============================= WARNING: suspicious RCU usage syzkaller #0 Tainted: G L ----------------------------- 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.4.2349/14390: #0: ffffffff8e7e50b8 (rcu_tasks_trace_srcu_struct){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:305 [inline] #0: ffffffff8e7e50b8 (rcu_tasks_trace_srcu_struct){....}-{0:0}, at: rcu_read_lock_tasks_trace include/linux/rcupdate_trace.h:59 [inline] #0: ffffffff8e7e50b8 (rcu_tasks_trace_srcu_struct){....}-{0:0}, at: __bpf_prog_test_run_raw_tp+0x1ac/0xa20 net/bpf/test_run.c:756 stack backtrace: CPU: 0 UID: 0 PID: 14390 Comm: syz.4.2349 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 lockdep_rcu_suspicious.cold+0x4f/0xb1 kernel/locking/lockdep.c:6876 get_callchain_entry+0x278/0x3f0 kernel/events/callchain.c:163 get_perf_callchain+0x2d6/0x9c0 kernel/events/callchain.c:231 __bpf_get_stack+0x531/0xa90 kernel/bpf/stackmap.c:730 ____bpf_get_stack kernel/bpf/stackmap.c:775 [inline] bpf_get_stack+0x32/0x40 kernel/bpf/stackmap.c:772 ____bpf_get_stack_raw_tp kernel/trace/bpf_trace.c:1692 [inline] bpf_get_stack_raw_tp+0x1dd/0x280 kernel/trace/bpf_trace.c:1682 bpf_prog_42db8cfdf50901c9+0x46/0x4e bpf_dispatcher_nop_func include/linux/bpf.h:1454 [inline] __bpf_prog_run include/linux/filter.h:723 [inline] bpf_prog_run include/linux/filter.h:730 [inline] __bpf_prog_test_run_raw_tp+0x347/0xa20 net/bpf/test_run.c:767 bpf_prog_test_run_raw_tp+0x566/0x7d0 net/bpf/test_run.c:824 bpf_prog_test_run kernel/bpf/syscall.c:4859 [inline] __sys_bpf+0x2a12/0x4e80 kernel/bpf/syscall.c:6436 __do_sys_bpf kernel/bpf/syscall.c:6537 [inline] __se_sys_bpf kernel/bpf/syscall.c:6534 [inline] __ia32_sys_bpf+0xcc/0x170 kernel/bpf/syscall.c:6534 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0xe7/0x970 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf6feefec Code: Unable to access opcode bytes at 0xf6feefc2. RSP: 002b:00000000f53dd50c EFLAGS: 00000292 ORIG_RAX: 0000000000000165 RAX: ffffffffffffffda RBX: 000000000000000a RCX: 0000000080000740 RDX: 0000000000000010 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000