diff --git a/kernel_module/seq_file.c b/kernel_module/seq_file.c
index 3078273..e269904 100644
--- a/kernel_module/seq_file.c
+++ b/kernel_module/seq_file.c
@@ -31,7 +31,7 @@ Bibliography:
 #include <linux/module.h>
 #include <linux/printk.h> /* pr_info */
 #include <linux/seq_file.h> /* seq_read, seq_lseek, single_release */
-#include <linux/slab.h>
+#include <linux/slab.h> /* kmalloc, kfree */
 #include <uapi/linux/stat.h> /* S_IRUSR */
 
 static int max = 2;
diff --git a/kernel_module/virt_to_phys.c b/kernel_module/virt_to_phys.c
index 391d4db..0a7b234 100644
--- a/kernel_module/virt_to_phys.c
+++ b/kernel_module/virt_to_phys.c
@@ -7,6 +7,10 @@ and on QEMU monitor:
 
 	xp 0x<vaddr>
 
+x86 docs say it only works for kmalloc.
+
+static inline phys_addr_t virt_to_phys(volatile void *address)
+
 - https://stackoverflow.com/questions/5748492/is-there-any-api-for-determining-the-physical-address-from-virtual-address-in-li
 - https://stackoverflow.com/questions/43325205/can-we-use-virt-to-phys-for-user-space-memory-in-kernel-module
 */
@@ -18,20 +22,21 @@ and on QEMU monitor:
 #include <linux/kthread.h>
 #include <linux/module.h>
 #include <linux/seq_file.h> /* single_open, single_release */
+#include <linux/slab.h> /* kmalloc, kfree */
 
-static volatile u32 i = 0x12345678;
+static volatile u32 *i;
 
 static struct dentry *debugfs_file;
 
 static int show(struct seq_file *m, void *v)
 {
 	seq_printf(m,
-		"i 0x%llx\n"
-		"&i %p\n"
+		"*i 0x%llx\n"
+		"i %p\n"
 		"virt_to_phys 0x%llx\n",
-		(unsigned long long)i,
-		&i,
-		(unsigned long long)virt_to_phys(&i)
+		(unsigned long long)*i,
+		i,
+		(unsigned long long)virt_to_phys((void *)i)
 	);
 	return 0;
 }
@@ -51,6 +56,8 @@ static const struct file_operations fops = {
 
 static int myinit(void)
 {
+ 	i = kmalloc(sizeof(loff_t), GFP_KERNEL);
+ 	*i = 0x12345678;
 	debugfs_file = debugfs_create_file(
 		"lkmc_virt_to_phys", S_IRUSR, NULL, NULL, &fops);
 	return 0;
@@ -59,6 +66,7 @@ static int myinit(void)
 static void myexit(void)
 {
 	debugfs_remove(debugfs_file);
+	kfree((void *)i);
 }
 
 module_init(myinit)
diff --git a/rootfs_overlay/virt_to_phys.sh b/rootfs_overlay/virt_to_phys.sh
index 727cc3a..2eaa9f4 100755
--- a/rootfs_overlay/virt_to_phys.sh
+++ b/rootfs_overlay/virt_to_phys.sh
@@ -1,8 +1,10 @@
 #!/bin/sh
 set -ex
 insmod /virt_to_phys.ko
-cat /sys/kernel/debug/lkmc_virt_to_phys
-addr=$(grep virt_to_phys /sys/kernel/debug/lkmc_virt_to_phys | cut -d ' ' -f 2)
+cd /sys/kernel/debug
+cat lkmc_virt_to_phys
+addr=$(grep virt_to_phys lkmc_virt_to_phys | cut -d ' ' -f 2)
 devmem2 "$addr"
-devmem2 "$addr" w 0x87654321
+devmem2 "$addr" w 0x9ABCDEF0
+cat lkmc_virt_to_phys
 rmmod virt_to_phys