================================ WARNING: inconsistent lock state syzkaller #0 Not tainted -------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. syz.0.1183/9261 [HC0[0]:SC1[1]:HE1:SE0] takes: ffff88807e00e120 (sk_lock-AF_X25){+.?.}-{0:0}, at: lock_sock include/net/sock.h:1744 [inline] ffff88807e00e120 (sk_lock-AF_X25){+.?.}-{0:0}, at: x25_kill_by_neigh+0x109/0x250 net/x25/af_x25.c:1779 {SOFTIRQ-ON-W} state was registered at: lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623 lock_sock_nested+0x44/0x100 net/core/sock.c:3258 lock_sock include/net/sock.h:1744 [inline] x25_ioctl+0x449/0xe20 net/x25/af_x25.c:1567 sock_do_ioctl+0xfb/0x320 net/socket.c:1148 sock_ioctl+0x48a/0x700 net/socket.c:1267 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 irq event stamp: 45320 hardirqs last enabled at (45320): [] __local_bh_enable_ip+0x136/0x1c0 kernel/softirq.c:406 hardirqs last disabled at (45319): [] __local_bh_enable_ip+0xd7/0x1c0 kernel/softirq.c:383 softirqs last enabled at (42504): [] __do_softirq kernel/softirq.c:610 [inline] softirqs last enabled at (42504): [] invoke_softirq kernel/softirq.c:450 [inline] softirqs last enabled at (42504): [] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659 softirqs last disabled at (45237): [] __do_softirq kernel/softirq.c:610 [inline] softirqs last disabled at (45237): [] invoke_softirq kernel/softirq.c:450 [inline] softirqs last disabled at (45237): [] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(sk_lock-AF_X25); lock(sk_lock-AF_X25); *** DEADLOCK *** 3 locks held by syz.0.1183/9261: #0: ffff88801e774728 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:117 [inline] #0: ffff88801e774728 (&mm->mmap_lock){++++}-{3:3}, at: __mm_populate+0x164/0x3b0 mm/gup.c:1618 #1: ffffffff8c31ef60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:312 #2: ffffffff8c31ef60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:313 stack backtrace: CPU: 0 PID: 9261 Comm: syz.0.1183 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 valid_state+0x13b/0x1d0 kernel/locking/lockdep.c:3932 mark_lock_irq+0xa9/0x900 kernel/locking/lockdep.c:4135 mark_lock+0x208/0x320 kernel/locking/lockdep.c:4591 mark_usage kernel/locking/lockdep.c:-1 [inline] __lock_acquire+0xc63/0x7b50 kernel/locking/lockdep.c:4966 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623 lock_sock_nested+0x44/0x100 net/core/sock.c:3258 lock_sock include/net/sock.h:1744 [inline] x25_kill_by_neigh+0x109/0x250 net/x25/af_x25.c:1779 x25_lapb_receive_frame+0x19d/0xf20 net/x25/x25_dev.c:138 __netif_receive_skb_one_core net/core/dev.c:5551 [inline] netif_receive_skb_core+0x149/0x210 net/core/dev.c:5576 lapbeth_napi_poll+0x3e/0x80 drivers/net/wan/lapbether.c:99 __napi_poll+0xbb/0x430 net/core/dev.c:7101 napi_poll net/core/dev.c:7168 [inline] net_rx_action+0x522/0xa80 net/core/dev.c:7258 handle_softirqs+0x336/0x830 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] RIP: 0010:rcu_read_lock_sched_held+0xe8/0x110 kernel/rcu/update.c:125 Code: 05 25 74 9e 7e bb 01 00 00 00 a9 ff ff ff 7f 75 c0 48 b8 04 00 00 00 00 fc ff df 41 c6 04 06 00 48 c7 44 24 20 00 00 00 00 9c <8f> 44 24 20 31 db f7 44 24 20 00 02 00 00 41 c6 04 06 f8 0f 94 c3 RSP: 0018:ffffc90002f6f3d8 EFLAGS: 00000246 RAX: dffffc0000000004 RBX: 0000000000000001 RCX: 4f30ff161a741900 RDX: 0000000000000002 RSI: ffffffff8a2b3e80 RDI: ffffffff8a7a43c0 RBP: ffffc90002f6f458 R08: dffffc0000000000 R09: 1ffffffff203de18 R10: dffffc0000000000 R11: fffffbfff203de19 R12: dffffc0000000000 R13: dffffc0000000000 R14: 1ffff920005ede7c R15: dffffc0000000000 task_css include/linux/cgroup.h:496 [inline] blk_cgroup_congested include/linux/blk-cgroup.h:283 [inline] __cgroup_throttle_swaprate+0x147/0x530 mm/swapfile.c:3809 cgroup_throttle_swaprate include/linux/swap.h:728 [inline] shmem_add_to_page_cache+0xb7e/0x14d0 mm/shmem.c:727 shmem_getpage_gfp+0x1735/0x2c10 mm/shmem.c:1940 shmem_fault+0x1ac/0x550 mm/shmem.c:2118 __do_fault+0x141/0x330 mm/memory.c:3928 do_read_fault mm/memory.c:4264 [inline] do_fault mm/memory.c:4392 [inline] handle_pte_fault mm/memory.c:4650 [inline] __handle_mm_fault mm/memory.c:4785 [inline] handle_mm_fault+0x2982/0x4440 mm/memory.c:4883 faultin_page mm/gup.c:976 [inline] __get_user_pages+0x952/0x11e0 