Re: [PATCH v12 3/5] iommu/vt-d: Add support for IOMMU default DMA mode build options

[John Garry]

On 12/06/2021 03:22, Lu Baolu wrote:
> On 2021/6/11 20:20, John Garry wrote:
> > @@ -453,8 +452,7 @@ static int __init intel_iommu_setup(char *str)
> >               pr_warn("intel_iommu=forcedac deprecated; use 
> > iommu.forcedac instead\n");
> >               iommu_dma_forcedac = true;
> >           } else if (!strncmp(str, "strict", 6)) {
> > -            pr_info("Disable batched IOTLB flush\n");
> > -            intel_iommu_strict = 1;
> > +            iommu_set_dma_strict(true);
>
> I would like to deprecate this command line and ask users to use
> iommu.strict instead.

ok, but then I should probably make the AMD driver also officially 
support this.

> --- a/drivers/iommu/intel/iommu.c
> +++ b/drivers/iommu/intel/iommu.c
> @@ -436,7 +436,7 @@ static int __init intel_iommu_setup(char *str)
>                          pr_warn("intel_iommu=forcedac deprecated; use 
> iommu.forcedac instead\n");
>                          iommu_dma_forcedac = true;
>                  } else if (!strncmp(str, "strict", 6)) {
> -                       pr_info("Disable batched IOTLB flush\n");
> +                       pr_warn("intel_iommu=strict deprecated; use 
> iommu.strict instead\n");
>                          intel_iommu_strict = 1;
>
> Also update Documentation/admin-guide/kernel-parameters.txt accordingly.

Thanks,
John