================================ WARNING: inconsistent lock state syzkaller #0 Not tainted -------------------------------- inconsistent {INITIAL USE} -> {IN-NMI} usage. syz.4.3553/17317 [HC1[1]:SC0[0]:HE0:SE1] takes: ffffffff8cc845f8 (kernfs_rename_lock){....}-{2:2}, at: kernfs_path_from_node+0x85/0xd30 fs/kernfs/dir.c:232 {INITIAL USE} state was registered at: lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xab/0xf0 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:376 [inline] kernfs_rename_ns+0x550/0x990 fs/kernfs/dir.c:1734 sysfs_rename_link_ns+0x171/0x1b0 fs/sysfs/symlink.c:192 device_rename+0x11c/0x1a0 drivers/base/core.c:4577 dev_change_name+0x376/0x900 net/core/dev.c:1273 do_setlink+0x93d/0x3e60 net/core/rtnetlink.c:2817 __rtnl_newlink net/core/rtnetlink.c:3614 [inline] rtnl_newlink+0x17d9/0x20a0 net/core/rtnetlink.c:3661 rtnetlink_rcv_msg+0x87c/0xfc0 net/core/rtnetlink.c:6158 netlink_rcv_skb+0x1fb/0x450 net/netlink/af_netlink.c:2511 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x74d/0x8d0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ad/0xbd0 net/netlink/af_netlink.c:1872 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] __sys_sendto+0x497/0x650 net/socket.c:2152 __do_sys_sendto net/socket.c:2164 [inline] __se_sys_sendto net/socket.c:2160 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2160 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 irq event stamp: 446 hardirqs last enabled at (445): [] do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82 hardirqs last disabled at (446): [] exc_debug_user arch/x86/kernel/traps.c:1118 [inline] hardirqs last disabled at (446): [] noist_exc_debug+0x49/0x120 arch/x86/kernel/traps.c:1181 softirqs last enabled at (394): [] rcu_lock_acquire include/linux/rcupdate.h:350 [inline] softirqs last enabled at (394): [] rcu_read_lock include/linux/rcupdate.h:791 [inline] softirqs last enabled at (394): [] __rhashtable_insert_fast include/linux/rhashtable.h:713 [inline] softirqs last enabled at (394): [] rhltable_insert_key include/linux/rhashtable.h:852 [inline] softirqs last enabled at (394): [] rhltable_insert include/linux/rhashtable.h:879 [inline] softirqs last enabled at (394): [] toggle_bp_slot+0x199c/0x2bc0 kernel/events/hw_breakpoint.c:521 softirqs last disabled at (392): [] local_bh_disable include/linux/bottom_half.h:20 [inline] softirqs last disabled at (392): [] rht_lock+0x1c/0x150 include/linux/rhashtable.h:329 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(kernfs_rename_lock); lock(kernfs_rename_lock); *** DEADLOCK *** 2 locks held by syz.4.3553/17317: #0: ffffffff8cb2de60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8cb2de60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8cb2de60 (rcu_read_lock){....}-{1:2}, at: atomic_notifier_call_chain+0x2c/0x2b0 kernel/notifier.c:224 #1: ffffffff8cb2de60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #1: ffffffff8cb2de60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #1: ffffffff8cb2de60 (rcu_read_lock){....}-{1:2}, at: __perf_event_output kernel/events/core.c:7728 [inline] #1: ffffffff8cb2de60 (rcu_read_lock){....}-{1:2}, at: perf_event_output_forward+0xbe/0x2f0 kernel/events/core.c:7750 stack backtrace: CPU: 0 PID: 17317 Comm: syz.4.3553 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: <#DB> dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 lock_acquire+0x2df/0x4a0 kernel/locking/lockdep.c:5653 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162 kernfs_path_from_node+0x85/0xd30 fs/kernfs/dir.c:232 kernfs_path include/linux/kernfs.h:595 [inline] cgroup_path include/linux/cgroup.h:674 [inline] get_mm_memcg_path+0xb9/0x360 mm/mmap_lock.c:82 __mmap_lock_do_trace_start_locking+0xe3/0x380 mm/mmap_lock.c:95 __mmap_lock_trace_start_locking include/linux/mmap_lock.h:29 [inline] mmap_read_trylock include/linux/mmap_lock.h:135 [inline] stack_map_get_build_id_offset+0x68c/0x970 kernel/bpf/stackmap.c:144 __bpf_get_stackid+0x55d/0x920 kernel/bpf/stackmap.c:250 bpf_prog_12712c88fd19bd5b+0x21/0x25 bpf_dispatcher_nop_func include/linux/bpf.h:1012 [inline] __bpf_prog_run include/linux/filter.h:607 [inline] bpf_prog_run include/linux/filter.h:614 [inline] bpf_overflow_handler+0x522/0x7c0 kernel/events/core.c:10321 __perf_event_overflow+0x448/0x610 kernel/events/core.c:9496 perf_swevent_overflow kernel/events/core.c:9579 [inline] perf_swevent_event+0x315/0x570 kernel/events/core.c:9630 perf_bp_event+0x312/0x3f0 kernel/events/core.c:10518 hw_breakpoint_handler arch/x86/kernel/hw_breakpoint.c:555 [inline] hw_breakpoint_exceptions_notify+0x21a/0x470 arch/x86/kernel/hw_breakpoint.c:586 notifier_call_chain kernel/notifier.c:87 [inline] atomic_notifier_call_chain+0x17a/0x2b0 kernel/notifier.c:225 notify_die+0x141/0x1a0 kernel/notifier.c:593 notify_debug+0x20/0x30 arch/x86/kernel/traps.c:1018 exc_debug_kernel arch/x86/kernel/traps.c:1075 [inline] exc_debug+0xd9/0x130 arch/x86/kernel/traps.c:1175 asm_exc_debug+0x1a/0x40 arch/x86/include/asm/idtentry.h:648 RIP: 0010:__get_user_nocheck_8+0x9/0x13 arch/x86/lib/getuser.S:160 Code: 90 0f 01 cb 0f ae e8 0f b7 10 31 c0 0f 01 ca c3 90 0f 01 cb 0f ae e8 8b 10 31 c0 0f 01 ca c3 90 90 0f 01 cb 0f ae e8 48 8b 10 <31> c0 0f 01 ca c3 90 0f 01 ca 31 d2 48 c7 c0 f2 ff ff ff c3 00 00 RSP: 0000:ffffc9000fe87600 EFLAGS: 00040802 RAX: 0000200000000300 RBX: dffffc0000000000 RCX: ffff8880207d0000 RDX: 00006370692f736e RSI: 0000200000000300 RDI: 00007fffffffeff0 RBP: 0000000000000000 R08: 000000000000007f R09: 0000000000000000 R10: dffffc0000000000 R11: fffff52001fd0f1f R12: 00000000ffffffff R13: 0000200000000300 R14: 000000000000007f R15: 00007fffffffeff0 perf_callchain_user+0x55d/0x13c0 arch/x86/events/core.c:2982 get_perf_callchain+0x39e/0x490 kernel/events/callchain.c:219 perf_callchain kernel/events/core.c:7512 [inline] perf_prepare_sample+0x399/0x2020 kernel/events/core.c:7545 __perf_event_output kernel/events/core.c:7730 [inline] perf_event_output_forward+0x197/0x2f0 kernel/events/core.c:7750 __perf_event_overflow+0x448/0x610 kernel/events/core.c:9496 perf_swevent_overflow+0x19b/0x230 kernel/events/core.c:9579 perf_swevent_event+0x458/0x570 kernel/events/core.c:-1 perf_bp_event+0x312/0x3f0 kernel/events/core.c:10518 hw_breakpoint_handler arch/x86/kernel/hw_breakpoint.c:555 [inline] hw_breakpoint_exceptions_notify+0x152/0x470 arch/x86/kernel/hw_breakpoint.c:586 notifier_call_chain kernel/notifier.c:87 [inline] atomic_notifier_call_chain+0x17a/0x2b0 kernel/notifier.c:225 notify_die+0x141/0x1a0 kernel/notifier.c:593 notify_debug+0x20/0x30 arch/x86/kernel/traps.c:1018 exc_debug_user arch/x86/kernel/traps.c:1144 [inline] noist_exc_debug+0x73/0x120 arch/x86/kernel/traps.c:1181 asm_exc_debug+0x2f/0x40 arch/x86/include/asm/idtentry.h:648 RIP: 0033:0x7f36cd37bbfd Code: 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 89 f8 48 89 fa c5 f9 ef c0 25 ff 0f 00 00 3d e0 0f 00 00 0f 87 27 01 00 00 c5 fd 74 0f fd d7 c1 85 c0 74 5b f3 0f bc c0 e9 30 01 00 00 66 90 f3 0f bc RSP: 002b:00007f36ce2308a8 EFLAGS: 00000283 RAX: 0000000000000300 RBX: 00007f36ce230de0 RCX: 2f666c65732f636f RDX: 0000200000000300 RSI: 00007f36cd45d140 RDI: 0000200000000300 RBP: 0000200000000300 R08: 00007f36ce231010 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000073 R14: 00007f36cd4320dd R15: 00007f36ce230ea0 ---------------- Code disassembly (best guess): 0: 90 nop 1: 0f 01 cb stac 4: 0f ae e8 lfence 7: 0f b7 10 movzwl (%rax),%edx a: 31 c0 xor %eax,%eax c: 0f 01 ca clac f: c3 ret 10: 90 nop 11: 0f 01 cb stac 14: 0f ae e8 lfence 17: 8b 10 mov (%rax),%edx 19: 31 c0 xor %eax,%eax 1b: 0f 01 ca clac 1e: c3 ret 1f: 90 nop 20: 90 nop 21: 0f 01 cb stac 24: 0f ae e8 lfence 27: 48 8b 10 mov (%rax),%rdx * 2a: 31 c0 xor %eax,%eax <-- trapping instruction 2c: 0f 01 ca clac 2f: c3 ret 30: 90 nop 31: 0f 01 ca clac 34: 31 d2 xor %edx,%edx 36: 48 c7 c0 f2 ff ff ff mov $0xfffffffffffffff2,%rax 3d: c3 ret