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-rw-r--r--drivers/char/mem.c12
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index b08dc50f9f26..591366baa53e 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -10,6 +10,7 @@
*/
#include <linux/mm.h>
+#include <linux/moduleparam.h>
#include <linux/miscdevice.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
@@ -36,6 +37,7 @@
# include <linux/efi.h>
#endif
+#define DEVMEM_MINOR 1
#define DEVPORT_MINOR 4
static inline unsigned long size_inside_page(unsigned long start,
@@ -913,6 +915,12 @@ static char *mem_devnode(struct device *dev, umode_t *mode)
return NULL;
}
+#ifdef CONFIG_DEVMEM_BOOTPARAM
+static bool devmem;
+module_param(devmem, bool, 0444);
+MODULE_PARM_DESC(devmem, "kernel parameter to activate /dev/mem");
+#endif
+
static struct class *mem_class;
static int __init chr_dev_init(void)
@@ -931,6 +939,10 @@ static int __init chr_dev_init(void)
if (!devlist[minor].name)
continue;
+#ifdef CONFIG_DEVMEM_BOOTPARAM
+ if (minor == DEVMEM_MINOR && !devmem)
+ continue;
+#endif
/*
* Create /dev/port?
*/
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