vcan0: j1939_tp_rxtimer: 0xffff888051fff800: rx timeout, send abort vcan0: j1939_tp_rxtimer: 0xffff888051fff800: abort rx timeout. Force session deactivation rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P12558/1:b..l P12555/1:b..l rcu: (detected by 0, t=10502 jiffies, g=49205, q=738 ncpus=2) task:syz.0.1639 state:R running task stack:26376 pid:12555 tgid:12547 ppid:11229 task_flags:0x400040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7288 irqentry_exit+0x36/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:114 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:128 [inline] RIP: 0010:lock_acquire kernel/locking/lockdep.c:5864 [inline] RIP: 0010:lock_acquire+0x133/0x350 kernel/locking/lockdep.c:5825 Code: 00 65 8b 05 97 27 3f 12 85 c0 0f 85 a2 00 00 00 65 48 8b 05 d7 e5 3e 12 8b 90 ec 0a 00 00 85 d2 0f 85 8c 00 00 00 9c 8f 04 24 48 c7 c7 69 59 f4 8d e8 70 8a fc 09 45 89 e0 89 e9 44 89 ea 65 RSP: 0000:ffffc900036c7700 EFLAGS: 00000246 RAX: ffff888051210000 RBX: ffffffff8e5c1260 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff816ae581 RDI: fffffbfff1cb824c RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000093927 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:243 [inline] __kasan_slab_free+0x60/0x70 mm/kasan/common.c:275 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2422 [inline] slab_free mm/slub.c:4695 [inline] kfree+0x2b4/0x4d0 mm/slub.c:4894 skb_kfree_head net/core/skbuff.c:1047 [inline] skb_free_head+0x114/0x210 net/core/skbuff.c:1059 skb_release_data+0x795/0x9e0 net/core/skbuff.c:1086 skb_release_all net/core/skbuff.c:1151 [inline] __kfree_skb net/core/skbuff.c:1165 [inline] sk_skb_reason_drop+0x129/0x1a0 net/core/skbuff.c:1203 kfree_skb_reason include/linux/skbuff.h:1275 [inline] unix_release_sock+0x7f4/0x1530 net/unix/af_unix.c:726 unix_release+0x91/0xf0 net/unix/af_unix.c:1196 __sock_release+0xb0/0x270 net/socket.c:649 sock_close+0x1c/0x30 net/socket.c:1439 __fput+0x402/0xb70 fs/file_table.c:468 task_work_run+0x150/0x240 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xeb/0x110 kernel/entry/common.c:43 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8ffef8ebe9 RSP: 002b:00007f8fffd23038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: 0000000000010106 RBX: 00007f8fff1c6090 RCX: 00007f8ffef8ebe9 RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003 RBP: 00007f8fff011e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8fff1c6128 R14: 00007f8fff1c6090 R15: 00007ffc11cce118 task:syz.0.1639 state:R running task stack:26168 pid:12558 tgid:12547 ppid:11229 task_flags:0x400140 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7288 irqentry_exit+0x36/0x90 kernel/entry/common.c:197 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5872 Code: e6 3e 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 22 a2 13 0f 0f 82 74 02 00 00 8b 35 da d3 13 0f 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 79 e6 3e 12 0f 85 c7 02 00 00 48 83 c4 RSP: 0018:ffffc9000417eca0 EFLAGS: 00000206 RAX: 0000000000000046 RBX: ffffffff8e5c1260 RCX: 00000000f28deb84 RDX: 0000000000000000 RSI: ffffffff8de2cdb8 RDI: ffffffff8c162d80 RBP: 0000000000000002 R08: 3d5a26fa73f1642f R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 save_stack+0x160/0x1f0 mm/page_owner.c:156 __set_page_owner+0x91/0x550 mm/page_owner.c:329 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x132b/0x38e0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:5148 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 folio_alloc_mpol_noprof+0x36/0x2f0 mm/mempolicy.c:2435 shmem_alloc_folio+0x135/0x160 mm/shmem.c:1908 shmem_alloc_and_add_folio+0x499/0xc20 mm/shmem.c:1947 shmem_get_folio_gfp+0x67f/0x1600 mm/shmem.c:2597 shmem_get_folio mm/shmem.c:2703 [inline] shmem_write_begin+0x160/0x300 mm/shmem.c:3353 generic_perform_write+0x3c2/0x900 mm/filemap.c:4175 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3528 iter_file_splice_write+0xa24/0x12e0 fs/splice.c:738 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x18f/0x6c0 fs/splice.c:1161 splice_direct_to_actor+0x345/0xa30 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x174/0x240 fs/splice.c:1230 do_sendfile+0xb06/0xe50 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1431 [inline] __se_sys_sendfile64 fs/read_write.c:1417 [inline] __x64_sys_sendfile64+0x1d8/0x220 fs/read_write.c:1417 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8ffef8ebe9 RSP: 002b:00007f8ffcdd3038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f8fff1c6270 RCX: 00007f8ffef8ebe9 RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000008 RBP: 00007f8fff011e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0001000000201005 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8fff1c6308 R14: 00007f8fff1c6270 R15: 00007ffc11cce118 rcu: rcu_preempt kthread timer wakeup didn't happen for 10588 jiffies! g49205 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=28508 rcu: rcu_preempt kthread starved for 10589 jiffies! g49205 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:I stack:27784 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1190/0x5de0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:7058 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2285 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 1300 Comm: aoe_tx0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:do_raw_spin_lock+0x1ce/0x2b0 kernel/locking/spinlock_debug.c:119 Code: ff df 4c 89 63 10 48 c7 44 05 00 00 00 00 00 48 8b 44 24 60 65 48 2b 05 38 9c 3e 12 0f 85 cb 00 00 00 48 83 c4 68 5b 5d 41 5c <41> 5d 41 5e c3 cc cc cc cc 48 c7 c2 08 62 42 8e 89 44 24 28 48 b9 RSP: 0018:ffffc90004a5f958 EFLAGS: 00000092 RAX: 0000000000000000 RBX: ffffffff9b115ba0 RCX: ffffffff8198133c RDX: 1ffffffff3622b76 RSI: 0000000000000004 RDI: ffffc90004a5f900 RBP: 0000000000000293 R08: 0000000000000001 R09: fffff5200094bf20 R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000001 R13: ffffffff9b115bb0 R14: 0000000000000001 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8881247b5000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f44879d4f98 CR3: 0000000059c90000 CR4: 00000000003526f0 Call Trace: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline] _raw_spin_lock_irqsave+0x42/0x60 kernel/locking/spinlock.c:162 uart_port_lock_irqsave include/linux/serial_core.h:717 [inline] uart_port_ref_lock drivers/tty/serial/serial_core.c:83 [inline] uart_write+0x13b/0xb30 drivers/tty/serial/serial_core.c:627 handle_tx+0x204/0x630 drivers/net/caif/caif_serial.c:222 __netdev_start_xmit include/linux/netdevice.h:5222 [inline] netdev_start_xmit include/linux/netdevice.h:5231 [inline] xmit_one net/core/dev.c:3839 [inline] dev_hard_start_xmit+0x94/0x740 net/core/dev.c:3855 __dev_queue_xmit+0xa46/0x4490 net/core/dev.c:4725 dev_queue_xmit include/linux/netdevice.h:3361 [inline] tx+0xcc/0x190 drivers/block/aoe/aoenet.c:62 kthread+0x1e4/0x3e0 drivers/block/aoe/aoecmd.c:1241 kthread+0x3c2/0x780 kernel/kthread.c:463 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245