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BUG: KCSAN: data-race in next_uptodate_page / shmem_write_end

write to 0xffff888126c0e118 of 8 bytes by task 3725 on cpu 1:
 i_size_write include/linux/fs.h:871 [inline]
 shmem_write_end+0x59/0x380 mm/shmem.c:2496
 generic_perform_write+0x264/0x3f0 mm/filemap.c:3790
 __generic_file_write_iter+0xe3/0x280 mm/filemap.c:3907
 generic_file_write_iter+0x75/0x130 mm/filemap.c:3939
 call_write_iter include/linux/fs.h:2058 [inline]
 new_sync_write fs/read_write.c:504 [inline]
 vfs_write+0x71c/0x890 fs/read_write.c:591
 ksys_write+0xe8/0x1a0 fs/read_write.c:644
 __do_sys_write fs/read_write.c:656 [inline]
 __se_sys_write fs/read_write.c:653 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:653
 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 0xffff888126c0e118 of 8 bytes by task 3726 on cpu 0:
 i_size_read include/linux/fs.h:849 [inline]
 next_uptodate_page+0x26f/0x4e0 mm/filemap.c:3321
 next_map_page mm/filemap.c:3346 [inline]
 filemap_map_pages+0x9d1/0xae0 mm/filemap.c:3418
 do_fault_around mm/memory.c:4483 [inline]
 do_read_fault mm/memory.c:4509 [inline]
 do_fault+0x433/0xb20 mm/memory.c:4643
 handle_pte_fault mm/memory.c:4907 [inline]
 __handle_mm_fault mm/memory.c:5046 [inline]
 handle_mm_fault+0x889/0xa90 mm/memory.c:5144
 faultin_page mm/gup.c:955 [inline]
 __get_user_pages+0x34a/0xbf0 mm/gup.c:1176
 populate_vma_page_range mm/gup.c:1520 [inline]
 __mm_populate+0x26e/0x3a0 mm/gup.c:1633
 mm_populate include/linux/mm.h:2710 [inline]
 vm_mmap_pgoff+0x160/0x1f0 mm/util.c:557
 ksys_mmap_pgoff+0x265/0x320 mm/mmap.c:1633
 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: 0x0000000000ea8000 -> 0x0000000000eab000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3726 Comm: syz-executor.2 Not tainted 5.19.0-syzkaller-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
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