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BUG: KCSAN: data-race in __anon_vma_prepare / handle_mm_fault

write to 0xffff888104217100 of 8 bytes by task 4236 on cpu 1:
 __anon_vma_prepare+0x172/0x2f0 mm/rmap.c:213
 __vmf_anon_prepare mm/memory.c:3506 [inline]
 vmf_anon_prepare mm/internal.h:432 [inline]
 do_anonymous_page mm/memory.c:5050 [inline]
 do_pte_missing mm/memory.c:4232 [inline]
 handle_pte_fault mm/memory.c:6052 [inline]
 __handle_mm_fault mm/memory.c:6195 [inline]
 handle_mm_fault+0x1d58/0x2c20 mm/memory.c:6364
 do_user_addr_fault+0x3fe/0x1090 arch/x86/mm/fault.c:1387
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
 rep_movs_alternative+0x11/0x90 arch/x86/lib/copy_user_64.S:46
 copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline]
 raw_copy_to_user arch/x86/include/asm/uaccess_64.h:147 [inline]
 _inline_copy_to_user include/linux/uaccess.h:197 [inline]
 _copy_to_user+0x7c/0xa0 lib/usercopy.c:26
 copy_to_user include/linux/uaccess.h:225 [inline]
 do_timer_create+0x667/0x990 kernel/time/posix-timers.c:533
 __do_sys_timer_create kernel/time/posix-timers.c:-1 [inline]
 __se_sys_timer_create kernel/time/posix-timers.c:574 [inline]
 __x64_sys_timer_create+0xb9/0xe0 kernel/time/posix-timers.c:574
 x64_sys_call+0x29d7/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:223
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888104217100 of 8 bytes by task 4235 on cpu 0:
 __vmf_anon_prepare mm/memory.c:3500 [inline]
 vmf_anon_prepare mm/internal.h:432 [inline]
 do_anonymous_page mm/memory.c:5050 [inline]
 do_pte_missing mm/memory.c:4232 [inline]
 handle_pte_fault mm/memory.c:6052 [inline]
 __handle_mm_fault mm/memory.c:6195 [inline]
 handle_mm_fault+0xe8e/0x2c20 mm/memory.c:6364
 do_user_addr_fault+0x636/0x1090 arch/x86/mm/fault.c:1336
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

value changed: 0x0000000000000000 -> 0xffff888103cf2e38

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 4235 Comm: syz.4.255 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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