On Tue, May 20, 2014 at 08:37:48PM +0800, Yijing Wang wrote:
> Move up the no_iommu and dmar_disabled check, avoid the
> useless initialization for dmar.
>
> Signed-off-by: Yijing Wang <wangyij...@huawei.com>
> ---
> drivers/iommu/intel-iommu.c | 6 +++---
> 1 files changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
> index e020dcf..6b71608 100644
> --- a/drivers/iommu/intel-iommu.c
> +++ b/drivers/iommu/intel-iommu.c
> @@ -3948,6 +3948,9 @@ int __init intel_iommu_init(void)
> /* VT-d is required for a TXT/tboot launch, so enforce that */
> force_on = tboot_force_iommu();
>
> + if (no_iommu || dmar_disabled)
> + return ret;
> +
> if (iommu_init_mempool()) {
> if (force_on)
> panic("tboot: Failed to initialize iommu memory\n");
> @@ -3974,9 +3977,6 @@ int __init intel_iommu_init(void)
> goto out_free_dmar;
> }
>
> - if (no_iommu || dmar_disabled)
> - goto out_free_dmar;
> -
> if (list_empty(&dmar_rmrr_units))
> printk(KERN_INFO "DMAR: No RMRR found\n");
This breaks the kexec case were the old kernel had VT-d enabled and the
new one disabled. In this case the new kernel might need to disable the
IOMMUs.
Joerg
--
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/
