Add "ARCH" to the symbols; shortly, the "prepare" phase will include both
the arch-independent step to clear out contents left in the page by the
host, and the arch-dependent step enabled by CONFIG_HAVE_KVM_GMEM_PREPARE.
For consistency do the same for CONFIG_HAVE_KVM_GMEM_INVALIDATE as well.
Reviewed-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We have a perfectly usable folio, use it to retrieve the pfn and order.
All that's needed is a version of folio_file_page that returns a pfn.
Reviewed-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The up-to-date flag as is now is not too useful; it tells guest_memfd not
to overwrite the contents of a folio, but it doesn't say that the page
is ready to be mapped into the guest. For encrypted guests, mapping
a private page requires that the "preparation" phase has succeeded,
and at the same time the same page cannot be prepared twice.
So, ensure that folio_mark_uptodate() is only called on a prepared page. If
kvm_gmem_prepare_folio() or the post_populate callback fail, the folio
will not be marked up-to-date; it's not a problem to call clear_highpage()
again on such a page prior to the next preparation attempt.
Reviewed-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Right now this is simply more consistent and avoids use of pfn_to_page()
and put_page(). It will be put to more use in upcoming patches, to
ensure that the up-to-date flag is set at the very end of both the
kvm_gmem_get_pfn() and kvm_gmem_populate() flows.
Reviewed-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM_PRE_FAULT_MEMORY for an SNP guest can race with
sev_gmem_post_populate() in bad ways. The following sequence for
instance can potentially trigger an RMP fault:
thread A, sev_gmem_post_populate: called
thread B, sev_gmem_prepare: places below 'pfn' in a private state in RMP
thread A, sev_gmem_post_populate: *vaddr = kmap_local_pfn(pfn + i);
thread A, sev_gmem_post_populate: copy_from_user(vaddr, src + i * PAGE_SIZE, PAGE_SIZE);
RMP #PF
Fix this by only allowing KVM_PRE_FAULT_MEMORY to run after a guest's
initial private memory contents have been finalized via
KVM_SEV_SNP_LAUNCH_FINISH.
Beyond fixing this issue, it just sort of makes sense to enforce this,
since the KVM_PRE_FAULT_MEMORY documentation states:
"KVM maps memory as if the vCPU generated a stage-2 read page fault"
which sort of implies we should be acting on the same guest state that a
vCPU would see post-launch after the initial guest memory is all set up.
Co-developed-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When requesting an attestation report a guest is able to specify whether
it wants SNP firmware to sign the report using either a Versioned Chip
Endorsement Key (VCEK), which is derived from chip-unique secrets, or a
Versioned Loaded Endorsement Key (VLEK) which is obtained from an AMD
Key Derivation Service (KDS) and derived from seeds allocated to
enrolled cloud service providers (CSPs).
For VLEK keys, an SNP_VLEK_LOAD SNP firmware command is used to load
them into the system after obtaining them from the KDS. Add a
corresponding userspace interface so to allow the loading of VLEK keys
into the system.
See SEV-SNP Firmware ABI 1.54, SNP_VLEK_LOAD for more details.
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Michael Roth <michael.roth@amd.com>
Message-ID: <20240501085210.2213060-21-michael.roth@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Introduces kvm_x86_call(), to streamline the usage of static calls of
kvm_x86_ops. The current implementation of these calls is verbose and
could lead to alignment challenges. This makes the code susceptible to
exceeding the "80 columns per single line of code" limit as defined in
the coding-style document. Another issue with the existing implementation
is that the addition of kvm_x86_ prefix to hooks at the static_call sites
hinders code readability and navigation. kvm_x86_call() is added to
improve code readability and maintainability, while adhering to the coding
style guidelines.
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Link: https://lore.kernel.org/r/20240507133103.15052-3-wei.w.wang@intel.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The GHCB 2.0 specification defines 2 GHCB request types to allow SNP guests
to send encrypted messages/requests to firmware: SNP Guest Requests and SNP
Extended Guest Requests. These encrypted messages are used for things like
servicing attestation requests issued by the guest. Implementing support for
these is required to be fully GHCB-compliant.
For the most part, KVM only needs to handle forwarding these requests to
firmware (to be issued via the SNP_GUEST_REQUEST firmware command defined
in the SEV-SNP Firmware ABI), and then forwarding the encrypted response to
the guest.
