Re: possible deadlock in static_key_slow_dec

From: syzbot
Date: Fri Aug 16 2019 - 03:07:16 EST

Next message: Oleksandr Suvorov: "Re: [PATCH v4 14/21] ARM: dts: imx6ull-colibri: Add sleep mode to fec"
Previous message: Christina Quast: "[PATCH 0/2] Use ccm(aes) aead transform in staging drivers"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

syzbot has found a reproducer for the following crash on:

HEAD commit: 17da61ae Add linux-next specific files for 20190814
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=158810ac600000
kernel config: https://syzkaller.appspot.com/x/.config?x=4733704ca85aaa66
dashboard link: https://syzkaller.appspot.com/bug?extid=b011e55d1b4c015100d2
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13b5b496600000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=147935ee600000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+b011e55d1b4c015100d2@xxxxxxxxxxxxxxxxxxxxxxxxx

======================================================
WARNING: possible circular locking dependency detected
5.3.0-rc4-next-20190814 #66 Not tainted
------------------------------------------------------
syz-executor590/9351 is trying to acquire lock:
ffffffff88f5eef0 (cpu_hotplug_lock.rw_sem){++++}, at: __static_key_slow_dec kernel/jump_label.c:254 [inline]
ffffffff88f5eef0 (cpu_hotplug_lock.rw_sem){++++}, at: static_key_slow_dec+0x54/0xa0 kernel/jump_label.c:270

but task is already holding lock:
ffff8880a96354d0 (&mm->mmap_sem#2){++++}, at: vm_mmap_pgoff+0x173/0x230 mm/util.c:494

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #2 (&mm->mmap_sem#2){++++}:
down_write+0x93/0x150 kernel/locking/rwsem.c:1534
mpol_rebind_mm+0x25/0xd0 mm/mempolicy.c:382
cpuset_attach+0x226/0x420 kernel/cgroup/cpuset.c:2204
cgroup_migrate_execute+0xc56/0x1350 kernel/cgroup/cgroup.c:2524
cgroup_migrate+0x14f/0x1f0 kernel/cgroup/cgroup.c:2780
cgroup_attach_task+0x57f/0x860 kernel/cgroup/cgroup.c:2817
__cgroup1_procs_write.constprop.0+0x321/0x400 kernel/cgroup/cgroup-v1.c:522
cgroup1_procs_write+0x2b/0x40 kernel/cgroup/cgroup-v1.c:535
cgroup_file_write+0x241/0x790 kernel/cgroup/cgroup.c:3754
kernfs_fop_write+0x2b8/0x480 fs/kernfs/file.c:315
__vfs_write+0x8a/0x110 fs/read_write.c:494
vfs_write+0x268/0x5d0 fs/read_write.c:558
ksys_write+0x14f/0x290 fs/read_write.c:611
__do_sys_write fs/read_write.c:623 [inline]
__se_sys_write fs/read_write.c:620 [inline]
__x64_sys_write+0x73/0xb0 fs/read_write.c:620
do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe

-> #1 (&cpuset_rwsem){++++}:
percpu_down_read include/linux/percpu-rwsem.h:40 [inline]
cpuset_read_lock+0x3e/0x150 kernel/cgroup/cpuset.c:340
__sched_setscheduler+0xca2/0x2110 kernel/sched/core.c:4718
_sched_setscheduler+0x10a/0x1b0 kernel/sched/core.c:4890
sched_setscheduler_nocheck+0xb/0x10 kernel/sched/core.c:4936
__kthread_create_on_node+0x32a/0x460 kernel/kthread.c:349
kthread_create_on_node+0xbb/0xf0 kernel/kthread.c:388
create_worker+0x25c/0x570 kernel/workqueue.c:1929
workqueue_prepare_cpu+0xa1/0x100 kernel/workqueue.c:4982
cpuhp_invoke_callback+0x21a/0x1c60 kernel/cpu.c:172
cpuhp_up_callbacks kernel/cpu.c:593 [inline]
_cpu_up+0x289/0x550 kernel/cpu.c:1153
do_cpu_up+0x171/0x190 kernel/cpu.c:1188
cpu_up+0x1b/0x20 kernel/cpu.c:1196
smp_init+0x248/0x261 kernel/smp.c:593
kernel_init_freeable+0x339/0x5be init/main.c:1185
kernel_init+0x12/0x1c5 init/main.c:1110
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

-> #0 (cpu_hotplug_lock.rw_sem){++++}:
check_prev_add kernel/locking/lockdep.c:2476 [inline]
check_prevs_add kernel/locking/lockdep.c:2581 [inline]
validate_chain kernel/locking/lockdep.c:2971 [inline]
__lock_acquire+0x25b6/0x4e70 kernel/locking/lockdep.c:3955
lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4487
percpu_down_read include/linux/percpu-rwsem.h:40 [inline]
cpus_read_lock+0x3e/0x150 kernel/cpu.c:292
__static_key_slow_dec kernel/jump_label.c:254 [inline]
static_key_slow_dec+0x54/0xa0 kernel/jump_label.c:270
sw_perf_event_destroy+0x8b/0x130 kernel/events/core.c:8482
_free_event+0x354/0x13a0 kernel/events/core.c:4470
put_event+0x47/0x60 kernel/events/core.c:4564
perf_mmap_close+0x585/0xe00 kernel/events/core.c:5567
remove_vma+0xb2/0x180 mm/mmap.c:183
remove_vma_list mm/mmap.c:2615 [inline]
__do_munmap+0x7b0/0x10f0 mm/mmap.c:2859
do_munmap mm/mmap.c:2867 [inline]
mmap_region+0x227/0x1760 mm/mmap.c:1745
do_mmap+0x853/0x1180 mm/mmap.c:1575
do_mmap_pgoff include/linux/mm.h:2395 [inline]
vm_mmap_pgoff+0x1c5/0x230 mm/util.c:496
ksys_mmap_pgoff+0x4aa/0x630 mm/mmap.c:1625
__do_sys_mmap arch/x86/kernel/sys_x86_64.c:100 [inline]
__se_sys_mmap arch/x86/kernel/sys_x86_64.c:91 [inline]
__x64_sys_mmap+0xe9/0x1b0 arch/x86/kernel/sys_x86_64.c:91
do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe

other info that might help us debug this:

Chain exists of:
cpu_hotplug_lock.rw_sem --> &cpuset_rwsem --> &mm->mmap_sem#2

Possible unsafe locking scenario:

CPU0 CPU1
---- ----
lock(&mm->mmap_sem#2);
lock(&cpuset_rwsem);
lock(&mm->mmap_sem#2);
lock(cpu_hotplug_lock.rw_sem);

*** DEADLOCK ***

1 lock held by syz-executor590/9351:
#0: ffff8880a96354d0 (&mm->mmap_sem#2){++++}, at: vm_mmap_pgoff+0x173/0x230 mm/util.c:494

stack backtrace:
CPU: 0 PID: 9351 Comm: syz-executor590 Not tainted 5.3.0-rc4-next-20190814 #66
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x172/0x1f0 lib/dump_stack.c:113
print_circular_bug.isra.0.cold+0x163/0x172 kernel/locking/lockdep.c:1685
check_noncircular+0x32e/0x3e0 kernel/locking/lockdep.c:1809
check_prev_add kernel/locking/lockdep.c:2476 [inline]
check_prevs_add kernel/locking/lockdep.c:2581 [inline]
validate_chain kernel/locking/lockdep.c:2971 [inline]
__lock_acquire+0x25b6/0x4e70 kernel/locking/lockdep.c:3955
lock_acquire+0x190/0x410 kernel/locking/lockdep.c:4487
percpu_down_read include/linux/percpu-rwsem.h:40 [inline]
cpus_read_lock+0x3e/0x150 kernel/cpu.c:292
__static_key_slow_dec kernel/jump_label.c:254 [inline]
static_key_slow_dec+0x54/0xa0 kernel/jump_label.c:270
sw_perf_event_destroy+0x8b/0x130 kernel/events/core.c:8482
_free_event+0x354/0x13a0 kernel/events/core.c:4470
put_event+0x47/0x60 kernel/events/core.c:4564
perf_mmap_close+0x585/0xe00 kernel/events/core.c:5567
remove_vma+0xb2/0x180 mm/mmap.c:183
remove_vma_list mm/mmap.c:2615 [inline]
__do_munmap+0x7b0/0x10f0 mm/mmap.c:2859
do_munmap mm/mmap.c:2867 [inline]
mmap_region+0x227/0x1760 mm/mmap.c:1745
do_mmap+0x853/0x1180 mm/mmap.c:1575
do_mmap_pgoff include/linux/mm.h:2395 [inline]
vm_mmap_pgoff+0x1c5/0x230 mm/util.c:496
ksys_mmap_pgoff+0x4aa/0x630 mm/mmap.c:1625
__do_sys_mmap arch/x86/kernel/sys_x86_64.c:100 [inline]
__se_sys_mmap arch/x86/kernel/sys_x86_64.c:91 [inline]
__x64_sys_mmap+0xe9/0x1b0 arch/x86/kernel/sys_x86_64.c:91
do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4473b9
Code: e8 4c bb 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 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 0f 83 5b 07 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f148465bda8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00000000006dcc38 RCX: 00000000004473b9
RDX: 0000000000000000 RSI: 0000000000003000 RDI: 0000000020ffd000
RBP: 00000000006dcc30 R08: 0000000000000004 R09: 0000000000000000
R10: 0000000000000011 R11: 0000000000000246 R12: 00000000006dcc3c
R13: 00007ffd3f4be3ef R14: 00007f148465c9c0 R15: 0000000000000000

Next message: Oleksandr Suvorov: "Re: [PATCH v4 14/21] ARM: dts: imx6ull-colibri: Add sleep mode to fec"
Previous message: Christina Quast: "[PATCH 0/2] Use ccm(aes) aead transform in staging drivers"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]