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BUG: KCSAN: data-race in do_select / pollwake

write to 0xffffc9000526fa00 of 4 bytes by interrupt on cpu 0:
 __pollwake fs/select.c:195 [inline]
 pollwake+0xb6/0x100 fs/select.c:215
 __wake_up_common kernel/sched/wait.c:89 [inline]
 __wake_up_common_lock kernel/sched/wait.c:106 [inline]
 __wake_up+0x63/0xb0 kernel/sched/wait.c:127
 bpf_ringbuf_notify+0x22/0x30 kernel/bpf/ringbuf.c:155
 irq_work_single kernel/irq_work.c:221 [inline]
 irq_work_run_list kernel/irq_work.c:252 [inline]
 irq_work_run+0xdf/0x2d0 kernel/irq_work.c:261
 __sysvec_irq_work+0x22/0x170 arch/x86/kernel/irq_work.c:22
 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline]
 sysvec_irq_work+0x2f/0x80 arch/x86/kernel/irq_work.c:17
 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:738
 __wrmsr arch/x86/include/asm/msr.h:96 [inline]
 native_write_msr arch/x86/include/asm/msr.h:147 [inline]
 wrmsr arch/x86/include/asm/msr.h:256 [inline]
 native_apic_msr_write+0x3d/0x60 arch/x86/include/asm/apic.h:212
 apic_write arch/x86/include/asm/apic.h:405 [inline]
 x2apic_send_IPI_self+0x10/0x20 arch/x86/kernel/apic/x2apic_phys.c:107
 __apic_send_IPI_self arch/x86/include/asm/apic.h:455 [inline]
 arch_irq_work_raise+0x46/0x50 arch/x86/kernel/irq_work.c:31
 irq_work_raise kernel/irq_work.c:84 [inline]
 __irq_work_queue_local+0x80/0x1b0 kernel/irq_work.c:112
 irq_work_queue+0x70/0x100 kernel/irq_work.c:124
 bpf_ringbuf_commit kernel/bpf/ringbuf.c:-1 [inline]
 ____bpf_ringbuf_discard kernel/bpf/ringbuf.c:525 [inline]
 bpf_ringbuf_discard+0xd3/0xf0 kernel/bpf/ringbuf.c:523
 bpf_prog_fe0ed97373b08409+0x47/0x4b
 bpf_dispatcher_nop_func include/linux/bpf.h:1316 [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:2363 [inline]
 bpf_trace_run3+0x10c/0x1d0 kernel/trace/bpf_trace.c:2405
 __do_trace_kmem_cache_free include/trace/events/kmem.h:114 [inline]
 trace_kmem_cache_free include/trace/events/kmem.h:114 [inline]
 kmem_cache_free+0x246/0x2f0 mm/slub.c:4743
 skb_kfree_head net/core/skbuff.c:1056 [inline]
 skb_free_head net/core/skbuff.c:1070 [inline]
 skb_release_data+0x53b/0x620 net/core/skbuff.c:1097
 skb_release_all net/core/skbuff.c:1162 [inline]
 napi_consume_skb+0xf6/0x210 net/core/skbuff.c:1490
 skb_defer_free_flush net/core/dev.c:6544 [inline]
 net_rx_action+0x25c/0x7b0 net/core/dev.c:7491
 handle_softirqs+0xb7/0x290 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0x3a/0xc0 kernel/softirq.c:680
 common_interrupt+0x83/0x90 arch/x86/kernel/irq.c:285
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
 __sanitizer_cov_trace_pc+0x5d/0x70 kernel/kcov.c:233
 __folio_dup_file_rmap include/linux/rmap.h:557 [inline]
 folio_dup_file_rmap_pte include/linux/rmap.h:596 [inline]
 copy_present_ptes mm/memory.c:1039 [inline]
 copy_pte_range mm/memory.c:1167 [inline]
 copy_pmd_range mm/memory.c:1255 [inline]
 copy_pud_range mm/memory.c:1292 [inline]
 copy_p4d_range mm/memory.c:1316 [inline]
 copy_page_range+0xad9/0x3760 mm/memory.c:1410
 dup_mmap kernel/fork.c:726 [inline]
 dup_mm kernel/fork.c:1734 [inline]
 copy_mm+0xab6/0x1310 kernel/fork.c:1786
 copy_process+0xcf1/0x1f90 kernel/fork.c:2429
 kernel_clone+0x16c/0x5b0 kernel/fork.c:2844
 __do_sys_clone kernel/fork.c:2987 [inline]
 __se_sys_clone kernel/fork.c:2971 [inline]
 __x64_sys_clone+0xe6/0x120 kernel/fork.c:2971
 x64_sys_call+0x2c59/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:57
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffc9000526fa00 of 4 bytes by task 19125 on cpu 1:
 poll_schedule_timeout fs/select.c:240 [inline]
 do_select+0xe41/0xf40 fs/select.c:603
 core_sys_select+0x3b2/0x600 fs/select.c:677
 do_pselect fs/select.c:759 [inline]
 __do_sys_pselect6 fs/select.c:802 [inline]
 __se_sys_pselect6+0x216/0x280 fs/select.c:793
 __x64_sys_pselect6+0x78/0x90 fs/select.c:793
 x64_sys_call+0x1caa/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:271
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 19125 Comm: syz.8.5517 Not tainted 6.15.0-rc5-syzkaller-00032-g0d8d44db295c #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
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