xtensa: mmu: Fix possible race condition on tlb shootdown

We need to use the mmu spin lock when invalidating the cache during
tlb shootdown, otherwise it is possible that this happens when another
thread is updating the page tables.

Signed-off-by: Flavio Ceolin <[email protected]>
Signed-off-by: Anas Nashif <[email protected]>

Author: Flavio Ceolin

arch/xtensa/core/xtensa_mmu.c

@@ -828,11 +828,13 @@ void z_xtensa_mmu_tlb_shootdown(void)
 	 */
 	key = arch_irq_lock();
 
-	/* We don't have information on which page tables have changed,
-	 * so we just invalidate the cache for all L1 page tables.
-	 */
-	sys_cache_data_invd_range((void *)l1_page_table, sizeof(l1_page_table));
-	sys_cache_data_invd_range((void *)l2_page_tables, sizeof(l2_page_tables));
+	K_SPINLOCK(&xtensa_mmu_lock) {
+		/* We don't have information on which page tables have changed,
+		 * so we just invalidate the cache for all L1 page tables.
+		 */
+		sys_cache_data_invd_range((void *)l1_page_table, sizeof(l1_page_table));
+		sys_cache_data_invd_range((void *)l2_page_tables, sizeof(l2_page_tables));
+	}
 
 #ifdef CONFIG_USERSPACE
 	struct k_thread *thread = _current_cpu->current;