Messages in this thread | | | From | Sathyanarayanan Kuppuswamy Natarajan <> | Date | Wed, 30 Jun 2021 16:22:06 -0700 | Subject | Re: [PATCH v3 00/11] Add TDX Guest Support (Initial support) |
| |
Hi x86 maintainers,
On Fri, Jun 18, 2021 at 3:58 PM Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> wrote: > > Hi All, > > Intel's Trust Domain Extensions (TDX) protect guest VMs from malicious > hosts and some physical attacks. This series adds the basic TDX guest > infrastructure support (including #VE handler support, and #VE support > for halt and CPUID). This is just a subset of patches in the bare minimum > TDX support patch list which is required for supporting minimal > functional TDX guest. Other basic feature features like #VE support for > IO, MMIO, boot optimization fixes and shared-mm support will be submitted > in a separate patch set. To make reviewing easier we split it into smaller > series. This series alone is not necessarily fully functional. > > Also, the host-side support patches, and support for advanced TD guest > features like attestation or debug-mode will be submitted at a later time. > Also, at this point it is not secure with some known holes in drivers, and > also hasn’t been fully audited and fuzzed yet. > > TDX has a lot of similarities to SEV. It enhances confidentiality and > of guest memory and state (like registers) and includes a new exception > (#VE) for the same basic reasons as SEV-ES. Like SEV-SNP (not merged > yet), TDX limits the host's ability to effect changes in the guest > physical address space. With TDX the host cannot access the guest memory, > so various functionality that would normally be done in KVM has moved > into a (paravirtualized) guest. Partially this is done using the > Virtualization Exception (#VE) and partially with direct paravirtual hooks. > > The TDX architecture also includes a new CPU mode called > Secure-Arbitration Mode (SEAM). The software (TDX module) running in this > mode arbitrates interactions between host and guest and implements many of > the guarantees of the TDX architecture. > > Some of the key differences between TD and regular VM is, > > 1. Multi CPU bring-up is done using the ACPI MADT wake-up table. > 2. A new #VE exception handler is added. The TDX module injects #VE exception > to the guest TD in cases of instructions that need to be emulated, disallowed > MSR accesses, etc. > 3. By default memory is marked as private, and TD will selectively share it with > VMM based on need. > > Note that the kernel will also need to be hardened against low level inputs from > the now untrusted hosts. This will be done in follow on patches. > > You can find TDX related documents in the following link. > > https://software.intel.com/content/www/br/pt/develop/articles/intel-trust-domain-extensions.html > > Changes since v1 (v2 is partial set submission): > * Patch titled "x86/x86: Add early_is_tdx_guest() interface" is moved > out of this series. > * Rest of the change log is added per patch.
I have submitted the following list of TDX patch series 2-3 weeks back, and so far we only received feedback for a few patches in sets 1 and 4 (from Boris & Tom Lendacky). So, I was curious if you were planning on taking a look at other sets of patch series in this submission or were waiting for new revisions? Please let me know your comments.
sets 1-4 are core sets of patches that add TDX guest support. set 4+ adds extra TDX features support.
Add TDX Guest Support (Initial support) [set 1] (currently v3 version) - https://lore.kernel.org/patchwork/project/lkml/list/?series=505232
Add TDX Guest Support (#VE handler support) [set 2] (currently v2 version) - https://lore.kernel.org/patchwork/project/lkml/list/?series=506230
Add TDX Guest Support (boot fixes) [set 3] (currently v2 version) - https://lore.kernel.org/patchwork/project/lkml/list/?series=506231
Add TDX Guest Support (shared-mm support) [set 4] (currently v2 version) - https://lore.kernel.org/patchwork/project/lkml/list/?series=506232
Add TDX Guest Support (Debug support) [set 5] (currently v1 version) - https://lore.kernel.org/patchwork/project/lkml/list/?series=506233
Add TDX Guest Support (Attestation support) [set 6] (currently v1 version) - https://lore.kernel.org/patchwork/project/lkml/list/?series=506234
-- Sathyanarayanan Kuppuswamy Linux Kernel Developer
| |