====================================================== WARNING: possible circular locking dependency detected 5.15.162-syzkaller #0 Not tainted ------------------------------------------------------ syz.1.1321/8022 is trying to acquire lock: ffff888012a10a28 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0xae/0x1300 kernel/sched/core.c:4030 but task is already holding lock: ffff8880b9b35bb8 (lock#9){+.+.}-{2:2}, at: local_lock_acquire+0xd/0x170 include/linux/local_lock_internal.h:28 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (lock#9){+.+.}-{2:2}: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 local_lock_acquire+0x29/0x170 include/linux/local_lock_internal.h:29 __mmap_lock_do_trace_acquire_returned+0x7c/0x340 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:137 [inline] stack_map_get_build_id_offset+0x612/0x930 kernel/bpf/stackmap.c:185 __bpf_get_stack+0x495/0x570 kernel/bpf/stackmap.c:496 ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1490 [inline] bpf_get_stack_raw_tp+0x1b2/0x220 kernel/trace/bpf_trace.c:1480 0xffffffffa0034e7a bpf_dispatcher_nop_func include/linux/bpf.h:790 [inline] __bpf_prog_run include/linux/filter.h:628 [inline] bpf_prog_run include/linux/filter.h:635 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:1880 [inline] bpf_trace_run2+0x19e/0x340 kernel/trace/bpf_trace.c:1917 trace_tlb_flush+0xed/0x110 include/trace/events/tlb.h:38 switch_mm_irqs_off+0x748/0xa30 context_switch kernel/sched/core.c:5016 [inline] __schedule+0x1167/0x45b0 kernel/sched/core.c:6376 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6552 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6577 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 try_to_wake_up+0x8a8/0x1300 kernel/sched/core.c:4152 wake_up_process kernel/sched/core.c:4215 [inline] wake_up_q+0x8b/0xd0 kernel/sched/core.c:950 futex_wake+0x607/0x750 kernel/futex/core.c:1702 do_futex+0x1394/0x1810 kernel/futex/core.c:3987 __do_sys_futex kernel/futex/core.c:4059 [inline] __se_sys_futex+0x407/0x490 kernel/futex/core.c:4040 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 -> #1 (&rq->__lock){-.-.}-{2:2}: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 _raw_spin_lock_nested+0x2d/0x40 kernel/locking/spinlock.c:368 raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475 raw_spin_rq_lock kernel/sched/sched.h:1326 [inline] rq_lock kernel/sched/sched.h:1621 [inline] task_fork_fair+0x5d/0x350 kernel/sched/fair.c:11495 sched_cgroup_fork+0x2d3/0x330 kernel/sched/core.c:4466 copy_process+0x224a/0x3ef0 kernel/fork.c:2320 kernel_clone+0x210/0x960 kernel/fork.c:2604 kernel_thread+0x168/0x1e0 kernel/fork.c:2656 rest_init+0x21/0x330 init/main.c:706 start_kernel+0x48c/0x540 init/main.c:1140 secondary_startup_64_no_verify+0xb1/0xbb -> #0 (&p->pi_lock){-.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 try_to_wake_up+0xae/0x1300 kernel/sched/core.c:4030 rcu_read_unlock_special+0x3aa/0x520 kernel/rcu/tree_plugin.h:650 __rcu_read_unlock+0x92/0x100 kernel/rcu/tree_plugin.h:422 rcu_read_unlock include/linux/rcupdate.h:771 [inline] put_memcg_path_buf+0xde/0x100 mm/mmap_lock.c:153 __mmap_lock_do_trace_acquire_returned+0x12f/0x340 mm/mmap_lock.c:237 __mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline] mmap_read_lock_killable include/linux/mmap_lock.h:127 [inline] get_dump_page+0x83e/0x8a0 mm/gup.c:1836 dump_user_range+0x64/0x320 fs/coredump.c:945 elf_core_dump+0x3c7d/0x4570 fs/binfmt_elf.c:2285 do_coredump+0x1852/0x31e0 fs/coredump.c:826 get_signal+0xc06/0x14e0 kernel/signal.c:2875 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:320 exc_general_protection+0x358/0x4f0 arch/x86/kernel/traps.c:562 asm_exc_general_protection+0x22/0x30 arch/x86/include/asm/idtentry.h:562 other info that might help us debug this: Chain exists of: &p->pi_lock --> &rq->__lock --> lock#9 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(lock#9); lock(&rq->__lock); lock(lock#9); lock(&p->pi_lock); *** DEADLOCK *** 4 locks held by syz.1.1321/8022: #0: ffff888076268460 (sb_writers#3){.+.+}-{0:0}, at: do_coredump+0x1825/0x31e0 fs/coredump.c:825 #1: ffff888023d1b928 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock_killable include/linux/mmap_lock.h:126 [inline] #1: ffff888023d1b928 (&mm->mmap_lock){++++}-{3:3}, at: get_dump_page+0x11a/0x8a0 mm/gup.c:1836 #2: ffff8880b9b35bb8 (lock#9){+.+.}-{2:2}, at: local_lock_acquire+0xd/0x170 include/linux/local_lock_internal.h:28 #3: ffffffff8c91fb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311 stack backtrace: CPU: 1 PID: 8022 Comm: syz.1.1321 Not tainted 5.15.162-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 check_noncircular+0x2f8/0x3b0 kernel/locking/lockdep.c:2133 check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 try_to_wake_up+0xae/0x1300 kernel/sched/core.c:4030 rcu_read_unlock_special+0x3aa/0x520 kernel/rcu/tree_plugin.h:650 __rcu_read_unlock+0x92/0x100 kernel/rcu/tree_plugin.h:422 rcu_read_unlock include/linux/rcupdate.h:771 [inline] put_memcg_path_buf+0xde/0x100 mm/mmap_lock.c:153 __mmap_lock_do_trace_acquire_returned+0x12f/0x340 mm/mmap_lock.c:237 __mmap_lock_trace_acquire_returned include/linux/mmap_lock.h:36 [inline] mmap_read_lock_killable include/linux/mmap_lock.h:127 [inline] get_dump_page+0x83e/0x8a0 mm/gup.c:1836 dump_user_range+0x64/0x320 fs/coredump.c:945 elf_core_dump+0x3c7d/0x4570 fs/binfmt_elf.c:2285 do_coredump+0x1852/0x31e0 fs/coredump.c:826 get_signal+0xc06/0x14e0 kernel/signal.c:2875 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:320 exc_general_protection+0x358/0x4f0 arch/x86/kernel/traps.c:562 asm_exc_general_protection+0x22/0x30 arch/x86/include/asm/idtentry.h:562 RIP: 0033:0x7efd32247a21 Code: 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 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f RSP: 002b:00000000200002a0 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007efd323d5f60 RCX: 00007efd32247a19 RDX: 0000000020000040 RSI: 00000000200002a0 RDI: 0000000000000400 RBP: 00007efd322b6e49 R08: 0000000020000300 R09: 0000000020000300 R10: 00000000200002c0 R11: 0000000000000206 R12: 0000000000000000 R13: 000000000000000b R14: 00007efd323d5f60 R15: 00007ffdebf748e8