================================================================== BUG: KCSAN: data-race in wq_worker_tick / wq_worker_tick read-write to 0xffff8881010754b8 of 8 bytes by interrupt on cpu 0: wq_worker_tick+0x63/0x240 kernel/workqueue.c:1474 sched_tick+0xd2/0x110 kernel/sched/core.c:5616 update_process_times+0x15a/0x180 kernel/time/timer.c:2524 tick_sched_handle kernel/time/tick-sched.c:276 [inline] tick_nohz_handler+0x250/0x2d0 kernel/time/tick-sched.c:297 __run_hrtimer kernel/time/hrtimer.c:1691 [inline] __hrtimer_run_queues+0x20d/0x5e0 kernel/time/hrtimer.c:1755 hrtimer_interrupt+0x210/0x7b0 kernel/time/hrtimer.c:1817 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1026 [inline] __sysvec_apic_timer_interrupt+0x5c/0x1a0 arch/x86/kernel/apic/apic.c:1043 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline] sysvec_apic_timer_interrupt+0x6e/0x80 arch/x86/kernel/apic/apic.c:1037 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 __sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:213 __filemap_get_folio+0x30/0x5b0 mm/filemap.c:1883 grow_dev_folio fs/buffer.c:1043 [inline] grow_buffers fs/buffer.c:1109 [inline] __getblk_slow fs/buffer.c:1135 [inline] bdev_getblk+0x173/0x3b0 fs/buffer.c:1437 sb_getblk_gfp include/linux/buffer_head.h:392 [inline] __read_extent_tree_block+0xb0/0x480 fs/ext4/extents.c:565 ext4_find_extent+0x501/0x7c0 fs/ext4/extents.c:938 ext4_ext_map_blocks+0x11f/0x35c0 fs/ext4/extents.c:4205 ext4_map_create_blocks fs/ext4/inode.c:516 [inline] ext4_map_blocks+0x592/0xcf0 fs/ext4/inode.c:702 mpage_map_one_extent fs/ext4/inode.c:2208 [inline] mpage_map_and_submit_extent fs/ext4/inode.c:2261 [inline] ext4_do_writepages+0x14c3/0x2130 fs/ext4/inode.c:2724 ext4_writepages+0x159/0x2e0 fs/ext4/inode.c:2813 do_writepages+0x1d8/0x480 mm/page-writeback.c:2683 __writeback_single_inode+0x89/0x850 fs/fs-writeback.c:1658 writeback_sb_inodes+0x461/0xa30 fs/fs-writeback.c:1954 wb_writeback+0x262/0x640 fs/fs-writeback.c:2134 wb_do_writeback fs/fs-writeback.c:2281 [inline] wb_workfn+0x1a8/0x940 fs/fs-writeback.c:2321 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3310 worker_thread+0x51d/0x6f0 kernel/workqueue.c:3391 kthread+0x1d1/0x210 kernel/kthread.c:389 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 read-write to 0xffff8881010754b8 of 8 bytes by interrupt on cpu 1: wq_worker_tick+0x63/0x240 kernel/workqueue.c:1474 sched_tick+0xd2/0x110 kernel/sched/core.c:5616 update_process_times+0x15a/0x180 kernel/time/timer.c:2524 tick_sched_handle kernel/time/tick-sched.c:276 [inline] tick_nohz_handler+0x250/0x2d0 kernel/time/tick-sched.c:297 __run_hrtimer kernel/time/hrtimer.c:1691 [inline] __hrtimer_run_queues+0x20d/0x5e0 kernel/time/hrtimer.c:1755 hrtimer_interrupt+0x210/0x7b0 kernel/time/hrtimer.c:1817 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1026 [inline] __sysvec_apic_timer_interrupt+0x5c/0x1a0 arch/x86/kernel/apic/apic.c:1043 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline] sysvec_apic_timer_interrupt+0x6e/0x80 arch/x86/kernel/apic/apic.c:1037 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 is_atomic kernel/kcsan/core.c:249 [inline] should_watch kernel/kcsan/core.c:277 [inline] check_access kernel/kcsan/core.c:752 [inline] __tsan_read4+0xe5/0x180 kernel/kcsan/core.c:1024 ext4_has_feature_quota fs/ext4/ext4.h:2134 [inline] ext4_quota_capable fs/ext4/ext4.h:3522 [inline] ext4_meta_trans_blocks fs/ext4/inode.c:5690 [inline] ext4_da_writepages_trans_blocks fs/ext4/inode.c:2344 [inline] ext4_do_writepages+0x934/0x2130 fs/ext4/inode.c:2704 ext4_writepages+0x159/0x2e0 fs/ext4/inode.c:2813 do_writepages+0x1d8/0x480 mm/page-writeback.c:2683 __writeback_single_inode+0x89/0x850 fs/fs-writeback.c:1658 writeback_sb_inodes+0x461/0xa30 fs/fs-writeback.c:1954 wb_writeback+0x262/0x640 fs/fs-writeback.c:2134 wb_do_writeback fs/fs-writeback.c:2281 [inline] wb_workfn+0x1a8/0x940 fs/fs-writeback.c:2321 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3310 worker_thread+0x51d/0x6f0 kernel/workqueue.c:3391 kthread+0x1d1/0x210 kernel/kthread.c:389 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 value changed: 0x0000000008959220 -> 0x000000000895b930 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 6930 Comm: kworker/u8:9 Not tainted 6.12.0-rc2-syzkaller-00305-g7234e2ea0edd #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: writeback wb_workfn (flush-7:4) ==================================================================