From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-172.mta1.migadu.com (out-172.mta1.migadu.com [95.215.58.172]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5A7202D606 for ; Wed, 28 Feb 2024 09:31:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709112681; cv=none; b=gFR8+1M+L9AQYJk8aetYlI/JGGp5TBfDk71JTidBuOQYEKk09SGm1X2VNGDlRBODQlXLIY9mQINC7OhJHgxaqVuIYQxU0HK3LTbOL1GXE+NKlau98ANV5VHKRzQ3NHAP4TMLFGTIWbyZZrGoCO4Ipxa2Bpb2vWFNckc5SomZUwU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709112681; c=relaxed/simple; bh=ggsQyXDpBQNykNIgrvksbxqVHHrQQxhUfF3Xmc//E30=; h=Message-ID:Date:MIME-Version:Subject:To:References:From: In-Reply-To:Content-Type; b=Bk7sFYddANxaMKZ+6wen+JdIaAkRkQHh/1/K4go5siT00adrRwauMg1uCTtXp4sP/MY2SSM88D10z++7pLDyjbKwTt/YabuwReK0qTNG/Kq3E1x88jgpMZRcyR2K7XZY8UFdjsFl3WNksDTVOPtToaJIxSVdVT0pIzJjhfzB9+g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=FxkUMgHo; arc=none smtp.client-ip=95.215.58.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="FxkUMgHo" Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1709112676; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=kmyL/BrWdx5wm+hWvNvDksX7lVp1tOfJaEY5Dk9iJ0w=; b=FxkUMgHoZ8vP94baYaMWYAKTYOvHCcfPNQOLWsscKf6JV6oUu2rmY/Gae2+2Ktpv5sOrxl aKR1CyClv8PF3fBMdO9dbk249uKOv8/dOeWCZMXP6LuJTWCyD6nPQwI24LshbKBxrjvRPf w9mpzeiZd30A7jC7MU1uyfZboJ8N1OY= Date: Wed, 28 Feb 2024 17:31:06 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH] mm/slab: Fix a kmemleak in kmem_cache_destroy() Content-Language: en-US To: Xiaolei Wang , cl@linux.com, penberg@kernel.org, rientjes@google.com, iamjoonsoo.kim@lge.com, akpm@linux-foundation.org, vbabka@suse.cz, roman.gushchin@linux.dev, 42.hyeyoo@gmail.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20240228030408.2740647-1-xiaolei.wang@windriver.com> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Chengming Zhou In-Reply-To: <20240228030408.2740647-1-xiaolei.wang@windriver.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT On 2024/2/28 11:04, Xiaolei Wang wrote: > For earlier kmem cache creation, slab_sysfs_init() has not been called. > Consequently, kmem_cache_destroy() cannot utilize kobj_type::release to > release the kmem_cache structure. Therefore, tweak kmem_cache_release() > to use slab_kmem_cache_release() for releasing kmem_cache when slab_state > isn't FULL. This will fixes the memory leaks like following: > > unreferenced object 0xffff0000c2d87080 (size 128): > comm "swapper/0", pid 1, jiffies 4294893428 > hex dump (first 32 bytes): > 00 00 00 00 ad 4e ad de ff ff ff ff 6b 6b 6b 6b .....N......kkkk > ff ff ff ff ff ff ff ff b8 ab 48 89 00 80 ff ff.....H..... > backtrace (crc 8819d0f6): > [] kmemleak_alloc+0xb0/0xc4 > [] kmem_cache_alloc_node+0x288/0x3a8 > [] __kmem_cache_create+0x1e4/0x64c > [] kmem_cache_create_usercopy+0x1c4/0x2cc > [] kmem_cache_create+0x1c/0x28 > [] arm_v7s_alloc_pgtable+0x1c0/0x6d4 > [] alloc_io_pgtable_ops+0xe8/0x2d0 > [] arm_v7s_do_selftests+0xe0/0x73c > [] do_one_initcall+0x11c/0x7ac > [] kernel_init_freeable+0x53c/0xbb8 > [] kernel_init+0x24/0x144 > [] ret_from_fork+0x10/0x20 > > Signed-off-by: Xiaolei Wang Looks good to me. And I notice the PARTIAL_NODE state of slab_state is also useless since SLAB removed. Reviewed-by: Chengming Zhou Thanks. > --- > mm/slab_common.c | 8 ++++++-- > mm/slub.c | 6 ++---- > 2 files changed, 8 insertions(+), 6 deletions(-) > > diff --git a/mm/slab_common.c b/mm/slab_common.c > index 238293b1dbe1..b6b35bcdd196 100644 > --- a/mm/slab_common.c > +++ b/mm/slab_common.c > @@ -404,8 +404,12 @@ EXPORT_SYMBOL(kmem_cache_create); > */ > static void kmem_cache_release(struct kmem_cache *s) > { > - sysfs_slab_unlink(s); > - sysfs_slab_release(s); > + if (slab_state >= FULL) { > + sysfs_slab_unlink(s); > + sysfs_slab_release(s); > + } else { > + slab_kmem_cache_release(s); > + } > } > #else > static void kmem_cache_release(struct kmem_cache *s) > diff --git a/mm/slub.c b/mm/slub.c > index 2ef88bbf56a3..9ba59d064b6d 100644 > --- a/mm/slub.c > +++ b/mm/slub.c > @@ -6792,14 +6792,12 @@ static int sysfs_slab_add(struct kmem_cache *s) > > void sysfs_slab_unlink(struct kmem_cache *s) > { > - if (slab_state >= FULL) > - kobject_del(&s->kobj); > + kobject_del(&s->kobj); > } > > void sysfs_slab_release(struct kmem_cache *s) > { > - if (slab_state >= FULL) > - kobject_put(&s->kobj); > + kobject_put(&s->kobj); > } > > /*