However, in the case of SNP Extended Guest Requests, the host is also
able to provide the certificate data corresponding to the endorsement key
used by firmware to sign attestation report requests. This certificate data
is provided by userspace because:
1) It allows for different keys/key types to be used for each particular
guest with requiring any sort of KVM API to configure the certificate
table in advance on a per-guest basis.
2) It provides additional flexibility with how attestation requests might
be handled during live migration where the certificate data for
source/dest might be different.
3) It allows all synchronization between certificates and firmware/signing
key updates to be handled purely by userspace rather than requiring
some in-kernel mechanism to facilitate it. [1]
To support fetching certificate data from userspace, a new KVM exit type will
be needed to handle fetching the certificate from userspace. An attempt to
define a new KVM_EXIT_COCO/KVM_EXIT_COCO_REQ_CERTS exit type to handle this
was introduced in v1 of this patchset, but is still being discussed by
community, so for now this patchset only implements a stub version of SNP
Extended Guest Requests that does not provide certificate data, but is still
enough to provide compliance with the GHCB 2.0 spec.
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 for certain message
types it allows the guest to supply a buffer to be used for additional
information in some cases.
Currently the GHCB spec only defines extended handling of this sort in
the case of attestation requests, where the additional buffer is used to
supply a table of certificate data corresponding to the attestion
report's signing key. Support for this extended handling will require
additional KVM APIs to handle coordinating with userspace.
Whether or not the hypervisor opts to provide this certificate data is
optional. However, support for processing SNP_EXTENDED_GUEST_REQUEST
GHCB requests is required by the GHCB 2.0 specification for SNP guests,
so for now implement a stub implementation that provides an empty
certificate table to the guest if it supplies an additional buffer, but
otherwise behaves identically to SNP_GUEST_REQUEST.
Reviewed-by: Carlos Bilbao <carlos.bilbao.osdev@gmail.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Signed-off-by: Michael Roth <michael.roth@amd.com>
Message-ID: <20240701223148.3798365-4-michael.roth@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
sev_guest.h currently contains various definitions relating to the
format of SNP_GUEST_REQUEST commands to SNP firmware. Currently only the
sev-guest driver makes use of them, but when the KVM side of this is
implemented there's a need to parse the SNP_GUEST_REQUEST header to
determine whether additional information needs to be provided to the
guest. Prepare for this by moving those definitions to a common header
that's shared by host/guest code so that KVM can also make use of them.
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Signed-off-by: Michael Roth <michael.roth@amd.com>
Message-ID: <20240701223148.3798365-3-michael.roth@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.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 the 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 generally does not
affect how they are handled by the hypervisor, which only serves as a
proxy for the guest requests and firmware responses.
Implement handling for these events.
When an SNP Guest Request is issued, the guest will provide its own
request/response pages, which could in theory be passed along directly
to firmware. However, these pages would need special care:
- Both pages are from shared guest memory, so they need to be
protected from migration/etc. occurring while firmware reads/writes
to them. At a minimum, this requires elevating the ref counts and
potentially needing an explicit pinning of the memory. This places
additional restrictions on what type of memory backends userspace
can use for shared guest memory since there would be some reliance
on using refcounted pages.
- The response page needs to be switched to Firmware-owned state
before the firmware can write to it, which can lead to potential
host RMP #PFs if the guest is misbehaved and hands the host a
guest page that KVM is writing to for other reasons (e.g. virtio
buffers).
Both of these issues can be avoided completely by using
separately-allocated bounce pages for both the request/response pages
and passing those to firmware instead. So that's the approach taken
here.
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Co-developed-by: Alexey Kardashevskiy <aik@amd.com>
Signed-off-by: Alexey Kardashevskiy <aik@amd.com>
Co-developed-by: Ashish Kalra <ashish.kalra@amd.com>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.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>
Message-ID: <20240701223148.3798365-2-michael.roth@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Explicitly suppress userspace emulated MMIO exits that are triggered when
emulating a task switch as KVM doesn't support userspace MMIO during
complex (multi-step) emulation. Silently ignoring the exit request can
result in the WARN_ON_ONCE(vcpu->mmio_needed) firing if KVM exits to
userspace for some other reason prior to purging mmio_needed.
See commit 0dc902267c ("KVM: x86: Suppress pending MMIO write exits if
emulator detects exception") for more details on KVM's limitations with
respect to emulated MMIO during complex emulator flows.
