1 files changed, 31 insertions, 0 deletions

diff --git a/drivers/char/sysrq.c b/drivers/char/sysrq.c
index 8fdfe9c871e3..dce4cc0e6953 100644
--- a/drivers/char/sysrq.c
+++ b/drivers/char/sysrq.c
@@ -23,6 +23,7 @@
 #include <linux/reboot.h>
 #include <linux/sysrq.h>
 #include <linux/kbd_kern.h>
+#include <linux/proc_fs.h>
 #include <linux/quotaops.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
@@ -326,6 +327,7 @@ static struct sysrq_key_op sysrq_moom_op = {
         .handler        = sysrq_handle_moom,
         .help_msg       = "Full",
         .action_msg     = "Manual OOM execution",
+        .enable_mask    = SYSRQ_ENABLE_SIGNAL,
 };
 
 static void sysrq_handle_kill(int key, struct tty_struct *tty)
@@ -533,3 +535,32 @@ int unregister_sysrq_key(int key, struct sysrq_key_op *op_p)
         return __sysrq_swap_key_ops(key, NULL, op_p);
 }
 EXPORT_SYMBOL(unregister_sysrq_key);
+
+#ifdef CONFIG_PROC_FS
+/*
+ * writing 'C' to /proc/sysrq-trigger is like sysrq-C
+ */
+static ssize_t write_sysrq_trigger(struct file *file, const char __user *buf,
+                                   size_t count, loff_t *ppos)
+{
+        if (count) {
+                char c;
+
+                if (get_user(c, buf))
+                        return -EFAULT;
+                __handle_sysrq(c, NULL, 0);
+        }
+        return count;
+}
+
+static const struct file_operations proc_sysrq_trigger_operations = {
+        .write          = write_sysrq_trigger,
+};
+
+static int __init sysrq_init(void)
+{
+        proc_create("sysrq-trigger", S_IWUSR, NULL, &proc_sysrq_trigger_operations);
+        return 0;
+}
+module_init(sysrq_init);
+#endif