From c05d268cfabbe26d032d73abcea6dc921c49e549 Mon Sep 17 00:00:00 2001 From: Joel Hestness Date: Tue, 29 Sep 2015 09:28:26 -0500 Subject: [PATCH] ruby: Fix CacheMemory allocate leak If a cache entry permission was previously set to NotPresent, but the entry was not deleted, a following cache allocation can cause the entry to be leaked by setting the entry pointer to a newly allocated entry. To eliminate this possibility, check if the new entry is different from the old one, and if so, delete the old one. --- src/mem/ruby/structures/CacheMemory.cc | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/src/mem/ruby/structures/CacheMemory.cc b/src/mem/ruby/structures/CacheMemory.cc index b0e54ec99..6e4022ea6 100644 --- a/src/mem/ruby/structures/CacheMemory.cc +++ b/src/mem/ruby/structures/CacheMemory.cc @@ -263,6 +263,13 @@ CacheMemory::allocate(Addr address, AbstractCacheEntry *entry, bool touch) std::vector &set = m_cache[cacheSet]; for (int i = 0; i < m_cache_assoc; i++) { if (!set[i] || set[i]->m_Permission == AccessPermission_NotPresent) { + if (set[i] && (set[i] != entry)) { + warn_once("This protocol contains a cache entry handling bug: " + "Entries in the cache should never be NotPresent! If\n" + "this entry (%#x) is not tracked elsewhere, it will memory " + "leak here. Fix your protocol to eliminate these!", + address); + } set[i] = entry; // Init entry set[i]->m_Address = address; set[i]->m_Permission = AccessPermission_Invalid; -- 2.30.2