Reported-by: syzbot+2fb9f8ed752c01bc9a3f@syzkaller.appspotmail.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20240712144841.1230591-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Tweak the definition of make_huge_page_split_spte() to eliminate an
unnecessarily long line, and opportunistically initialize child_spte to
make it more obvious that the child is directly derived from the huge
parent.
No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20240712151335.1242633-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Bug the VM instead of simply warning if KVM tries to split a SPTE that is
non-present or not-huge. KVM is guaranteed to end up in a broken state as
the callers fully expect a valid SPTE, e.g. the shadow MMU will add an
rmap entry, and all MMUs will account the expected small page. Returning
'0' is also technically wrong now that SHADOW_NONPRESENT_VALUE exists,
i.e. would cause KVM to create a potential #VE SPTE.
While it would be possible to have the callers gracefully handle failure,
doing so would provide no practical value as the scenario really should be
impossible, while the error handling would add a non-trivial amount of
noise.
Fixes: a3fe5dbda0 ("KVM: x86/mmu: Split huge pages mapped by the TDP MMU when dirty logging is enabled")
Cc: David Matlack <dmatlack@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20240712151335.1242633-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM VMX changes for 6.11
- Remove an unnecessary EPT TLB flush when enabling hardware.
- Fix a series of bugs that cause KVM to fail to detect nested pending posted
interrupts as valid wake eents for a vCPU executing HLT in L2 (with
HLT-exiting disable by L1).
- Misc cleanups
KVM SVM changes for 6.11
- Make per-CPU save_area allocations NUMA-aware.
- Force sev_es_host_save_area() to be inlined to avoid calling into an
instrumentable function from noinstr code.
KVM selftests for 6.11
- Remove dead code in the memslot modification stress test.
- Treat "branch instructions retired" as supported on all AMD Family 17h+ CPUs.
- Print the guest pseudo-RNG seed only when it changes, to avoid spamming the
log for tests that create lots of VMs.
- Make the PMU counters test less flaky when counting LLC cache misses by
doing CLFLUSH{OPT} in every loop iteration.
KVM x86/pmu changes for 6.11
- Don't advertise IA32_PERF_GLOBAL_OVF_CTRL as an MSR-to-be-saved, as it reads
'0' and writes from userspace are ignored.
- Update to the newfangled Intel CPU FMS infrastructure.
- Use macros instead of open-coded literals to clean up KVM's manipulation of
FIXED_CTR_CTRL MSRs.
KVM x86 MTRR virtualization removal
Remove support for virtualizing MTRRs on Intel CPUs, along with a nasty CR0.CD
hack, and instead always honor guest PAT on CPUs that support self-snoop.
KVM x86 MMU changes for 6.11
- Don't allocate kvm_mmu_page.shadowed_translation for shadow pages that can't
hold leafs SPTEs.
- Unconditionally drop mmu_lock when allocating TDP MMU page tables for eager
page splitting to avoid stalling vCPUs when splitting huge pages.
- Misc cleanups
KVM x86 misc changes for 6.11
- Add a global struct to consolidate tracking of host values, e.g. EFER, and
move "shadow_phys_bits" into the structure as "maxphyaddr".
- Add KVM_CAP_X86_APIC_BUS_CYCLES_NS to allow configuring the effective APIC
bus frequency, because TDX.
- Print the name of the APICv/AVIC inhibits in the relevant tracepoint.
- Clean up KVM's handling of vendor specific emulation to consistently act on
"compatible with Intel/AMD", versus checking for a specific vendor.
- Misc cleanups
KVM generic changes for 6.11
- Enable halt poll shrinking by default, as Intel found it to be a clear win.
- Setup empty IRQ routing when creating a VM to avoid having to synchronize
SRCU when creating a split IRQCHIP on x86.
- Rework the sched_in/out() paths to replace kvm_arch_sched_in() with a flag
that arch code can use for hooking both sched_in() and sched_out().
- Take the vCPU @id as an "unsigned long" instead of "u32" to avoid
truncating a bogus value from userspace, e.g. to help userspace detect bugs.
- Mark a vCPU as preempted if and only if it's scheduled out while in the
KVM_RUN loop, e.g. to avoid marking it preempted and thus writing guest
memory when retrieving guest state during live migration blackout.
- A few minor cleanups
KVM Xen:
Fix a bug where KVM fails to check the validity of an incoming userspace
virtual address and tries to activate a gfn_to_pfn_cache with a kernel address.
