[syzbot] [jfs?] INFO: task hung in dbAlloc

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: aaa9c3550b60 Add linux-next specific files for 20251022
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=16dd13e2580000
kernel config: https://syzkaller.appspot.com/x/.config?x=c8b911aebadf6410
dashboard link: https://syzkaller.appspot.com/bug?extid=a2bef7ebecf9cb8b880a
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=120ecd2f980000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13506d42580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/44f7af9b7ca1/disk-aaa9c355.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9d09b0a9994d/vmlinux-aaa9c355.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ae729ccb2c5c/bzImage-aaa9c355.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/7922e49d0401/mount_0.gz
fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=16cba3cd980000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a2bef7...@syzkaller.appspotmail.com

INFO: task syz.2.19:6102 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.19 state:D
stack:24744 pid:6102 tgid:6101 ppid:5966 task_flags:0x400140 flags:0x00080003
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5254 [inline]
__schedule+0x17c4/0x4d60 kernel/sched/core.c:6862
__down_read_common kernel/locking/rwsem.c:1261 [inline]
__down_read kernel/locking/rwsem.c:1274 [inline]
down_read_nested+0x9a/0x2f0 kernel/locking/rwsem.c:1663
dbAlloc+0x3a7/0xba0 fs/jfs/jfs_dmap.c:790
diNewExt+0x9af/0x3150 fs/jfs/jfs_imap.c:2261
diAllocExt fs/jfs/jfs_imap.c:1952 [inline]
diAllocAG+0xe86/0x1df0 fs/jfs/jfs_imap.c:1669
diAlloc+0x1d5/0x1680 fs/jfs/jfs_imap.c:1590
ialloc+0x8c/0x8f0 fs/jfs/jfs_inode.c:56
jfs_mkdir+0x193/0xa70 fs/jfs/namei.c:225
vfs_mkdir+0x306/0x510 fs/namei.c:4453
do_mkdirat+0x247/0x590 fs/namei.c:4486
__do_sys_mkdirat fs/namei.c:4503 [inline]
__se_sys_mkdirat fs/namei.c:4501 [inline]
__x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4501
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8089b8efc9
RSP: 002b:00007f808aa1e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f8089de5fa0 RCX: 00007f8089b8efc9
RDX: 0000000000000408 RSI: 0000200000000300 RDI: 0000000000000004
RBP: 00007f8089c11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8089de6038 R14: 00007f8089de5fa0 R15: 00007ffd7baf80e8
</TASK>
INFO: task syz.0.17:6104 blocked for more than 149 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17 state:D stack:24584 pid:6104 tgid:6103 ppid:5962 task_flags:0x400140 flags:0x00080003
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5254 [inline]
__schedule+0x17c4/0x4d60 kernel/sched/core.c:6862
__schedule_loop kernel/sched/core.c:6944 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6959
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7016
rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1086
__down_read_common kernel/locking/rwsem.c:1261 [inline]
__down_read kernel/locking/rwsem.c:1274 [inline]
down_read_nested+0x9a/0x2f0 kernel/locking/rwsem.c:1663
dbAlloc+0x3a7/0xba0 fs/jfs/jfs_dmap.c:790
diNewExt+0x9af/0x3150 fs/jfs/jfs_imap.c:2261
diAllocExt fs/jfs/jfs_imap.c:1952 [inline]
diAllocAG+0xe86/0x1df0 fs/jfs/jfs_imap.c:1669
diAlloc+0x1d5/0x1680 fs/jfs/jfs_imap.c:1590
ialloc+0x8c/0x8f0 fs/jfs/jfs_inode.c:56
jfs_mkdir+0x193/0xa70 fs/jfs/namei.c:225
vfs_mkdir+0x306/0x510 fs/namei.c:4453
do_mkdirat+0x247/0x590 fs/namei.c:4486
__do_sys_mkdirat fs/namei.c:4503 [inline]
__se_sys_mkdirat fs/namei.c:4501 [inline]
__x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4501
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f54be18efc9
RSP: 002b:00007f54bf04c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f54be3e5fa0 RCX: 00007f54be18efc9
RDX: 0000000000000408 RSI: 0000200000000300 RDI: 0000000000000004
RBP: 00007f54be211f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f54be3e6038 R14: 00007f54be3e5fa0 R15: 00007ffc81bd5328
</TASK>
INFO: task syz.3.20:6107 blocked for more than 150 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.20 state:D stack:25064 pid:6107 tgid:6106 ppid:5970 task_flags:0x400140 flags:0x00080003
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5254 [inline]
__schedule+0x17c4/0x4d60 kernel/sched/core.c:6862
__schedule_loop kernel/sched/core.c:6944 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6959
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7016
rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1086
__down_read_common kernel/locking/rwsem.c:1261 [inline]
__down_read kernel/locking/rwsem.c:1274 [inline]
down_read_nested+0x9a/0x2f0 kernel/locking/rwsem.c:1663
dbAlloc+0x3a7/0xba0 fs/jfs/jfs_dmap.c:790
diNewExt+0x9af/0x3150 fs/jfs/jfs_imap.c:2261
diAllocExt fs/jfs/jfs_imap.c:1952 [inline]
diAllocAG+0xe86/0x1df0 fs/jfs/jfs_imap.c:1669


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