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WARNING: CPU: 0 PID: 12 at kernel/rcu/tree_stall.h:770 rcu_check_gp_start_stall.part.0+0x1b2/0x2b0 kernel/rcu/tree_stall.h:762
Modules linked in:
CPU: 0 PID: 12 Comm: ksoftirqd/0 Not tainted 5.11.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:rcu_check_gp_start_stall.part.0+0x1b2/0x2b0 kernel/rcu/tree_stall.h:770
Code: 78 0a 48 01 c3 48 39 da 78 5d be 04 00 00 00 48 c7 c7 a0 53 bf 8f e8 ed 3e 56 00 b8 01 00 00 00 87 05 12 e1 5f 0e 85 c0 75 34 <0f> 0b 48 81 fd 40 c0 d7 8b 74 0c 48 c7 c7 40 c0 d7 8b e8 a7 93 9d
RSP: 0018:ffffc90000d17cf0 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 00000000fffffdd4 RCX: ffffffff815f7283
RDX: fffffbfff1f7ea74 RSI: 0000000000000004 RDI: ffffffff8fbf53a0
RBP: ffffffff8bd7c040 R08: 0000000000000001 R09: 0000000000000003
R10: fffffbfff1f7ea74 R11: ffffffff8bd7c088 R12: 1ffffffff1741e30
R13: 0000000000000246 R14: ffff8880b9c35a92 R15: ffff8880b9c35b18
FS:  0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055fd2297f018 CR3: 000000000ba8e000 CR4: 0000000000350ef0
Call Trace:
 rcu_check_gp_start_stall kernel/rcu/tree_stall.h:733 [inline]
 rcu_core+0x3b1/0xf00 kernel/rcu/tree.c:2718
 __do_softirq+0x29b/0x9f6 kernel/softirq.c:343
 run_ksoftirqd kernel/softirq.c:650 [inline]
 run_ksoftirqd+0x2d/0x50 kernel/softirq.c:642
 smpboot_thread_fn+0x655/0x9e0 kernel/smpboot.c:165
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296