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BUG: KCSAN: data-race in __bpf_get_stackid / __bpf_get_stackid

write to 0xffffc90001deb65c of 4 bytes by task 6663 on cpu 0:
 __bpf_get_stackid+0x77a/0x800 kernel/bpf/stackmap.c:292
 ____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:1810 [inline]
 bpf_get_stackid_raw_tp+0xf6/0x120 kernel/trace/bpf_trace.c:1799
 bpf_prog_e6fc920cfeff8120+0x2a/0x32
 bpf_dispatcher_nop_func include/linux/bpf.h:1332 [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:2257 [inline]
 bpf_trace_run4+0x117/0x1d0 kernel/trace/bpf_trace.c:2300
 __traceiter_sched_switch+0x3c/0x60 include/trace/events/sched.h:220
 __do_trace_sched_switch include/trace/events/sched.h:220 [inline]
 trace_sched_switch include/trace/events/sched.h:220 [inline]
 __schedule+0xa17/0xb30 kernel/sched/core.c:6958
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x5f/0xd0 kernel/sched/core.c:7058
 io_schedule+0x3f/0x60 kernel/sched/core.c:7903
 bit_wait_io+0xc/0x60 kernel/sched/wait_bit.c:250
 __wait_on_bit+0x45/0xe0 kernel/sched/wait_bit.c:52
 out_of_line_wait_on_bit+0x8d/0xb0 kernel/sched/wait_bit.c:67
 wait_on_bit_io include/linux/wait_bit.h:105 [inline]
 __wait_on_buffer fs/buffer.c:123 [inline]
 wait_on_buffer include/linux/buffer_head.h:420 [inline]
 __bread_slow fs/buffer.c:1273 [inline]
 __bread_gfp+0x1c6/0x250 fs/buffer.c:1518
 sb_bread include/linux/buffer_head.h:346 [inline]
 isofs_fill_super+0x3dc/0x1270 fs/isofs/inode.c:627
 get_tree_bdev_flags+0x291/0x300 fs/super.c:1692
 get_tree_bdev+0x1f/0x30 fs/super.c:1715
 isofs_get_tree+0x1c/0x30 fs/isofs/inode.c:1533
 vfs_get_tree+0x54/0x1d0 fs/super.c:1815
 do_new_mount+0x207/0x5e0 fs/namespace.c:3808
 path_mount+0x4a4/0xb20 fs/namespace.c:4123
 do_mount fs/namespace.c:4136 [inline]
 __do_sys_mount fs/namespace.c:4347 [inline]
 __se_sys_mount+0x28f/0x2e0 fs/namespace.c:4324
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4324
 x64_sys_call+0x2b4d/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffc90001deb65c of 4 bytes by task 15 on cpu 1:
 __bpf_get_stackid+0x33a/0x800 kernel/bpf/stackmap.c:278
 ____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:1810 [inline]
 bpf_get_stackid_raw_tp+0xf6/0x120 kernel/trace/bpf_trace.c:1799
 bpf_prog_e6fc920cfeff8120+0x2a/0x32
 bpf_dispatcher_nop_func include/linux/bpf.h:1332 [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:2257 [inline]
 bpf_trace_run4+0x117/0x1d0 kernel/trace/bpf_trace.c:2300
 __traceiter_sched_switch+0x3c/0x60 include/trace/events/sched.h:220
 __do_trace_sched_switch include/trace/events/sched.h:220 [inline]
 trace_sched_switch include/trace/events/sched.h:220 [inline]
 __schedule+0xa17/0xb30 kernel/sched/core.c:6958
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x5f/0xd0 kernel/sched/core.c:7058
 schedule_timeout+0xb7/0x170 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x2a5/0xbc0 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x28/0x250 kernel/rcu/tree.c:2285
 kthread+0x486/0x510 kernel/kthread.c:463
 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: 0x0000000c -> 0x00000017

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 15 Comm: rcu_preempt Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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