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BUG: KCSAN: data-race in mas_walk / mas_wmb_replace

write to 0xffff8881042b7000 of 8 bytes by task 4039 on cpu 0:
 mte_set_node_dead lib/maple_tree.c:299 [inline]
 mas_put_in_tree lib/maple_tree.c:1579 [inline]
 mas_topiary_replace lib/maple_tree.c:1823 [inline]
 mas_wmb_replace+0x22e/0x1770 lib/maple_tree.c:2083
 mas_wr_store_entry+0x54a7/0x5a90 lib/maple_tree.c:-1
 mas_store_prealloc+0x421/0x670 lib/maple_tree.c:4936
 vma_iter_store_overwrite mm/vma.h:616 [inline]
 vma_iter_store_new mm/vma.h:623 [inline]
 vma_complete+0x3c7/0x850 mm/vma.c:359
 __split_vma+0x592/0x640 mm/vma.c:569
 split_vma mm/vma.c:599 [inline]
 vma_modify+0xb29/0xc80 mm/vma.c:1691
 vma_modify_flags+0x182/0x210 mm/vma.c:1719
 mprotect_fixup+0x3a2/0x680 mm/mprotect.c:789
 do_mprotect_pkey+0x69e/0x950 mm/mprotect.c:967
 __do_sys_mprotect mm/mprotect.c:988 [inline]
 __se_sys_mprotect mm/mprotect.c:985 [inline]
 __x64_sys_mprotect+0x48/0x60 mm/mprotect.c:985
 x64_sys_call+0x2768/0x3020 arch/x86/include/generated/asm/syscalls_64.h:11
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881042b7000 of 8 bytes by task 4041 on cpu 1:
 ma_dead_node lib/maple_tree.c:544 [inline]
 mte_dead_node lib/maple_tree.c:559 [inline]
 mas_start lib/maple_tree.c:1186 [inline]
 mas_state_walk lib/maple_tree.c:2945 [inline]
 mas_walk+0x15c/0x340 lib/maple_tree.c:4366
 lock_vma_under_rcu+0xc9/0x210 mm/mmap_lock.c:304
 do_user_addr_fault+0x237/0x1060 arch/x86/mm/fault.c:1330
 handle_page_fault arch/x86/mm/fault.c:1479 [inline]
 exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595

value changed: 0xffff88811c04cd41 -> 0xffff8881042b7000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 4041 Comm: syz.1.126 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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