====================================================== WARNING: possible circular locking dependency detected 6.9.0-syzkaller-12162-gf85af9d955ac #0 Not tainted ------------------------------------------------------ syz-executor.1/5119 is trying to acquire lock: ffff8880b9438828 (lock#10){+.+.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] ffff8880b9438828 (lock#10){+.+.}-{2:2}, at: __mmap_lock_do_trace_acquire_returned+0x8f/0x630 mm/mmap_lock.c:237 but task is already holding lock: ffff8880b943e7d8 (&rq->__lock){-.-.}-{2:2}, at: finish_lock_switch kernel/sched/core.c:5160 [inline] ffff8880b943e7d8 (&rq->__lock){-.-.}-{2:2}, at: finish_task_switch+0x1b2/0x870 kernel/sched/core.c:5280 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&rq->__lock){-.-.}-{2:2}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559 raw_spin_rq_lock kernel/sched/sched.h:1406 [inline] rq_lock kernel/sched/sched.h:1702 [inline] task_fork_fair+0x61/0x1e0 kernel/sched/fair.c:12710 sched_cgroup_fork+0x37c/0x410 kernel/sched/core.c:4844 copy_process+0x2217/0x3dc0 kernel/fork.c:2499 kernel_clone+0x226/0x8f0 kernel/fork.c:2797 user_mode_thread+0x132/0x1a0 kernel/fork.c:2875 rest_init+0x23/0x300 init/main.c:712 start_kernel+0x47a/0x500 init/main.c:1103 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0x99/0xa0 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x147 -> #1 (&p->pi_lock){-.-.}-{2:2}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:553 [inline] try_to_wake_up+0xb0/0x1470 kernel/sched/core.c:4262 rcu_read_unlock_special+0x3db/0x550 kernel/rcu/tree_plugin.h:655 __rcu_read_unlock+0xa1/0x110 kernel/rcu/tree_plugin.h:426 __mmap_lock_do_trace_acquire_returned+0x1f9/0x630 mm/mmap_lock.c:237 __mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline] mmap_read_trylock include/linux/mmap_lock.h:164 [inline] get_mmap_lock_carefully mm/memory.c:5715 [inline] lock_mm_and_find_vma+0x213/0x2f0 mm/memory.c:5775 do_user_addr_fault arch/x86/mm/fault.c:1361 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x1bf/0x8c0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 fault_in_readable+0x165/0x2b0 fault_in_iov_iter_readable+0x229/0x280 lib/iov_iter.c:94 generic_perform_write+0x220/0x640 mm/filemap.c:4005 ext4_buffered_write_iter+0xc6/0x350 fs/ext4/file.c:299 ext4_file_write_iter+0x1de/0x1a10 new_sync_write fs/read_write.c:497 [inline] vfs_write+0xa72/0xc90 fs/read_write.c:590 ksys_write+0x1a0/0x2c0 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (lock#10){+.+.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 local_lock_acquire include/linux/local_lock_internal.h:29 [inline] __mmap_lock_do_trace_acquire_returned+0xa8/0x630 mm/mmap_lock.c:237 __mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline] mmap_read_trylock include/linux/mmap_lock.h:164 [inline] stack_map_get_build_id_offset+0x9af/0x9d0 kernel/bpf/stackmap.c:141 __bpf_get_stack+0x4ad/0x5a0 kernel/bpf/stackmap.c:449 bpf_prog_e6cf5f9c69743609+0x42/0x46 bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline] __bpf_prog_run include/linux/filter.h:682 [inline] bpf_prog_run include/linux/filter.h:698 [inline] bpf_prog_run_array include/linux/bpf.h:2104 [inline] trace_call_bpf+0x3f5/0x8a0 kernel/trace/bpf_trace.c:147 perf_trace_run_bpf_submit+0x7c/0x1d0 kernel/events/core.c:10269 perf_trace_lock+0x388/0x490 include/trace/events/lock.h:50 trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x986/0x9f0 kernel/locking/lockdep.c:5765 __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline] _raw_spin_unlock+0x16/0x50 kernel/locking/spinlock.c:186 raw_spin_rq_unlock kernel/sched/core.c:603 [inline] raw_spin_rq_unlock_irq kernel/sched/sched.h:1417 [inline] finish_lock_switch kernel/sched/core.c:5162 [inline] finish_task_switch+0x1e0/0x870 kernel/sched/core.c:5280 context_switch kernel/sched/core.c:5411 [inline] __schedule+0x17f0/0x4a20 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6837 do_nanosleep+0x197/0x600 kernel/time/hrtimer.c:2028 hrtimer_nanosleep+0x227/0x470 kernel/time/hrtimer.c:2081 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1396 [inline] __se_sys_clock_nanosleep+0x32b/0x3c0 kernel/time/posix-timers.c:1373 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: lock#10 --> &p->pi_lock --> &rq->__lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&rq->__lock); lock(&p->pi_lock); lock(&rq->__lock); lock(lock#10); *** DEADLOCK *** 3 locks held by syz-executor.1/5119: #0: ffff8880b943e7d8 (&rq->__lock){-.-.}-{2:2}, at: finish_lock_switch kernel/sched/core.c:5160 [inline] #0: ffff8880b943e7d8 (&rq->__lock){-.-.}-{2:2}, at: finish_task_switch+0x1b2/0x870 kernel/sched/core.c:5280 #1: ffffffff8e333e60 (rcu_read_lock){....}-{1:2}, at: trace_call_bpf+0xbc/0x8a0 #2: ffff88802f43e098 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:163 [inline] #2: ffff88802f43e098 (&mm->mmap_lock){++++}-{3:3}, at: stack_map_get_build_id_offset+0x237/0x9d0 kernel/bpf/stackmap.c:141 stack backtrace: CPU: 0 PID: 5119 Comm: syz-executor.1 Not tainted 6.9.0-syzkaller-12162-gf85af9d955ac #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3869 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754 local_lock_acquire include/linux/local_lock_internal.h:29 [inline] __mmap_lock_do_trace_acquire_returned+0xa8/0x630 mm/mmap_lock.c:237 __mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline] mmap_read_trylock include/linux/mmap_lock.h:164 [inline] stack_map_get_build_id_offset+0x9af/0x9d0 kernel/bpf/stackmap.c:141 __bpf_get_stack+0x4ad/0x5a0 kernel/bpf/stackmap.c:449 bpf_prog_e6cf5f9c69743609+0x42/0x46 bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline] __bpf_prog_run include/linux/filter.h:682 [inline] bpf_prog_run include/linux/filter.h:698 [inline] bpf_prog_run_array include/linux/bpf.h:2104 [inline] trace_call_bpf+0x3f5/0x8a0 kernel/trace/bpf_trace.c:147 perf_trace_run_bpf_submit+0x7c/0x1d0 kernel/events/core.c:10269 perf_trace_lock+0x388/0x490 include/trace/events/lock.h:50 trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x986/0x9f0 kernel/locking/lockdep.c:5765 __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline] _raw_spin_unlock+0x16/0x50 kernel/locking/spinlock.c:186 raw_spin_rq_unlock kernel/sched/core.c:603 [inline] raw_spin_rq_unlock_irq kernel/sched/sched.h:1417 [inline] finish_lock_switch kernel/sched/core.c:5162 [inline] finish_task_switch+0x1e0/0x870 kernel/sched/core.c:5280 context_switch kernel/sched/core.c:5411 [inline] __schedule+0x17f0/0x4a20 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6837 do_nanosleep+0x197/0x600 kernel/time/hrtimer.c:2028 hrtimer_nanosleep+0x227/0x470 kernel/time/hrtimer.c:2081 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1396 [inline] __se_sys_clock_nanosleep+0x32b/0x3c0 kernel/time/posix-timers.c:1373 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6be48a8375 Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 f6 b9 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 4f ba ff ff 48 8b 04 24 48 83 c4 28 f7 d8 RSP: 002b:00007ffed7f7eec0 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 000000000000019d RCX: 00007f6be48a8375 RDX: 00007ffed7f7ef00 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffed7f7ef7c R08: 0000000000000000 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000032 R13: 000000000002bde0 R14: 000000000002bc99 R15: 000000000000001a