bisecting fixing commit since 1bab61d3e8cd96f2badf515dcb06e4e1029bc017 building syzkaller on 4afdfa205b55633e7eb9db03a9d099d7aa324801 testing commit 1bab61d3e8cd96f2badf515dcb06e4e1029bc017 with gcc (GCC) 8.4.1 20210217 kernel signature: 3de7e7d08d72cc49406a785f2566254f49d3d96c9eccf0b916626edc1d97381c run #0: crashed: kernel BUG in __handle_mm_fault run #1: crashed: kernel BUG in __handle_mm_fault run #2: crashed: kernel BUG in __handle_mm_fault run #3: crashed: kernel BUG in __handle_mm_fault run #4: crashed: kernel BUG in __handle_mm_fault run #5: crashed: kernel BUG in __handle_mm_fault run #6: crashed: kernel BUG in __handle_mm_fault run #7: crashed: kernel BUG in __handle_mm_fault run #8: crashed: kernel BUG in __handle_mm_fault run #9: crashed: kernel BUG in __handle_mm_fault run #10: crashed: kernel BUG in __handle_mm_fault run #11: crashed: kernel BUG in __handle_mm_fault run #12: crashed: kernel BUG in __handle_mm_fault run #13: crashed: kernel BUG in __handle_mm_fault run #14: crashed: kernel BUG in __handle_mm_fault run #15: crashed: kernel BUG in __handle_mm_fault run #16: crashed: kernel BUG in __handle_mm_fault run #17: crashed: kernel BUG in __handle_mm_fault run #18: crashed: kernel BUG in corrupted run #19: crashed: kernel BUG in __handle_mm_fault testing current HEAD eb575cd5d7f60241d016fdd13a9e86d962093c9b testing commit eb575cd5d7f60241d016fdd13a9e86d962093c9b with gcc (GCC) 8.4.1 20210217 kernel signature: 3e023f84e75f0a97ed320196354838b6abe85750714592db85765e5f87e96ccf run #0: crashed: kernel BUG in __handle_mm_fault run #1: crashed: kernel BUG in __handle_mm_fault run #2: crashed: kernel BUG in corrupted run #3: crashed: kernel BUG in __handle_mm_fault run #4: crashed: kernel BUG in __handle_mm_fault run #5: crashed: kernel BUG in __handle_mm_fault run #6: crashed: kernel BUG in __handle_mm_fault run #7: crashed: kernel BUG in __handle_mm_fault run #8: crashed: kernel BUG in __handle_mm_fault run #9: crashed: kernel BUG in __handle_mm_fault revisions tested: 2, total time: 30m21.509662423s (build: 23m10.03096228s, test: 6m34.762342614s) the crash still happens on HEAD commit msg: Linux 4.19.195 crash: kernel BUG in __handle_mm_fault batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 ------------[ cut here ]------------ batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! kernel BUG at mm/memory.c:4040! invalid opcode: 0000 [#1] PREEMPT SMP KASAN IPv6: ADDRCONF(NETDEV_UP): batadv_slave_0: link is not ready CPU: 0 PID: 7134 Comm: syz-executor.0 Not tainted 4.19.195-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:wp_huge_pmd mm/memory.c:4040 [inline] RIP: 0010:__handle_mm_fault+0x2192/0x4100 mm/memory.c:4248 Code: 00 00 00 4c 89 f7 e8 2d f0 09 00 f0 41 ff 0e 0f 85 54 ec ff ff 48 89 df e8 9b e8 f5 ff e9 47 ec ff ff 48 89 df e8 48 5d 3b 05 <0f> 0b 49 8d 84 24 60 ff ff ff 48 89 c7 e8 1c d9 0b 00 41 89 c7 e9 RSP: 0018:ffff8881daf87cc8 EFLAGS: 00010296 RAX: 0000000000000137 RBX: ffff8881db1f7eb0 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8767a0c0 RDI: ffffffff8a193aa0 RBP: ffff8881daf87de8 R08: ffffed103ed05081 R09: ffffed103ed05080 R10: ffffed103ed05080 R11: ffff8881f6828407 R12: ffff8881daf87dc0 R13: 1ffff1103b5f0fa0 R14: ffffffff87311120 R15: 0000000000000080 FS: 000000000249b400(0000) GS:ffff8881f6800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055afd605d998 CR3: 00000001da8c0004 CR4: 00000000001606f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: handle_mm_fault+0x3dd/0x8b0 mm/memory.c:4295 __do_page_fault+0x50e/0xb30 arch/x86/mm/fault.c:1412 do_page_fault+0x64/0x3b0 arch/x86/mm/fault.c:1487 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1205 RIP: 0033:0x45fb08 Code: d1 f3 a4 c3 80 fa 10 73 17 80 fa 08 73 27 80 fa 04 73 33 80 fa 01 77 3b 72 05 0f b6 0e 88 0f c3 c5 fa 6f 06 c5 fa 6f 4c 16 f0 fa 7f 07 c5 fa 7f 4c 17 f0 c3 48 8b 4c 16 f8 48 8b 36 48 89 4c RSP: 002b:00007ffdd40ee1b8 EFLAGS: 00010206 RAX: 00000000200001c0 RBX: 000000000055c900 RCX: 0000000000960000 RDX: 0000000000000013 RSI: 0000000000560398 RDI: 00000000200001c0 RBP: 00007ffdd40ee258 R08: 0000000000560278 R09: 0000000000000000 R10: 00007ffdd40ee270 R11: 0000000000000246 R12: 00000000000003e8 R13: 000000000055c04c R14: 000000000055bf00 R15: 000000000055c040 Modules linked in: ---[ end trace 06a9fda0bcfbc81c ]--- batman_adv: batadv0: Interface activated: batadv_slave_0 RIP: 0010:wp_huge_pmd mm/memory.c:4040 [inline] RIP: 0010:__handle_mm_fault+0x2192/0x4100 mm/memory.c:4248 Code: 00 00 00 4c 89 f7 e8 2d f0 09 00 f0 41 ff 0e 0f 85 54 ec ff ff 48 89 df e8 9b e8 f5 ff e9 47 ec ff ff 48 89 df e8 48 5d 3b 05 <0f> 0b 49 8d 84 24 60 ff ff ff 48 89 c7 e8 1c d9 0b 00 41 89 c7 e9 IPv6: ADDRCONF(NETDEV_UP): veth1_to_batadv: link is not ready RSP: 0018:ffff8881daf87cc8 EFLAGS: 00010296 batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 RAX: 0000000000000137 RBX: ffff8881db1f7eb0 RCX: 0000000000000000 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! RDX: 0000000000000000 RSI: ffffffff8767a0c0 RDI: ffffffff8a193aa0 batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 RBP: ffff8881daf87de8 R08: ffffed103ed05081 R09: ffffed103ed05080 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! R10: ffffed103ed05080 R11: ffff8881f6828407 R12: ffff8881daf87dc0 batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 R13: 1ffff1103b5f0fa0 R14: ffffffff87311120 R15: 0000000000000080 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! FS: 000000000249b400(0000) GS:ffff8881f6900000(0000) knlGS:0000000000000000 batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3d) already exists on: batadv_slave_0 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems! CR2: 00007ffcc66cbc00 CR3: 00000001da8c0001 CR4: 00000000001606e0 IPv6: ADDRCONF(NETDEV_UP): batadv_slave_0: link is not ready DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 batman_adv: batadv0: Interface activated: batadv_slave_0 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 IPv6: ADDRCONF(NETDEV_CHANGE): macvlan1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): macsec0: link becomes ready