==================================================================
BUG: KCSAN: data-race in ondemand_readahead / ondemand_readahead

read to 0xffff888103fce178 of 8 bytes by task 7799 on cpu 0:
 ondemand_readahead+0x133/0x6b0 mm/readahead.c:581
 page_cache_async_ra+0x94/0xa0 mm/readahead.c:718
 do_async_mmap_readahead mm/filemap.c:3203 [inline]
 filemap_fault+0x2d3/0xa60 mm/filemap.c:3299
 __do_fault+0xb6/0x200 mm/memory.c:4556
 do_read_fault mm/memory.c:4920 [inline]
 do_fault mm/memory.c:5050 [inline]
 do_pte_missing mm/memory.c:3897 [inline]
 handle_pte_fault mm/memory.c:5380 [inline]
 __handle_mm_fault mm/memory.c:5523 [inline]
 handle_mm_fault+0xdeb/0x2a80 mm/memory.c:5688
 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline]
 handle_page_fault arch/x86/mm/fault.c:1481 [inline]
 exc_page_fault+0x296/0x650 arch/x86/mm/fault.c:1539
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
 rep_movs_alternative+0x4a/0x70 arch/x86/lib/copy_user_64.S:65
 copy_user_generic arch/x86/include/asm/uaccess_64.h:110 [inline]
 raw_copy_from_user arch/x86/include/asm/uaccess_64.h:125 [inline]
 copy_from_user_iter lib/iov_iter.c:55 [inline]
 iterate_ubuf include/linux/iov_iter.h:29 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:245 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 __copy_from_iter lib/iov_iter.c:249 [inline]
 _copy_from_iter+0x13a/0xb00 lib/iov_iter.c:260
 copy_from_iter include/linux/uio.h:204 [inline]
 copy_from_iter_full include/linux/uio.h:221 [inline]
 skb_do_copy_data_nocache include/net/sock.h:2162 [inline]
 skb_copy_to_page_nocache include/net/sock.h:2188 [inline]
 tcp_sendmsg_locked+0x13d1/0x2640 net/ipv4/tcp.c:1215
 tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1351
 inet_sendmsg+0x77/0xd0 net/ipv4/af_inet.c:853
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x102/0x180 net/socket.c:745
 __sys_sendto+0x1e5/0x260 net/socket.c:2192
 __do_sys_sendto net/socket.c:2204 [inline]
 __se_sys_sendto net/socket.c:2200 [inline]
 __x64_sys_sendto+0x78/0x90 net/socket.c:2200
 x64_sys_call+0x16d7/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

write to 0xffff888103fce178 of 8 bytes by task 7807 on cpu 1:
 ondemand_readahead+0x588/0x6b0 mm/readahead.c:607
 page_cache_async_ra+0x94/0xa0 mm/readahead.c:718
 do_async_mmap_readahead mm/filemap.c:3203 [inline]
 filemap_fault+0x2d3/0xa60 mm/filemap.c:3299
 __do_fault+0xb6/0x200 mm/memory.c:4556
 do_read_fault mm/memory.c:4920 [inline]
 do_fault mm/memory.c:5050 [inline]
 do_pte_missing mm/memory.c:3897 [inline]
 handle_pte_fault mm/memory.c:5380 [inline]
 __handle_mm_fault mm/memory.c:5523 [inline]
 handle_mm_fault+0xdeb/0x2a80 mm/memory.c:5688
 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline]
 handle_page_fault arch/x86/mm/fault.c:1481 [inline]
 exc_page_fault+0x296/0x650 arch/x86/mm/fault.c:1539