bisecting fixing commit since 14cfdbd39e316efd91ae6e403ef8211f0b022603 building syzkaller on 84f999d6319b21d9567132bf7ed26507f6d24310 testing commit 14cfdbd39e316efd91ae6e403ef8211f0b022603 with gcc (GCC) 8.1.0 kernel signature: 37d9ac68a39857b5e8ee08e46355ea210c89d7f16809e52cfec93bed3aa14bf4 all runs: crashed: kernel BUG at mm/hugetlb.c:LINE! testing current HEAD a834132bd465f9d7f4049be65648e01cf2533cb8 testing commit a834132bd465f9d7f4049be65648e01cf2533cb8 with gcc (GCC) 8.1.0 kernel signature: 98d6ca3f339510193a7dc4bb973341e98617d0e88d6f850f63c802d31609da52 all runs: crashed: kernel BUG at mm/hugetlb.c:LINE! revisions tested: 2, total time: 27m8.423585818s (build: 19m23.241578273s, test: 6m1.046997265s) the crash still happens on HEAD commit msg: Linux 4.19.140 crash: kernel BUG at mm/hugetlb.c:LINE! overlayfs: failed to resolve './bus': -2 overlayfs: upper fs does not support tmpfile. overlayfs: upper fs does not support xattr, falling back to index=off and metacopy=off. overlayfs: failed to resolve './bus': -2 ------------[ cut here ]------------ kernel BUG at mm/hugetlb.c:3371! overlayfs: upper fs does not support tmpfile. overlayfs: upper fs does not support tmpfile. invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 7907 Comm: syz-executor.0 Not tainted 4.19.140-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 overlayfs: upper fs does not support xattr, falling back to index=off and metacopy=off. RIP: 0010:__unmap_hugepage_range+0x7cc/0x980 mm/hugetlb.c:3371 Code: 75 7f 48 83 3d bc 85 9b 06 00 74 22 4c 89 ff 48 89 da e8 c7 57 9b ff 66 90 4c 89 e7 e8 5d 50 4a 05 e9 82 fb ff ff 0f 0b 0f 0b <0f> 0b 0f 0b 0f 0b 48 89 cf e8 e6 db 02 00 e9 d5 fb ff ff 48 89 df RSP: 0018:ffff88808b52f708 EFLAGS: 00010206 RAX: 00000000001fffff RBX: 0000000020000000 RCX: 0000000000000009 RDX: 1ffffffff1433958 RSI: ffff88808b6ca670 RDI: ffffffff8a19cac0 RBP: ffff88808b52f870 R08: 0000000000000000 R09: fffffbfff1428ee0 R10: fffffbfff1428ee0 R11: 0000000000000001 R12: ffff88808b6196c0 R13: ffff88808b52f848 R14: ffffffff8a19cab0 R15: ffff88809174e680 FS: 00007f020385a700(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f53c0cf05e0 CR3: 000000008a284000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: overlayfs: upper fs does not support tmpfile. __unmap_hugepage_range_final+0xd/0x40 mm/hugetlb.c:3460 unmap_single_vma+0x1c1/0x300 mm/memory.c:1552 unmap_vmas+0xe7/0x1a0 mm/memory.c:1586 exit_mmap+0x251/0x470 mm/mmap.c:3091 __mmput kernel/fork.c:1015 [inline] mmput+0x107/0x3f0 kernel/fork.c:1036 overlayfs: upper fs does not support xattr, falling back to index=off and metacopy=off. exit_mm kernel/exit.c:546 [inline] do_exit+0x9cd/0x2dc0 kernel/exit.c:874 ------------[ cut here ]------------ kernel BUG at mm/hugetlb.c:3371! overlayfs: failed to resolve './bus': -2 do_group_exit+0xf4/0x2f0 kernel/exit.c:990 get_signal+0x313/0x1a30 kernel/signal.c:2588 do_signal+0x87/0x1960 arch/x86/kernel/signal.c:821 overlayfs: upper fs does not support tmpfile. exit_to_usermode_loop+0x114/0x200 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x413/0x4e0 arch/x86/entry/common.c:296 overlayfs: upper fs does not support xattr, falling back to index=off and metacopy=off. entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c8c9 Code: 2d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb b5 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f0203859cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 000000000076bfa8 RCX: 000000000045c8c9 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 000000000076bfac RBP: 000000000076bfa0 R08: 000000000000000e R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 000000000076bfac R13: 00007ffcf32601ff R14: 00007f020385a9c0 R15: 000000000076bfac Modules linked in: overlayfs: upper fs does not support xattr, falling back to index=off and metacopy=off. overlayfs: upper fs does not support tmpfile. overlayfs: failed to resolve './bus': -2 invalid opcode: 0000 [#2] PREEMPT SMP KASAN ---[ end trace 721c55ec9a20b43f ]--- CPU: 0 PID: 7924 Comm: syz-executor.2 Tainted: G D 4.19.140-syzkaller #0 RIP: 0010:__unmap_hugepage_range+0x7cc/0x980 mm/hugetlb.c:3371 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Code: 75 7f 48 83 3d bc 85 9b 06 00 74 22 4c 89 ff 48 89 da e8 c7 57 9b