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BUG: KCSAN: data-race in do_select / pollwake

write to 0xffffc9000288ba00 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+0x66/0xb0 kernel/sched/wait.c:127
 ep_poll_safewake fs/eventpoll.c:657 [inline]
 ep_poll_callback+0x4fe/0x630 fs/eventpoll.c:1418
 __wake_up_common kernel/sched/wait.c:89 [inline]
 __wake_up_common_lock kernel/sched/wait.c:106 [inline]
 __wake_up+0x66/0xb0 kernel/sched/wait.c:127
 rtc_handle_legacy_irq drivers/rtc/interface.c:627 [inline]
 rtc_pie_update_irq+0xbd/0xf0 drivers/rtc/interface.c:672
 __run_hrtimer kernel/time/hrtimer.c:1761 [inline]
 __hrtimer_run_queues+0x20c/0x5a0 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x21a/0x460 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x5c/0x1d0 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0x6f/0x80 arch/x86/kernel/apic/apic.c:1049
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
 native_ptep_get_and_clear arch/x86/include/asm/pgtable_64.h:-1 [inline]
 ptep_get_and_clear arch/x86/include/asm/pgtable.h:1320 [inline]
 ptep_get_and_clear_full arch/x86/include/asm/pgtable.h:1339 [inline]
 clear_full_ptes include/linux/pgtable.h:751 [inline]
 zap_present_folio_ptes mm/memory.c:1514 [inline]
 zap_present_ptes mm/memory.c:1586 [inline]
 do_zap_pte_range mm/memory.c:1687 [inline]
 zap_pte_range mm/memory.c:1731 [inline]
 zap_pmd_range mm/memory.c:1823 [inline]
 zap_pud_range mm/memory.c:1852 [inline]
 zap_p4d_range mm/memory.c:1873 [inline]
 unmap_page_range+0xbaf/0x27b0 mm/memory.c:1894
 unmap_single_vma+0x138/0x1d0 mm/memory.c:1940
 unmap_vmas+0x18a/0x2b0 mm/memory.c:1984
 exit_mmap+0x1b0/0x6c0 mm/mmap.c:1284
 __mmput+0x28/0x1c0 kernel/fork.c:1380
 mmput+0x40/0x50 kernel/fork.c:1402
 exit_mm+0xe4/0x190 kernel/exit.c:589
 do_exit+0x55f/0x17c0 kernel/exit.c:940
 do_group_exit+0x139/0x140 kernel/exit.c:1102
 __do_sys_exit_group kernel/exit.c:1113 [inline]
 __se_sys_exit_group kernel/exit.c:1111 [inline]
 __x64_sys_exit_group+0x1f/0x20 kernel/exit.c:1111
 x64_sys_call+0x2fa4/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:232
 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 0xffffc9000288ba00 of 4 bytes by task 3419 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: 3419 Comm: syz.9.18664 Tainted: G        W           6.15.0-rc7-syzkaller-00002-gb36ddb9210e6 #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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