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WARNING: CPU: 2 PID: 16964 at kernel/rcu/tree_stall.h:824 rcu_check_gp_start_stall.part.0+0x325/0x4b0 kernel/rcu/tree_stall.h:816
Modules linked in:
CPU: 2 PID: 16964 Comm: syz-executor.2 Not tainted 5.12.0-rc5-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
RIP: 0010:rcu_check_gp_start_stall.part.0+0x325/0x4b0 kernel/rcu/tree_stall.h:824
Code: 0f 88 fa 00 00 00 be 04 00 00 00 48 c7 c7 20 65 e2 8f e8 0e 46 57 00 b8 01 00 00 00 87 05 13 0c 82 0e 85 c0 0f 85 c9 00 00 00 <0f> 0b 48 81 fd 00 c9 f7 8b 48 c7 c3 0c 49 c5 8d 74 58 48 b8 00 00
RSP: 0018:ffffc90000550e50 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 000000010000a851 RCX: ffffffff81605902
RDX: fffffbfff1fc4ca4 RSI: 0000000000000004 RDI: ffffffff8fe26520
RBP: ffffffff8bf7c900 R08: 0000000000000001 R09: 0000000000000003
R10: fffffbfff1fc4ca4 R11: ffffffff8bf7c940 R12: 1ffffffff1781e30
R13: 0000000000000246 R14: ffff88802cc35fd2 R15: ffff88802cc36058
FS:  0000000000000000(0000) GS:ffff88802cc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000c0077509c8 CR3: 000000000bc8e000 CR4: 0000000000150ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 rcu_check_gp_start_stall kernel/rcu/tree_stall.h:787 [inline]
 rcu_core+0x4ec/0x12f0 kernel/rcu/tree.c:2789
 __do_softirq+0x29b/0x9f6 kernel/softirq.c:345
 invoke_softirq kernel/softirq.c:221 [inline]
 __irq_exit_rcu kernel/softirq.c:422 [inline]
 irq_exit_rcu+0x134/0x200 kernel/softirq.c:434
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1100
 </IRQ>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:632
RIP: 0010:schedule_debug kernel/sched/core.c:4821 [inline]
RIP: 0010:__schedule+0x12f/0x21b0 kernel/sched/core.c:4967
Code: 03 80 3c 02 00 0f 85 0f 1b 00 00 48 b8 00 00 00 00 00 fc ff df 4d 8b 7d 20 4c 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 d8 1b 00 00 <49> 81 3f 9d 6e ac 57 0f 85 55 20 00 00 49 8d 45 18 84 db 48 89 85
RSP: 0018:ffffc90000c47850 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: 1ffff92000188f12
RDX: 1ffff92000188000 RSI: 0000000000000001 RDI: ffff88801a43d4e0
RBP: ffffc90000c47918 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff8179e0a8 R11: 0000000000000000 R12: ffff88802cc35180
R13: ffff88801a43d4c0 R14: 0000000000035180 R15: ffffc90000c40000
 preempt_schedule_irq+0x4e/0x90 kernel/sched/core.c:5530
 irqentry_exit_cond_resched kernel/entry/common.c:392 [inline]
 irqentry_exit_cond_resched kernel/entry/common.c:384 [inline]
 irqentry_exit+0x7a/0xa0 kernel/entry/common.c:428
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:632
RIP: 0010:memset_erms+0x9/0x10 arch/x86/lib/memset_64.S:64
Code: c1 e9 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 <f3> aa 4c 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01
RSP: 0018:ffffc90000c479f0 EFLAGS: 00010206
RAX: dffffc00000000f8 RBX: 0000000000000000 RCX: 0000000000039200
RDX: 0000000000040000 RSI: 00000000000000f8 RDI: fffff5200560a000
RBP: ffff888012a26680 R08: 00001ffffffffffe R09: fffff52005603200
R10: ffffffff81ad7916 R11: 00000000ffff8000 R12: ffff888012a26688
R13: ffff888012a26698 R14: 0000000000200000 R15: 0000000000200000
 __vunmap+0x34a/0xb60 mm/vmalloc.c:2275
 __vfree+0x3c/0xd0 mm/vmalloc.c:2333
 vfree+0x5a/0x90 mm/vmalloc.c:2364
 kcov_put kernel/kcov.c:408 [inline]
 kcov_put+0x26/0x40 kernel/kcov.c:404
 kcov_close+0xc/0x10 kernel/kcov.c:510
 __fput+0x288/0x920 fs/file_table.c:280
 task_work_run+0xdd/0x1a0 kernel/task_work.c:140
 exit_task_work include/linux/task_work.h:30 [inline]
 do_exit+0xbfc/0x2a60 kernel/exit.c:825
 do_group_exit+0x125/0x310 kernel/exit.c:922
 get_signal+0x47f/0x2150 kernel/signal.c:2781
 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:789
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:301
 __do_fast_syscall_32+0x62/0x90 arch/x86/entry/common.c:143
 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:165
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7f6c549
Code: Unable to access opcode bytes at RIP 0xf7f6c51f.
RSP: 002b:00000000f55455fc EFLAGS: 00000296 ORIG_RAX: 0000000000000150
RAX: 0000000000000004 RBX: 0000000020000100 RCX: 0000000000000000
RDX: 00000000ffffffff RSI: 00000000ffffffff RDI: 0000000000000001
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000