loop0: detected capacity change from 0 to 4096 ------------[ cut here ]------------ DEBUG_RWSEMS_WARN_ON(!is_rwsem_reader_owned(sem)): count = 0x0, magic = 0xffff8880446aca38, owner = 0x0, curr 0xffff888000b48000, list not empty WARNING: kernel/locking/rwsem.c:1384 at __up_read+0x6a7/0x930 kernel/locking/rwsem.c:1384, CPU#0: syz.0.0/5314 Modules linked in: CPU: 0 UID: 0 PID: 5314 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:__up_read+0x77f/0x930 kernel/locking/rwsem.c:1384 Code: 8c 49 c7 c2 80 1b 0d 8c 4c 0f 44 d0 48 8b 7c 24 28 48 c7 c6 40 1b 0d 8c 48 8b 54 24 18 4c 89 e9 4d 89 e0 4c 8b 4c 24 08 41 52 <67> 48 0f b9 3a 48 83 c4 08 e8 e3 bb 39 03 4c 8b 3c 24 48 8b 5c 24 RSP: 0018:ffffc9000f36f8d8 EFLAGS: 00010246 RAX: ffffffff8c0d1ba0 RBX: 1ffff110088d5948 RCX: ffff8880446aca38 RDX: 0000000000000000 RSI: ffffffff8c0d1b40 RDI: ffffffff907d6f70 RBP: ffffc9000f36f9c0 R08: 0000000000000000 R09: ffff888000b48000 R10: ffffffff8c0d1ba0 R11: ffffed10088d5949 R12: 0000000000000000 R13: ffff8880446aca38 R14: ffff8880446aca90 R15: ffff8880446aca40 FS: 00007fd74c1b06c0(0000) GS:ffff88808c2cd000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f58dc797000 CR3: 000000001201b000 CR4: 0000000000352ef0 Call Trace: inode_unlock_shared include/linux/fs.h:1049 [inline] lookup_slow+0x5e/0x70 fs/namei.c:1937 walk_component fs/namei.c:2282 [inline] link_path_walk+0xd2a/0x1910 fs/namei.c:2656 path_openat+0x1c9/0x1d60 fs/namei.c:4996 do_file_open+0x23e/0x4a0 fs/namei.c:5029 do_sys_openat2+0x115/0x200 fs/open.c:1417 do_sys_open fs/open.c:1423 [inline] __do_sys_openat fs/open.c:1439 [inline] __se_sys_openat fs/open.c:1434 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1434 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd74b39e159 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd74c1affe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fd74b625fa0 RCX: 00007fd74b39e159 RDX: 0000000000000002 RSI: 0000200000000140 RDI: ffffffffffffff9c RBP: 00007fd74b435024 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000010b R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd74b626038 R14: 00007fd74b625fa0 R15: 00007ffe7662ded8 ---------------- Code disassembly (best guess): 0: 8c 49 c7 mov %cs,-0x39(%rcx) 3: c2 80 1b ret $0x1b80 6: 0d 8c 4c 0f 44 or $0x440f4c8c,%eax b: d0 48 8b rorb $1,-0x75(%rax) e: 7c 24 jl 0x34 10: 28 48 c7 sub %cl,-0x39(%rax) 13: c6 40 1b 0d movb $0xd,0x1b(%rax) 17: 8c 48 8b mov %cs,-0x75(%rax) 1a: 54 push %rsp 1b: 24 18 and $0x18,%al 1d: 4c 89 e9 mov %r13,%rcx 20: 4d 89 e0 mov %r12,%r8 23: 4c 8b 4c 24 08 mov 0x8(%rsp),%r9 28: 41 52 push %r10 * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: 48 83 c4 08 add $0x8,%rsp 33: e8 e3 bb 39 03 call 0x339bc1b 38: 4c 8b 3c 24 mov (%rsp),%r15 3c: 48 rex.W 3d: 8b .byte 0x8b 3e: 5c pop %rsp 3f: 24 .byte 0x24