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WARNING: CPU: 0 PID: 5306 at kernel/rcu/tree_stall.h:970 rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:962
Modules linked in:
CPU: 0 PID: 5306 Comm: syz.2.214 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:rcu_check_gp_start_stall+0x2dc/0x460 kernel/rcu/tree_stall.h:970
Code: ff ff ff 48 c7 c7 20 ef c3 96 be 04 00 00 00 e8 3a 53 66 00 48 89 df b8 01 00 00 00 87 05 4c e3 56 15 85 c0 0f 85 19 ff ff ff <0f> 0b 48 81 ff 80 2b b3 8c 74 47 48 c7 c0 e4 f7 1f 8e 48 c1 e8 03
RSP: 0018:ffffc90000007b78 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffffffff8cb32b80 RCX: ffffffff816d0bc6
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8cb32b80
RBP: ffffc90000007df0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff2d87de4 R12: 0000000000002904
R13: dffffc0000000000 R14: 0000000000000a06 R15: dffffc0000000000
FS: 00007fe5fba9e6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe5fba7cff8 CR3: 0000000028387000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
rcu_core+0x60b/0x1740 kernel/rcu/tree.c:2552
handle_softirqs+0x2a1/0x930 kernel/softirq.c:596
__do_softirq kernel/softirq.c:630 [inline]
invoke_softirq kernel/softirq.c:470 [inline]
__irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679
irq_exit_rcu+0x5/0x20 kernel/softirq.c:691
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:lock_acquire+0x225/0x4a0 kernel/locking/lockdep.c:5666
Code: f7 84 24 80 00 00 00 00 02 00 00 43 c6 44 3d 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 44 3d 00 00 00 00 00 43 c7 44 3d 08 00 00 00 00 65 48 8b 04
RSP: 0018:ffffc9000df37be0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 79e1c9707865cd00
RDX: 0000000000000000 RSI: ffffffff8a8c23a0 RDI: ffffffff8adf0c20
RBP: ffffc9000df37d00 R08: dffffc0000000000 R09: 1ffffffff215e64e
R10: dffffc0000000000 R11: fffffbfff215e64f R12: 0000000000000000
R13: 1ffff92001be6f88 R14: 0000000000000246 R15: dffffc0000000000
__might_fault+0xc2/0x120 mm/memory.c:5850
_copy_from_user+0x27/0x170 lib/usercopy.c:14
copy_from_user include/linux/uaccess.h:161 [inline]
do_fcntl+0x509/0x1270 fs/fcntl.c:353
__do_sys_fcntl fs/fcntl.c:446 [inline]
__se_sys_fcntl+0xc9/0x190 fs/fcntl.c:431
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe5fab9aeb9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe5fba9e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000048
RAX: ffffffffffffffda RBX: 00007fe5fae15fa0 RCX: 00007fe5fab9aeb9
RDX: 0000200000000280 RSI: 0000000000000026 RDI: 0000000000000003
RBP: 00007fe5fac08c1f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe5fae16038 R14: 00007fe5fae15fa0 R15: 00007ffe818768e8
----------------
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 3d 04 f8 movb $0xf8,0x4(%r13,%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 44 3d 00 00 00 movq $0x0,0x0(%r13,%r15,1) <-- trapping instruction
31: 00 00
33: 43 c7 44 3d 08 00 00 movl $0x0,0x8(%r13,%r15,1)
3a: 00 00
3c: 65 gs
3d: 48 rex.W
3e: 8b .byte 0x8b
3f: 04 .byte 0x4