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BUG: KCSAN: data-race in filemap_read / filemap_read

write to 0xffff888104b22e90 of 8 bytes by task 19503 on cpu 1:
 filemap_read+0x44c/0x670 mm/filemap.c:2713
 generic_file_read_iter+0x78/0x340 mm/filemap.c:2837
 ext4_file_read_iter+0x1d8/0x2a0
 call_read_iter include/linux/fs.h:1865 [inline]
 copy_splice_read+0x26b/0x4b0 fs/splice.c:367
 vfs_splice_read fs/splice.c:993 [inline]
 splice_direct_to_actor+0x2aa/0x690 fs/splice.c:1070
 do_splice_direct+0x10d/0x190 fs/splice.c:1195
 do_sendfile+0x3b6/0x9a0 fs/read_write.c:1254
 __do_sys_sendfile64 fs/read_write.c:1322 [inline]
 __se_sys_sendfile64 fs/read_write.c:1308 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888104b22e90 of 8 bytes by task 19491 on cpu 0:
 filemap_read+0x28b/0x670 mm/filemap.c:2685
 generic_file_read_iter+0x78/0x340 mm/filemap.c:2837
 ext4_file_read_iter+0x1d8/0x2a0
 call_read_iter include/linux/fs.h:1865 [inline]
 copy_splice_read+0x26b/0x4b0 fs/splice.c:367
 vfs_splice_read fs/splice.c:993 [inline]
 splice_direct_to_actor+0x2aa/0x690 fs/splice.c:1070
 do_splice_direct+0x10d/0x190 fs/splice.c:1195
 do_sendfile+0x3b6/0x9a0 fs/read_write.c:1254
 __do_sys_sendfile64 fs/read_write.c:1322 [inline]
 __se_sys_sendfile64 fs/read_write.c:1308 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000001e3d000 -> 0x0000000001e3e000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 19491 Comm: syz-executor.3 Not tainted 6.5.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023
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