================================================================== BUG: KCSAN: data-race in ext4_write_end / mpage_process_page_bufs write to 0xffff8881324cebc8 of 8 bytes by task 15318 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] new_sync_write fs/read_write.c:507 [inline] vfs_write+0x7bc/0x900 fs/read_write.c:594 ksys_write+0xd9/0x190 fs/read_write.c:647 __do_sys_write fs/read_write.c:659 [inline] __se_sys_write fs/read_write.c:656 [inline] __x64_sys_write+0x3e/0x50 fs/read_write.c:656 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 0xffff8881324cebc8 of 8 bytes by task 15322 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 filemap_fdatawrite_wbc mm/filemap.c:400 [inline] __filemap_fdatawrite_range mm/filemap.c:433 [inline] __filemap_fdatawrite mm/filemap.c:439 [inline] filemap_flush+0x154/0x180 mm/filemap.c:466 ext4_alloc_da_blocks+0x47/0xd0 fs/ext4/inode.c:3170 __ext4_ioctl fs/ext4/ioctl.c:1041 [inline] ext4_ioctl+0xc03/0x2190 fs/ext4/ioctl.c:1279 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:860 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:860 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 value changed: 0x00000000006b3000 -> 0x00000000006b4000 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 15322 Comm: syz-executor.2 Not tainted 5.15.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================