FYI, we noticed the following commit (built with gcc-7):

commit: b1ff47aacea95e5be1bedf2aee740395b52f4591 ("[PATCH 5/5] x86/kernel: jump_table: use relative references")
url: https://github.com/0day-ci/linux/commits/Ard-Biesheuvel/add-support-for-relative-references-in-jump-tables/20180628-021246


in testcase: boot

on test machine: qemu-system-i386 -enable-kvm -m 360M

caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):


+-----------------------------------------------------+------------+------------+
|                                                     | 1843c4017f | b1ff47aace |
+-----------------------------------------------------+------------+------------+
| boot_successes                                      | 57         | 46         |
| boot_failures                                       | 2          | 14         |
| Mem-Info                                            | 2          | 3          |
| invoked_oom-killer:gfp_mask=0x                      | 1          | 3          |
| Out_of_memory:Kill_process                          | 1          | 3          |
| WARNING:at_kernel/jump_label.c:#__jump_label_update | 0          | 11         |
| EIP:__jump_label_update                             | 0          | 11         |
+-----------------------------------------------------+------------+------------+



[   43.154660] WARNING: CPU: 0 PID: 351 at kernel/jump_label.c:388 __jump_label_update+0x101/0x130
[   43.172391] Modules linked in:
[   43.176312] CPU: 0 PID: 351 Comm: trinity-main Not tainted 4.18.0-rc2-00124-gb1ff47a #206
[   43.186389] EIP: __jump_label_update+0x101/0x130
[   43.192131] Code: a5 bf fd ff 6a 01 31 c9 ba 01 00 00 00 b8 c0 02 cd b1 c6 05 ba 2e cb b1 01 e8 8b bf fd ff ff 33 68 8b 35 b2 b1 e8 cf 74 f3 ff <0f> 0b 6a 01 31 c9 ba 01 00 00 00 b8 a8 02 cd b1 e8 6a bf fd ff 83 
[   43.215879] EAX: 00000021 EBX: b1cb67b0 ECX: 00000000 EDX: 00000000
[   43.223498] ESI: b1cb67b8 EDI: b1cb2fbc EBP: b89c9dc0 ESP: b89c9d9c
[   43.231212] DS: 007b ES: 007b FS: 0000 GS: 00e0 SS: 0068 EFLAGS: 00010292
[   43.239602] CR0: 80050033 CR2: 0805a000 CR3: 08979000 CR4: 00000690
[   43.247344] Call Trace:
[   43.250614]  jump_label_update+0x95/0x120
[   43.255705]  static_key_slow_inc_cpuslocked+0xcd/0xe0
[   43.261993]  static_key_slow_inc+0xd/0x10
[   43.266986]  tracepoint_probe_register_prio+0x257/0x320
[   43.273467]  tracepoint_probe_register+0xf/0x20
[   43.279104]  trace_event_reg+0x90/0x100
[   43.283964]  perf_trace_init+0x222/0x280
[   43.288833]  perf_tp_event_init+0x1d/0x50
[   43.293947]  perf_try_init_event+0x27/0xb0
[   43.299066]  perf_event_alloc+0x757/0xb20
[   43.304996]  __do_sys_perf_event_open+0x3de/0xd60
[   43.310932]  sys_perf_event_open+0x17/0x20
[   43.315362]  do_int80_syscall_32+0x98/0x1f0
[   43.319354]  entry_INT80_32+0x33/0x33
[   43.322816] EIP: 0xa7fa41b2
[   43.325381] Code: 89 c2 31 c0 89 d7 f3 aa 8b 44 24 1c 89 30 c6 40 04 00 83 c4 2c 89 f0 5b 5e 5f 5d c3 90 90 90 90 90 90 90 90 90 90 90 90 cd 80 <c3> 8d b6 00 00 00 00 8d bc 27 00 00 00 00 8b 1c 24 c3 8d b6 00 00 
[   43.346022] EAX: ffffffda EBX: 080d3000 ECX: 0000015f EDX: ffffffff
[   43.355195] ESI: ffffffff EDI: 00000001 EBP: 00000000 ESP: af819388
[   43.362426] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 007b EFLAGS: 00000282
[   43.368681] ---[ end trace 323a8199e30cb153 ]---


To reproduce:

        git clone https://github.com/intel/lkp-tests.git
        cd lkp-tests
        bin/lkp qemu -k <bzImage> job-script # job-script is attached in this email



Thanks,
Xiaolong