================================================================== BUG: KCSAN: data-race in __wb_writeout_add / writeout_period write to 0xffffffff86ef7d90 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:649 console_flush_all+0x49c/0x6a0 console_unlock+0x7b/0x270 kernel/printk/printk.c:3036 vprintk_emit+0x3a3/0x5d0 kernel/printk/printk.c:2303 vprintk_default+0x26/0x30 kernel/printk/printk.c:2318 vprintk+0x71/0x80 kernel/printk/printk_safe.c:45 _printk+0x7a/0xa0 kernel/printk/printk.c:2328 mnt_warn_timestamp_expiry+0x1bb/0x1f0 fs/namespace.c:2804 do_new_mount_fc fs/namespace.c:3278 [inline] do_new_mount+0x2ee/0x660 fs/namespace.c:3339 path_mount+0x496/0xb30 fs/namespace.c:3664 do_mount fs/namespace.c:3677 [inline] __do_sys_mount fs/namespace.c:3886 [inline] __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3863 __x64_sys_mount+0x67/0x80 fs/namespace.c:3863 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b read to 0xffffffff86ef7d90 of 8 bytes by task 25231 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:2627 [inline] process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2700 worker_thread+0x525/0x730 kernel/workqueue.c:2781 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: 0x0000000100020cec -> 0x0000000100020e18 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 25231 Comm: kworker/u4:25 Not tainted 6.7.0-rc8-syzkaller-00024-gac865f00af29 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Workqueue: ext4-rsv-conversion ext4_end_io_rsv_work ==================================================================