diff --git a/linker/linker_phdr.cpp b/linker/linker_phdr.cpp
index 1ea79f0..85cd949 100644
--- a/linker/linker_phdr.cpp
+++ b/linker/linker_phdr.cpp
@@ -142,8 +142,18 @@
                                       MAYBE_MAP_FLAG((x), PF_R, PROT_READ) | \
                                       MAYBE_MAP_FLAG((x), PF_W, PROT_WRITE))
 
-// Default PMD size for x86_64 and aarch64 (2MB).
-static constexpr size_t kPmdSize = (1UL << 21);
+static const size_t kPageSize = page_size();
+
+/*
+ * Generic PMD size calculation:
+ *    - Each page table (PT) is of size 1 page.
+ *    - Each page table entry (PTE) is of size 64 bits.
+ *    - Each PTE locates one physical page frame (PFN) of size 1 page.
+ *    - A PMD entry locates 1 page table (PT)
+ *
+ *   PMD size = Num entries in a PT * page_size
+ */
+static const size_t kPmdSize = (kPageSize / sizeof(uint64_t)) * kPageSize;
 
 ElfReader::ElfReader()
     : did_read_(false), did_load_(false), fd_(-1), file_offset_(0), file_size_(0), phdr_num_(0),