=============================
WARNING: suspicious RCU usage
syzkaller #0 Not tainted
-----------------------------
kernel/events/callchain.c:163 suspicious rcu_dereference_check() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
1 lock held by syz.0.131/4801:
 #0: ffffffff885df780 (rcu_read_lock_trace){....}-{0:0}, at: rcu_read_lock_trace include/linux/rcupdate_trace.h:53 [inline]
 #0: ffffffff885df780 (rcu_read_lock_trace){....}-{0:0}, at: bpf_prog_test_run_syscall+0x2fe/0xcaa net/bpf/test_run.c:1572

stack backtrace:
CPU: 1 UID: 0 PID: 4801 Comm: syz.0.131 Not tainted syzkaller #0 PREEMPT 
Hardware name: riscv-virtio,qemu (DT)
Call Trace:
[<ffffffff8007941a>] dump_backtrace+0x2e/0x3c arch/riscv/kernel/stacktrace.c:132
[<ffffffff8000329a>] show_stack+0x30/0x3c arch/riscv/kernel/stacktrace.c:138
[<ffffffff80060bf4>] __dump_stack lib/dump_stack.c:94 [inline]
[<ffffffff80060bf4>] dump_stack_lvl+0x12a/0x1a2 lib/dump_stack.c:120
[<ffffffff80060c88>] dump_stack+0x1c/0x24 lib/dump_stack.c:129
[<ffffffff802d97e8>] lockdep_rcu_suspicious+0x196/0x26a kernel/locking/lockdep.c:6876
[<ffffffff8083933c>] get_callchain_entry+0x2da/0x448 kernel/events/callchain.c:163
[<ffffffff80839978>] get_perf_callchain+0x3fa/0x772 kernel/events/callchain.c:231
[<ffffffff8079e808>] __bpf_get_stack+0x490/0xa26 kernel/bpf/stackmap.c:454
[<ffffffff8079edd2>] ____bpf_get_stack kernel/bpf/stackmap.c:499 [inline]
[<ffffffff8079edd2>] bpf_get_stack+0x34/0x44 kernel/bpf/stackmap.c:496
[<ffffffff8059f86e>] ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1653 [inline]
[<ffffffff8059f86e>] bpf_get_stack_raw_tp+0xde/0x112 kernel/trace/bpf_trace.c:1643
[<ffffffff780027e2>] bpf_prog_e8e6327ccf46c9a7+0x4a/0x5c
[<ffffffff85661b38>] bpf_dispatcher_nop_func include/linux/bpf.h:1350 [inline]
[<ffffffff85661b38>] __bpf_prog_run include/linux/filter.h:712 [inline]
[<ffffffff85661b38>] bpf_prog_run include/linux/filter.h:728 [inline]
[<ffffffff85661b38>] bpf_prog_run_pin_on_cpu include/linux/filter.h:745 [inline]
[<ffffffff85661b38>] bpf_prog_test_run_syscall+0x678/0xcaa net/bpf/test_run.c:1573
[<ffffffff80600e14>] bpf_prog_test_run kernel/bpf/syscall.c:4673 [inline]
[<ffffffff80600e14>] __sys_bpf+0x1e96/0x4492 kernel/bpf/syscall.c:6152
[<ffffffff8060420e>] __do_sys_bpf kernel/bpf/syscall.c:6244 [inline]
[<ffffffff8060420e>] __se_sys_bpf kernel/bpf/syscall.c:6242 [inline]
[<ffffffff8060420e>] __riscv_sys_bpf+0x70/0xce kernel/bpf/syscall.c:6242
[<ffffffff800770dc>] syscall_handler+0x94/0x118 arch/riscv/include/asm/syscall.h:112
[<ffffffff8647a47e>] do_trap_ecall_u+0x39e/0x53a arch/riscv/kernel/traps.c:343
[<ffffffff864a3d82>] handle_exception+0x146/0x152 arch/riscv/kernel/entry.S:198