syzbot

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BUG: KCSAN: data-race in do_sync_mmap_readahead / do_sync_mmap_readahead

write to 0xffff888103215da4 of 4 bytes by task 10566 on cpu 1:
 do_sync_mmap_readahead+0x34e/0x3b0 mm/filemap.c:3185
 filemap_fault+0x3d7/0xb60 mm/filemap.c:3279
 __do_fault mm/memory.c:4176 [inline]
 do_cow_fault mm/memory.c:4560 [inline]
 do_fault mm/memory.c:4661 [inline]
 do_pte_missing mm/memory.c:3647 [inline]
 handle_pte_fault mm/memory.c:4947 [inline]
 __handle_mm_fault mm/memory.c:5089 [inline]
 handle_mm_fault+0x1b38/0x2c60 mm/memory.c:5243
 do_user_addr_fault arch/x86/mm/fault.c:1440 [inline]
 handle_page_fault arch/x86/mm/fault.c:1534 [inline]
 exc_page_fault+0x68e/0x790 arch/x86/mm/fault.c:1590
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570

write to 0xffff888103215da4 of 4 bytes by task 10567 on cpu 0:
 do_sync_mmap_readahead+0x34e/0x3b0 mm/filemap.c:3185
 filemap_fault+0x3d7/0xb60 mm/filemap.c:3279
 __do_fault mm/memory.c:4176 [inline]
 do_read_fault mm/memory.c:4530 [inline]
 do_fault mm/memory.c:4659 [inline]
 do_pte_missing mm/memory.c:3647 [inline]
 handle_pte_fault mm/memory.c:4947 [inline]
 __handle_mm_fault mm/memory.c:5089 [inline]
 handle_mm_fault+0x12f4/0x2c60 mm/memory.c:5243
 do_user_addr_fault arch/x86/mm/fault.c:1440 [inline]
 handle_page_fault arch/x86/mm/fault.c:1534 [inline]
 exc_page_fault+0x68e/0x790 arch/x86/mm/fault.c:1590
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
 iovec_from_user+0xe0/0x1f0 lib/iov_iter.c:1842
 __import_iovec+0xe5/0x540 lib/iov_iter.c:1887
 import_iovec+0xbb/0xd0 lib/iov_iter.c:1952
 vfs_readv fs/read_write.c:913 [inline]
 do_readv+0x146/0x2b0 fs/read_write.c:952
 __do_sys_readv fs/read_write.c:1043 [inline]
 __se_sys_readv fs/read_write.c:1040 [inline]
 __x64_sys_readv+0x45/0x50 fs/read_write.c:1040
 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: 0x00000000 -> 0x00000008

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 10567 Comm: syz-executor.0 Not tainted 6.3.0-syzkaller-12378-gc8c655c34e33 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
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