Re: [PATCH 5/5] iommu: Allow default domain type to be set on the kernel command line
On Thu, Jan 26, 2017 at 06:15:55PM +0100, Joerg Roedel wrote: > On Thu, Jan 19, 2017 at 06:19:15PM +, Will Deacon wrote: > > Rather than modify each IOMMU driver to provide different semantics for > > DMA domains, instead we introduce a command line parameter that can be > > used to change the type of the default domain. Passthrough can then be > > specified using "iommu.default_domain=identity" on the kernel command > > line. > > I like the general idea of this, but the above is a terrible name for a > kernel commandline-parameter. The x86 iommus support iommu=pt which is > pretty much the same as this patch does. Happy to bikeshed the name ;) > How about something like "iommu.passthrough=0/1"? And please add the > parameter to the kernel documentation too. Sure, if you think that the identity domain is the only thing we'll ever want to set (so far, it's the only thing people have asked me for). Will ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
Re: [PATCH 5/5] iommu: Allow default domain type to be set on the kernel command line
On 26/01/17 17:15, Joerg Roedel wrote: > On Thu, Jan 19, 2017 at 06:19:15PM +, Will Deacon wrote: >> Rather than modify each IOMMU driver to provide different semantics for >> DMA domains, instead we introduce a command line parameter that can be >> used to change the type of the default domain. Passthrough can then be >> specified using "iommu.default_domain=identity" on the kernel command >> line. > > I like the general idea of this, but the above is a terrible name for a > kernel commandline-parameter. The x86 iommus support iommu=pt which is > pretty much the same as this patch does. Indeed, I was keen on making "iommu=pt" also do this default domain switch itself so we wouldn't need a new option - it didn't *appear* that that would break the AMD driver (as the only other default domain user supporting identity domains) but I may have overlooked something. Robin. > How about something like "iommu.passthrough=0/1"? And please add the > parameter to the kernel documentation too. > > > Joerg > ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
Re: [PATCH 5/5] iommu: Allow default domain type to be set on the kernel command line
On Thu, Jan 19, 2017 at 06:19:15PM +, Will Deacon wrote: > Rather than modify each IOMMU driver to provide different semantics for > DMA domains, instead we introduce a command line parameter that can be > used to change the type of the default domain. Passthrough can then be > specified using "iommu.default_domain=identity" on the kernel command > line. I like the general idea of this, but the above is a terrible name for a kernel commandline-parameter. The x86 iommus support iommu=pt which is pretty much the same as this patch does. How about something like "iommu.passthrough=0/1"? And please add the parameter to the kernel documentation too. Joerg ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
