Re: [LKP] Re: 87c4696d57 ("mm/debug: Add tests validating architecture page .."): [ 1.395296] kernel BUG at include/linux/mm.h:2007!

Rong Chen
2020-01-07T06:30:41Z

On 1/7/20 1:57 PM, Anshuman Khandual wrote:
> On 12/26/2019 02:19 PM, kernel test robot wrote:
>> 46cf053efe Linux 5.5-rc3
>> 87c4696d57 mm/debug: Add tests validating architecture page table helpers
>> +------------------------------------------+----------+------------+
>> | | v5.5-rc3 | 87c4696d57 |
>> +------------------------------------------+----------+------------+
>> | boot_successes | 32 | 0 |
>> | boot_failures | 0 | 11 |
>> | kernel_BUG_at_include/linux/mm.h | 0 | 11 |
>> | invalid_opcode:#[##] | 0 | 11 |
>> | EIP:pgtable_pmd_page_dtor | 0 | 11 |
>> | Kernel_panic-not_syncing:Fatal_exception | 0 | 11 |
>> +------------------------------------------+----------+------------+
>>
>> If you fix the issue, kindly add following tag
>> Reported-by: kernel test robot <lkp@intel.com>
>>
>> [ 1.390624] smp: Brought up 1 node, 2 CPUs
>> [ 1.390624] smpboot: Max logical packages: 2
>> [ 1.390624] smpboot: Total of 2 processors activated (8783.48 BogoMIPS)
>> [ 1.391537] debug_vm_pgtable: debug_vm_pgtable: Validating architecture page table helpers
>> [ 1.392382] page:f29b85c0 refcount:0 mapcount:0 mapping:00000000 index:0x0
>> [ 1.393415] raw: 02800000 f29b8624 f29b8584 00000000 00000000 edc22280 ffffffff 00000000
>> [ 1.394178] page dumped because: VM_BUG_ON_PAGE(page->pmd_huge_pte)
>> [ 1.394820] ------------[ cut here ]------------
>> [ 1.395296] kernel BUG at include/linux/mm.h:2007!
>> [ 1.395942] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC PTI
>> [ 1.396463] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.5.0-rc3-00001-g87c4696d57b5e #1
>> [ 1.396722] EIP: pgtable_pmd_page_dtor+0x1a/0x23
>> [ 1.396722] Code: d4 8a 27 c2 e8 16 81 04 00 b2 01 5b 88 d0 5d c3 55 89 e5 52 89 45 fc 8b 45 fc 83 78 08 00 74 0c ba e1 e2 e0 c1 e8 14 99 13 00 <0f> 0b e8 92 eb 13 00 c9 c3 55 89 e5 52 89 45 fc 8b 45 fc 90 8d 74
>> [ 1.396722] EAX: c1e0e2e1 EBX: 2dc2e000 ECX: 00000000 EDX: c1e0e2e1
>> [ 1.396722] ESI: edc2b000 EDI: edc4e010 EBP: ee287f14 ESP: ee287f10
>> [ 1.396722] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00010246
>> [ 1.396722] CR0: 80050033 CR2: ffffffff CR3: 0226a000 CR4: 001406b0
>> [ 1.396722] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
>> [ 1.396722] DR6: fffe0ff0 DR7: 00000400
>> [ 1.396722] Call Trace:
>> [ 1.396722] mop_up_one_pmd+0x48/0x62
>> [ 1.396722] pgd_free+0x35/0xe0
>> [ 1.396722] __mmdrop+0x42/0x96
>> [ 1.396722] debug_vm_pgtable+0x460/0x47c
>> [ 1.396722] kernel_init_freeable+0x84/0x172
>> [ 1.396722] ? rest_init+0xe9/0xe9
>> [ 1.396722] kernel_init+0xd/0xe9
>> [ 1.396722] ret_from_fork+0x1e/0x28
>> [ 1.396722] Modules linked in:
>> [ 1.396742] ---[ end trace 9c6f11143a94c590 ]---
>> [ 1.397197] EIP: pgtable_pmd_page_dtor+0x1a/0x23
> Hello,
>
> Wondering if some one could help me with steps to reproduce this crash ?
> Could not reproduce the problem with the patch applied on Linux 5.5-rc3
> when built with the config file provided here on a standard KVM guest.
>
> - Anshuman

Hi Anshuman,

You can compile the kernel with config-5.5.0-rc3-00001-g87c4696d57b5e,
and run the reproduce script.
Both files are in the original report mail.

#
./reproduce-yocto-vm-yocto-f91855057302-20191226051639-i386-randconfig-a001-20191225-5.5.0-rc3-00001-g87c4696d57b5e-1
~/linux/arch/x86/boot/bzImage 2>&1 | tail -20
[    1.471128] Call Trace:
[    1.471128]  mop_up_one_pmd+0x48/0x62
[    1.471128]  pgd_free+0x33/0xcc
[    1.471128]  __mmdrop+0x42/0x96
[    1.471128]  debug_vm_pgtable+0x45d/0x465
[    1.471128]  kernel_init_freeable+0x83/0x16b
[    1.471128]  ? rest_init+0xe0/0xe0
[    1.471128]  kernel_init+0xd/0xe9
[    1.471128]  ret_from_fork+0x1e/0x28
[    1.471128] Modules linked in:
[    1.471134] ---[ end trace b241750e0a95311e ]---
[    1.471570] EIP: pgtable_pmd_page_dtor+0x1a/0x23
[    1.472006] Code: ba 9b 0b df c1 e8 eb 71 04 00 5b 89 f0 5e 5d c3 55
89 e5 52 89 45 fc 8b 45 fc 83 78 08 00 74 0c ba b6 0b df c1 e8 d6 51 13
00 <0f> 0b e8 c6 a3 13 00 c9 c3 55 89 e5 52 89 45 fc 8b 45 fc 90 8d 74
[    1.473746] EAX: c1df0bb6 EBX: 2e42d000 ECX: 00000000 EDX: c1df0bb6
[    1.474340] ESI: ee42b000 EDI: ee44e008 EBP: eea87f20 ESP: eea87f1c
[    1.474465] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00010246
[    1.475112] CR0: 80050033 CR2: ffffffff CR3: 02242000 CR4: 001406b0
[    1.475712] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
[    1.476299] DR6: fffe0ff0 DR7: 00000400
[    1.476661] Kernel panic - not syncing: Fatal exception

Best Regards,
Rong Chen