[syzbot] possible deadlock in vm_mmap_pgoff

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 7af08140 Revert "gcov: clang: fix clang-11+ build"
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17d57dfed00000
kernel config: https://syzkaller.appspot.com/x/.config?x=76c0382ceab56d34
dashboard link: https://syzkaller.appspot.com/bug?extid=f619f7c0a2a5f87694e6

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f619f7...@syzkaller.appspotmail.com

======================================================
WARNING: possible circular locking dependency detected
5.12.0-rc8-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.1/16055 is trying to acquire lock:
ffffffff8bfe2bc8 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x23/0xf0 kernel/trace/trace_event_perf.c:241

but task is already holding lock:
ffff88801b887258 (&mm->mmap_lock#2){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
ffff88801b887258 (&mm->mmap_lock#2){++++}-{3:3}, at: vm_mmap_pgoff+0x15c/0x290 mm/util.c:517

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&mm->mmap_lock#2){++++}-{3:3}:
down_write_killable+0x95/0x170 kernel/locking/rwsem.c:1417
mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
dup_mmap kernel/fork.c:480 [inline]
dup_mm+0x12e/0x1380 kernel/fork.c:1368
copy_mm kernel/fork.c:1424 [inline]
copy_process+0x2bc8/0x71a0 kernel/fork.c:2113
kernel_clone+0xe7/0xab0 kernel/fork.c:2500
__do_sys_clone+0xc8/0x110 kernel/fork.c:2617
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae

-> #2 (dup_mmap_sem){++++}-{0:0}:
percpu_down_write+0x95/0x440 kernel/locking/percpu-rwsem.c:217
register_for_each_vma+0x2c/0xc10 kernel/events/uprobes.c:1040
__uprobe_register+0x5c2/0x850 kernel/events/uprobes.c:1181
trace_uprobe_enable kernel/trace/trace_uprobe.c:1065 [inline]
probe_event_enable+0x357/0xa00 kernel/trace/trace_uprobe.c:1134
trace_uprobe_register+0x443/0x880 kernel/trace/trace_uprobe.c:1461
perf_trace_event_reg kernel/trace/trace_event_perf.c:129 [inline]
perf_trace_event_init+0x549/0xa20 kernel/trace/trace_event_perf.c:204
perf_uprobe_init+0x16f/0x210 kernel/trace/trace_event_perf.c:336
perf_uprobe_event_init+0xff/0x1c0 kernel/events/core.c:9754
perf_try_init_event+0x12a/0x560 kernel/events/core.c:11071
perf_init_event kernel/events/core.c:11123 [inline]
perf_event_alloc.part.0+0xe3b/0x3960 kernel/events/core.c:11403
perf_event_alloc kernel/events/core.c:11785 [inline]
__do_sys_perf_event_open+0x647/0x2e60 kernel/events/core.c:11883
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae

-> #1 (&uprobe->register_rwsem){+.+.}-{3:3}:
down_write+0x92/0x150 kernel/locking/rwsem.c:1406
__uprobe_register+0x531/0x850 kernel/events/uprobes.c:1177
trace_uprobe_enable kernel/trace/trace_uprobe.c:1065 [inline]
probe_event_enable+0x357/0xa00 kernel/trace/trace_uprobe.c:1134
trace_uprobe_register+0x443/0x880 kernel/trace/trace_uprobe.c:1461
perf_trace_event_reg kernel/trace/trace_event_perf.c:129 [inline]
perf_trace_event_init+0x549/0xa20 kernel/trace/trace_event_perf.c:204
perf_uprobe_init+0x16f/0x210 kernel/trace/trace_event_perf.c:336
perf_uprobe_event_init+0xff/0x1c0 kernel/events/core.c:9754
perf_try_init_event+0x12a/0x560 kernel/events/core.c:11071
perf_init_event kernel/events/core.c:11123 [inline]
perf_event_alloc.part.0+0xe3b/0x3960 kernel/events/core.c:11403
perf_event_alloc kernel/events/core.c:11785 [inline]
__do_sys_perf_event_open+0x647/0x2e60 kernel/events/core.c:11883
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae

