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WARNING: CPU: 0 PID: 17299 at kernel/rcu/tree_stall.h:1001 rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:993
Modules linked in:
CPU: 0 PID: 17299 Comm: syz.1.3606 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:1001
Code: ff ff ff 48 c7 c7 a0 64 33 97 be 04 00 00 00 e8 6a 26 6e 00 48 89 df b8 01 00 00 00 87 05 cc 93 c1 15 85 c0 0f 85 19 ff ff ff <0f> 0b 48 81 ff 00 70 13 8d 74 47 48 c7 c0 ec ab 8c 8e 48 c1 e8 03
RSP: 0018:ffffc90000007bb8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffffffff8d137000 RCX: ffffffff8171d0c6
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8d137000
RBP: ffffc90000007e30 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff2e66c94 R12: 0000000000002904
R13: 1ffff92000000f94 R14: 0000000000000a02 R15: dffffc0000000000
FS: 00007fef31ed86c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000bbdffc CR3: 000000002fee1000 CR4: 00000000003506f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000002
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
rcu_core+0x5ec/0x17f0 kernel/rcu/tree.c:2462
handle_softirqs+0x27d/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:lock_acquire+0x208/0x420 kernel/locking/lockdep.c:5758
Code: f7 84 24 80 00 00 00 00 02 00 00 43 c6 44 3c 04 f8 0f 85 f0 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 3c 00 00 00 00 43 c7 44 3c 08 00 00 00 00 65 48 8b 04 25
RSP: 0018:ffffc900046dfb80 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 29ed2e0e710b2000
RDX: 0000000000000000 RSI: ffffffff8acadd60 RDI: ffffffff8b1d32e0
RBP: ffffc900046dfc88 R08: dffffc0000000000 R09: 1ffffffff223daa6
R10: dffffc0000000000 R11: fffffbfff223daa7 R12: 1ffff920008dbf7c
R13: ffff88802e66c420 R14: 0000000000000246 R15: dffffc0000000000
__might_fault+0xc6/0x120 mm/memory.c:5968
_copy_from_user+0x2a/0xe0 lib/usercopy.c:14
copy_from_user include/linux/uaccess.h:183 [inline]
restore_sigcontext arch/x86/kernel/signal_64.c:59 [inline]
__ia32_sys_rt_sigreturn+0x2e1/0x850 arch/x86/kernel/signal_64.c:266
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fef30f3f459
Code: 11 06 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 0c 25
RSP: 002b:00007fef31ed7ac0 EFLAGS: 00000202 ORIG_RAX: 000000000000000f
RAX: ffffffffffffffda RBX: 00007fef31225fa0 RCX: 00007fef30f3f459
RDX: 00007fef31ed7ac0 RSI: 00007fef31ed7bf0 RDI: 0000000000000021
RBP: 00007fef31035024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007fef31226038 R14: 00007fef31225fa0 R15: 00007fff36992518
----------------
Code disassembly (best guess):
0: f7 84 24 80 00 00 00 testl $0x200,0x80(%rsp)
7: 00 02 00 00
b: 43 c6 44 3c 04 f8 movb $0xf8,0x4(%r12,%r15,1)
11: 0f 85 f0 00 00 00 jne 0x107
17: 41 f7 c6 00 02 00 00 test $0x200,%r14d
1e: 74 01 je 0x21
20: fb sti
21: 48 c7 44 24 60 0e 36 movq $0x45e0360e,0x60(%rsp)
28: e0 45
* 2a: 4b c7 04 3c 00 00 00 movq $0x0,(%r12,%r15,1) <-- trapping instruction
31: 00
32: 43 c7 44 3c 08 00 00 movl $0x0,0x8(%r12,%r15,1)
39: 00 00
3b: 65 gs
3c: 48 rex.W
3d: 8b .byte 0x8b
3e: 04 25 add $0x25,%al