================================================================== BUG: KCSAN: data-race in fprop_new_period / fprop_reflect_period_percpu read-write to 0xffffffff870ca3f0 of 4 bytes by interrupt on cpu 1: fprop_new_period+0xa6/0xd0 lib/flex_proportions.c:78 writeout_period+0x55/0xe0 mm/page-writeback.c:612 call_timer_fn+0x2e/0x240 kernel/time/timer.c:1474 expire_timers+0x116/0x240 kernel/time/timer.c:1519 __run_timers+0x350/0x400 kernel/time/timer.c:1790 run_timer_softirq+0x56/0x60 kernel/time/timer.c:1805 __do_softirq+0x158/0x2e3 kernel/softirq.c:571 __irq_exit_rcu kernel/softirq.c:650 [inline] irq_exit_rcu+0x41/0x70 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x8d/0xb0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 check_access kernel/kcsan/core.c:739 [inline] __tsan_read8+0x10d/0x180 kernel/kcsan/core.c:1014 rb_red_parent lib/rbtree.c:66 [inline] __rb_insert lib/rbtree.c:88 [inline] __rb_insert_augmented+0x1e/0x2f0 lib/rbtree.c:459 rb_insert_augmented include/linux/rbtree_augmented.h:50 [inline] rb_insert_augmented_cached include/linux/rbtree_augmented.h:60 [inline] vma_interval_tree_insert+0x1d1/0x1e0 mm/interval_tree.c:23 __vma_adjust+0x5dc/0x2000 mm/mmap.c:854 vma_merge+0x7a1/0x7c0 mmap_region+0x6c4/0xff0 mm/mmap.c:1722 do_mmap+0x67a/0xb20 mm/mmap.c:1540 vm_mmap_pgoff+0x117/0x1f0 mm/util.c:552 ksys_mmap_pgoff+0x265/0x320 mm/mmap.c:1586 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd read to 0xffffffff870ca3f0 of 4 bytes by interrupt on cpu 0: fprop_reflect_period_percpu+0x22/0x1a0 lib/flex_proportions.c:186 __fprop_add_percpu lib/flex_proportions.c:217 [inline] __fprop_add_percpu_max+0x54/0x180 lib/flex_proportions.c:275 wb_domain_writeout_add mm/page-writeback.c:559 [inline] __wb_writeout_add+0x7e/0x1d0 mm/page-writeback.c:583 __folio_end_writeback+0x2f4/0x580 mm/page-writeback.c:2931 folio_end_writeback+0x57/0x130 mm/filemap.c:1620 end_page_writeback+0x3b/0xe0 mm/folio-compat.c:26 end_buffer_async_write+0x21b/0x310 fs/buffer.c:375 end_bio_bh_io_sync+0x6f/0x90 fs/buffer.c:2672 bio_endio+0x366/0x3f0 block/bio.c:1564 req_bio_endio block/blk-mq.c:695 [inline] blk_update_request+0x311/0x850 block/blk-mq.c:825 blk_mq_end_request+0x22/0x50 block/blk-mq.c:951 lo_complete_rq+0xca/0x170 drivers/block/loop.c:370 blk_complete_reqs block/blk-mq.c:1022 [inline] blk_done_softirq+0x92/0xc0 block/blk-mq.c:1027 __do_softirq+0x158/0x2e3 kernel/softirq.c:571 run_ksoftirqd+0x1f/0x30 kernel/softirq.c:934 smpboot_thread_fn+0x308/0x4a0 kernel/smpboot.c:164 kthread+0x1a9/0x1e0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 value changed: 0x00000057 -> 0x00000058 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 13 Comm: ksoftirqd/0 Not tainted 6.0.0-rc5-syzkaller-00094-ga335366bad13-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 ==================================================================