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BUG: KCSAN: data-race in compact_zone / compact_zone

write to 0xffff88823fffab98 of 8 bytes by task 10995 on cpu 1:
 compact_zone+0x1e81/0x2720 mm/compaction.c:2642
 compact_zone_order mm/compaction.c:2799 [inline]
 try_to_compact_pages+0x3ca/0x960 mm/compaction.c:2860
 __alloc_pages_direct_compact+0x64/0x3b0 mm/page_alloc.c:4157
 __alloc_pages_slowpath+0x25a/0x600 mm/page_alloc.c:4830
 __alloc_frozen_pages_noprof+0x270/0x350 mm/page_alloc.c:5239
 alloc_pages_mpol+0xb3/0x260 mm/mempolicy.c:2490
 alloc_frozen_pages_noprof mm/mempolicy.c:2561 [inline]
 alloc_pages_noprof+0x8f/0x140 mm/mempolicy.c:2581
 vm_area_alloc_pages mm/vmalloc.c:3728 [inline]
 __vmalloc_area_node mm/vmalloc.c:3878 [inline]
 __vmalloc_node_range_noprof+0xaed/0x11c0 mm/vmalloc.c:4064
 __kvmalloc_node_noprof+0x3d4/0x640 mm/slub.c:6860
 futex_hash_allocate+0x190/0x9a0 kernel/futex/core.c:1815
 futex_hash_prctl+0xd8/0xf0 kernel/futex/core.c:1961
 __do_sys_prctl kernel/sys.c:2885 [inline]
 __se_sys_prctl+0x4f4/0x1400 kernel/sys.c:2534
 __x64_sys_prctl+0x67/0x80 kernel/sys.c:2534
 x64_sys_call+0x2533/0x3020 arch/x86/include/generated/asm/syscalls_64.h:158
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

write to 0xffff88823fffab98 of 8 bytes by task 11022 on cpu 0:
 compact_zone+0x1e81/0x2720 mm/compaction.c:2642
 compact_zone_order mm/compaction.c:2799 [inline]
 try_to_compact_pages+0x3ca/0x960 mm/compaction.c:2860
 __alloc_pages_direct_compact+0x64/0x3b0 mm/page_alloc.c:4157
 __alloc_pages_slowpath+0x25a/0x600 mm/page_alloc.c:4830
 __alloc_frozen_pages_noprof+0x270/0x350 mm/page_alloc.c:5239
 alloc_pages_mpol+0xb3/0x260 mm/mempolicy.c:2490
 alloc_frozen_pages_noprof mm/mempolicy.c:2561 [inline]
 alloc_pages_noprof+0x8f/0x140 mm/mempolicy.c:2581
 vm_area_alloc_pages mm/vmalloc.c:3728 [inline]
 __vmalloc_area_node mm/vmalloc.c:3878 [inline]
 __vmalloc_node_range_noprof+0xaed/0x11c0 mm/vmalloc.c:4064
 __kvmalloc_node_noprof+0x3d4/0x640 mm/slub.c:6860
 futex_hash_allocate+0x190/0x9a0 kernel/futex/core.c:1815
 futex_hash_prctl+0xd8/0xf0 kernel/futex/core.c:1961
 __do_sys_prctl kernel/sys.c:2885 [inline]
 __se_sys_prctl+0x4f4/0x1400 kernel/sys.c:2534
 __x64_sys_prctl+0x67/0x80 kernel/sys.c:2534
 x64_sys_call+0x2533/0x3020 arch/x86/include/generated/asm/syscalls_64.h:158
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000152e00 -> 0x0000000000155600

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 11022 Comm: syz.8.2101 Tainted: G        W           syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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