kcore: register module area in generic way

Some archs define MODULED_VADDR/MODULES_END which is not in VMALLOC area.
This is handled only in x86-64.  This patch make it more generic.  And we
can use vread/vwrite to access the area.  Fix it.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 18 insertions, 1 deletions

diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c
index 78970e6f715c..c6a5ec731972 100644
--- a/fs/proc/kcore.c
+++ b/fs/proc/kcore.c
@@ -490,7 +490,7 @@ read_kcore(struct file *file, char __user *buffer, size_t buflen, loff_t *fpos)
                 if (m == NULL) {
                         if (clear_user(buffer, tsz))
                                 return -EFAULT;
-                } else if (is_vmalloc_addr((void *)start)) {
+                } else if (is_vmalloc_or_module_addr((void *)start)) {
                         char * elf_buf;
 
                         elf_buf = kzalloc(tsz, GFP_KERNEL);
@@ -586,6 +586,22 @@ static void __init proc_kcore_text_init(void)
 }
 #endif
 
+#if defined(CONFIG_MODULES) && defined(MODULES_VADDR)
+/*
+ * MODULES_VADDR has no intersection with VMALLOC_ADDR.
+ */
+struct kcore_list kcore_modules;
+static void __init add_modules_range(void)
+{
+        kclist_add(&kcore_modules, (void *)MODULES_VADDR,
+                        MODULES_END - MODULES_VADDR, KCORE_VMALLOC);
+}
+#else
+static void __init add_modules_range(void)
+{
+}
+#endif
+
 static int __init proc_kcore_init(void)
 {
         proc_root_kcore = proc_create("kcore", S_IRUSR, NULL,
@@ -595,6 +611,7 @@ static int __init proc_kcore_init(void)
         /* Store vmalloc area */
         kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
                 VMALLOC_END - VMALLOC_START, KCORE_VMALLOC);
+        add_modules_range();
         /* Store direct-map area from physical memory map */
         kcore_update_ram();
         hotplug_memory_notifier(kcore_callback, 0);