================================================================== BUG: KCSAN: data-race in ext4_write_end / mpage_process_page_bufs write to 0xffff88812e1386d8 of 8 bytes by task 27995 on cpu 0: i_size_write include/linux/fs.h:916 [inline] ext4_update_inode_size fs/ext4/ext4.h:3421 [inline] ext4_write_end+0x1be/0x800 fs/ext4/inode.c:1311 ext4_da_write_end+0x93/0x730 fs/ext4/inode.c:3085 generic_perform_write+0x251/0x3e0 mm/filemap.c:3781 ext4_buffered_write_iter+0x305/0x400 fs/ext4/file.c:269 ext4_file_write_iter+0x2e7/0x11f0 call_write_iter include/linux/fs.h:2163 [inline] aio_write+0x2b4/0x390 fs/aio.c:1578 io_submit_one+0x86f/0x13b0 fs/aio.c:1880 __do_sys_io_submit fs/aio.c:1939 [inline] __se_sys_io_submit+0x105/0x270 fs/aio.c:1909 __x64_sys_io_submit+0x3f/0x50 fs/aio.c:1909 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff88812e1386d8 of 8 bytes by task 1210 on cpu 1: i_size_read include/linux/fs.h:894 [inline] mpage_process_page_bufs+0x34/0x560 fs/ext4/inode.c:2198 mpage_prepare_extent_to_map+0x4f6/0x650 fs/ext4/inode.c:2632 ext4_writepages+0xa18/0x1d70 fs/ext4/inode.c:2804 do_writepages+0x26b/0x3c0 mm/page-writeback.c:2364 __writeback_single_inode+0x80/0x440 fs/fs-writeback.c:1616 writeback_sb_inodes+0x563/0xd30 fs/fs-writeback.c:1881 wb_writeback+0x27d/0x6d0 fs/fs-writeback.c:2053 wb_do_writeback+0x101/0x530 fs/fs-writeback.c:2196 wb_workfn+0xc8/0x540 fs/fs-writeback.c:2237 process_one_work+0x402/0x910 kernel/workqueue.c:2297 process_scheduled_works kernel/workqueue.c:2360 [inline] worker_thread+0x7ff/0xae0 kernel/workqueue.c:2446 kthread+0x262/0x280 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 value changed: 0x0000000000a07000 -> 0x0000000000a09000 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 1210 Comm: kworker/u4:8 Not tainted 5.15.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: writeback wb_workfn (flush-8:0) ==================================================================