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BUG: KCSAN: data-race in next_uptodate_folio / shmem_write_end

write to 0xffff888108f428c0 of 8 bytes by task 12652 on cpu 1:
 i_size_write include/linux/fs.h:932 [inline]
 shmem_write_end+0x9a/0x470 mm/shmem.c:2713
 generic_perform_write+0x267/0x410 mm/filemap.c:3953
 shmem_file_write_iter+0xc8/0xe0 mm/shmem.c:2865
 call_write_iter include/linux/fs.h:1985 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x4ab/0x7d0 fs/read_write.c:584
 ksys_write+0xeb/0x1a0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:646
 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 0xffff888108f428c0 of 8 bytes by task 12661 on cpu 0:
 i_size_read include/linux/fs.h:910 [inline]
 next_uptodate_folio+0x5bb/0x6e0 mm/filemap.c:3459
 filemap_map_pages+0x5b7/0x6b0 mm/filemap.c:3586
 do_fault_around mm/memory.c:4525 [inline]
 do_read_fault mm/memory.c:4558 [inline]
 do_fault mm/memory.c:4705 [inline]
 do_pte_missing mm/memory.c:3669 [inline]
 handle_pte_fault mm/memory.c:4978 [inline]
 __handle_mm_fault mm/memory.c:5119 [inline]
 handle_mm_fault+0x1116/0x2cc0 mm/memory.c:5284
 faultin_page mm/gup.c:956 [inline]
 __get_user_pages+0x402/0xe40 mm/gup.c:1239
 populate_vma_page_range mm/gup.c:1666 [inline]
 __mm_populate+0x216/0x330 mm/gup.c:1775
 mm_populate include/linux/mm.h:3305 [inline]
 vm_mmap_pgoff+0x1a7/0x240 mm/util.c:551
 ksys_mmap_pgoff+0x2b8/0x330 mm/mmap.c:1400
 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: 0x0000000000cd6000 -> 0x0000000000cdc000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 12661 Comm: syz-executor.4 Not tainted 6.5.0-syzkaller-11812-g7733171926cc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
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