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BUG: KCSAN: data-race in generic_write_end / next_uptodate_page

write to 0xffff88810b1b8c58 of 8 bytes by task 31085 on cpu 0:
 i_size_write include/linux/fs.h:886 [inline]
 generic_write_end+0xb4/0x360 fs/buffer.c:2168
 ext4_da_write_end+0x4bd/0x630 fs/ext4/inode.c:3175
 generic_perform_write+0x253/0x3d0 mm/filemap.c:3783
 ext4_buffered_write_iter+0x234/0x3e0 fs/ext4/file.c:285
 ext4_file_write_iter+0x2d2/0x1270
 call_write_iter include/linux/fs.h:2189 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x45a/0x750 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 0xffff88810b1b8c58 of 8 bytes by task 31086 on cpu 1:
 i_size_read include/linux/fs.h:864 [inline]
 next_uptodate_page+0x47b/0x560 mm/filemap.c:3327
 next_map_page mm/filemap.c:3352 [inline]
 filemap_map_pages+0x722/0x830 mm/filemap.c:3424
 do_fault_around mm/memory.c:4486 [inline]
 do_read_fault mm/memory.c:4512 [inline]
 do_fault mm/memory.c:4646 [inline]
 handle_pte_fault mm/memory.c:4934 [inline]
 __handle_mm_fault mm/memory.c:5076 [inline]
 handle_mm_fault+0x1044/0x24d0 mm/memory.c:5222
 faultin_page mm/gup.c:926 [inline]
 __get_user_pages+0x353/0xc60 mm/gup.c:1153
 populate_vma_page_range mm/gup.c:1526 [inline]
 __mm_populate+0x23a/0x360 mm/gup.c:1640
 mm_populate include/linux/mm.h:2880 [inline]
 vm_mmap_pgoff+0x174/0x210 mm/util.c:525
 ksys_mmap_pgoff+0x2ac/0x320 mm/mmap.c:1457
 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: 0x0000000000b72000 -> 0x0000000000b74000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 31086 Comm: syz-executor.4 Not tainted 6.2.0-rc8-syzkaller-00083-g3ac88fa4605e-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023
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