INFO: task syz.0.111:6287 blocked for more than 143 seconds.
Not tainted 6.15.0-rc7-next-20250523-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.111 state:D
stack:26184 pid:6287 tgid:6286 ppid:5838 task_flags:0x400140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
netfs_wait_for_request+0x1f0/0x600 fs/netfs/misc.c:450
netfs_unbuffered_write_iter_locked+0x52a/0x910 fs/netfs/direct_write.c:110
netfs_unbuffered_write_iter+0x4c4/0x660 fs/netfs/direct_write.c:193
do_iter_readv_writev+0x56b/0x7f0 fs/read_write.c:-1
vfs_writev+0x306/0x9a0 fs/read_write.c:1057
do_writev+0x14d/0x2d0 fs/read_write.c:1103
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: 0033:0x7f5bdf78e969
RSP: 002b:00007f5be05e0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007f5bdf9b5fa0 RCX: 00007f5bdf78e969
RDX: 0000000000000002 RSI: 0000200000000000 RDI: 0000000000000006
RBP: 00007f5bdf810ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f5bdf9b5fa0 R15: 00007fff5137ebd8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13f140 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13f140 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13f140 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by getty/5595:
#0: ffff888030a2b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/5834:
#0: ffffffff8e144c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#0: ffffffff8e144c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998
3 locks held by syz.0.111/6287:
#0: ffff8880342ba478 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320 fs/file.c:1213
#1: ffff888028cdc428 (sb_writers#17){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3092 [inline]
#1: ffff888028cdc428 (sb_writers#17){.+.+}-{0:0}, at: vfs_writev+0x274/0x9a0 fs/read_write.c:1055
#2: ffff8880571807b8 (&sb->s_type->i_mutex_key#21){++++}-{4:4}, at: netfs_start_io_direct+0x1ef/0x230 fs/netfs/locking.c:188
1 lock held by syz.1.861/8529:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc7-next-20250523-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:470
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 7262 Comm: kworker/u8:14 Not tainted 6.15.0-rc7-next-20250523-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: krdsd rds_connect_worker
RIP: 0010:check_kcov_mode kernel/kcov.c:194 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x37/0x70 kernel/kcov.c:217
Code: 08 a0 9c 92 65 8b 15 e8 5c dc 10 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 3c 16 00 00 00 74 2c 8b 91 18 16 00 00 <83> fa 02 75 21 48 8b 91 20 16 00 00 48 8b 32 48 8d 7e 01 8b 89 1c
RSP: 0018:ffffc90003e7f858 EFLAGS: 00000246
RAX: ffffffff89432700 RBX: ffff88803522eae8 RCX: ffff8880791e9e00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffff88803522e89f R09: 1ffff11006a45d13
R10: dffffc0000000000 R11: ffffed1006a45d14 R12: 1ffff11006a45cef
R13: 0000000000000000 R14: ffff88803522e600 R15: ffff88803522e778
FS: 0000000000000000(0000) GS:ffff888125c56000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbcf7980178 CR3: 000000000df38000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__sk_destruct+0x130/0x660 net/core/sock.c:2310
inet_release+0x184/0x210 net/ipv4/af_inet.c:435
__sock_release net/socket.c:647 [inline]
sock_release+0x82/0x150 net/socket.c:675
rds_tcp_conn_path_connect+0x37d/0x680 net/rds/tcp_connect.c:191
rds_connect_worker+0x1d5/0x290 net/rds/threads.c:176
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x711/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245