diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index ed71b1c305d7..acdec0c67d3b 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c

@@ -469,6 +469,21 @@ void __init mark_linear_text_alias_ro(void)
 			    PAGE_KERNEL_RO);
 }
 
+static bool crash_mem_map __initdata;
+
+static int __init enable_crash_mem_map(char *arg)
+{
+	/*
+	 * Proper parameter parsing is done by reserve_crashkernel(). We only
+	 * need to know if the linear map has to avoid block mappings so that
+	 * the crashkernel reservations can be unmapped later.
+	 */
+	crash_mem_map = false;