==================================================================
BUG: KCSAN: data-race in __bpf_get_stackid / __bpf_get_stackid

write to 0xffff88810a18baa8 of 4 bytes by interrupt on cpu 0:
 __bpf_get_stackid+0x76b/0x800 kernel/bpf/stackmap.c:291
 ____bpf_get_stackid kernel/bpf/stackmap.c:324 [inline]
 bpf_get_stackid+0xee/0x120 kernel/bpf/stackmap.c:300
 ____bpf_get_stackid_raw_tp kernel/trace/bpf_trace.c:1811 [inline]
 bpf_get_stackid_raw_tp+0xf6/0x120 kernel/trace/bpf_trace.c:1800
 bpf_prog_e6fc920cfeff8120+0x2a/0x32
 bpf_dispatcher_nop_func include/linux/bpf.h:1322 [inline]
 __bpf_prog_run include/linux/filter.h:718 [inline]
 bpf_prog_run include/linux/filter.h:725 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2258 [inline]
 bpf_trace_run2+0x107/0x1c0 kernel/trace/bpf_trace.c:2299
 __do_trace_kfree include/trace/events/kmem.h:94 [inline]
 trace_kfree include/trace/events/kmem.h:94 [inline]
 kfree+0x27b/0x320 mm/slub.c:4829
 shmem_free_in_core_inode+0x50/0x80 mm/shmem.c:5159
 i_callback+0x36/0x70 fs/inode.c:325
 rcu_do_batch kernel/rcu/tree.c:2576 [inline]
 rcu_core+0x5a5/0xc00 kernel/rcu/tree.c:2832
 rcu_core_si+0xd/0x20 kernel/rcu/tree.c:2849
 handle_softirqs+0xb7/0x290 kernel/softirq.c:579
 run_ksoftirqd+0x1c/0x30 kernel/softirq.c:968
 smpboot_thread_fn+0x328/0x530 kernel/smpboot.c:164
 kthread+0x489/0x510 kernel/kthread.c:464
 ret_from_fork+0xda/0x150 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff88810a18baa8 of 4 bytes by task 2135 on cpu 1:
 __bpf_get_stackid+0x287/0x800 kernel/bpf/stackmap.c:249
 ____bpf_get_stackid kernel/bpf/stackmap.c:324 [inline]
 bpf_get_stackid+0xee/0x120 kernel/bpf/stackmap.c:300
 ____bpf_get_stackid_raw_tp kernel/trace/bpf_trace.c:1811 [inline]
 bpf_get_stackid_raw_tp+0xf6/0x120 kernel/trace/bpf_trace.c:1800
 bpf_prog_e6fc920cfeff8120+0x2a/0x32
 bpf_dispatcher_nop_func include/linux/bpf.h:1322 [inline]
 __bpf_prog_run include/linux/filter.h:718 [inline]
 bpf_prog_run include/linux/filter.h:725 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2258 [inline]
 bpf_trace_run2+0x107/0x1c0 kernel/trace/bpf_trace.c:2299
 __do_trace_kfree include/trace/events/kmem.h:94 [inline]
 trace_kfree include/trace/events/kmem.h:94 [inline]
 kfree+0x27b/0x320 mm/slub.c:4829
 skb_kfree_head net/core/skbuff.c:1048 [inline]
 skb_free_head+0xb8/0x150 net/core/skbuff.c:1060
 skb_release_data+0x33b/0x370 net/core/skbuff.c:1087
 skb_release_all net/core/skbuff.c:1152 [inline]
 __kfree_skb+0x44/0x150 net/core/skbuff.c:1166
 consume_skb+0x49/0x150 net/core/skbuff.c:1398
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline]
 nsim_dev_trap_report_work+0x533/0x630 drivers/net/netdevsim/dev.c:851
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x4cb/0x9d0 kernel/workqueue.c:3321
 worker_thread+0x582/0x770 kernel/workqueue.c:3402
 kthread+0x489/0x510 kernel/kthread.c:464
 ret_from_fork+0xda/0x150 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0xc0b24379 -> 0x628911eb

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 2135 Comm: kworker/u8:8 Not tainted 6.16.0-rc7-syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_unbound nsim_dev_trap_report_work
==================================================================