loop8: detected capacity change from 0 to 32768
BUG at fs/jfs/jfs_dmap.c:2983 assert(n < 4)
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kernel BUG at fs/jfs/jfs_dmap.c:2983!
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 0 UID: 0 PID: 13035 Comm: syz.8.1456 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:dbFindLeaf+0x51d/0x520 fs/jfs/jfs_dmap.c:2983
Code: e9 4c ff ff ff e8 83 bb 78 fe 48 c7 c7 e0 4f a5 8b 48 c7 c6 20 4d a5 8b ba a7 0b 00 00 48 c7 c1 c0 5a a5 8b e8 b4 b1 de fd 90 <0f> 0b 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57
RSP: 0018:ffffc9000bd57a78 EFLAGS: 00010246
RAX: 000000000000002b RBX: 0000000000000000 RCX: c325da3cc0aeae00
RDX: ffffc900139f5000 RSI: 0000000000002877 RDI: 0000000000002878
RBP: 0000000000000003 R08: ffffffff8f820377 R09: 1ffffffff1f0406e
R10: dffffc0000000000 R11: fffffbfff1f0406f R12: 000000000000000a
R13: 0000000000000008 R14: 0000000000000005 R15: 0000000000000155
FS:  00007f1de15cc6c0(0000) GS:ffff888125e37000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efe19db7198 CR3: 0000000057064000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000001 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 dbAllocDmapLev+0x60/0x3c0 fs/jfs/jfs_dmap.c:1969
 dbAllocCtl+0x14a/0x9c0 fs/jfs/jfs_dmap.c:1825
 dbAllocAG+0xc2b/0xff0 fs/jfs/jfs_dmap.c:1472
 dbDiscardAG+0x2df/0x900 fs/jfs/jfs_dmap.c:1608
 jfs_ioc_trim+0x429/0x690 fs/jfs/jfs_discard.c:106
 jfs_ioctl+0x2b5/0x3d0 fs/jfs/ioctl.c:131
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1de078f749
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:00007f1de15cc038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f1de09e5fa0 RCX: 00007f1de078f749
RDX: 0000200000000080 RSI: 00000000c0185879 RDI: 0000000000000007
RBP: 00007f1de0813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1de09e6038 R14: 00007f1de09e5fa0 R15: 00007ffe40b1ef18
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:dbFindLeaf+0x51d/0x520 fs/jfs/jfs_dmap.c:2983
Code: e9 4c ff ff ff e8 83 bb 78 fe 48 c7 c7 e0 4f a5 8b 48 c7 c6 20 4d a5 8b ba a7 0b 00 00 48 c7 c1 c0 5a a5 8b e8 b4 b1 de fd 90 <0f> 0b 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57
RSP: 0018:ffffc9000bd57a78 EFLAGS: 00010246
RAX: 000000000000002b RBX: 0000000000000000 RCX: c325da3cc0aeae00
RDX: ffffc900139f5000 RSI: 0000000000002877 RDI: 0000000000002878
RBP: 0000000000000003 R08: ffffffff8f820377 R09: 1ffffffff1f0406e
R10: dffffc0000000000 R11: fffffbfff1f0406f R12: 000000000000000a
R13: 0000000000000008 R14: 0000000000000005 R15: 0000000000000155
FS:  00007f1de15cc6c0(0000) GS:ffff888125f37000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f09259b6ad8 CR3: 0000000057064000 CR4: 00000000003526f0