Re: [PATCH v2 6/6] powerpc/pseries/iommu: Avoid errors when DDW starts at 0x00
On Wed, 2020-07-01 at 18:04 +1000, Alexey Kardashevskiy wrote: > > On 27/06/2020 03:46, Leonardo Bras wrote: > > On Wed, 2020-06-24 at 03:24 -0300, Leonardo Bras wrote: > > > As of today, enable_ddw() will return a non-null DMA address if the > > > created DDW maps the whole partition. If the address is valid, > > > iommu_bypass_supported_pSeriesLP() will consider iommu bypass enabled. > > > > > > This can cause some trouble if the DDW happens to start at 0x00. > > > > > > Instead if checking if the address is non-null, check directly if > > > the DDW maps the whole partition, so it can bypass iommu. > > > > > > Signed-off-by: Leonardo Bras > > > > This patch has a bug in it. I will rework it soon. > > I'd rather suggest this: > > https://patchwork.ozlabs.org/project/linuxppc-dev/patch/20180725095032.2196-2-...@ozlabs.ru/ > > Although it does not look like you are actually going to have windows > starting at 0. Thanks, Yeah, agree. I am thinking of dropping this one, as I don't see much good to be done here. Thank you!
Re: [PATCH v2 6/6] powerpc/pseries/iommu: Avoid errors when DDW starts at 0x00
On 27/06/2020 03:46, Leonardo Bras wrote: > On Wed, 2020-06-24 at 03:24 -0300, Leonardo Bras wrote: >> As of today, enable_ddw() will return a non-null DMA address if the >> created DDW maps the whole partition. If the address is valid, >> iommu_bypass_supported_pSeriesLP() will consider iommu bypass enabled. >> >> This can cause some trouble if the DDW happens to start at 0x00. >> >> Instead if checking if the address is non-null, check directly if >> the DDW maps the whole partition, so it can bypass iommu. >> >> Signed-off-by: Leonardo Bras > > This patch has a bug in it. I will rework it soon. I'd rather suggest this: https://patchwork.ozlabs.org/project/linuxppc-dev/patch/20180725095032.2196-2-...@ozlabs.ru/ Although it does not look like you are actually going to have windows starting at 0. Thanks, > Please keep reviewing patches 1-5. > > Best regards, > Leonardo > -- Alexey
Re: [PATCH v2 6/6] powerpc/pseries/iommu: Avoid errors when DDW starts at 0x00
On Wed, 2020-06-24 at 03:24 -0300, Leonardo Bras wrote: > As of today, enable_ddw() will return a non-null DMA address if the > created DDW maps the whole partition. If the address is valid, > iommu_bypass_supported_pSeriesLP() will consider iommu bypass enabled. > > This can cause some trouble if the DDW happens to start at 0x00. > > Instead if checking if the address is non-null, check directly if > the DDW maps the whole partition, so it can bypass iommu. > > Signed-off-by: Leonardo Bras This patch has a bug in it. I will rework it soon. Please keep reviewing patches 1-5. Best regards, Leonardo