Greeting,

FYI, we noticed the following commit (built with gcc-9):

commit: a97a17109332c3a9e361553adfa383c1e5205f3b ("[PATCH V4 2/4] mm/debug_vm_pgtable: Add tests validating advanced arch page table helpers")
url: https://github.com/0day-ci/linux/commits/Anshuman-Khandual/mm-debug_vm_pgtable-Add-some-more-tests/20200706-085212
base: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git dcb7fd82c75ee2d6e6f9d8cc71c52519ed52e258

in testcase: boot

on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 16G

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


+---------------------------------------------+------------+------------+
|                                             | 30011bfca7 | a97a171093 |
+---------------------------------------------+------------+------------+
| boot_successes                              | 4          | 0          |
| boot_failures                               | 0          | 4          |
| BUG:unable_to_handle_page_fault_for_address | 0          | 4          |
| Oops:#[##]                                  | 0          | 4          |
| RIP:hugetlb_advanced_tests                  | 0          | 4          |
| Kernel_panic-not_syncing:Fatal_exception    | 0          | 4          |
+---------------------------------------------+------------+------------+


If you fix the issue, kindly add following tag
Reported-by: kernel test robot <redacted>


[   94.349598] BUG: unable to handle page fault for address: ffffed10a7ffddff
[   94.351039] #PF: supervisor read access in kernel mode
[   94.352172] #PF: error_code(0x0000) - not-present page
[   94.353256] PGD 43ffed067 P4D 43ffed067 PUD 43fdee067 PMD 0 
[   94.354484] Oops: 0000 [#1] SMP KASAN
[   94.355238] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.8.0-rc4-00002-ga97a17109332c #1
[   94.360456] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
[   94.361950] RIP: 0010:hugetlb_advanced_tests+0x137/0x699
[   94.363026] Code: 8b 13 4d 85 f6 75 0b 48 ff 05 2c e4 6a 01 31 ed eb 41 bf f8 ff ff ff ba ff ff 37 00 4c 01 f7 48 c1 e2 2a 48 89 f9 48 c1 e9 03 <80> 3c 11 00 74 05 e8 cd c0 67 fa ba f8 ff ff ff 49 8b 2c 16 48 85
[   94.366592] RSP: 0000:ffffc90000047d30 EFLAGS: 00010a06
[   94.367693] RAX: 1ffffffff1049b80 RBX: ffff888380525308 RCX: 1ffff110a7ffddff
[   94.369215] RDX: dffffc0000000000 RSI: 1ffff11087ffdc00 RDI: ffff88853ffeeff8
[   94.370693] RBP: 000000000018e510 R08: 0000000000000025 R09: 0000000000000001
[   94.372165] R10: ffff888380523c07 R11: ffffed10700a4780 R12: ffff88843208e510
[   94.373674] R13: 0000000000000025 R14: ffff88843ffef000 R15: 000031e01ae61000
[   94.375147] FS:  0000000000000000(0000) GS:ffff8883a3800000(0000) knlGS:0000000000000000
[   94.376883] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   94.378051] CR2: ffffed10a7ffddff CR3: 0000000004e15000 CR4: 00000000000406a0
[   94.379522] Call Trace:
[   94.380073]  debug_vm_pgtable+0xd81/0x2029
[   94.380871]  ? pmd_advanced_tests+0x621/0x621
[   94.381819]  do_one_initcall+0x1eb/0xbd0
[   94.382551]  ? trace_event_raw_event_initcall_finish+0x240/0x240
[   94.383634]  ? rcu_read_lock_sched_held+0xb9/0x110
[   94.388727]  ? rcu_read_lock_held+0xd0/0xd0
[   94.389604]  ? __kasan_check_read+0x1d/0x30
[   94.390485]  kernel_init_freeable+0x430/0x4f8
[   94.391416]  ? rest_init+0x3f8/0x3f8
[   94.392185]  kernel_init+0x14/0x1e8
[   94.392918]  ret_from_fork+0x22/0x30
[   94.393662] Modules linked in:
[   94.394289] CR2: ffffed10a7ffddff
[   94.395000] ---[ end trace 8ca5a1655dfb8c39 ]---


To reproduce:

        # build kernel
	cd linux
	cp config-5.8.0-rc4-00002-ga97a17109332c .config
	make HOSTCC=gcc-9 CC=gcc-9 ARCH=x86_64 olddefconfig prepare modules_prepare bzImage

        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,
lkp