KVM/arm64 changes for 6.11
- Initial infrastructure for shadow stage-2 MMUs, as part of nested
virtualization enablement
- Support for userspace changes to the guest CTR_EL0 value, enabling
(in part) migration of VMs between heterogenous hardware
- Fixes + improvements to pKVM's FF-A proxy, adding support for v1.1 of
the protocol
- FPSIMD/SVE support for nested, including merged trap configuration
and exception routing
- New command-line parameter to control the WFx trap behavior under KVM
- Introduce kCFI hardening in the EL2 hypervisor
- Fixes + cleanups for handling presence/absence of FEAT_TCRX
- Miscellaneous fixes + documentation updates
* kvm-arm64/docs:
: KVM Documentation fixes, courtesy of Changyuan Lyu
:
: Small set of typo fixes / corrections to the KVM API documentation
: relating to MSIs and arm64 VGIC UAPI.
MAINTAINERS: Include documentation in KVM/arm64 entry
KVM: Documentation: Correct the VGIC V2 CPU interface addr space size
KVM: Documentation: Enumerate allowed value macros of `irq_type`
KVM: Documentation: Fix typo `BFD`
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
* kvm-arm64/nv-tcr2:
: Fixes to the handling of TCR_EL1, courtesy of Marc Zyngier
:
: Series addresses a couple gaps that are present in KVM (from cover
: letter):
:
: - VM configuration: HCRX_EL2.TCR2En is forced to 1, and we blindly
: save/restore stuff.
:
: - trap bit description and routing: none, obviously, since we make a
: point in not trapping.
KVM: arm64: Honor trap routing for TCR2_EL1
KVM: arm64: Make PIR{,E0}_EL1 save/restore conditional on FEAT_TCRX
KVM: arm64: Make TCR2_EL1 save/restore dependent on the VM features
KVM: arm64: Get rid of HCRX_GUEST_FLAGS
KVM: arm64: Correctly honor the presence of FEAT_TCRX
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
* kvm-arm64/nv-sve:
: CPTR_EL2, FPSIMD/SVE support for nested
:
: This series brings support for honoring the guest hypervisor's CPTR_EL2
: trap configuration when running a nested guest, along with support for
: FPSIMD/SVE usage at L1 and L2.
KVM: arm64: Allow the use of SVE+NV
KVM: arm64: nv: Add additional trap setup for CPTR_EL2
KVM: arm64: nv: Add trap description for CPTR_EL2
KVM: arm64: nv: Add TCPAC/TTA to CPTR->CPACR conversion helper
KVM: arm64: nv: Honor guest hypervisor's FP/SVE traps in CPTR_EL2
KVM: arm64: nv: Load guest FP state for ZCR_EL2 trap
KVM: arm64: nv: Handle CPACR_EL1 traps
KVM: arm64: Spin off helper for programming CPTR traps
KVM: arm64: nv: Ensure correct VL is loaded before saving SVE state
KVM: arm64: nv: Use guest hypervisor's max VL when running nested guest
KVM: arm64: nv: Save guest's ZCR_EL2 when in hyp context
KVM: arm64: nv: Load guest hyp's ZCR into EL1 state
KVM: arm64: nv: Handle ZCR_EL2 traps
KVM: arm64: nv: Forward SVE traps to guest hypervisor
KVM: arm64: nv: Forward FP/ASIMD traps to guest hypervisor
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
* kvm-arm64/el2-kcfi:
: kCFI support in the EL2 hypervisor, courtesy of Pierre-Clément Tosi
:
: Enable the usage fo CONFIG_CFI_CLANG (kCFI) for hardening indirect
: branches in the EL2 hypervisor. Unlike kernel support for the feature,
: CFI failures at EL2 are always fatal.
KVM: arm64: nVHE: Support CONFIG_CFI_CLANG at EL2
KVM: arm64: Introduce print_nvhe_hyp_panic helper
arm64: Introduce esr_brk_comment, esr_is_cfi_brk
KVM: arm64: VHE: Mark __hyp_call_panic __noreturn
KVM: arm64: nVHE: gen-hyprel: Skip R_AARCH64_ABS32
KVM: arm64: nVHE: Simplify invalid_host_el2_vect
KVM: arm64: Fix __pkvm_init_switch_pgd call ABI
KVM: arm64: Fix clobbered ELR in sync abort/SError
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
* kvm-arm64/ctr-el0:
: Support for user changes to CTR_EL0, courtesy of Sebastian Ott
:
: Allow userspace to change the guest-visible value of CTR_EL0 for a VM,
: so long as the requested value represents a subset of features supported
: by hardware. In other words, prevent the VMM from over-promising the
: capabilities of hardware.
