================================================================== BUG: KCSAN: data-race in __filemap_add_folio / ext4_writepages write to 0xffff88813acaac60 of 8 bytes by task 29854 on cpu 0: __filemap_add_folio+0x256/0x4d0 mm/filemap.c:946 filemap_add_folio+0x6b/0x150 mm/filemap.c:999 __filemap_get_folio+0x4c4/0x690 mm/filemap.c:1962 pagecache_get_page+0x26/0xe0 mm/folio-compat.c:125 grab_cache_page_write_begin+0x3f/0x50 mm/folio-compat.c:139 ext4_da_write_begin+0x323/0x590 fs/ext4/inode.c:2958 generic_perform_write+0x1c8/0x400 mm/filemap.c:3756 ext4_buffered_write_iter+0x25b/0x380 fs/ext4/file.c:269 ext4_file_write_iter+0x2e7/0x1200 call_write_iter include/linux/fs.h:2162 [inline] do_iter_readv_writev+0x2de/0x380 fs/read_write.c:725 do_iter_write+0x192/0x5c0 fs/read_write.c:851 vfs_iter_write+0x4c/0x70 fs/read_write.c:892 iter_file_splice_write+0x43a/0x790 fs/splice.c:689 do_splice_from fs/splice.c:767 [inline] direct_splice_actor+0x80/0xa0 fs/splice.c:936 splice_direct_to_actor+0x345/0x650 fs/splice.c:891 do_splice_direct+0x106/0x190 fs/splice.c:979 do_sendfile+0x675/0xc40 fs/read_write.c:1245 __do_sys_sendfile64 fs/read_write.c:1310 [inline] __se_sys_sendfile64 fs/read_write.c:1296 [inline] __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1296 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffff88813acaac60 of 8 bytes by task 29855 on cpu 1: ext4_writepages+0x16d/0x1e80 fs/ext4/inode.c:2663 do_writepages+0x1cb/0x330 mm/page-writeback.c:2364 filemap_fdatawrite_wbc mm/filemap.c:407 [inline] __filemap_fdatawrite_range mm/filemap.c:440 [inline] file_write_and_wait_range+0x132/0x1d0 mm/filemap.c:824 ext4_sync_file+0x105/0x6e0 fs/ext4/fsync.c:151 vfs_fsync_range+0x107/0x120 fs/sync.c:182 generic_write_sync include/linux/fs.h:2955 [inline] ext4_buffered_write_iter+0x322/0x380 fs/ext4/file.c:277 ext4_file_write_iter+0x2e7/0x1200 call_write_iter include/linux/fs.h:2162 [inline] do_iter_readv_writev+0x2de/0x380 fs/read_write.c:725 do_iter_write+0x192/0x5c0 fs/read_write.c:851 vfs_iter_write+0x4c/0x70 fs/read_write.c:892 iter_file_splice_write+0x43a/0x790 fs/splice.c:689 do_splice_from fs/splice.c:767 [inline] direct_splice_actor+0x80/0xa0 fs/splice.c:936 splice_direct_to_actor+0x345/0x650 fs/splice.c:891 do_splice_direct+0x106/0x190 fs/splice.c:979 do_sendfile+0x675/0xc40 fs/read_write.c:1245 __do_sys_sendfile64 fs/read_write.c:1310 [inline] __se_sys_sendfile64 fs/read_write.c:1296 [inline] __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1296 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x0000000000003321 -> 0x0000000000003322 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 29855 Comm: syz-executor.2 Not tainted 5.16.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================