arch,pt: do not flush entire TLB upon PT change

Use INVLPG instead. Signed-off-by: Pawel Wieczorkiewicz <[email protected]>
KernelTestFramework · Oct 25, 2023 · 9f7ae9c · 9f7ae9c
1 parent 7d6e25f
commit 9f7ae9c
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Showing 2 changed files with 4 additions and 1 deletion.
diff --git a/arch/x86/pagetables.c b/arch/x86/pagetables.c
@@ -107,6 +107,7 @@ void dump_pagetables(cr3_t cr3) {
 static inline void *tmp_map_mfn(mfn_t mfn) {
     BUG_ON(mfn_invalid(mfn));
     set_pgentry(_tmp_mapping_entry, mfn, L1_PROT);
+    invlpg(_tmp_mapping);
     return _tmp_mapping;
 }
 
@@ -199,6 +200,7 @@ static void *_vmap(cr3_t *cr3_ptr, void *va, mfn_t mfn, unsigned int order,
         tab = tmp_map_mfn(l3t_mfn);
         entry = &tab[l3_table_index(va)];
         set_pgentry(entry, mfn, l3_flags | _PAGE_PSE);
+        invlpg(va);
         goto done;
     }
 
@@ -208,6 +210,7 @@ static void *_vmap(cr3_t *cr3_ptr, void *va, mfn_t mfn, unsigned int order,
         tab = tmp_map_mfn(l2t_mfn);
         entry = &tab[l2_table_index(va)];
         set_pgentry(entry, mfn, l2_flags | _PAGE_PSE);
+        invlpg(va);
         goto done;
     }
 
@@ -216,6 +219,7 @@ static void *_vmap(cr3_t *cr3_ptr, void *va, mfn_t mfn, unsigned int order,
     tab = tmp_map_mfn(l1t_mfn);
     entry = &tab[l1_table_index(va)];
     set_pgentry(entry, mfn, l1_flags);
+    invlpg(va);
 
 done:
     spin_unlock(&lock);

diff --git a/include/arch/x86/pagetable.h b/include/arch/x86/pagetable.h
@@ -272,7 +272,6 @@ static inline pdpe_t *get_pdpe(const void *va) {
 static inline void set_pgentry(pgentry_t *e, mfn_t mfn, unsigned long flags) {
     *e = pgentry_from_mfn(mfn, flags);
     barrier();
-    flush_tlb();
 }
 
 /* External declarations */