================================================================== BUG: KCSAN: data-race in generic_file_read_iter / simple_write_end write to 0xffff888128be4898 of 8 bytes by task 21186 on cpu 1: i_size_write include/linux/fs.h:888 [inline] simple_write_end+0x1d0/0x370 fs/libfs.c:517 generic_perform_write+0x1d3/0x320 mm/filemap.c:3316 __generic_file_write_iter+0x251/0x380 mm/filemap.c:3434 generic_file_write_iter+0x28c/0x390 mm/filemap.c:3466 call_write_iter include/linux/fs.h:1895 [inline] do_iter_readv_writev+0x487/0x5b0 fs/read_write.c:693 do_iter_write fs/read_write.c:970 [inline] do_iter_write+0x13b/0x3c0 fs/read_write.c:951 vfs_iter_write+0x5c/0x80 fs/read_write.c:983 iter_file_splice_write+0x4c0/0x7f0 fs/splice.c:746 do_splice_from fs/splice.c:848 [inline] direct_splice_actor+0xa0/0xc0 fs/splice.c:1020 splice_direct_to_actor+0x215/0x510 fs/splice.c:975 do_splice_direct+0x161/0x1e0 fs/splice.c:1063 do_sendfile+0x384/0x7f0 fs/read_write.c:1464 __do_sys_sendfile64 fs/read_write.c:1519 [inline] __se_sys_sendfile64 fs/read_write.c:1511 [inline] __x64_sys_sendfile64+0xbe/0x140 fs/read_write.c:1511 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff888128be4898 of 8 bytes by task 21191 on cpu 0: generic_file_buffered_read mm/filemap.c:2106 [inline] generic_file_read_iter+0x860/0x1440 mm/filemap.c:2324 call_read_iter include/linux/fs.h:1889 [inline] generic_file_splice_read+0x35c/0x500 fs/splice.c:307 do_splice_to+0xf2/0x130 fs/splice.c:877 splice_direct_to_actor+0x1a1/0x510 fs/splice.c:954 do_splice_direct+0x161/0x1e0 fs/splice.c:1063 do_sendfile+0x384/0x7f0 fs/read_write.c:1464 __do_sys_sendfile64 fs/read_write.c:1519 [inline] __se_sys_sendfile64 fs/read_write.c:1511 [inline] __x64_sys_sendfile64+0xbe/0x140 fs/read_write.c:1511 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 21191 Comm: syz-executor.2 Not tainted 5.4.0-rc7+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================