Skip to content

Snp host latest - #6

Open
MelodyHuibo wants to merge 1985 commits into
AMDESE:snp-host-latestfrom
MelodyHuibo:snp-host-latest
Open

Snp host latest#6
MelodyHuibo wants to merge 1985 commits into
AMDESE:snp-host-latestfrom
MelodyHuibo:snp-host-latest

Conversation

@MelodyHuibo

Copy link
Copy Markdown

No description provided.

andy-shev and others added 30 commits February 20, 2024 13:29
Replace open coded functionalify of kstrdup_and_replace() with a call.

Link: https://lkml.kernel.org/r/20240213162741.3102810-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Found with git grep 'MODULE_AUTHOR(".*([^)]*@'
Fixed with
  sed -i '/MODULE_AUTHOR(".*([^)]*@/{s/ (/ </g;s/)"/>"/;s/)and/> and/}' \
    $(git grep -l 'MODULE_AUTHOR(".*([^)]*@')

Also:
  in drivers/media/usb/siano/smsusb.c normalise ", INC" to ", Inc";
     this is what every other MODULE_AUTHOR for this company says,
     and it's what the header says
  in drivers/sbus/char/openprom.c normalise a double-spaced separator;
     this is clearly copied from the copyright header,
     where the names are aligned on consecutive lines thusly:
      * Linux/SPARC PROM Configuration Driver
      * Copyright (C) 1996 Thomas K. Dyas (tdyas@noc.rutgers.edu)
      * Copyright (C) 1996 Eddie C. Dost  (ecd@skynet.be)
     but the authorship branding is single-line

Link: https://lkml.kernel.org/r/mk3geln4azm5binjjlfsgjepow4o73domjv6ajybws3tz22vb3@tarta.nabijaczleweli.xyz
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Since commit aed65af ("drivers: make device_type const"), the driver
core can properly handle constant struct device_type.  Make sure that new
usages of the struct already enter the tree as const.

Link: https://lkml.kernel.org/r/20240218-device_cleanup-checkpatch-v1-1-8b0b89c4f6b1@marliere.net
Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Bring the PDF build fix into docs-next so we can ... build PDFs
codomania and others added 13 commits February 21, 2024 09:38
While resolving the RMP page fault, there may be cases where the page
level between the RMP entry and TDP does not match and the 2M RMP entry
must be split into 4K RMP entries. Or a 2M TDP page need to be broken
into multiple of 4K pages.

To keep the RMP and TDP page level in sync, zap the gfn range after
splitting the pages in the RMP entry. The zap should force the TDP to
gets rebuilt with the new page level.

Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
Signed-off-by: Michael Roth <michael.roth@amd.com>
When SEV-SNP is enabled in the guest, the hardware places restrictions
on all memory accesses based on the contents of the RMP table. When
hardware encounters RMP check failure caused by the guest memory access
it raises the #NPF. The error code contains additional information on
the access type. See the APM volume 2 for additional information.

When using gmem, RMP faults resulting from mismatches between the state
in the RMP table vs. what the guest expects via its page table result
in KVM_EXIT_MEMORY_FAULTs being forwarded to userspace to handle. This
means the only expected case that needs to be handled in the kernel is
when the page size of the entry in the RMP table is larger than the
mapping in the nested page table, in which case a PSMASH instruction
needs to be issued to split the large RMP entry into individual 4K
entries so that subsequent accesses can succeed.

Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Co-developed-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
In preparation to support SEV-SNP AP Creation, use a variable that holds
the VMSA physical address rather than converting the virtual address.
This will allow SEV-SNP AP Creation to set the new physical address that
will be used should the vCPU reset path be taken.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
Signed-off-by: Michael Roth <michael.roth@amd.com>
Add support for the SEV-SNP AP Creation NAE event. This allows SEV-SNP
guests to alter the register state of the APs on their own. This allows
the guest a way of simulating INIT-SIPI.

A new event, KVM_REQ_UPDATE_PROTECTED_GUEST_STATE, is created and used
so as to avoid updating the VMSA pointer while the vCPU is running.

For CREATE
  The guest supplies the GPA of the VMSA to be used for the vCPU with
  the specified APIC ID. The GPA is saved in the svm struct of the
  target vCPU, the KVM_REQ_UPDATE_PROTECTED_GUEST_STATE event is added
  to the vCPU and then the vCPU is kicked.

For CREATE_ON_INIT:
  The guest supplies the GPA of the VMSA to be used for the vCPU with
  the specified APIC ID the next time an INIT is performed. The GPA is
  saved in the svm struct of the target vCPU.

For DESTROY:
  The guest indicates it wishes to stop the vCPU. The GPA is cleared
  from the svm struct, the KVM_REQ_UPDATE_PROTECTED_GUEST_STATE event is
  added to vCPU and then the vCPU is kicked.

The KVM_REQ_UPDATE_PROTECTED_GUEST_STATE event handler will be invoked
as a result of the event or as a result of an INIT. The handler sets the
vCPU to the KVM_MP_STATE_UNINITIALIZED state, so that any errors will
leave the vCPU as not runnable. Any previous VMSA pages that were
installed as part of an SEV-SNP AP Creation NAE event are un-pinned. If
a new VMSA is to be installed, the VMSA guest page is pinned and set as
the VMSA in the vCPU VMCB and the vCPU state is set to
KVM_MP_STATE_RUNNABLE. If a new VMSA is not to be installed, the VMSA is
cleared in the vCPU VMCB and the vCPU state is left as
KVM_MP_STATE_UNINITIALIZED to prevent it from being run.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
[mdr: add handling for gmem]
Signed-off-by: Michael Roth <michael.roth@amd.com>
GHCB version 2 adds support for a GHCB-based termination request that
a guest can issue when it reaches an error state and wishes to inform
the hypervisor that it should be terminated. Implement support for that
similarly to GHCB MSR-based termination requests that are already
available to SEV-ES guests via earlier versions of the GHCB protocol.

