Hello, syzbot found the following issue on: HEAD commit: d03154e8 Add linux-next specific files for 20210128 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=1088091cd00000 kernel config: https://syzkaller.appspot.com/x/.config?x=6953ffb584722a1 dashboard link: https://syzkaller.appspot.com/bug?extid=d65b0638dd3d123794f2 compiler: gcc (GCC) 10.1.0-syz 20200507 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+d65b0638dd3d123794f2@xxxxxxxxxxxxxxxxxxxxxxxxx general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] CPU: 0 PID: 30787 Comm: syz-executor.3 Not tainted 5.11.0-rc5-next-20210128-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:invalidate_bdev+0x1f/0xd0 fs/block_dev.c:92 Code: ff 66 2e 0f 1f 84 00 00 00 00 00 55 53 48 89 fb e8 16 29 a0 ff 48 8d 7b 28 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 93 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b RSP: 0018:ffffc90017c07848 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc9000f244000 RDX: 0000000000000005 RSI: ffffffff81d2ec3a RDI: 0000000000000028 RBP: ffff888073ecc000 R08: 0000000000000000 R09: ffffffff8b2146c3 R10: fffffbfff16428d8 R11: 0000000000000000 R12: ffff888076c38cc0 R13: 0000000000000001 R14: 0000000000000001 R15: ffff888028720000 FS: 00007fe9ef641700(0000) GS:ffff8880b9e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb745112db8 CR3: 000000008b834000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: open_ctree+0xab3/0x4060 fs/btrfs/disk-io.c:3086 btrfs_fill_super fs/btrfs/super.c:1356 [inline] btrfs_mount_root.cold+0x14/0x165 fs/btrfs/super.c:1723 legacy_get_tree+0x105/0x220 fs/fs_context.c:592 vfs_get_tree+0x89/0x2f0 fs/super.c:1497 fc_mount fs/namespace.c:993 [inline] vfs_kern_mount.part.0+0xd3/0x170 fs/namespace.c:1023 vfs_kern_mount+0x3c/0x60 fs/namespace.c:1010 btrfs_mount+0x234/0xa20 fs/btrfs/super.c:1783 legacy_get_tree+0x105/0x220 fs/fs_context.c:592 vfs_get_tree+0x89/0x2f0 fs/super.c:1497 do_new_mount fs/namespace.c:2903 [inline] path_mount+0x132a/0x1f90 fs/namespace.c:3233 do_mount fs/namespace.c:3246 [inline] __do_sys_mount fs/namespace.c:3454 [inline] __se_sys_mount fs/namespace.c:3431 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3431 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x460c6a Code: b8 a6 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 ad 89 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 8a 89 fb ff c3 66 0f 1f 84 00 00 00 00 00 RSP: 002b:00007fe9ef640a78 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fe9ef640b10 RCX: 0000000000460c6a RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007fe9ef640ad0 RBP: 00007fe9ef640ad0 R08: 00007fe9ef640b10 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000020000000 R13: 0000000020000100 R14: 0000000020000200 R15: 0000000020003d00 Modules linked in: ---[ end trace 44edaf4ec7942bd8 ]--- RIP: 0010:invalidate_bdev+0x1f/0xd0 fs/block_dev.c:92 Code: ff 66 2e 0f 1f 84 00 00 00 00 00 55 53 48 89 fb e8 16 29 a0 ff 48 8d 7b 28 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 93 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b RSP: 0018:ffffc90017c07848 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc9000f244000 RDX: 0000000000000005 RSI: ffffffff81d2ec3a RDI: 0000000000000028 RBP: ffff888073ecc000 R08: 0000000000000000 R09: ffffffff8b2146c3 R10: fffffbfff16428d8 R11: 0000000000000000 R12: ffff888076c38cc0 R13: 0000000000000001 R14: 0000000000000001 R15: ffff888028720000 FS: 00007fe9ef641700(0000) GS:ffff8880b9f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffdfaea9138 CR3: 000000008b834000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot.