CachedAppOptimizer: Fix FULL memcg compaction validation - #1338
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neobuddy89 merged 1 commit intoAug 1, 2026
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Compaction flags are used as a bitmask, with FILE set to 1 and ANON set to 2. FULL therefore has the value 3. compactionFlagsValidForMemcg() uses the flags directly as an index, but its cache only has three entries, causing FULL compaction to be rejected as invalid and crash system_server. Size the cache from the maximum valid flag combination so all valid values from NONE through FULL can be cached. Fixes: 4ec6b89 ("CachedAppOptimizer: Fallback to process_madvise when memcg doesn't support compaction")
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Compaction flags are used as a bitmask, with FILE set to 1 and ANON set to 2. FULL therefore has the value 3.
compactionFlagsValidForMemcg() uses the flags directly as an index, but its cache only has three entries, causing FULL compaction to be rejected as invalid and crash system_server.
Size the cache from the maximum valid flag combination so all valid values from NONE through FULL can be cached.
Fixes: 4ec6b89 ("CachedAppOptimizer: Fallback to process_madvise when memcg doesn't support compaction")