+0x25/0x25
[  440.699265]  [<c107a4fa>] ? call_console_drivers+0x8c/0xbf
[  440.699265]  [<c107b255>] ? console_unlock+0x2e2/0x393
[  440.699265]  [<c107b729>] ? vprintk_emit+0x423/0x465
[  440.699265]  [<c1d681a1>] ? printk+0x1c/0x1e
[  440.699265]  [<c25dd311>] ? event_trace_self_tests+0x91/0x279
[  440.699265]  [<c25dd616>] ? test_work+0x57/0x57
[  440.699265]  [<c25dd616>] ? test_work+0x57/0x57
[  440.699265]  [<c25dd627>] ? event_trace_self_tests_init+0x11/0x5b
[  440.699265]  [<c25c4c7b>] ? do_one_initcall+0x15f/0x16e
[  440.699265]  [<c25c44d5>] ? repair_env_string+0x12/0x54
[  440.699265]  [<c105666f>] ? parse_args+0x1a6/0x286
[  440.699265]  [<c25c4d86>] ? kernel_init_freeable+0xfc/0x179
[  440.699265]  [<c1d664f6>] ? kernel_init+0xd/0xb8
[  440.699265]  [<c1d87801>] ? ret_from_kernel_thread+0x21/0x30
[  440.699265]  [<c1d664e9>] ? rest_init+0xaa/0xaa
[  460.838635] rcu-torture: rtc: c2e29fc0 ver: 1 tfle: 0 rta: 1 rtaf: 0 rtf: 0 rtmbe: 0 rtbke: 0 rtbre: 0 rtbf: 0 rtb: 0 nt: 1 onoff: 0/0:0/0 -1,0:-1,0 0:0 (HZ=100) barrier: 0/0:0 cbflood: 1
[  460.838654] rcu-torture: Reader Pipe:  2 0 0 0 0 0 0 0 0 0 0
[  460.838664] rcu-torture: Reader Batch:  2 0 0 0 0 0 0 0 0 0 0

Thanks,
Huang, Ying