================================================================== BUG: KCSAN: data-race in generic_write_end / next_uptodate_page write to 0xffff8881061db600 of 8 bytes by task 5661 on cpu 1: i_size_write include/linux/fs.h:871 [inline] generic_write_end+0x96/0x180 fs/buffer.c:2207 ext4_da_write_end+0x59b/0x730 fs/ext4/inode.c:3110 generic_perform_write+0x23e/0x3a0 mm/filemap.c:3671 ext4_buffered_write_iter+0x2f2/0x3f0 fs/ext4/file.c:269 ext4_file_write_iter+0x2e7/0x11d0 fs/ext4/file.c:519 call_write_iter include/linux/fs.h:2114 [inline] new_sync_write fs/read_write.c:518 [inline] vfs_write+0x69d/0x770 fs/read_write.c:605 ksys_write+0xce/0x180 fs/read_write.c:658 __do_sys_write fs/read_write.c:670 [inline] __se_sys_write fs/read_write.c:667 [inline] __x64_sys_write+0x3e/0x50 fs/read_write.c:667 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff8881061db600 of 8 bytes by task 5666 on cpu 0: i_size_read include/linux/fs.h:849 [inline] next_uptodate_page+0x323/0x670 mm/filemap.c:3146 next_map_page mm/filemap.c:3171 [inline] filemap_map_pages+0x761/0x870 mm/filemap.c:3227 do_fault_around mm/memory.c:3961 [inline] do_read_fault mm/memory.c:3975 [inline] do_fault mm/memory.c:4108 [inline] handle_pte_fault mm/memory.c:4367 [inline] __handle_mm_fault mm/memory.c:4502 [inline] handle_mm_fault+0xda3/0x1a70 mm/memory.c:4600 faultin_page mm/gup.c:908 [inline] __get_user_pages+0x947/0xee0 mm/gup.c:1127 populate_vma_page_range mm/gup.c:1460 [inline] __mm_populate+0x24d/0x380 mm/gup.c:1508 mm_populate include/linux/mm.h:2621 [inline] vm_mmap_pgoff+0x145/0x1d0 mm/util.c:524 ksys_mmap_pgoff+0x2a8/0x380 mm/mmap.c:1638 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: 0 PID: 5666 Comm: syz-executor.0 Not tainted 5.12.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================