============================= WARNING: suspicious RCU usage 6.9.0-rc5-next-20240426-syzkaller #0 Not tainted ----------------------------- kernel/rcu/tree.c:276 Illegal rcu_softirq_qs() in RCU read-side critical section! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by ksoftirqd/1/24: #0: ffffffff8e333b20 (rcu_read_lock_sched){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8e333b20 (rcu_read_lock_sched){....}-{1:2}, at: rcu_read_lock_sched include/linux/rcupdate.h:933 [inline] #0: ffffffff8e333b20 (rcu_read_lock_sched){....}-{1:2}, at: pfn_valid include/linux/mmzone.h:2022 [inline] #0: ffffffff8e333b20 (rcu_read_lock_sched){....}-{1:2}, at: __virt_addr_valid+0x183/0x520 arch/x86/mm/physaddr.c:65 stack backtrace: CPU: 1 PID: 24 Comm: ksoftirqd/1 Not tainted 6.9.0-rc5-next-20240426-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 lockdep_rcu_suspicious+0x221/0x340 kernel/locking/lockdep.c:6712 rcu_softirq_qs+0xd9/0x370 kernel/rcu/tree.c:273 __do_softirq+0x5fd/0x980 kernel/softirq.c:568 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633 irq_exit_rcu+0x9/0x30 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline] RIP: 0010:rcu_is_watching+0x10/0xb0 kernel/rcu/tree.c:725 Code: 0a 0a 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 53 65 ff 05 08 3f 87 7e 7b de 0a 0a 89 c3 83 f8 08 73 7a 49 bf 00 00 00 00 00 fc ff df RSP: 0018:ffffc900001e7a38 EFLAGS: 00000286 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff888017af0000 RDX: ffff888017af0000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffffffff81424147 R09: 1ffffffff25f2cb0 R10: dffffc0000000000 R11: fffffbfff25f2cb1 R12: 00000000151a1778 R13: 1ffff9200003cf64 R14: ffffffff81423f93 R15: ffff88813fff9040 rcu_read_unlock_sched include/linux/rcupdate.h:952 [inline] pfn_valid include/linux/mmzone.h:2032 [inline] __virt_addr_valid+0x340/0x520 arch/x86/mm/physaddr.c:65 kasan_addr_to_slab+0xd/0x80 mm/kasan/common.c:37 __kasan_record_aux_stack+0x11/0xc0 mm/kasan/generic.c:526 __call_rcu_common kernel/rcu/tree.c:3103 [inline] call_rcu+0x167/0xa70 kernel/rcu/tree.c:3207 context_switch kernel/sched/core.c:5411 [inline] __schedule+0x17f0/0x4a50 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6837 smpboot_thread_fn+0x61e/0xa30 kernel/smpboot.c:160 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 vkms_vblank_simulate: vblank timer overrun vkms_vblank_simulate: vblank timer overrun vkms_vblank_simulate: vblank timer overrun ------------[ cut here ]------------ WARNING: CPU: 1 PID: 24 at kernel/kcov.c:870 kcov_remote_start+0x5a2/0x7e0 kernel/kcov.c:870 Modules linked in: CPU: 1 PID: 24 Comm: ksoftirqd/1 Not tainted 6.9.0-rc5-next-20240426-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:kcov_remote_start+0x5a2/0x7e0 kernel/kcov.c:870 Code: 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 0f 85 a6 01 00 00 41 f7 c6 00 02 00 00 0f 84 93 fa ff ff fb e9 8d fa ff ff 90 <0f> 0b 90 e8 96 10 f1 09 89 c0 48 c7 c7 c8 d4 02 00 48 03 3c c5 e0 RSP: 0018:ffffc90000a189c0 EFLAGS: 00010002 RAX: 0000000080010100 RBX: ffff888017af0000 RCX: 0000000000000002 RDX: dffffc0000000000 RSI: ffffffff8bcac4c0 RDI: ffffffff8c1fc4e0 RBP: 0100000000000003 R08: ffffffff92f965f7 R09: 1ffffffff25f2cbe R10: dffffc0000000000 R11: fffffbfff25f2cbf R12: ffffffff81965ede R13: 00000000ffffffb9 R14: 0000000000000006 R15: ffff8880b952d4c8 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c00160b000 CR3: 0000000022b7e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: kcov_remote_start_usb include/linux/kcov.h:53 [inline] kcov_remote_start_usb_softirq include/linux/kcov.h:66 [inline] __usb_hcd_giveback_urb+0x34a/0x530 drivers/usb/core/hcd.c:1647 dummy_timer+0x830/0x45d0 drivers/usb/gadget/udc/dummy_hcd.c:1987 __run_hrtimer kernel/time/hrtimer.c:1687 [inline] __hrtimer_run_queues+0x5a5/0xd50 kernel/time/hrtimer.c:1751 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1813 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x110/0x3f0 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:kcov_remote_start+0x2e/0x7e0 kernel/kcov.c:924 Code: 55 41 57 41 56 41 55 41 54 53 48 83 ec 18 65 48 8b 1c 25 00 d5 03 00 48 b8 00 00 00 00 ff ff ff 00 48 85 c7 74 17 90 0f 0b 90 <48> 83 c4 18 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc 48 89 fd RSP: 0018:ffffc900001e7840 EFLAGS: 00000206 RAX: 9bdab27f123ceb00 RBX: ffff888017af0000 RCX: ffffffff817318da RDX: dffffc0000000000 RSI: ffffffff8bcab340 RDI: ffffffff8c1fc4e0 RBP: ffff8880b952d4c8 R08: ffffffff92f965f7 R09: 1ffffffff25f2cbe R10: dffffc0000000000 R11: fffffbfff25f2cbf R12: 0000000000040000 R13: 0000000000000000 R14: 0000000000000206 R15: ffff88801eba4400 kcov_remote_start_usb include/linux/kcov.h:53 [inline] kcov_remote_start_usb_softirq include/linux/kcov.h:66 [inline] __usb_hcd_giveback_urb+0x34a/0x530 drivers/usb/core/hcd.c:1647 usb_giveback_urb_bh+0x306/0x4e0 drivers/usb/core/hcd.c:1682 process_one_work kernel/workqueue.c:3222 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3303 bh_worker+0x2a5/0x620 kernel/workqueue.c:3563 tasklet_hi_action+0xf/0x90 kernel/softirq.c:812 __do_softirq+0x2c6/0x980 kernel/softirq.c:554 run_ksoftirqd+0xc5/0x130 kernel/softirq.c:924 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 ---------------- Code disassembly (best guess): 0: 0a 0a or (%rdx),%cl 2: 0f 1f 84 00 00 00 00 nopl 0x0(%rax,%rax,1) 9: 00 a: 90 nop b: 90 nop c: 90 nop d: 90 nop e: 90 nop f: 90 nop 10: 90 nop 11: 90 nop 12: 90 nop 13: 90 nop 14: 90 nop 15: 90 nop 16: 90 nop 17: 90 nop 18: 90 nop 19: 90 nop 1a: f3 0f 1e fa endbr64 1e: 41 57 push %r15 20: 41 56 push %r14 22: 53 push %rbx 23: 65 ff 05 08 3f 87 7e incl %gs:0x7e873f08(%rip) # 0x7e873f32 * 2a: e8 7b de 0a 0a call 0xa0adeaa <-- trapping instruction 2f: 89 c3 mov %eax,%ebx 31: 83 f8 08 cmp $0x8,%eax 34: 73 7a jae 0xb0 36: 49 bf 00 00 00 00 00 movabs $0xdffffc0000000000,%r15 3d: fc ff df