mm/gup.c:1197 populate_vma_page_range+0x213/0x290 mm/gup.c:1529 __mm_populate+0x275/0x3b0 mm/gup.c:1638 mm_populate include/linux/mm.h:2646 [inline] vm_mmap_pgoff+0x212/0x2d0 mm/util.c:556 ksys_mmap_pgoff+0x140/0x790 mm/mmap.c:1635 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7ff14ad13159 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ff148f6b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007ff14af9afa0 RCX: 00007ff14ad13159 RDX: b635773f04ebbeef RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007ff14adaa024 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff14af9b038 R14: 00007ff14af9afa0 R15: 00007ffc4fc628d8 BUG: sleeping function called from invalid context at net/core/sock.c:3260 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 9261, name: syz.0.1183 INFO: lockdep is turned off. Preemption disabled at: [] softirq_handle_begin kernel/softirq.c:414 [inline] [] handle_softirqs+0xfd/0x830 kernel/softirq.c:552 CPU: 0 PID: 9261 Comm: syz.0.1183 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 ___might_sleep+0x493/0x610 kernel/sched/core.c:9658 lock_sock_nested+0x5b/0x100 net/core/sock.c:3260 lock_sock include/net/sock.h:1744 [inline] x25_kill_by_neigh+0x109/0x250 net/x25/af_x25.c:1779 x25_lapb_receive_frame+0x19d/0xf20 net/x25/x25_dev.c:138 __netif_receive_skb_one_core net/core/dev.c:5551 [inline] netif_receive_skb_core+0x149/0x210 net/core/dev.c:5576 lapbeth_napi_poll+0x3e/0x80 drivers/net/wan/lapbether.c:99 __napi_poll+0xbb/0x430 net/core/dev.c:7101 napi_poll net/core/dev.c:7168 [inline] net_rx_action+0x522/0xa80 net/core/dev.c:7258 handle_softirqs+0x336/0x830 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] RIP: 0010:rcu_read_lock_sched_held+0xe8/0x110 kernel/rcu/update.c:125 Code: 05 25 74 9e 7e bb 01 00 00 00 a9 ff ff ff 7f 75 c0 48 b8 04 00 00 00 00 fc ff df 41 c6 04 06 00 48 c7 44 24 20 00 00 00 00 9c <8f> 44 24 20 31 db f7 44 24 20 00 02 00 00 41 c6 04 06 f8 0f 94 c3 RSP: 0018:ffffc90002f6f3d8 EFLAGS: 00000246 RAX: dffffc0000000004 RBX: 0000000000000001 RCX: 4f30ff161a741900 RDX: 0000000000000002 RSI: ffffffff8a2b3e80 RDI: ffffffff8a7a43c0 RBP: ffffc90002f6f458 R08: dffffc0000000000 R09: 1ffffffff203de18 R10: dffffc0000000000 R11: fffffbfff203de19 R12: dffffc0000000000 R13: dffffc0000000000 R14: 1ffff920005ede7c R15: dffffc0000000000 task_css include/linux/cgroup.h:496 [inline] blk_cgroup_congested include/linux/blk-cgroup.h:283 [inline] __cgroup_throttle_swaprate+0x147/0x530 mm/swapfile.c:3809 cgroup_throttle_swaprate include/linux/swap.h:728 [inline] shmem_add_to_page_cache+0xb7e/0x14d0 mm/shmem.c:727 shmem_getpage_gfp+0x1735/0x2c10 mm/shmem.c:1940 shmem_fault+0x1ac/0x550 mm/shmem.c:2118 __do_fault+0x141/0x330 mm/memory.c:3928 do_read_fault mm/memory.c:4264 [inline] do_fault mm/memory.c:4392 [inline] handle_pte_fault mm/memory.c:4650 [inline] __handle_mm_fault mm/memory.c:4785 [inline] handle_mm_fault+0x2982/0x4440 mm/memory.c:4883 faultin_page mm/gup.c:976 [inline] __get_user_pages+0x952/0x11e0 mm/gup.c:1197 populate_vma_page_range+0x213/0x290 mm/gup.c:1529 __mm_populate+0x275/0x3b0 mm/gup.c:1638 mm_populate include/linux/mm.h:2646 [inline] vm_mmap_pgoff+0x212/0x2d0 mm/util.c:556 ksys_mmap_pgoff+0x140/0x790 mm/mmap.c:1635 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7ff14ad13159 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ff148f6b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007ff14af9afa0 RCX: 00007ff14ad13159 RDX: b635773f04ebbeef RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007ff14adaa024 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff14af9b038 R14: 00007ff14af9afa0 R15: 00007ffc4fc628d8 ---------------- Code disassembly (best guess): 0: 05 25 74 9e 7e add $0x7e9e7425,%eax 5: bb 01 00 00 00 mov $0x1,%ebx a: a9 ff ff ff 7f test $0x7fffffff,%eax f: 75 c0 jne 0xffffffd1 11: 48 b8 04 00 00 00 00 movabs $0xdffffc0000000004,%rax 18: fc ff df 1b: 41 c6 04 06 00 movb $0x0,(%r14,%rax,1) 20: 48 c7 44 24 20 00 00 movq $0x0,0x20(%rsp) 27: 00 00 29: 9c pushf * 2a: 8f 44 24 20 pop 0x20(%rsp) <-- trapping instruction 2e: 31 db xor %ebx,%ebx 30: f7 44 24 20 00 02 00 testl $0x200,0x20(%rsp) 37: 00 38: 41 c6 04 06 f8 movb $0xf8,(%r14,%rax,1) 3d: 0f 94 c3 sete %bl