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BUG: KCSAN: data-race in __anon_vma_prepare / do_anonymous_page

write to 0xffff888101dc9988 of 8 bytes by task 6042 on cpu 0:
 __anon_vma_prepare+0x130/0x2c0 mm/rmap.c:208
 anon_vma_prepare include/linux/rmap.h:149 [inline]
 do_anonymous_page+0x7ae/0x8d0 mm/memory.c:3758
 handle_pte_fault mm/memory.c:4549 [inline]
 __handle_mm_fault mm/memory.c:4686 [inline]
 handle_mm_fault+0x814/0x1590 mm/memory.c:4784
 do_user_addr_fault+0x609/0xbe0 arch/x86/mm/fault.c:1397
 handle_page_fault arch/x86/mm/fault.c:1485 [inline]
 exc_page_fault+0x91/0x290 arch/x86/mm/fault.c:1541
 asm_exc_page_fault+0x1e/0x30
 __put_user_nocheck_4+0x3/0x11
 n_tty_ioctl+0x65/0x1f0 drivers/tty/n_tty.c:2411
 tty_ioctl+0xaf5/0x1130 drivers/tty/tty_io.c:2814
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:860
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888101dc9988 of 8 bytes by task 6039 on cpu 1:
 anon_vma_prepare include/linux/rmap.h:146 [inline]
 do_anonymous_page+0x12c/0x8d0 mm/memory.c:3758
 handle_pte_fault mm/memory.c:4549 [inline]
 __handle_mm_fault mm/memory.c:4686 [inline]
 handle_mm_fault+0x814/0x1590 mm/memory.c:4784
 do_user_addr_fault+0x609/0xbe0 arch/x86/mm/fault.c:1397
 handle_page_fault arch/x86/mm/fault.c:1485 [inline]
 exc_page_fault+0x91/0x290 arch/x86/mm/fault.c:1541
 asm_exc_page_fault+0x1e/0x30

value changed: 0x0000000000000000 -> 0xffff8881014a83c0

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 6039 Comm: syz-executor.1 Not tainted 5.16.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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