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kernel BUG at fs/ocfs2/refcounttree.c:2890!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 6143 Comm: syz.0.15 Not tainted 6.16.0-rc3-syzkaller-g78f4e737a53e #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:ocfs2_clear_cow_buffer+0x79/0x80 fs/ocfs2/refcounttree.c:2890
Code: 02 75 21 e8 79 92 1d fe 48 89 df be 08 00 00 00 e8 dc 17 81 fe 3e 80 23 ef 31 c0 5b 41 5e c3 cc cc cc cc cc e8 58 92 1d fe 90 <0f> 0b 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000d54f058 EFLAGS: 00010293
RAX: ffffffff83a2bac8 RBX: ffff8880447e51d0 RCX: ffff888035e58000
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000000
RBP: 0000000000000001 R08: ffff8880447e51d7 R09: 1ffff110088fca3a
R10: dffffc0000000000 R11: ffffed10088fca3b R12: ffff8880447e51d0
R13: ffff8880447e50e8 R14: 0000000000000002 R15: 0000000000001000
FS:  00007f3388b586c0(0000) GS:ffff88808d251000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2b08f79fe8 CR3: 0000000046911000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 walk_page_buffers+0x91/0x1e0 fs/ocfs2/aops.c:419
 ocfs2_duplicate_clusters_by_page+0x720/0xc90 fs/ocfs2/refcounttree.c:2969
 ocfs2_replace_clusters fs/ocfs2/refcounttree.c:3120 [inline]
 ocfs2_make_clusters_writable fs/ocfs2/refcounttree.c:3252 [inline]
 ocfs2_replace_cow+0xac7/0x1b90 fs/ocfs2/refcounttree.c:3346
 ocfs2_refcount_cow_hunk fs/ocfs2/refcounttree.c:3424 [inline]
 ocfs2_refcount_cow+0x779/0xc90 fs/ocfs2/refcounttree.c:3467
 ocfs2_prepare_inode_for_write fs/ocfs2/file.c:2340 [inline]
 ocfs2_file_write_iter+0xe28/0x1d10 fs/ocfs2/file.c:2451
 do_iter_readv_writev+0x56b/0x7f0 fs/read_write.c:-1
 vfs_writev+0x31a/0x960 fs/read_write.c:1057
 do_pwritev fs/read_write.c:1153 [inline]
 __do_sys_pwritev2 fs/read_write.c:1211 [inline]
 __se_sys_pwritev2+0x179/0x290 fs/read_write.c:1202
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3387d7e719
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3388b58038 EFLAGS: 00000246 ORIG_RAX: 0000000000000148
RAX: ffffffffffffffda RBX: 00007f3387f35f80 RCX: 00007f3387d7e719
RDX: 0000000000000001 RSI: 0000000020000240 RDI: 0000000000000005
RBP: 00007f3387df132e R08: 0000000000000000 R09: 0000000000000003
R10: 0000000000007800 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f3387f35f80 R15: 00007ffdde6b54c8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ocfs2_clear_cow_buffer+0x79/0x80 fs/ocfs2/refcounttree.c:2890
Code: 02 75 21 e8 79 92 1d fe 48 89 df be 08 00 00 00 e8 dc 17 81 fe 3e 80 23 ef 31 c0 5b 41 5e c3 cc cc cc cc cc e8 58 92 1d fe 90 <0f> 0b 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc9000d54f058 EFLAGS: 00010293
RAX: ffffffff83a2bac8 RBX: ffff8880447e51d0 RCX: ffff888035e58000
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000000
RBP: 0000000000000001 R08: ffff8880447e51d7 R09: 1ffff110088fca3a
R10: dffffc0000000000 R11: ffffed10088fca3b R12: ffff8880447e51d0
R13: ffff8880447e50e8 R14: 0000000000000002 R15: 0000000000001000
FS:  00007f3388b586c0(0000) GS:ffff88808d251000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000560dde5b9660 CR3: 0000000046911000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400