:
: Make this happen by fitting CTR_EL0 into the existing infrastructure for
: feature ID registers.
KVM: selftests: Assert that MPIDR_EL1 is unchanged across vCPU reset
KVM: arm64: nv: Unfudge ID_AA64PFR0_EL1 masking
KVM: selftests: arm64: Test writes to CTR_EL0
KVM: arm64: rename functions for invariant sys regs
KVM: arm64: show writable masks for feature registers
KVM: arm64: Treat CTR_EL0 as a VM feature ID register
KVM: arm64: unify code to prepare traps
KVM: arm64: nv: Use accessors for modifying ID registers
KVM: arm64: Add helper for writing ID regs
KVM: arm64: Use read-only helper for reading VM ID registers
KVM: arm64: Make idregs debugfs iterator search sysreg table directly
KVM: arm64: Get sys_reg encoding from descriptor in idregs_debug_show()
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
* kvm-arm64/shadow-mmu:
: Shadow stage-2 MMU support for NV, courtesy of Marc Zyngier
:
: Initial implementation of shadow stage-2 page tables to support a guest
: hypervisor. In the author's words:
:
: So here's the 10000m (approximately 30000ft for those of you stuck
: with the wrong units) view of what this is doing:
:
: - for each {VMID,VTTBR,VTCR} tuple the guest uses, we use a
: separate shadow s2_mmu context. This context has its own "real"
: VMID and a set of page tables that are the combination of the
: guest's S2 and the host S2, built dynamically one fault at a time.
:
: - these shadow S2 contexts are ephemeral, and behave exactly as
: TLBs. For all intent and purposes, they *are* TLBs, and we discard
: them pretty often.
:
: - TLB invalidation takes three possible paths:
:
: * either this is an EL2 S1 invalidation, and we directly emulate
: it as early as possible
:
: * or this is an EL1 S1 invalidation, and we need to apply it to
: the shadow S2s (plural!) that match the VMID set by the L1 guest
:
: * or finally, this is affecting S2, and we need to teardown the
: corresponding part of the shadow S2s, which invalidates the TLBs
KVM: arm64: nv: Truely enable nXS TLBI operations
KVM: arm64: nv: Add handling of NXS-flavoured TLBI operations
KVM: arm64: nv: Add handling of range-based TLBI operations
KVM: arm64: nv: Add handling of outer-shareable TLBI operations
KVM: arm64: nv: Invalidate TLBs based on shadow S2 TTL-like information
KVM: arm64: nv: Tag shadow S2 entries with guest's leaf S2 level
KVM: arm64: nv: Handle FEAT_TTL hinted TLB operations
KVM: arm64: nv: Handle TLBI IPAS2E1{,IS} operations
KVM: arm64: nv: Handle TLBI ALLE1{,IS} operations
KVM: arm64: nv: Handle TLBI VMALLS12E1{,IS} operations
KVM: arm64: nv: Handle TLB invalidation targeting L2 stage-1
KVM: arm64: nv: Handle EL2 Stage-1 TLB invalidation
KVM: arm64: nv: Add Stage-1 EL2 invalidation primitives
KVM: arm64: nv: Unmap/flush shadow stage 2 page tables
KVM: arm64: nv: Handle shadow stage 2 page faults
KVM: arm64: nv: Implement nested Stage-2 page table walk logic
KVM: arm64: nv: Support multiple nested Stage-2 mmu structures
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
* kvm-arm64/ffa-1p1:
: Improvements to the pKVM FF-A Proxy, courtesy of Sebastian Ene
:
: Various minor improvements to how host FF-A calls are proxied with the
: TEE, along with support for v1.1 of the protocol.