-> #0 (event_mutex){+.+.}-{3:3}:
check_prev_add kernel/locking/lockdep.c:2937 [inline]
check_prevs_add kernel/locking/lockdep.c:3060 [inline]
validate_chain kernel/locking/lockdep.c:3675 [inline]
__lock_acquire+0x2b14/0x54c0 kernel/locking/lockdep.c:4901
lock_acquire kernel/locking/lockdep.c:5511 [inline]
lock_acquire+0x1ab/0x740 kernel/locking/lockdep.c:5476
__mutex_lock_common kernel/locking/mutex.c:949 [inline]
__mutex_lock+0x139/0x1120 kernel/locking/mutex.c:1096
perf_trace_destroy+0x23/0xf0 kernel/trace/trace_event_perf.c:241
_free_event+0x2ee/0x1380 kernel/events/core.c:4863
put_event kernel/events/core.c:4957 [inline]
perf_mmap_close+0x572/0xe10 kernel/events/core.c:6002
remove_vma+0xae/0x170 mm/mmap.c:180
remove_vma_list mm/mmap.c:2653 [inline]
__do_munmap+0x74f/0x11a0 mm/mmap.c:2909
do_munmap mm/mmap.c:2917 [inline]
munmap_vma_range mm/mmap.c:598 [inline]
mmap_region+0x85a/0x1730 mm/mmap.c:1750
do_mmap+0xcff/0x11d0 mm/mmap.c:1581
vm_mmap_pgoff+0x1b7/0x290 mm/util.c:519
ksys_mmap_pgoff+0x49c/0x620 mm/mmap.c:1632
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae

other info that might help us debug this:

Chain exists of:
event_mutex --> dup_mmap_sem --> &mm->mmap_lock#2

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&mm->mmap_lock#2);
lock(dup_mmap_sem);
lock(&mm->mmap_lock#2);
lock(event_mutex);

*** DEADLOCK ***

1 lock held by syz-executor.1/16055:
#0: ffff88801b887258 (&mm->mmap_lock#2){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#0: ffff88801b887258 (&mm->mmap_lock#2){++++}-{3:3}, at: vm_mmap_pgoff+0x15c/0x290 mm/util.c:517

stack backtrace:
CPU: 2 PID: 16055 Comm: syz-executor.1 Not tainted 5.12.0-rc8-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Call Trace:
__dump_stack lib/dump_stack.c:79 [inline]
dump_stack+0x141/0x1d7 lib/dump_stack.c:120
check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2128
check_prev_add kernel/locking/lockdep.c:2937 [inline]
check_prevs_add kernel/locking/lockdep.c:3060 [inline]
validate_chain kernel/locking/lockdep.c:3675 [inline]
__lock_acquire+0x2b14/0x54c0 kernel/locking/lockdep.c:4901
lock_acquire kernel/locking/lockdep.c:5511 [inline]
lock_acquire+0x1ab/0x740 kernel/locking/lockdep.c:5476
__mutex_lock_common kernel/locking/mutex.c:949 [inline]
__mutex_lock+0x139/0x1120 kernel/locking/mutex.c:1096
perf_trace_destroy+0x23/0xf0 kernel/trace/trace_event_perf.c:241
_free_event+0x2ee/0x1380 kernel/events/core.c:4863
put_event kernel/events/core.c:4957 [inline]
perf_mmap_close+0x572/0xe10 kernel/events/core.c:6002
remove_vma+0xae/0x170 mm/mmap.c:180
remove_vma_list mm/mmap.c:2653 [inline]
__do_munmap+0x74f/0x11a0 mm/mmap.c:2909
do_munmap mm/mmap.c:2917 [inline]
munmap_vma_range mm/mmap.c:598 [inline]
mmap_region+0x85a/0x1730 mm/mmap.c:1750
do_mmap+0xcff/0x11d0 mm/mmap.c:1581
vm_mmap_pgoff+0x1b7/0x290 mm/util.c:519
ksys_mmap_pgoff+0x49c/0x620 mm/mmap.c:1632
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x466459
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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007eff7f246188 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459
RDX: 0000000000000000 RSI: 0000000000003000 RDI: 0000000020ffc000
RBP: 00000000004bf9fb R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000011 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007fff0b32a74f R14: 00007eff7f246300 R15: 0000000000022000


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

[Hillf Danton]

On Tue, 27 Apr 2021 08:18:27

Break the lock chain by asking kworker to destroy perf event.
Thoughts other than workqueue are appreciated.

