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BUG: KCSAN: data-race in __wb_writeout_add / writeout_period

write to 0xffffffff86efbd90 of 8 bytes by interrupt on cpu 0:
 writeout_period+0xa6/0xe0 mm/page-writeback.c:614
 call_timer_fn+0x37/0x2f0 kernel/time/timer.c:1700
 expire_timers kernel/time/timer.c:1751 [inline]
 __run_timers+0x46c/0x650 kernel/time/timer.c:2022
 run_timer_softirq+0x31/0x40 kernel/time/timer.c:2037
 __do_softirq+0xc4/0x279 kernel/softirq.c:553
 invoke_softirq kernel/softirq.c:427 [inline]
 __irq_exit_rcu kernel/softirq.c:632 [inline]
 irq_exit_rcu+0x3b/0x90 kernel/softirq.c:644
 sysvec_apic_timer_interrupt+0x6d/0x80 arch/x86/kernel/apic/apic.c:1076
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
 arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline]
 acpi_safe_halt+0x20/0x30 drivers/acpi/processor_idle.c:112
 acpi_idle_do_entry+0x19/0x30 drivers/acpi/processor_idle.c:573
 acpi_idle_enter+0x96/0xb0 drivers/acpi/processor_idle.c:707
 cpuidle_enter_state+0xc6/0x260 drivers/cpuidle/cpuidle.c:267
 cpuidle_enter+0x40/0x60 drivers/cpuidle/cpuidle.c:388
 call_cpuidle kernel/sched/idle.c:134 [inline]
 cpuidle_idle_call kernel/sched/idle.c:215 [inline]
 do_idle+0x194/0x230 kernel/sched/idle.c:282
 cpu_startup_entry+0x24/0x30 kernel/sched/idle.c:380
 rest_init+0xf3/0x100 init/main.c:730
 arch_call_rest_init+0x9/0x10 init/main.c:827
 start_kernel+0x57d/0x5d0 init/main.c:1072
 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:555
 x86_64_start_kernel+0x94/0xa0 arch/x86/kernel/head64.c:536
 secondary_startup_64_no_verify+0x167/0x16b

read to 0xffffffff86efbd90 of 8 bytes by task 26 on cpu 1:
 wb_domain_writeout_add mm/page-writeback.c:563 [inline]
 __wb_writeout_add+0x8a/0x1d0 mm/page-writeback.c:584
 __folio_end_writeback+0x21b/0x4a0 mm/page-writeback.c:2963
 folio_end_writeback+0x74/0x1f0 mm/filemap.c:1598
 ext4_finish_bio+0x45c/0x8c0 fs/ext4/page-io.c:145
 ext4_release_io_end+0x8c/0x1e0 fs/ext4/page-io.c:160
 ext4_end_io_end fs/ext4/page-io.c:194 [inline]
 ext4_do_flush_completed_IO fs/ext4/page-io.c:259 [inline]
 ext4_end_io_rsv_work+0x2d3/0x360 fs/ext4/page-io.c:273
 process_one_work kernel/workqueue.c:2630 [inline]
 process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703
 worker_thread+0x525/0x730 kernel/workqueue.c:2784
 kthread+0x1d7/0x210 kernel/kthread.c:388
 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

value changed: 0x0000000100008cc1 -> 0x0000000100008ded

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 26 Comm: kworker/u4:1 Not tainted 6.7.0-rc1-syzkaller-00012-g9bacdd8996c7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
Workqueue: ext4-rsv-conversion ext4_end_io_rsv_work
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