================================================================== BUG: KCSAN: data-race in write_cache_pages / write_cache_pages write to 0xffff88812a3ccd38 of 8 bytes by task 8019 on cpu 1: write_cache_pages+0x7be/0xb40 mm/page-writeback.c:2289 generic_writepages mm/page-writeback.c:2329 [inline] generic_writepages+0x79/0xc0 mm/page-writeback.c:2318 blkdev_writepages+0x27/0x40 fs/block_dev.c:2060 do_writepages+0x6b/0x170 mm/page-writeback.c:2344 __filemap_fdatawrite_range+0x1c5/0x230 mm/filemap.c:421 __filemap_fdatawrite mm/filemap.c:429 [inline] filemap_fdatawrite mm/filemap.c:434 [inline] filemap_write_and_wait mm/filemap.c:640 [inline] filemap_write_and_wait+0xad/0x150 mm/filemap.c:635 __sync_blockdev+0x5d/0x90 fs/block_dev.c:491 __sync_filesystem fs/sync.c:40 [inline] sync_filesystem fs/sync.c:67 [inline] sync_filesystem+0x186/0x1a0 fs/sync.c:48 ovl_sync_fs+0x92/0xa0 fs/overlayfs/super.c:276 __sync_filesystem fs/sync.c:39 [inline] sync_filesystem fs/sync.c:67 [inline] sync_filesystem+0x168/0x1a0 fs/sync.c:48 generic_shutdown_super+0x6b/0x260 fs/super.c:448 kill_anon_super+0x2f/0x50 fs/super.c:1106 deactivate_locked_super+0x64/0xb0 fs/super.c:335 deactivate_super fs/super.c:366 [inline] deactivate_super+0xca/0xe0 fs/super.c:362 cleanup_mnt+0x27f/0x330 fs/namespace.c:1102 __cleanup_mnt+0x1f/0x30 fs/namespace.c:1109 task_work_run+0xf6/0x130 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x2b4/0x2c0 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath arch/x86/entry/common.c:278 [inline] do_syscall_64+0x384/0x3a0 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x44/0xa9 write to 0xffff88812a3ccd38 of 8 bytes by task 8014 on cpu 0: write_cache_pages+0x7be/0xb40 mm/page-writeback.c:2289 generic_writepages mm/page-writeback.c:2329 [inline] generic_writepages+0x79/0xc0 mm/page-writeback.c:2318 blkdev_writepages+0x27/0x40 fs/block_dev.c:2060 do_writepages+0x6b/0x170 mm/page-writeback.c:2344 __filemap_fdatawrite_range+0x1c5/0x230 mm/filemap.c:421 __filemap_fdatawrite mm/filemap.c:429 [inline] filemap_fdatawrite mm/filemap.c:434 [inline] filemap_write_and_wait mm/filemap.c:640 [inline] filemap_write_and_wait+0xad/0x150 mm/filemap.c:635 __sync_blockdev+0x5d/0x90 fs/block_dev.c:491 __sync_filesystem fs/sync.c:40 [inline] sync_filesystem fs/sync.c:67 [inline] sync_filesystem+0x186/0x1a0 fs/sync.c:48 ovl_sync_fs+0x92/0xa0 fs/overlayfs/super.c:276 __sync_filesystem fs/sync.c:39 [inline] sync_filesystem fs/sync.c:67 [inline] sync_filesystem+0x168/0x1a0 fs/sync.c:48 generic_shutdown_super+0x6b/0x260 fs/super.c:448 kill_anon_super+0x2f/0x50 fs/super.c:1106 deactivate_locked_super+0x64/0xb0 fs/super.c:335 deactivate_super fs/super.c:366 [inline] deactivate_super+0xca/0xe0 fs/super.c:362 cleanup_mnt+0x27f/0x330 fs/namespace.c:1102 __cleanup_mnt+0x1f/0x30 fs/namespace.c:1109 task_work_run+0xf6/0x130 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x2b4/0x2c0 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath arch/x86/entry/common.c:278 [inline] do_syscall_64+0x384/0x3a0 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 8014 Comm: syz-executor.0 Not tainted 5.5.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================