+++ x/kernel/trace/trace_event_perf.c
@@ -236,14 +236,22 @@ int perf_trace_init(struct perf_event *p
return ret;
}

-void perf_trace_destroy(struct perf_event *p_event)
+static void perf_trace_destroy_work_fn(struct work_struct *w)
{
+ struct perf_event *p_event = container_of(w, struct perf_event,
+ destroy_work);
mutex_lock(&event_mutex);
perf_trace_event_close(p_event);
perf_trace_event_unreg(p_event);
mutex_unlock(&event_mutex);
}

+void perf_trace_destroy(struct perf_event *p_event)
+{
+ INIT_WORK(&p_event->destroy_work, perf_trace_destroy_work_fn);
+ queue_work(system_unbound_wq, &p_event->destroy_work);
+}
+
#ifdef CONFIG_KPROBE_EVENTS
int perf_kprobe_init(struct perf_event *p_event, bool is_retprobe)
{

[Steven Rostedt]

I think this could cause a problem with the delay.

This is called from event->destroy()


if (event->destroy)
event->destroy(event);
module_put(pmu->module);

What if this event is in that module, and we just unloaded it?

Then the workqueue would try to modify the module text that no longer
exists. Right?

I Cc'd some people that understand this code better.

-- Steve

[Hillf Danton]

On Wed, 28 Apr 2021 09:30:18 Steven Rostedt wrote:

Good question. Thanks for taking a look.

>
>Then the workqueue would try to modify the module text that no longer
>exists. Right?

Yes. Another problem rises in regard of the rcu callback of perf event - both
can be addressed by asking kworker to some more work in addition to event_mutex.

+++ x/kernel/events/core.c
@@ -4918,6 +4918,33 @@ static bool exclusive_event_installable(
static void perf_addr_filters_splice(struct perf_event *event,
struct list_head *head);

+static void perf_event_destroy_work_fn(struct work_struct *w)
+{
+ struct perf_event *event = container_of(w, struct perf_event,
+ destroy_work);
+ if (event->destroy)
+ event->destroy(event);
+
+ /*
+ * Must be after ->destroy(), due to uprobe_perf_close() using
+ * hw.target.
+ */
+ if (event->hw.target)
+ put_task_struct(event->hw.target);
+
+ /*
+ * perf_event_free_task() relies on put_ctx() being 'last',
+ * in particular all task references must be cleaned up.
+ */
+ if (event->ctx)
+ put_ctx(event->ctx);
+
+ exclusive_event_destroy(event);
+ module_put(event->pmu->module);
+
+ call_rcu(&event->rcu_head, free_event_rcu);
+}
+
static void _free_event(struct perf_event *event)
{
irq_work_sync(&event->pending);
@@ -4950,27 +4977,22 @@ static void _free_event(struct perf_even
perf_addr_filters_splice(event, NULL);
kfree(event->addr_filter_ranges);

- if (event->destroy)
- event->destroy(event);
-
/*
- * Must be after ->destroy(), due to uprobe_perf_close() using
- * hw.target.
- */
- if (event->hw.target)
- put_task_struct(event->hw.target);
+ defer destroy to workqueue in bid to avoid

- /*
- * perf_event_free_task() relies on put_ctx() being 'last', in particular
- * all task references must be cleaned up.
- */
- if (event->ctx)
- put_ctx(event->ctx);
-
- exclusive_event_destroy(event);
- module_put(event->pmu->module);
-
- call_rcu(&event->rcu_head, free_event_rcu);
+ CPU0 CPU1
+ ---- ----
+ lock(&mm->mmap_lock#2);
+ lock(dup_mmap_sem);
+ lock(&mm->mmap_lock#2);
+ lock(event_mutex);
+
+ *** DEADLOCK ***
+
+ take a look at perf_trace_destroy() for event_mutex
+ */
+ INIT_WORK(&event->destroy_work, perf_event_destroy_work_fn);
+ queue_work(system_unbound_wq, &event->destroy_work);
}

/*

[Peter Zijlstra]

On Wed, Apr 28, 2021 at 09:30:18AM -0400, Steven Rostedt wrote:

> > Break the lock chain by asking kworker to destroy perf event.
> > Thoughts other than workqueue are appreciated.
>
> I think this could cause a problem with the delay.
>
> This is called from event->destroy()
>
>
> if (event->destroy)
> event->destroy(event);
> module_put(pmu->module);

The uprobe and tracepoint pmus will never be a module.

