------------[ cut here ]------------ WARNING: kernel/rcu/tree_stall.h:1049 at rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1049, CPU#0: syz.8.2433/15414 Modules linked in: CPU: 0 UID: 0 PID: 15414 Comm: syz.8.2433 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:rcu_check_gp_start_stall+0x2e4/0x470 kernel/rcu/tree_stall.h:1049 Code: ff ff 48 c7 c7 a0 25 8e 99 be 04 00 00 00 e8 63 df 7f 00 4c 89 f7 b8 01 00 00 00 87 05 c5 f3 e5 17 85 c0 0f 85 17 ff ff ff 90 <0f> 0b 90 48 81 ff 00 6e f4 8d 74 47 48 c7 c0 a0 4f 82 8f 48 c1 e8 RSP: 0018:ffffc90000007b78 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000a06 RCX: ffffffff81a831cd RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8df46e00 RBP: ffffc90000007e30 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffffbfff331c4b4 R12: 0000000000002904 R13: 1ffff110170c771a R14: ffffffff8df46e00 R15: dffffc0000000000 FS: 00007f414ad9b6c0(0000) GS:ffff888125e35000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000008 CR3: 0000000062810000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: rcu_core+0x6a9/0x1870 kernel/rcu/tree.c:2852 handle_softirqs+0x27d/0x850 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:finish_task_switch+0x242/0x940 kernel/sched/core.c:5114 Code: 0f 84 c2 01 00 00 48 85 db 0f 85 e9 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 28 3a cc 09 e8 83 75 37 00 fb 4c 8b 65 c0 <49> 8d bc 24 48 16 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0 RSP: 0018:ffffc9000465e2f8 EFLAGS: 00000282 RAX: dc8ac842f4f99c00 RBX: 0000000000000000 RCX: dc8ac842f4f99c00 RDX: 0000000000000006 RSI: ffffffff8d7922ac RDI: ffffffff8bc08360 RBP: ffffc9000465e350 R08: ffffffff8f821f77 R09: 1ffffffff1f043ee R10: dffffc0000000000 R11: fffffbfff1f043ef R12: ffff8880283f0000 R13: dffffc0000000000 R14: ffff88802a9fdb80 R15: ffff8880b863b498 context_switch kernel/sched/core.c:5259 [inline] __schedule+0x14c4/0x5000 kernel/sched/core.c:6863 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7190 irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:kernfs_sd_compare fs/kernfs/dir.c:349 [inline] RIP: 0010:kernfs_link_sibling+0x140/0x3e0 fs/kernfs/dir.c:380 Code: ec 41 ff 89 c3 31 ff 89 c6 e8 bc 39 5d ff 85 db 0f 84 99 00 00 00 e8 6f 35 5d ff 48 bb 00 00 00 00 00 fc ff df 48 8b 44 24 20 <80> 3c 18 00 74 08 48 89 ef e8 92 91 c3 ff 49 8d 4c 24 c0 48 8b 55 RSP: 0018:ffffc9000465e738 EFLAGS: 00000293 RAX: 1ffff110050d5d19 RBX: dffffc0000000000 RCX: ffff8880283f0000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffff8880286ae8c8 R08: ffffffff82644d4c R09: ffffffff8df41a20 R10: dffffc0000000000 R11: fffffbfff1f043ef R12: ffff888082ca1310 R13: ffff8880286ae8a8 R14: 00000000562bf91e R15: ffff88803255b440 kernfs_add_one+0x1ca/0x5c0 fs/kernfs/dir.c:813 __kernfs_create_file+0x22b/0x2e0 fs/kernfs/file.c:1086 sysfs_add_file_mode_ns+0x238/0x300 fs/sysfs/file.c:313 create_files fs/sysfs/group.c:82 [inline] internal_create_group+0x667/0x1170 fs/sysfs/group.c:189 internal_create_groups fs/sysfs/group.c:229 [inline] sysfs_create_groups+0x59/0x120 fs/sysfs/group.c:255 setup_gid_attrs drivers/infiniband/core/sysfs.c:1162 [inline] ib_setup_port_attrs+0x140c/0x2070 drivers/infiniband/core/sysfs.c:1439 add_one_compat_dev+0x449/0x650 drivers/infiniband/core/device.c:1005 add_compat_devs drivers/infiniband/core/device.c:1063 [inline] enable_device_and_get+0x2a7/0x3d0 drivers/infiniband/core/device.c:1374 ib_register_device+0x111e/0x1400 drivers/infiniband/core/device.c:1487 rxe_register_device+0x1e3/0x350 drivers/infiniband/sw/rxe/rxe_verbs.c:1556 rxe_net_add+0x81/0x110 drivers/infiniband/sw/rxe/rxe_net.c:586 rxe_newlink+0xdd/0x190 drivers/infiniband/sw/rxe/rxe.c:234 nldev_newlink+0x4a5/0x5a0 drivers/infiniband/core/nldev.c:1797 rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:-1 [inline] rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline] rdma_nl_rcv+0x6ae/0x980 drivers/infiniband/core/netlink.c:259 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:742 ____sys_sendmsg+0x505/0x820 net/socket.c:2592 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2646 __sys_sendmsg net/socket.c:2678 [inline] __do_sys_sendmsg net/socket.c:2683 [inline] __se_sys_sendmsg net/socket.c:2681 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2681 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4149f8f749 Code: ff ff c3 66 2e 0f 1f 84 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 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f414ad9b038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f414a1e6180 RCX: 00007f4149f8f749 RDX: 00000000000088c4 RSI: 0000200000000080 RDI: 0000000000000009 RBP: 00007f414a013f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f414a1e6218 R14: 00007f414a1e6180 R15: 00007fff7c827fc8 ---------------- Code disassembly (best guess): 0: 0f 84 c2 01 00 00 je 0x1c8 6: 48 85 db test %rbx,%rbx 9: 0f 85 e9 01 00 00 jne 0x1f8 f: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 14: 4c 8b 75 d0 mov -0x30(%rbp),%r14 18: 4c 89 e7 mov %r12,%rdi 1b: e8 28 3a cc 09 call 0x9cc3a48 20: e8 83 75 37 00 call 0x3775a8 25: fb sti 26: 4c 8b 65 c0 mov -0x40(%rbp),%r12 * 2a: 49 8d bc 24 48 16 00 lea 0x1648(%r12),%rdi <-- trapping instruction 31: 00 32: 48 89 f8 mov %rdi,%rax 35: 48 c1 e8 03 shr $0x3,%rax 39: 42 0f b6 04 28 movzbl (%rax,%r13,1),%eax 3e: 84 c0 test %al,%al