================================================================== BUG: KCSAN: data-race in __xa_clear_mark / xas_find_marked write to 0xffff88810676b470 of 8 bytes by task 1776 on cpu 0: instrument_write include/linux/instrumented.h:42 [inline] __instrument_read_write_bitop include/asm-generic/bitops/instrumented-non-atomic.h:79 [inline] __test_and_clear_bit include/asm-generic/bitops/instrumented-non-atomic.h:109 [inline] node_clear_mark lib/xarray.c:100 [inline] xas_clear_mark lib/xarray.c:911 [inline] __xa_clear_mark+0x1d9/0x2c0 lib/xarray.c:1917 test_clear_page_writeback+0x23e/0x560 mm/page-writeback.c:2736 end_page_writeback+0xd7/0x1b0 mm/filemap.c:1548 ext4_finish_bio+0x3e2/0x430 fs/ext4/page-io.c:143 ext4_release_io_end+0x98/0x200 fs/ext4/page-io.c:158 ext4_end_io_end fs/ext4/page-io.c:192 [inline] ext4_do_flush_completed_IO fs/ext4/page-io.c:257 [inline] ext4_end_io_rsv_work+0x306/0x360 fs/ext4/page-io.c:271 process_one_work+0x3e9/0x8f0 kernel/workqueue.c:2276 worker_thread+0x636/0xae0 kernel/workqueue.c:2422 kthread+0x1d0/0x1f0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 read to 0xffff88810676b470 of 8 bytes by task 4878 on cpu 1: xas_find_chunk include/linux/xarray.h:1662 [inline] xas_find_marked+0x195/0x5f0 lib/xarray.c:1349 find_get_entry mm/filemap.c:1925 [inline] find_get_pages_range_tag+0xf2/0x390 mm/filemap.c:2216 pagevec_lookup_range_tag+0x37/0x50 mm/swap.c:1123 __filemap_fdatawait_range+0xab/0x1b0 mm/filemap.c:510 filemap_fdatawait_keep_errors+0x24/0x80 mm/filemap.c:613 wait_sb_inodes fs/fs-writeback.c:2458 [inline] sync_inodes_sb+0x3f6/0x4d0 fs/fs-writeback.c:2580 sync_inodes_one_sb+0x39/0x50 fs/sync.c:74 iterate_supers+0x137/0x1f0 fs/super.c:695 ksys_sync+0x59/0xe0 fs/sync.c:114 __do_sys_sync+0xa/0x10 fs/sync.c:125 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 4878 Comm: syz-executor.1 Not tainted 5.13.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================