From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933488Ab2AIWsV (ORCPT ); Mon, 9 Jan 2012 17:48:21 -0500 Received: from mail-ey0-f174.google.com ([209.85.215.174]:56064 "EHLO mail-ey0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933258Ab2AIWsU (ORCPT ); Mon, 9 Jan 2012 17:48:20 -0500 Date: Tue, 10 Jan 2012 01:44:36 +0300 From: Sergey Senozhatsky To: Alexander Viro Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] block_dev: Suppress bdev_cache_init() kmemleak warninig Message-ID: <20120109224436.GA3429@swordfish> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org block_dev: Suppress bdev_cache_init() kmemleak warninig Kmemleak reports the following warning in bdev_cache_init() [ 0.003738] kmemleak: Object 0xffff880153035200 (size 256): [ 0.003823] kmemleak: comm "swapper/0", pid 0, jiffies 4294667299 [ 0.003909] kmemleak: min_count = 1 [ 0.003988] kmemleak: count = 0 [ 0.004066] kmemleak: flags = 0x1 [ 0.004144] kmemleak: checksum = 0 [ 0.004224] kmemleak: backtrace: [ 0.004303] [] kmemleak_alloc+0x21/0x3e [ 0.004446] [] kmem_cache_alloc+0xca/0x1dc [ 0.004592] [] alloc_vfsmnt+0x1f/0x198 [ 0.004736] [] vfs_kern_mount+0x36/0xd2 [ 0.004879] [] kern_mount_data+0x18/0x32 [ 0.005025] [] bdev_cache_init+0x51/0x81 [ 0.005169] [] vfs_caches_init+0x101/0x10d [ 0.005313] [] start_kernel+0x344/0x383 [ 0.005456] [] x86_64_start_reservations+0xae/0xb2 [ 0.005602] [] x86_64_start_kernel+0x102/0x111 [ 0.005747] [] 0xffffffffffffffff [ 0.008653] kmemleak: Trying to color unknown object at 0xffff880153035220 as Grey [ 0.008754] Pid: 0, comm: swapper/0 Not tainted 3.3.0-rc0-dbg-04200-g8180888-dirty #888 [ 0.008856] Call Trace: [ 0.008934] [] ? find_and_get_object+0x44/0x118 [ 0.009023] [] paint_ptr+0x57/0x8f [ 0.009109] [] kmemleak_not_leak+0x23/0x42 [ 0.009195] [] bdev_cache_init+0x72/0x81 [ 0.009282] [] vfs_caches_init+0x101/0x10d [ 0.009368] [] start_kernel+0x344/0x383 [ 0.009466] [] x86_64_start_reservations+0xae/0xb2 [ 0.009555] [] ? early_idt_handlers+0x140/0x140 [ 0.009643] [] x86_64_start_kernel+0x102/0x111 due to attempt to mark pointer to `struct vfsmount' as a gray object, which is embedded into `struct mount' returned from alloc_vfsmnt(). Pass actual allocated `struct mount' pointer to kmemleak_not_leak() instead. Signed-off-by: Sergey Senozhatsky --- diff --git a/fs/block_dev.c b/fs/block_dev.c index 69a5b6f..60589ef 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -29,6 +29,7 @@ #include #include #include "internal.h" +#include "mount.h" struct bdev_inode { struct block_device bdev; @@ -522,6 +523,7 @@ void __init bdev_cache_init(void) { int err; struct vfsmount *bd_mnt; + struct mount *mnt; bdev_cachep = kmem_cache_create("bdev_cache", sizeof(struct bdev_inode), 0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| @@ -534,11 +536,12 @@ void __init bdev_cache_init(void) if (IS_ERR(bd_mnt)) panic("Cannot create bdev pseudo-fs"); /* - * This vfsmount structure is only used to obtain the + * This mount 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 */ + mnt = container_of(bd_mnt, struct mount, mnt); + kmemleak_not_leak(mnt); + blockdev_superblock = bd_mnt->mnt_sb; /* For writeback */ } /*