=============================
WARNING: suspicious RCU usage
6.9.0-rc4-next-20240418-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/0/16:
#0: ffffffff8e333ae0 (rcu_read_lock_sched){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
#0: ffffffff8e333ae0 (rcu_read_lock_sched){....}-{1:2}, at: rcu_read_lock_sched include/linux/rcupdate.h:933 [inline]
#0: ffffffff8e333ae0 (rcu_read_lock_sched){....}-{1:2}, at: pfn_valid include/linux/mmzone.h:2022 [inline]
#0: ffffffff8e333ae0 (rcu_read_lock_sched){....}-{1:2}, at: __virt_addr_valid+0x183/0x520 arch/x86/mm/physaddr.c:65
stack backtrace:
CPU: 0 PID: 16 Comm: ksoftirqd/0 Not tainted 6.9.0-rc4-next-20240418-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_is_watching+0x1c/0xb0 kernel/rcu/tree.c:725
Code: 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 3d 87 7e e8 2b ae 09 0a 89 c3 83 f8 08 73 7a <49> bf 00 00 00 00 00 fc ff df 4c 8d 34 dd e0 49 d9 8d 4c 89 f0 48
RSP: 0018:ffffc90000157900 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8172d8f0
RDX: 0000000000000000 RSI: ffffffff8c1f8ba0 RDI: ffffffff8c1f8b60
RBP: ffffc90000157a48 R08: ffffffff8fabdf2f R09: 1ffffffff1f57be5
R10: dffffc0000000000 R11: fffffbfff1f57be6 R12: 1ffff9200002af30
R13: ffffffff81424043 R14: ffffffff81424043 R15: dffffc0000000000
trace_lock_release include/trace/events/lock.h:69 [inline]
lock_release+0xbf/0x9f0 kernel/locking/lockdep.c:5765
rcu_lock_release include/linux/rcupdate.h:339 [inline]
rcu_read_unlock_sched include/linux/rcupdate.h:954 [inline]
pfn_valid include/linux/mmzone.h:2032 [inline]
__virt_addr_valid+0x41e/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:3102 [inline]
call_rcu+0x167/0xa70 kernel/rcu/tree.c:3206
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
----------------
Code disassembly (best guess):
0: 90 nop
1: 90 nop
2: 90 nop
3: 90 nop
4: 90 nop
5: 90 nop
6: 90 nop
7: 90 nop
8: 90 nop
9: 90 nop
a: 90 nop
b: 90 nop
c: 90 nop
d: 90 nop
e: f3 0f 1e fa endbr64
12: 41 57 push %r15
14: 41 56 push %r14
16: 53 push %rbx
17: 65 ff 05 08 3d 87 7e incl %gs:0x7e873d08(%rip) # 0x7e873d26
1e: e8 2b ae 09 0a call 0xa09ae4e
23: 89 c3 mov %eax,%ebx
25: 83 f8 08 cmp $0x8,%eax
28: 73 7a jae 0xa4
* 2a: 49 bf 00 00 00 00 00 movabs $0xdffffc0000000000,%r15 <-- trapping instruction
31: fc ff df
34: 4c 8d 34 dd e0 49 d9 lea -0x7226b620(,%rbx,8),%r14
3b: 8d
3c: 4c 89 f0 mov %r14,%rax
3f: 48 rex.W