KVM: arm64: Use FF-A 1.1 with pKVM
KVM: arm64: Update the identification range for the FF-A smcs
KVM: arm64: Add support for FFA_PARTITION_INFO_GET
KVM: arm64: Trap FFA_VERSION host call in pKVM
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
* kvm-arm64/misc:
: Miscellaneous updates
:
: - Provide a command-line parameter to statically control the WFx trap
: selection in KVM
:
: - Make sysreg masks allocation accounted
Revert "KVM: arm64: nv: Fix RESx behaviour of disabled FGTs with negative polarity"
KVM: arm64: nv: Use GFP_KERNEL_ACCOUNT for sysreg_masks allocation
KVM: arm64: nv: Fix RESx behaviour of disabled FGTs with negative polarity
KVM: arm64: Add early_param to control WFx trapping
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Assortment of tiny fixes which are not time critical:
- Rejecting memory region operations for ucontrol mode VMs
- Rewind the PSW on host intercepts for VSIE
- Remove unneeded include
KVM/riscv changes for 6.11
- Redirect AMO load/store access fault traps to guest
- Perf kvm stat support for RISC-V
- Use guest files for IMSIC virtualization, when available
ONE_REG support for the Zimop, Zcmop, Zca, Zcf, Zcd, Zcb and Zawrs ISA
extensions is coming through the RISC-V tree.
Pre-population has been requested several times to mitigate KVM page faults
during guest boot or after live migration. It is also required by TDX
before filling in the initial guest memory with measured contents.
Introduce it as a generic API.
Wire KVM_PRE_FAULT_MEMORY ioctl to kvm_mmu_do_page_fault() to populate guest
memory. It can be called right after KVM_CREATE_VCPU creates a vCPU,
since at that point kvm_mmu_create() and kvm_init_mmu() are called and
the vCPU is ready to invoke the KVM page fault handler.
The helper function kvm_tdp_map_page() takes care of the logic to
process RET_PF_* return values and convert them to success or errno.
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Message-ID: <9b866a0ae7147f96571c439e75429a03dcb659b6.1712785629.git.isaku.yamahata@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move the accounting of the result of kvm_mmu_do_page_fault() to its
callers, as only pf_fixed is common to guest page faults and async #PFs,
and upcoming support KVM_PRE_FAULT_MEMORY won't bump _any_ stats.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Account stat.pf_taken in kvm_mmu_page_fault(), i.e. the actual page fault
handler, instead of conditionally bumping it in kvm_mmu_do_page_fault().
The "real" page fault handler is the only path that should ever increment
the number of taken page faults, as all other paths that "do page fault"
are by definition not handling faults that occurred in the guest.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Adds documentation of KVM_PRE_FAULT_MEMORY ioctl. [1]
It populates guest memory. It doesn't do extra operations on the
underlying technology-specific initialization [2]. For example,
CoCo-related operations won't be performed. Concretely for TDX, this API
won't invoke TDH.MEM.PAGE.ADD() or TDH.MR.EXTEND(). Vendor-specific APIs
are required for such operations.
The key point is to adapt of vcpu ioctl instead of VM ioctl. First,
populating guest memory requires vcpu. If it is VM ioctl, we need to pick
one vcpu somehow. Secondly, vcpu ioctl allows each vcpu to invoke this
ioctl in parallel. It helps to scale regarding guest memory size, e.g.,
hundreds of GB.
[1] https://lore.kernel.org/kvm/Zbrj5WKVgMsUFDtb@google.com/
[2] https://lore.kernel.org/kvm/Ze-TJh0BBOWm9spT@google.com/
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Message-ID: <9a060293c9ad9a78f1d8994cfe1311e818e99257.1712785629.git.isaku.yamahata@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The flags AS_UNMOVABLE and AS_INACCESSIBLE were both added just for guest_memfd;
AS_UNMOVABLE is already in existing versions of Linux, while AS_INACCESSIBLE was
acked for inclusion in 6.11.
But really, they are the same thing: only guest_memfd uses them, at least for
now, and guest_memfd pages are unmovable because they should not be
accessed by the CPU.
So merge them into one; use the AS_INACCESSIBLE name which is more comprehensive.
At the same time, this fixes an embarrassing bug where AS_INACCESSIBLE was used
as a bit mask, despite it being just a bit index.
The bug was mostly benign, because AS_INACCESSIBLE's bit representation (1010)
corresponded to setting AS_UNEVICTABLE (which is already set) and AS_ENOSPC
(except no async writes can happen on the guest_memfd). So the AS_INACCESSIBLE
flag simply had no effect.
Fixes: 1d23040caa ("KVM: guest_memfd: Use AS_INACCESSIBLE when creating guest_memfd inode")
Fixes: c72ceafbd1 ("mm: Introduce AS_INACCESSIBLE for encrypted/confidential memory")
Cc: linux-mm@kvack.org
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: David Hildenbrand <david@redhat.com>
Tested-by: Michael Roth <michael.roth@amd.com>
Reviewed-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
