Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935107AbbKTLdx (ORCPT ); Fri, 20 Nov 2015 06:33:53 -0500 Received: from mail-wm0-f50.google.com ([74.125.82.50]:33455 "EHLO mail-wm0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934953AbbKTLdw (ORCPT ); Fri, 20 Nov 2015 06:33:52 -0500 Subject: [RFC PATCH v2] iommu/amd: gray the 'irq_remap_table' object for kmemleak To: Joerg Roedel References: <564EFF6A.2050709@profitbricks.com> Cc: iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org From: Michael Wang Message-ID: <564F051E.9010703@profitbricks.com> Date: Fri, 20 Nov 2015 12:33:50 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.3.0 MIME-Version: 1.0 In-Reply-To: <564EFF6A.2050709@profitbricks.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1783 Lines: 52 The kmemleak testing on 3.18.24 show: unreferenced object 0xffff880233ff9010 (size 16): comm "swapper/0", pid 1, jiffies 4294937440 (age 2010.490s) hex dump (first 16 bytes): 0a 0a 00 00 20 00 00 00 00 44 fb 33 02 88 ff ff .... ....D.3.... backtrace: [] create_object+0x10d/0x2d0 [] kmemleak_alloc+0x5b/0xc0 [] kmem_cache_alloc_trace+0xb9/0x160 [] get_irq_table+0x151/0x380 This is caused by the 'irq_lookup_table' was allocated with __get_free_pages() which won't create kmemleak object, thus it's pointers won't be count as referencing 'irq_remap_table' in kmemleak scan. The 'irq_remap_table' won't be freed after initialized, doesn't make sense to check it's leaking. This patch mark the 'irq_remap_table' object as 'gray' to stop the 'false positives' report. Signed-off-by: Michael Wang --- v2: Use kmemleak_not_leak() instead of kmemleak_ignore() since the 'irq_remap_table' itself also contain pointer. drivers/iommu/amd_iommu.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index 8b2be1e..87a1a88 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -3603,6 +3603,7 @@ static struct irq_remap_table *get_irq_table(u16 devid, bool ioapic) } irq_lookup_table[devid] = table; + kmemleak_not_leak(table); set_dte_irq_entry(devid, table); iommu_flush_dte(iommu, devid); if (devid != alias) { -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/