====================================================== WARNING: possible circular locking dependency detected 6.10.0-syzkaller-04484-g13c9b702e6cb #0 Not tainted ------------------------------------------------------ syz.3.2080/13290 is trying to acquire lock: ffff88801728e418 (&p->pi_lock){-.-.}-{2:2}, at: class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:551 [inline] ffff88801728e418 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0xb0/0x1470 kernel/sched/core.c:4051 but task is already holding lock: ffff8880b9438798 (lock#10){+.+.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] ffff8880b9438798 (lock#10){+.+.}-{2:2}, at: __mmap_lock_do_trace_released+0x83/0x620 mm/mmap_lock.c:243 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (lock#10){+.+.}-{2:2}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5753 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_get_stack_raw_tp kernel/trace/bpf_trace.c:1997 [inline] bpf_get_stack_raw_tp+0x1a3/0x240 kernel/trace/bpf_trace.c:1987 0xffffffffa0002252 bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline] __bpf_prog_run include/linux/filter.h:691 [inline] bpf_prog_run include/linux/filter.h:698 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline] bpf_trace_run2+0x2ec/0x540 kernel/trace/bpf_trace.c:2447 trace_tlb_flush+0x118/0x140 include/trace/events/tlb.h:38 switch_mm_irqs_off+0x7cb/0xae0 context_switch kernel/sched/core.c:5172 [inline] __schedule+0x1079/0x4a60 kernel/sched/core.c:6529 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6708 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6732 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0x130/0x140 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] __wake_up_common_lock+0x18c/0x1e0 kernel/sched/wait.c:108 sock_def_readable+0x20f/0x5b0 net/core/sock.c:3374 unix_dgram_sendmsg+0x1490/0x1f80 net/unix/af_unix.c:2170 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 __sys_sendto+0x3a4/0x4f0 net/socket.c:2204 __do_sys_sendto net/socket.c:2216 [inline] __se_sys_sendto net/socket.c:2212 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2212 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 -> #1 (&rq->__lock){-.-.}-{2:2}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5753 _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:560 raw_spin_rq_lock kernel/sched/sched.h:1415 [inline] rq_lock kernel/sched/sched.h:1714 [inline] task_fork_fair+0x61/0x1e0 kernel/sched/fair.c:12710 sched_cgroup_fork+0x37c/0x410 kernel/sched/core.c:4633 copy_process+0x2217/0x3dc0 kernel/fork.c:2482 kernel_clone+0x226/0x8f0 kernel/fork.c:2780 user_mode_thread+0x132/0x1a0 kernel/fork.c:2858 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 -> #0 (&p->pi_lock){-.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3133 [inline] check_prevs_add kernel/locking/lockdep.c:3252 [inline] validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5136 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5753 __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:551 [inline] try_to_wake_up+0xb0/0x1470 kernel/sched/core.c:4051 rcu_read_unlock_special+0x3db/0x550 kernel/rcu/tree_plugin.h:665 __rcu_read_unlock+0xa1/0x110 kernel/rcu/tree_plugin.h:436 rcu_read_unlock include/linux/rcupdate.h:872 [inline] get_mem_cgroup_from_mm+0x1b2/0x2a0 mm/memcontrol.c:1271 get_mm_memcg_path+0x1b/0x600 mm/mmap_lock.c:202 __mmap_lock_do_trace_released+0x134/0x620 mm/mmap_lock.c:243 __mmap_lock_trace_released include/linux/mmap_lock.h:42 [inline] mmap_read_unlock include/linux/mmap_lock.h:170 [inline] __get_user_pages_locked mm/gup.c:1962 [inline] get_dump_page+0x2e4/0x2f0 mm/gup.c:2389 dump_user_range+0x14c/0x950 fs/coredump.c:952 elf_core_dump+0x3de6/0x4720 fs/binfmt_elf.c:2116 do_coredump+0x19e1/0x2940 fs/coredump.c:767 get_signal+0x13fa/0x1740 kernel/signal.c:2902 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231 exc_page_fault+0x590/0x8c0 arch/x86/mm/fault.c:1542 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 other info that might help us debug this: Chain exists of: &p->pi_lock --> &rq->__lock --> lock#10 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(lock#10); lock(&rq->__lock); lock(lock#10); lock(&p->pi_lock); *** DEADLOCK *** 3 locks held by syz.3.2080/13290: #0: ffff88807f3e8420 (sb_writers#5){.+.+}-{0:0}, at: do_coredump+0x19a9/0x2940 fs/coredump.c:766 #1: ffff88802bf0f398 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock_killable include/linux/mmap_lock.h:153 [inline] #1: ffff88802bf0f398 (&mm->mmap_lock){++++}-{3:3}, at: __get_user_pages_locked mm/gup.c:1846 [inline] #1: ffff88802bf0f398 (&mm->mmap_lock){++++}-{3:3}, at: get_dump_page+0xe2/0x2f0 mm/gup.c:2389 #2: ffff8880b9438798 (lock#10){+.+.}-{2:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] #2: ffff8880b9438798 (lock#10){+.+.}-{2:2}, at: __mmap_lock_do_trace_released+0x83/0x620 mm/mmap_lock.c:243 stack backtrace: CPU: 0 PID: 13290 Comm: syz.3.2080 Not tainted 6.10.0-syzkaller-04484-g13c9b702e6cb #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 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:2186 check_prev_add kernel/locking/lockdep.c:3133 [inline] check_prevs_add kernel/locking/lockdep.c:3252 [inline] validate_chain+0x18e0/0x5900 kernel/locking/lockdep.c:3868 __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5136 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5753 __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:551 [inline] try_to_wake_up+0xb0/0x1470 kernel/sched/core.c:4051 rcu_read_unlock_special+0x3db/0x550 kernel/rcu/tree_plugin.h:665 __rcu_read_unlock+0xa1/0x110 kernel/rcu/tree_plugin.h:436 rcu_read_unlock include/linux/rcupdate.h:872 [inline] get_mem_cgroup_from_mm+0x1b2/0x2a0 mm/memcontrol.c:1271 get_mm_memcg_path+0x1b/0x600 mm/mmap_lock.c:202 __mmap_lock_do_trace_released+0x134/0x620 mm/mmap_lock.c:243 __mmap_lock_trace_released include/linux/mmap_lock.h:42 [inline] mmap_read_unlock include/linux/mmap_lock.h:170 [inline] __get_user_pages_locked mm/gup.c:1962 [inline] get_dump_page+0x2e4/0x2f0 mm/gup.c:2389 dump_user_range+0x14c/0x950 fs/coredump.c:952 elf_core_dump+0x3de6/0x4720 fs/binfmt_elf.c:2116 do_coredump+0x19e1/0x2940 fs/coredump.c:767 get_signal+0x13fa/0x1740 kernel/signal.c:2902 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231 exc_page_fault+0x590/0x8c0 arch/x86/mm/fault.c:1542 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f16cdc3a037 Code: 95 1a 00 e8 1b fc ff ff 48 8d 3d c5 95 1a 00 e8 0f fc ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 53 89 fb 48 83 ec 10 <64> 8b 04 25 94 ff ff ff 85 c0 74 2a 89 fe 31 c0 bf 3c 00 00 00 e8 RSP: 002b:00000000200003e0 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 000000000000000b RCX: 00007f16cdd75f19 RDX: 0000000020000400 RSI: 0000000020000530 RDI: 000000000000000b RBP: 00007f16cdde4e68 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000020001080 R11: 0000000000000206 R12: 0000000000000000 R13: 000000000000000b R14: 00007f16cdf05f60 R15: 00007ffc77297ea8