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 9bead1b58c4c Merge tag 'array-bounds-fixes-5.14-rc3' of gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=155a1f5c300000
kernel config: https://syzkaller.appspot.com/x/.config?x=5dc0e3202ae2f574
dashboard link: https://syzkaller.appspot.com/bug?extid=f619f7c0a2a5f87694e6
compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.1
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14e2e196300000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11cc4846300000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f619f7...@syzkaller.appspotmail.com

======================================================
WARNING: possible circular locking dependency detected

5.14.0-rc2-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor238/8449 is trying to acquire lock:
ffffffff8c7658e8 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x27/0xb0 kernel/trace/trace_event_perf.c:241

but task is already holding lock:

ffff888033788f28 (&mm->mmap_lock#2){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
ffff888033788f28 (&mm->mmap_lock#2){++++}-{3:3}, at: vm_mmap_pgoff+0x14d/0x2b0 mm/util.c:517

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&mm->mmap_lock#2){++++}-{3:3}:

lock_acquire+0x182/0x4a0 kernel/locking/lockdep.c:5625
down_write_killable+0xaa/0x1b0 kernel/locking/rwsem.c:1417
mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
dup_mmap+0xde/0xed0 kernel/fork.c:484
dup_mm+0x8c/0x310 kernel/fork.c:1379
copy_mm kernel/fork.c:1431 [inline]
copy_process+0x22e8/0x5b00 kernel/fork.c:2119
kernel_clone+0x21a/0x7d0 kernel/fork.c:2509
__do_sys_clone kernel/fork.c:2626 [inline]
__se_sys_clone kernel/fork.c:2610 [inline]
__x64_sys_clone+0x236/0x2b0 kernel/fork.c:2610
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80

entry_SYSCALL_64_after_hwframe+0x44/0xae

-> #2 (dup_mmap_sem){++++}-{0:0}:

lock_acquire+0x182/0x4a0 kernel/locking/lockdep.c:5625
percpu_down_write+0x52/0x2f0 kernel/locking/percpu-rwsem.c:217
register_for_each_vma+0x32/0xc20 kernel/events/uprobes.c:1041
__uprobe_register+0x5d4/0x860 kernel/events/uprobes.c:1182
trace_uprobe_enable kernel/trace/trace_uprobe.c:1065 [inline]
probe_event_enable+0x399/0xbd0 kernel/trace/trace_uprobe.c:1134
perf_trace_event_reg kernel/trace/trace_event_perf.c:129 [inline]
perf_trace_event_init+0x49b/0x950 kernel/trace/trace_event_perf.c:204
perf_uprobe_init+0x138/0x1a0 kernel/trace/trace_event_perf.c:336
perf_uprobe_event_init+0xfe/0x180 kernel/events/core.c:9875
perf_try_init_event+0x13e/0x3d0 kernel/events/core.c:11192
perf_init_event kernel/events/core.c:11256 [inline]
perf_event_alloc+0x1155/0x2c10 kernel/events/core.c:11547
__do_sys_perf_event_open kernel/events/core.c:12037 [inline]
__se_sys_perf_event_open+0x7a6/0x4020 kernel/events/core.c:11929
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80

entry_SYSCALL_64_after_hwframe+0x44/0xae

-> #1 (&uprobe->register_rwsem){+.+.}-{3:3}:

lock_acquire+0x182/0x4a0 kernel/locking/lockdep.c:5625
down_write+0x97/0x170 kernel/locking/rwsem.c:1406
__uprobe_register+0x4fd/0x860 kernel/events/uprobes.c:1178
trace_uprobe_enable kernel/trace/trace_uprobe.c:1065 [inline]
probe_event_enable+0x399/0xbd0 kernel/trace/trace_uprobe.c:1134
perf_trace_event_reg kernel/trace/trace_event_perf.c:129 [inline]
perf_trace_event_init+0x49b/0x950 kernel/trace/trace_event_perf.c:204
perf_uprobe_init+0x138/0x1a0 kernel/trace/trace_event_perf.c:336
perf_uprobe_event_init+0xfe/0x180 kernel/events/core.c:9875
perf_try_init_event+0x13e/0x3d0 kernel/events/core.c:11192
perf_init_event kernel/events/core.c:11256 [inline]
perf_event_alloc+0x1155/0x2c10 kernel/events/core.c:11547
__do_sys_perf_event_open kernel/events/core.c:12037 [inline]
__se_sys_perf_event_open+0x7a6/0x4020 kernel/events/core.c:11929
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80