See 'Termination Request' in the 'Invoking VMGEXIT' section of the GHCB
specification for more details.

Signed-off-by: Michael Roth <michael.roth@amd.com>
This will handle RMP table updates and direct map changes needed to put
a page into a private state before mapping it into an SEV-SNP guest.

Signed-off-by: Michael Roth <michael.roth@amd.com>
Implement a platform hook to do the work of restoring the direct map
entries of gmem-managed pages and transitioning the corresponding RMP
table entries back to the default shared/hypervisor-owned state.

Signed-off-by: Michael Roth <michael.roth@amd.com>
In the case of SEV-SNP, whether or not a 2MB page can be mapped via a
2MB mapping in the guest's nested page table depends on whether or not
any subpages within the range have already been initialized as private
in the RMP table. The existing mixed-attribute tracking in KVM is
insufficient here, for instance:

  - gmem allocates 2MB page
  - guest issues PVALIDATE on 2MB page
  - guest later converts a subpage to shared
  - SNP host code issues PSMASH to split 2MB RMP mapping to 4K
  - KVM MMU splits NPT mapping to 4K

At this point there are no mixed attributes, and KVM would normally
allow for 2MB NPT mappings again, but this is actually not allowed
because the RMP table mappings are 4K and cannot be promoted on the
hypervisor side, so the NPT mappings must still be limited to 4K to
match this.

Add a hook to determine the max NPT mapping size in situations like
this.

Signed-off-by: Michael Roth <michael.roth@amd.com>
With SNP/guest_memfd, private/encrypted memory should not be mappable,
and MMU notifications for HVA-mapped memory will only be relevant to
unencrypted guest memory. Therefore, the rationale behind issuing a
wbinvd_on_all_cpus() in sev_guest_memory_reclaimed() should not apply
for SNP guests and can be ignored.

Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
[mdr: Add some clarifications in commit]
Signed-off-by: Michael Roth <michael.roth@amd.com>
Add a module parameter than can be used to enable or disable the SEV-SNP
feature. Now that KVM contains the support for the SNP set the GHCB
hypervisor feature flag to indicate that SNP is supported.

Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
Version 2 of GHCB specification added support for the SNP Guest Request
Message NAE event. The event allows for an SEV-SNP guest to make
requests to the SEV-SNP firmware through hypervisor using the
SNP_GUEST_REQUEST API defined in the SEV-SNP firmware specification.

This is used by guests primarily to request attestation reports from
firmware. There are other request types are available as well, but the
specifics of what guest requests are being made are opaque to the
hypervisor, which only serves as a proxy for the guest requests and
firmware responses.

Implement handling for these events.

Co-developed-by: Alexey Kardashevskiy <aik@amd.com>
Signed-off-by: Alexey Kardashevskiy <aik@amd.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
[mdr: ensure FW command failures are indicated to guest, drop extended
 request handling to be re-written as separate patch, massage commit]
Signed-off-by: Michael Roth <michael.roth@amd.com>
These commands can be used to create a transaction such that commands
that update the reported TCB, such as SNP_SET_CONFIG/SNP_COMMIT, and
updates to userspace-supplied certificates, can be handled atomically
relative to any extended guest requests issued by any SNP guests while
the updates are taking place.

Without this interface, there is a risk that a guest will be given
certificate information that does not correspond to the VCEK/VLEK used
to sign a particular attestation report unless all the running guests
are paused in advance, which would cause disruption to all guests in the
system even if no attestation requests are being made. Even then, care
is needed to ensure that KVM does not pass along certificate information
that was fetched from userspace in advance of the guest being paused.

This interface also provides some versatility with how similar firmware
maintenance activity can be handled in the future without passing
unnecessary management complexity on to userspace.

Signed-off-by: Michael Roth <michael.roth@amd.com>
Version 2 of GHCB specification added support for the SNP Extended Guest
Request Message NAE event. This event serves a nearly identical purpose
to the previously-added SNP_GUEST_REQUEST event, but allows for
additional certificate data to be supplied via an additional
guest-supplied buffer to be used mainly for verifying the signature of
an attestation report as returned by firmware.

This certificate data is supplied by userspace, so unlike with
SNP_GUEST_REQUEST events, SNP_EXTENDED_GUEST_REQUEST events are first
forwarded to userspace via a KVM_EXIT_VMGEXIT exit type, and then the
firmware request is made only afterward.

Implement handling for these events.

Since there is a potential for race conditions where the
userspace-supplied certificate data may be out-of-sync relative to the
reported TCB that firmware will use when signing attestation reports,
make use of the transaction/synchronization mechanisms added by the
SNP_SET_CONFIG_{START,END} SEV device ioctls such that the guest will be
told to retry the request when an update to reported TCB or
userspace-supplied certificates may have occurred or is in progress
while an extended guest request is being processed.

Signed-off-by: Michael Roth <michael.roth@amd.com>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Labels

None yet

Projects

None yet

Development

Successfully merging this pull request may close these issues.