On Fri, Sep 28, 2012 at 02:23:55PM +0200, Joerg Roedel wrote:
> When the IOMMU is enabled very early (as with irq-remapping)
> some devices are still in BIOS hand. When dma is blocked
> early this can cause lots of IO_PAGE_FAULTs. So delay the
> DMA initialization and do it right before the dma_ops are
> initialized.
> To be secure, block all interrupts by default when irq-remapping is
What are you trying to be secure against?
> enabled in the system. They will be reenabled on demand
> later.
>
> Signed-off-by: Joerg Roedel <joerg.roe...@amd.com>
> ---
> drivers/iommu/amd_iommu_init.c | 19 ++++++++++++++++++-
> 1 file changed, 18 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
> index 3f0b68f..8e9d71c 100644
> --- a/drivers/iommu/amd_iommu_init.c
> +++ b/drivers/iommu/amd_iommu_init.c
> @@ -1378,7 +1378,7 @@ static int __init init_memory_definitions(struct
> acpi_table_header *table)
> * Init the device table to not allow DMA access for devices and
> * suppress all page faults
> */
> -static void init_device_table(void)
> +static void init_device_table_dma(void)
> {
> u32 devid;
>
> @@ -1388,6 +1388,17 @@ static void init_device_table(void)
> }
> }
>
> +static void init_device_table(void)
> +{
> + u32 devid;
> +
> + if (!amd_iommu_irq_remap)
> + return;
> +
> + for (devid = 0; devid <= amd_iommu_last_bdf; ++devid)
> + set_dev_entry_bit(devid, DEV_ENTRY_IRQ_TBL_EN);
> +}
> +
> static void iommu_init_flags(struct amd_iommu *iommu)
> {
> iommu->acpi_flags & IVHD_FLAG_HT_TUN_EN_MASK ?
> @@ -1778,8 +1789,14 @@ static bool detect_ivrs(void)
>
> static int amd_iommu_init_dma(void)
> {
> + struct amd_iommu *iommu;
> int ret;
>
> + init_device_table_dma();
> +
> + for_each_iommu(iommu)
> + iommu_flush_all_caches(iommu);
> +
> if (iommu_pass_through)
> ret = amd_iommu_init_passthrough();
> else
> --
> 1.7.9.5
>
>
> _______________________________________________
> iommu mailing list
> io...@lists.linux-foundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/iommu
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