When a device driver issues the first dma_map command for a device, we assign a new and empty page-table, thus removing all mappings from the old kernel for the device.
Signed-off-by: Li, Zhen-Hua <zhen-h...@hp.com> --- drivers/iommu/intel-iommu.c | 27 ++++++++++++++++++++------- 1 file changed, 20 insertions(+), 7 deletions(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 4837ce5..f11a9b1 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -3200,15 +3200,28 @@ static struct dmar_domain *__get_valid_domain_for_dev(struct device *dev) } /* make sure context mapping is ok */ - if (unlikely(!domain_context_mapped(dev))) { - ret = domain_context_mapping(domain, dev, CONTEXT_TT_MULTI_LEVEL); - if (ret) { - printk(KERN_ERR "Domain context map for %s failed", - dev_name(dev)); - return NULL; - } + if (likely(domain_context_mapped(dev))) { +#ifdef CONFIG_CRASH_DUMP + if (is_kdump_kernel()) { + domain_exit(domain); + domain = get_domain_for_dev(dev, + DEFAULT_DOMAIN_ADDRESS_WIDTH); + if (!domain) { + pr_err("Allocating domain for %s failed", + dev_name(dev)); + return NULL; + } + } else +#endif + return domain; } + ret = domain_context_mapping(domain, dev, CONTEXT_TT_MULTI_LEVEL); + if (ret) { + pr_err("Domain context map for %s failed", + dev_name(dev)); + return NULL; + } return domain; } -- 2.0.0-rc0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/