Re: [dpdk-dev] [PATCH] bus/pci: always check IOMMU capabilities

[David Marchand <david.marchand@redhat.com>]

On Fri, Aug 2, 2019 at 12:14 PM David Marchand
<david.marchand@redhat.com> wrote:
>
> IOMMU capabilities won't change and must be checked even if no PCI device
> seem to be supported yet when EAL initialised.
>
> This is to accommodate with SPDK that registers its drivers after
> rte_eal_init(), especially on PPC platform where the IOMMU does not
> support VA.

David, Takeshi,

Can you test your setups with (only) this patch?
This should address both of your issues.


>
> Fixes: 703458e19c16 ("bus/pci: consider only usable devices for IOVA mode")
>
> Signed-off-by: David Marchand <david.marchand@redhat.com>
> ---
>  drivers/bus/pci/bsd/pci.c    |  6 ++++++
>  drivers/bus/pci/linux/pci.c  | 25 ++++++-------------------
>  drivers/bus/pci/pci_common.c | 16 +++++++++++++++-
>  drivers/bus/pci/private.h    |  5 ++++-
>  4 files changed, 31 insertions(+), 21 deletions(-)
>

[snip]

> diff --git a/drivers/bus/pci/pci_common.c b/drivers/bus/pci/pci_common.c
> index 9794552..8d1d6ab 100644
> --- a/drivers/bus/pci/pci_common.c
> +++ b/drivers/bus/pci/pci_common.c

[snip]

> @@ -643,7 +651,13 @@ rte_pci_get_iommu_class(void)
>                                 devices_want_va = true;
>                 }
>         }
> -       if (devices_want_va && !devices_want_pa) {
> +       if (iommu_no_va == 1) {
> +               iova_mode = RTE_IOVA_PA;
> +               if (devices_want_va) {
> +                       RTE_LOG(WARNING, EAL, "Some devices want 'VA' but because IOMMU does not support 'VA'.\n");

Note to self, s/but because/but/


> +                       RTE_LOG(WARNING, EAL, "The devices that want 'VA' won't initialize.\n");
> +               }
> +       } else if (devices_want_va && !devices_want_pa) {
>                 iova_mode = RTE_IOVA_VA;
>         } else if (devices_want_pa && !devices_want_va) {
>                 iova_mode = RTE_IOVA_PA;


-- 
David Marchand