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BUG: KCSAN: data-race in isolate_migratepages_block / isolate_migratepages_block

write to 0xffff88823fffa658 of 8 bytes by task 14808 on cpu 0:
 update_cached_migrate mm/compaction.c:450 [inline]
 isolate_migratepages_block+0x1aec/0x1cc0 mm/compaction.c:1311
 isolate_migratepages mm/compaction.c:2177 [inline]
 compact_zone+0x1bd9/0x2790 mm/compaction.c:2668
 compact_node mm/compaction.c:2945 [inline]
 compact_nodes mm/compaction.c:2967 [inline]
 sysctl_compaction_handler+0x2e9/0x550 mm/compaction.c:3018
 proc_sys_call_handler+0x2ec/0x4a0 fs/proc/proc_sysctl.c:600
 proc_sys_write+0x22/0x30 fs/proc/proc_sysctl.c:626
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x57f/0x9a0 fs/read_write.c:687
 ksys_write+0xdc/0x1a0 fs/read_write.c:739
 __do_sys_write fs/read_write.c:750 [inline]
 __se_sys_write fs/read_write.c:747 [inline]
 __x64_sys_write+0x40/0x50 fs/read_write.c:747
 x64_sys_call+0x154e/0x2550 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88823fffa658 of 8 bytes by task 14813 on cpu 1:
 update_cached_migrate mm/compaction.c:449 [inline]
 isolate_migratepages_block+0x1ac8/0x1cc0 mm/compaction.c:1311
 isolate_migratepages mm/compaction.c:2177 [inline]
 compact_zone+0x1bd9/0x2790 mm/compaction.c:2668
 compact_node mm/compaction.c:2945 [inline]
 compact_nodes mm/compaction.c:2967 [inline]
 sysctl_compaction_handler+0x2e9/0x550 mm/compaction.c:3018
 proc_sys_call_handler+0x2ec/0x4a0 fs/proc/proc_sysctl.c:600
 proc_sys_write+0x22/0x30 fs/proc/proc_sysctl.c:626
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x57f/0x9a0 fs/read_write.c:687
 ksys_write+0xdc/0x1a0 fs/read_write.c:739
 __do_sys_write fs/read_write.c:750 [inline]
 __se_sys_write fs/read_write.c:747 [inline]
 __x64_sys_write+0x40/0x50 fs/read_write.c:747
 x64_sys_call+0x154e/0x2550 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x000000000005dc00 -> 0x000000000005e000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 14813 Comm: syz.7.2766 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
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