entry_SYSCALL_64_after_hwframe+0x44/0xae

-> #0 (event_mutex){+.+.}-{3:3}:

check_prev_add kernel/locking/lockdep.c:3051 [inline]
check_prevs_add+0x4f9/0x5b30 kernel/locking/lockdep.c:3174
validate_chain kernel/locking/lockdep.c:3789 [inline]
__lock_acquire+0x4476/0x6100 kernel/locking/lockdep.c:5015
lock_acquire+0x182/0x4a0 kernel/locking/lockdep.c:5625
__mutex_lock_common+0x1ad/0x3770 kernel/locking/mutex.c:959
__mutex_lock kernel/locking/mutex.c:1104 [inline]
mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:1119
perf_trace_destroy+0x27/0xb0 kernel/trace/trace_event_perf.c:241
_free_event+0xd4d/0x12f0 kernel/events/core.c:4959
put_event kernel/events/core.c:5053 [inline]
perf_mmap_close+0x8ed/0xdf0 kernel/events/core.c:6098
remove_vma mm/mmap.c:186 [inline]
remove_vma_list mm/mmap.c:2656 [inline]
__do_munmap+0x1b95/0x2050 mm/mmap.c:2914
do_munmap mm/mmap.c:2922 [inline]
munmap_vma_range mm/mmap.c:604 [inline]
mmap_region+0x90c/0x1df0 mm/mmap.c:1753
do_mmap+0x89e/0x10c0 mm/mmap.c:1584
vm_mmap_pgoff+0x19e/0x2b0 mm/util.c:519
ksys_mmap_pgoff+0x504/0x7b0 mm/mmap.c:1635
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80

entry_SYSCALL_64_after_hwframe+0x44/0xae

other info that might help us debug this:

Chain exists of:
event_mutex --> dup_mmap_sem --> &mm->mmap_lock#2

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&mm->mmap_lock#2);
lock(dup_mmap_sem);
lock(&mm->mmap_lock#2);
lock(event_mutex);

*** DEADLOCK ***

1 lock held by syz-executor238/8449:
#0: ffff888033788f28 (&mm->mmap_lock#2){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#0: ffff888033788f28 (&mm->mmap_lock#2){++++}-{3:3}, at: vm_mmap_pgoff+0x14d/0x2b0 mm/util.c:517

stack backtrace:
CPU: 1 PID: 8449 Comm: syz-executor238 Not tainted 5.14.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1ae/0x29f lib/dump_stack.c:105
print_circular_bug+0xb17/0xdc0 kernel/locking/lockdep.c:2009
check_noncircular+0x2cc/0x390 kernel/locking/lockdep.c:2131
check_prev_add kernel/locking/lockdep.c:3051 [inline]
check_prevs_add+0x4f9/0x5b30 kernel/locking/lockdep.c:3174
validate_chain kernel/locking/lockdep.c:3789 [inline]
__lock_acquire+0x4476/0x6100 kernel/locking/lockdep.c:5015
lock_acquire+0x182/0x4a0 kernel/locking/lockdep.c:5625
__mutex_lock_common+0x1ad/0x3770 kernel/locking/mutex.c:959
__mutex_lock kernel/locking/mutex.c:1104 [inline]
mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:1119
perf_trace_destroy+0x27/0xb0 kernel/trace/trace_event_perf.c:241
_free_event+0xd4d/0x12f0 kernel/events/core.c:4959
put_event kernel/events/core.c:5053 [inline]
perf_mmap_close+0x8ed/0xdf0 kernel/events/core.c:6098
remove_vma mm/mmap.c:186 [inline]
remove_vma_list mm/mmap.c:2656 [inline]
__do_munmap+0x1b95/0x2050 mm/mmap.c:2914
do_munmap mm/mmap.c:2922 [inline]
munmap_vma_range mm/mmap.c:604 [inline]
mmap_region+0x90c/0x1df0 mm/mmap.c:1753
do_mmap+0x89e/0x10c0 mm/mmap.c:1584
vm_mmap_pgoff+0x19e/0x2b0 mm/util.c:519
ksys_mmap_pgoff+0x504/0x7b0 mm/mmap.c:1635
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x44e009
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 91 18 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fefce402308 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00000000004cc4e8 RCX: 000000000044e009

RDX: 0000000000000000 RSI: 0000000000003000 RDI: 0000000020ffc000

RBP: 00000000004cc4e0 R08: 00