diff --git a/headers/private/kernel/arch/sparc/arch_kernel.h b/headers/private/kernel/arch/sparc/arch_kernel.h
index 5666fff6b5..10029e071e 100644
--- a/headers/private/kernel/arch/sparc/arch_kernel.h
+++ b/headers/private/kernel/arch/sparc/arch_kernel.h
@@ -9,7 +9,11 @@
 #include <arch/cpu.h>
 
 // memory layout
-#define KERNEL_LOAD_BASE_64_BIT 0xffffffff80000000ll
+// FIXME: On sparc, the kernel should live in an independent address space,
+// and does not share addresses with userspace. So, a lot of this doesn't
+// really make sense. See #19597 for discussion.
+// The consequence is that IS_USER_MEMORY cannot work in the way we need.
+#define KERNEL_LOAD_BASE_64_BIT 0x80000000ll
 
 // Base of the kernel address space.
 // KERNEL_BASE is the base of the kernel address space. This differs from the
diff --git a/src/system/ldscripts/sparc/kernel.ld b/src/system/ldscripts/sparc/kernel.ld
index f465690d66..fb50cdb64e 100644
--- a/src/system/ldscripts/sparc/kernel.ld
+++ b/src/system/ldscripts/sparc/kernel.ld
@@ -13,7 +13,7 @@ PHDRS
 
 SECTIONS
 {
-	. = 0xFFFFFFFF80000000 + SIZEOF_HEADERS;
+	. = 0x80000000 + SIZEOF_HEADERS;
 
 	.interp : { *(.interp) } : text
 	.hash : { *(.hash) }