kmemleak: Remove some of the kmemleak false positives

There are allocations for which the main pointer cannot be found but
they are not memory leaks. This patch fixes some of them. For more
information on false positives, see Documentation/kmemleak.txt.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

diff --git a/drivers/char/vt.c b/drivers/char/vt.c
index 08151d4de489b1471a257b8648d87747139c559e..961c1a788c613e0880c6322ee4d1c9014d120270 100644 (file)
--- a/drivers/char/vt.c
+++ b/drivers/char/vt.c
@@ -104,6 +104,7 @@
 #include <linux/io.h>
 #include <asm/system.h>
 #include <linux/uaccess.h>
+#include <linux/kmemleak.h>
 
 #define MAX_NR_CON_DRIVER 16
 
@@ -2880,6 +2881,12 @@ static int __init con_init(void)
         */
        for (currcons = 0; currcons < MIN_NR_CONSOLES; currcons++) {
                vc_cons[currcons].d = vc = alloc_bootmem(sizeof(struct vc_data));
+               /*
+                * Kmemleak does not track the memory allocated via
+                * alloc_bootmem() but this block contains pointers to
+                * other blocks allocated via kmalloc.
+                */
+               kmemleak_alloc(vc, sizeof(struct vc_data), 1, GFP_ATOMIC);
                INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
                visual_init(vc, currcons, 1);
                vc->vc_screenbuf = (unsigned short *)alloc_bootmem(vc->vc_screenbuf_size);

diff --git a/fs/block_dev.c b/fs/block_dev.c
index f45dbc18dd175891950ddb84fffa2bc6ce0df117..d250f807fd83d67c025e568b68ab21893127006b 100644 (file)
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -25,6 +25,7 @@
 #include <linux/uio.h>
 #include <linux/namei.h>
 #include <linux/log2.h>
+#include <linux/kmemleak.h>
 #include <asm/uaccess.h>
 #include "internal.h"
 
@@ -492,6 +493,11 @@ void __init bdev_cache_init(void)
        bd_mnt = kern_mount(&bd_type);
        if (IS_ERR(bd_mnt))
                panic("Cannot create bdev pseudo-fs");
+       /*
+        * This vfsmount structure is only used to obtain the
+        * blockdev_superblock, so tell kmemleak not to report it.
+        */
+       kmemleak_not_leak(bd_mnt);
        blockdev_superblock = bd_mnt->mnt_sb;   /* For writeback */
 }
 

diff --git a/include/linux/percpu.h b/include/linux/percpu.h
index 1581ff235c7e341f0cc3b43c0ad1663a03b0b027..26fd9d12f050b32a1d766071ab4e3e4fc0a1aeff 100644 (file)
--- a/include/linux/percpu.h
+++ b/include/linux/percpu.h
@@ -86,7 +86,12 @@ struct percpu_data {
        void *ptrs[1];
 };
 
+/* pointer disguising messes up the kmemleak objects tracking */
+#ifndef CONFIG_DEBUG_KMEMLEAK
 #define __percpu_disguise(pdata) (struct percpu_data *)~(unsigned long)(pdata)
+#else
+#define __percpu_disguise(pdata) (struct percpu_data *)(pdata)
+#endif
 
 #define per_cpu_ptr(ptr, cpu)                                          \
 ({                                                                     \