Hi, mm list, I hit panic with test with latest mmots v5.13-rc1-mmots-2021-05-13-17-23. It can constantly reproduce with userfaultfd selftest: $ sudo ./userfaultfd shmem 100 100 [...] testing events (fork, remap, remove): <PANIC> dmesg: [ 220.345061] userfaultfd: Corrupted page table at address 7f2309922028 [ 220.345066] PGD 12d6d9067 P4D 12d6d9067 PUD 12d87d067 PMD ffec71fb14c00067 [ 220.345069] BAD [ 220.345070] Bad pagetable: 000d [#1] SMP NOPTI [ 220.345072] CPU: 1 PID: 7467 Comm: userfaultfd Kdump: loaded Not tainted 5.13.0-rc1-mm1 #5 [ 220.345074] Hardware name: LENOVO 20NYS41L08/20NYS41L08, BIOS N2JET77W (1.55 ) 08/13/2019 [ 220.345075] RIP: 0033:0x404f10 [ 220.345078] Code: 65 00 00 00 00 00 00 e9 db 00 00 00 48 8b 15 9f 65 00 00 48 8b 05 48 65 00 00 48 0f af 45 f8 48 83 c0 2f 48 01 d0 48 83 e0 f8 <48> 8b 00 48 89 45 c0 48 8b 15 52 65 00 00 48 8b 45 f8 48 c1 e0 03 [ 220.345080] RSP: 002b:00007ffe3998a4b0 EFLAGS: 00010206 [ 220.345082] RAX: 00007f2309922028 RBX: 00007ffe3998a750 RCX: 00007f230cc2659e [ 220.345083] RDX: 00007f2306722000 RSI: 0000000006400000 RDI: 00007f22f9f22000 [ 220.345084] RBP: 00007ffe3998a5b0 R08: 00007f2306722000 R09: 00007f230cd78000 [ 220.345085] R10: 0000000000000003 R11: 0000000000000202 R12: 00000000004023c0 [ 220.345086] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 220.345088] FS: 00007f230cb22740 GS: 0000000000000000 I also hit once when building the kernel (with gcc): [ 834.470777] gcc: Corrupted page table at address 7fe0ba000000 [ 834.470787] PGD 240223067 P4D 240223067 PUD 269bb0067 PMD ffe8196b54840067 [ 834.470792] BAD [ 834.470796] Bad pagetable: 000d [#1] SMP NOPTI [ 834.470801] CPU: 1 PID: 32938 Comm: gcc Kdump: loaded Not tainted 5.13.0-rc1-mm1 #5 [ 834.470806] Hardware name: LENOVO 20NYS41L08/20NYS41L08, BIOS N2JET77W (1.55 ) 08/13/2019 [ 834.470808] RIP: 0033:0x55a777007d4b [ 834.470815] Code: 0c 03 75 17 b9 09 00 00 00 48 89 ee 48 8d 3d e7 fa 00 00 f3 a6 0f 84 c4 03 00 00 48 83 c5 01 48 3b 6c 24 10 0f 83 65 01 00 00 <0f> b6 45 00 3c 23 75 bd 0f b6 55 01 80 fa 20 0f 84 90 02 00 00 80 [ 834.470819] RSP: 002b:00007fffc38aa5d0 EFLAGS: 00010283 [ 834.470822] RAX: 0000000000000065 RBX: 00007fffc38aa870 RCX: 000000055a778202 [ 834.470825] RDX: 0000000000000001 RSI: 000055a7781c6010 RDI: 0000000000000007 [ 834.470828] RBP: 00007fe0ba000000 R08: 000055a778202540 R09: 00000000fffffffb [ 834.470831] R10: 000000001ec8b883 R11: 000000007f4a1f5b R12: 0000000000000001 [ 834.470833] R13: 00007fe0b9fffe3d R14: 000055a778202540 R15: 00007fe0ba2cace7 [ 834.470836] FS: 00007fe0ba8cb740 GS: 0000000000000000 I figured I'd better report before digging into anything.. Am I the only one here? Thanks, -- Peter Xu
