FYI, we noticed the following commit: commit: 218b5608bd466321e4fad5ac79f1e7e83babb55c ("mm: Copy accessing sub-page last when copy huge page") git://bee.sh.intel.com/git/yhuang/linux.git clear_huge_page_hint in testcase: boot on test machine: qemu-system-x86_64 -enable-kvm -cpu kvm64,+ssse3 -smp 2 -m 8G caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): +------------------------------------------+------------+------------+ | | e5e26c744d | 218b5608bd | +------------------------------------------+------------+------------+ | boot_successes | 8 | 0 | | boot_failures | 0 | 8 | | kernel_BUG_at_mm/memory.c | 0 | 8 | | invalid_opcode:#[##] | 0 | 8 | | Kernel_panic-not_syncing:Fatal_exception | 0 | 8 | +------------------------------------------+------------+------------+ [ 87.242100] kernel BUG at mm/memory.c:4382! [ 87.242127] invalid opcode: 0000 [#1] SMP [ 87.242129] Modules linked in: sr_mod cdrom sg ata_generic [ 87.242164] CPU: 0 PID: 5980 Comm: dpkg Not tainted 4.12.0-mm1-00396-g218b560 #1 [ 87.242166] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-20161025_171302-gandalf 04/01/2014 [ 87.242191] task: ffff8802064f1900 task.stack: ffffc9000246c000 [ 87.242223] RIP: 0010:copy_user_huge_page+0x1e6/0x4e7 [ 87.242226] RSP: 0000:ffffc9000246fce8 EFLAGS: 00010206 [ 87.242230] RAX: 000000fe47000200 RBX: ffffea0007bf8000 RCX: ffff88022a359600 [ 87.242254] RDX: 000000fe47000200 RSI: 000000000000111c RDI: ffffffff81e60378 [ 87.242257] RBP: ffffc9000246fd28 R08: 0000000000000200 R09: 000000fe471d3000 [ 87.242260] R10: 0000000000240000 R11: 0000000000000000 R12: ffffea0007bd8000 [ 87.242263] R13: 0000000000000200 R14: 000000fe47000000 R15: 00000000000342ca [ 87.242288] FS: 00007ff9cdd61800(0000) GS:ffff88023fc00000(0000) knlGS:0000000000000000 [ 87.242291] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 87.242294] CR2: 000000fe471d3d88 CR3: 00000001fbf47000 CR4: 00000000000006f0 [ 87.242324] Call Trace: [ 87.242355] ? mem_cgroup_try_charge+0x10c/0x1d9 [ 87.242360] do_huge_pmd_wp_page+0x431/0xdaa [ 87.242388] __handle_mm_fault+0x38f/0xecf [ 87.242394] ? __do_page_fault+0x33e/0x3e5 [ 87.242420] handle_mm_fault+0x108/0x192 [ 87.242424] __do_page_fault+0x20e/0x3e5 [ 87.242450] trace_do_page_fault+0x51/0xde [ 87.242456] do_async_page_fault+0x31/0x5d [ 87.242486] async_page_fault+0x28/0x30 [ 87.242490] RIP: 0033:0x7ff9cd5f5aa4 [ 87.242492] RSP: 002b:00007ffff3b043e0 EFLAGS: 00010297 [ 87.242517] RAX: 000000fe471d3d70 RBX: 0000000000000020 RCX: 00000000ffffffdf [ 87.242520] RDX: 00007ff9cd91ab78 RSI: 000000004112fecc RDI: 0000000000000000 [ 87.242522] RBP: 00007ff9cd91abc8 R08: 0000000000000060 R09: 000000fe471d3d30 [ 87.242546] R10: 00007ff9cd103270 R11: 0000000000000202 R12: 00007ff9cd91ab78 [ 87.242548] R13: 0000000000000040 R14: 000000fe471d3d30 R15: 00007ff9cd91ab20 [ 87.242552] Code: d0 e8 4d 70 f1 ff e8 c8 98 8a 00 4c 8b 4d d0 44 89 ea 4d 39 ce 4c 89 c8 49 0f 43 c6 4c 01 f2 48 39 d0 48 0f 47 c2 49 39 c1 74 02 <0f> 0b 4d 29 f1 49 c1 e9 0c 47 8d 3c 09 44 89 4d d0 45 39 fd 0f [ 87.242844] RIP: copy_user_huge_page+0x1e6/0x4e7 RSP: ffffc9000246fce8 [ 87.242872] ---[ end trace 6c914266bd80f149 ]--- To reproduce: git clone https://github.com/01org/lkp-tests.git cd lkp-tests bin/lkp qemu -k <bzImage> job-script # job-script is attached in this email Thanks, Kernel Test Robot