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

write to 0xffff88813e9bfca4 of 4 bytes by task 14206 on cpu 1:
 try_context_readahead mm/readahead.c:460 [inline]
 ondemand_readahead+0x69b/0x6d0 mm/readahead.c:647
 page_cache_sync_ra+0xdc/0xf0 mm/readahead.c:709
 page_cache_sync_readahead include/linux/pagemap.h:1213 [inline]
 filemap_get_pages mm/filemap.c:2581 [inline]
 filemap_read+0x3fd/0x1510 mm/filemap.c:2675
 generic_file_read_iter+0x72/0x320 mm/filemap.c:2821
 call_read_iter include/linux/fs.h:2193 [inline]
 generic_file_splice_read+0xde/0x2b0 fs/splice.c:309
 do_splice_to fs/splice.c:793 [inline]
 splice_direct_to_actor+0x26c/0x620 fs/splice.c:865
 do_splice_direct+0xfb/0x180 fs/splice.c:974
 do_sendfile+0x3bf/0x910 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64 fs/read_write.c:1309 [inline]
 __x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1309
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88813e9bfca4 of 4 bytes by task 14208 on cpu 0:
 page_cache_ra_order mm/readahead.c:560 [inline]
 ondemand_readahead+0x4d4/0x6d0 mm/readahead.c:682
 page_cache_sync_ra+0xdc/0xf0 mm/readahead.c:709
 page_cache_sync_readahead include/linux/pagemap.h:1213 [inline]
 filemap_get_pages mm/filemap.c:2581 [inline]
 filemap_read+0x3fd/0x1510 mm/filemap.c:2675
 generic_file_read_iter+0x72/0x320 mm/filemap.c:2821
 call_read_iter include/linux/fs.h:2193 [inline]
 generic_file_splice_read+0xde/0x2b0 fs/splice.c:309
 do_splice_to fs/splice.c:793 [inline]
 splice_direct_to_actor+0x26c/0x620 fs/splice.c:865
 do_splice_direct+0xfb/0x180 fs/splice.c:974
 do_sendfile+0x3bf/0x910 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64 fs/read_write.c:1309 [inline]
 __x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1309
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00000020 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 14208 Comm: syz-executor.4 Not tainted 6.1.0-rc7-syzkaller-00190-g97ee9d1c1696-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
==================================================================