[v5.15] INFO: task hung in perf_uprobe_init

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 68efe5a6c16a Linux 5.15.197
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=16d18f92580000
kernel config: https://syzkaller.appspot.com/x/.config?x=7e6ed99963d6ee1d
dashboard link: https://syzkaller.appspot.com/bug?extid=33a4b4aea70560a66219
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/998e4247f9d0/disk-68efe5a6.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4ef4066c91ec/vmlinux-68efe5a6.xz
kernel image: https://storage.googleapis.com/syzbot-assets/922e7b640c48/bzImage-68efe5a6.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+33a4b4...@syzkaller.appspotmail.com

INFO: task syz.9.5273:24414 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.5273 state:D stack:29088 pid:24414 ppid: 24336 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
__mutex_lock_common+0xc71/0x2390 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
perf_uprobe_init+0x11f/0x190 kernel/trace/trace_event_perf.c:335
perf_uprobe_event_init+0xe2/0x170 kernel/events/core.c:10253
perf_try_init_event+0x12b/0x3d0 kernel/events/core.c:11601
perf_init_event kernel/events/core.c:11665 [inline]
perf_event_alloc+0xfcf/0x2240 kernel/events/core.c:11957
__do_sys_perf_event_open kernel/events/core.c:12495 [inline]
__se_sys_perf_event_open+0x6c5/0x1b80 kernel/events/core.c:12387
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f08e4659749
RSP: 002b:00007f08e289f038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 00007f08e48b0090 RCX: 00007f08e4659749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000001080
RBP: 00007f08e46ddf91 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f08e48b0128 R14: 00007f08e48b0090 R15: 00007ffe67814c08
</TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c11c720 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
1 lock held by klogd/3551:
2 locks held by getty/3947:
#0: ffff88802c4ef098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
1 lock held by syz-executor/4173:
#0: ffff88807d886a28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#0: ffff88807d886a28 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x15d/0x2b0 mm/util.c:549
2 locks held by syz-executor/16814:
#0: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
#1: ffff88802c019d28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#1: ffff88802c019d28 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:504 [inline]
#1: ffff88802c019d28 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1466 [inline]
#1: ffff88802c019d28 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x238/0x1380 kernel/fork.c:1518
2 locks held by syz-executor/20050:
#0: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
#1: ffff88807e3c7828 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#1: ffff88807e3c7828 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:504 [inline]
#1: ffff88807e3c7828 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1466 [inline]
#1: ffff88807e3c7828 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x238/0x1380 kernel/fork.c:1518
2 locks held by syz-executor/20095:
#0: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: dup_mmap kernel/fork.c:503 [inline]
#0: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1466 [inline]
#0: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm+0x21f/0x1380 kernel/fork.c:1518
#1: ffff8880526e9d28 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#1: ffff8880526e9d28 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:504 [inline]
#1: ffff8880526e9d28 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1466 [inline]
#1: ffff8880526e9d28 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x238/0x1380 kernel/fork.c:1518
4 locks held by syz.9.5273/24413:
#0: ffffffff96101918 (&pmus_srcu){....}-{0:0}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:313
#1: ffffffff8c169e28 (event_mutex){+.+.}-{3:3}, at: perf_uprobe_init+0x11f/0x190 kernel/trace/trace_event_perf.c:335
#2: ffff88805b248090 (&uprobe->register_rwsem){+.+.}-{3:3}, at: __uprobe_register+0x450/0x750 kernel/events/uprobes.c:1178
#3: ffffffff8c1a68b0 (dup_mmap_sem){++++}-{0:0}, at: register_for_each_vma+0x2f/0xbb0 kernel/events/uprobes.c:1041
2 locks held by syz.9.5273/24414:
#0: ffffffff96101918 (&pmus_srcu){....}-{0:0}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:313
#1: ffffffff8c169e28 (event_mutex){+.+.}-{3:3}, at: perf_uprobe_init+0x11f/0x190 kernel/trace/trace_event_perf.c:335

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
<TASK>
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe0f/0xe50 kernel/hung_task.c:369
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 0 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:729


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