From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shuah Khan Subject: [PATCH] amd_iommu: IO_PAGE_FAULTs on unity mapped regions during amd_iommu_init() Date: Wed, 06 Feb 2013 19:45:28 -0700 Message-ID: <1360205128.2615.14.camel@lorien2> Reply-To: shuah.khan@hp.com Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Sender: stable-owner@vger.kernel.org To: Joerg Roedel Cc: iommu@lists.linux-foundation.org, stable , Greg KH , shuahkhan@gmail.com List-Id: iommu@lists.linux-foundation.org When dma_ops are initialized the unity mappings are created. The init_device_table_dma() function makes sure DMA from all devices is blocked by default. This opens a short window in time where DMA to unity mapped regions is blocked by the IOMMU. Make sure this does not happen by initializing the device table after dma_ops. Signed-off-by: Shuah Khan CC: stable@vger.kernel.org 3.4 --- drivers/iommu/amd_iommu_init.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c index ef0ae93..b573f80 100644 --- a/drivers/iommu/amd_iommu_init.c +++ b/drivers/iommu/amd_iommu_init.c @@ -1572,8 +1572,6 @@ int __init amd_iommu_init_hardware(void) if (amd_iommu_pd_alloc_bitmap == NULL) goto free; - /* init the device table */ - init_device_table(); /* * let all alias entries point to itself @@ -1655,6 +1653,7 @@ out: */ static int __init amd_iommu_init(void) { + struct amd_iommu *iommu; int ret = 0; ret = amd_iommu_init_hardware(); @@ -1673,6 +1672,12 @@ static int __init amd_iommu_init(void) if (ret) goto free; + /* init the device table */ + init_device_table(); + + for_each_iommu(iommu) + iommu_flush_all_caches(iommu); + amd_iommu_init_api(); x86_platform.iommu_shutdown = disable_iommus; -- 1.7.9.5