ff 66 90 4c 89 e7 e8 5d 50 4a 05 e9 82 fb ff ff 0f 0b 0f 0b <0f> 0b 0f 0b 0f 0b 48 89 cf e8 e6 db 02 00 e9 d5 fb ff ff 48 89 df RIP: 0010:__unmap_hugepage_range+0x7cc/0x980 mm/hugetlb.c:3371 Code: 75 7f 48 83 3d bc 85 9b 06 00 74 22 4c 89 ff 48 89 da e8 c7 57 9b ff 66 90 4c 89 e7 e8 5d 50 4a 05 e9 82 fb ff ff 0f 0b 0f 0b <0f> 0b 0f 0b 0f 0b 48 89 cf e8 e6 db 02 00 e9 d5 fb ff ff 48 89 df RSP: 0018:ffff88808e5e7708 EFLAGS: 00010206 RAX: 00000000001fffff RBX: 0000000020000000 RCX: 0000000000000009 RDX: 1ffffffff1433958 RSI: ffff888099acad68 RDI: ffffffff8a19cac0 RBP: ffff88808e5e7870 R08: 0000000000000000 R09: 0000000000000000 R10: ffffed10121393c3 R11: 0000000000000000 R12: ffff8880a9471840 R13: ffff88808e5e7848 R14: ffffffff8a19cab0 R15: ffff8880a973c700 FS: 00007f07a91c6700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000004d9448 CR3: 000000009f378000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __unmap_hugepage_range_final+0xd/0x40 mm/hugetlb.c:3460 unmap_single_vma+0x1c1/0x300 mm/memory.c:1552 unmap_vmas+0xe7/0x1a0 mm/memory.c:1586 exit_mmap+0x251/0x470 mm/mmap.c:3091 __mmput kernel/fork.c:1015 [inline] mmput+0x107/0x3f0 kernel/fork.c:1036 exit_mm kernel/exit.c:546 [inline] do_exit+0x9cd/0x2dc0 kernel/exit.c:874 do_group_exit+0xf4/0x2f0 kernel/exit.c:990 get_signal+0x313/0x1a30 kernel/signal.c:2588 do_signal+0x87/0x1960 arch/x86/kernel/signal.c:821 exit_to_usermode_loop+0x114/0x200 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x413/0x4e0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c8c9 Code: 2d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb b5 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f07a91c5cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 000000000076bfa8 RCX: 000000000045c8c9 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 000000000076bfac RBP: 000000000076bfa0 R08: 000000000000000e R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 000000000076bfac R13: 00007ffd44b9170f R14: 00007f07a91c69c0 R15: 000000000076bfac Modules linked in: overlayfs: failed to resolve './bus': -2 overlayfs: upper fs does not support tmpfile. ---[ end trace 721c55ec9a20b440 ]--- overlayfs: upper fs does not support xattr, falling back to index=off and metacopy=off. overlayfs: upper fs does not support xattr, falling back to index=off and metacopy=off. overlayfs: upper fs does not support tmpfile. RIP: 0010:__unmap_hugepage_range+0x7cc/0x980 mm/hugetlb.c:3371 overlayfs: failed to resolve './bus': -2 overlayfs: failed to resolve './bus': -2 overlayfs: upper fs does not support xattr, falling back to index=off and metacopy=off. Code: 75 7f 48 83 3d bc 85 9b 06 00 74 22 4c 89 ff 48 89 da e8 c7 57 9b ff 66 90 4c 89 e7 e8 5d 50 4a 05 e9 82 fb ff ff 0f 0b 0f 0b <0f> 0b 0f 0b 0f 0b 48 89 cf e8 e6 db 02 00 e9 d5 fb ff ff 48 89 df RSP: 0018:ffff88808b52f708 EFLAGS: 00010206 overlayfs: upper fs does not support tmpfile. overlayfs: failed to resolve './bus': -2 RSP: 0018:ffff88808b52f708 EFLAGS: 00010206 RAX: 00000000001fffff RBX: 0000000020000000 RCX: 0000000000000009 overlayfs: upper fs does not support tmpfile. RDX: 1ffffffff1433958 RSI: ffff88808b6ca670 RDI: ffffffff8a19cac0 RAX: 00000000001fffff RBX: 0000000020000000 RCX: 0000000000000009 RBP: ffff88808b52f870 R08: 0000000000000000 R09: fffffbfff1428ee0 overlayfs: upper fs does not support xattr, falling back to index=off and metacopy=off. R10: fffffbfff1428ee0 R11: 0000000000000001 R12: ffff88808b6196c0 overlayfs: failed to resolve './bus': -2 R13: ffff88808b52f848 R14: ffffffff8a19cab0 R15: ffff88809174e680 RDX: 1ffffffff1433958 RSI: ffff88808b6ca670 RDI: ffffffff8a19cac0 FS: 00007f020385a700(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000 RBP: ffff88808b52f870 R08: 0000000000000000 R09: fffffbfff1428ee0 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 R10: fffffbfff1428ee0 R11: 0000000000000001 R12: ffff88808b6196c0 overlayfs: upper fs does not support xattr, falling back to index=off and metacopy=off. R13: ffff88808b52f848 R14: ffffffff8a19cab0 R15: ffff88809174e680 CR2: 0000000000768060 CR3: 00000000a9111000 CR4: 00000000001406e0 FS: 00007f07a91c6700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 overlayfs: failed to resolve './bus': -2 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033