Commit Graph

123 Commits

Author SHA1 Message Date
Linus Torvalds
bf9095424d Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm updates from Paolo Bonzini:
 "S390:

   - ultravisor communication device driver

   - fix TEID on terminating storage key ops

  RISC-V:

   - Added Sv57x4 support for G-stage page table

   - Added range based local HFENCE functions

   - Added remote HFENCE functions based on VCPU requests

   - Added ISA extension registers in ONE_REG interface

   - Updated KVM RISC-V maintainers entry to cover selftests support

  ARM:

   - Add support for the ARMv8.6 WFxT extension

   - Guard pages for the EL2 stacks

   - Trap and emulate AArch32 ID registers to hide unsupported features

   - Ability to select and save/restore the set of hypercalls exposed to
     the guest

   - Support for PSCI-initiated suspend in collaboration with userspace

   - GICv3 register-based LPI invalidation support

   - Move host PMU event merging into the vcpu data structure

   - GICv3 ITS save/restore fixes

   - The usual set of small-scale cleanups and fixes

  x86:

   - New ioctls to get/set TSC frequency for a whole VM

   - Allow userspace to opt out of hypercall patching

   - Only do MSR filtering for MSRs accessed by rdmsr/wrmsr

  AMD SEV improvements:

   - Add KVM_EXIT_SHUTDOWN metadata for SEV-ES

   - V_TSC_AUX support

  Nested virtualization improvements for AMD:

   - Support for "nested nested" optimizations (nested vVMLOAD/VMSAVE,
     nested vGIF)

   - Allow AVIC to co-exist with a nested guest running

   - Fixes for LBR virtualizations when a nested guest is running, and
     nested LBR virtualization support

   - PAUSE filtering for nested hypervisors

  Guest support:

   - Decoupling of vcpu_is_preempted from PV spinlocks"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (199 commits)
  KVM: x86: Fix the intel_pt PMI handling wrongly considered from guest
  KVM: selftests: x86: Sync the new name of the test case to .gitignore
  Documentation: kvm: reorder ARM-specific section about KVM_SYSTEM_EVENT_SUSPEND
  x86, kvm: use correct GFP flags for preemption disabled
  KVM: LAPIC: Drop pending LAPIC timer injection when canceling the timer
  x86/kvm: Alloc dummy async #PF token outside of raw spinlock
  KVM: x86: avoid calling x86 emulator without a decoded instruction
  KVM: SVM: Use kzalloc for sev ioctl interfaces to prevent kernel data leak
  x86/fpu: KVM: Set the base guest FPU uABI size to sizeof(struct kvm_xsave)
  s390/uv_uapi: depend on CONFIG_S390
  KVM: selftests: x86: Fix test failure on arch lbr capable platforms
  KVM: LAPIC: Trace LAPIC timer expiration on every vmentry
  KVM: s390: selftest: Test suppression indication on key prot exception
  KVM: s390: Don't indicate suppression on dirtying, failing memop
  selftests: drivers/s390x: Add uvdevice tests
  drivers/s390/char: Add Ultravisor io device
  MAINTAINERS: Update KVM RISC-V entry to cover selftests support
  RISC-V: KVM: Introduce ISA extension register
  RISC-V: KVM: Cleanup stale TLB entries when host CPU changes
  RISC-V: KVM: Add remote HFENCE functions based on VCPU requests
  ...
2022-05-26 14:20:14 -07:00
Catalin Marinas
0616ea3f1b Merge branch 'for-next/esr-elx-64-bit' into for-next/core
* for-next/esr-elx-64-bit:
  : Treat ESR_ELx as a 64-bit register.
  KVM: arm64: uapi: Add kvm_debug_exit_arch.hsr_high
  KVM: arm64: Treat ESR_EL2 as a 64-bit register
  arm64: Treat ESR_ELx as a 64-bit register
  arm64: compat: Do not treat syscall number as ESR_ELx for a bad syscall
  arm64: Make ESR_ELx_xVC_IMM_MASK compatible with assembly
2022-05-20 18:51:54 +01:00
Mark Brown
0eda2ec489 arm64/sysreg: Standardise ID_AA64ISAR0_EL1 macro names
The macros for accessing fields in ID_AA64ISAR0_EL1 omit the _EL1 from the
name of the register. In preparation for converting this register to be
automatically generated update the names to include an _EL1, there should
be no functional change.

Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20220503170233.507788-8-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-05-04 15:30:28 +01:00
Mark Brown
6329eb543d arm64: Update name of ID_AA64ISAR0_EL1_ATOMIC to reflect ARM
The architecture reference manual refers to the field in bits 23:20 of
ID_AA64ISAR0_EL1 with the name "atomic" but the kernel defines for this
bitfield use the name "atomics". Bring the two into sync to make it easier
to cross reference with the specification.

Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20220503170233.507788-7-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-05-04 15:30:28 +01:00
Alexandru Elisei
0b12620fdd KVM: arm64: Treat ESR_EL2 as a 64-bit register
ESR_EL2 was defined as a 32-bit register in the initial release of the
ARM Architecture Manual for Armv8-A, and was later extended to 64 bits,
with bits [63:32] RES0. ARMv8.7 introduced FEAT_LS64, which makes use of
bits [36:32].

KVM treats ESR_EL1 as a 64-bit register when saving and restoring the
guest context, but ESR_EL2 is handled as a 32-bit register. Start
treating ESR_EL2 as a 64-bit register to allow KVM to make use of the
most significant 32 bits in the future.

The type chosen to represent ESR_EL2 is u64, as that is consistent with the
notation KVM overwhelmingly uses today (u32), and how the rest of the
registers are declared.

Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220425114444.368693-5-alexandru.elisei@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-04-29 19:26:27 +01:00
Kalesh Singh
f922c13e77 KVM: arm64: Introduce pkvm_alloc_private_va_range()
pkvm_hyp_alloc_private_va_range() can be used to reserve private VA ranges
in the pKVM nVHE hypervisor. Allocations are aligned based on the order of
the requested size.

This will be used to implement stack guard pages for pKVM nVHE hypervisor
(in a subsequent patch in the series).

Credits to Quentin Perret <qperret@google.com> for the idea of moving
private VA allocation out of __pkvm_create_private_mapping()

Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220420214317.3303360-3-kaleshsingh@google.com
2022-04-28 20:53:13 +01:00
Linus Torvalds
1ebdbeb03e Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm updates from Paolo Bonzini:
 "ARM:
   - Proper emulation of the OSLock feature of the debug architecture

   - Scalibility improvements for the MMU lock when dirty logging is on

   - New VMID allocator, which will eventually help with SVA in VMs

   - Better support for PMUs in heterogenous systems

   - PSCI 1.1 support, enabling support for SYSTEM_RESET2

   - Implement CONFIG_DEBUG_LIST at EL2

   - Make CONFIG_ARM64_ERRATUM_2077057 default y

   - Reduce the overhead of VM exit when no interrupt is pending

   - Remove traces of 32bit ARM host support from the documentation

   - Updated vgic selftests

   - Various cleanups, doc updates and spelling fixes

  RISC-V:
   - Prevent KVM_COMPAT from being selected

   - Optimize __kvm_riscv_switch_to() implementation

   - RISC-V SBI v0.3 support

  s390:
   - memop selftest

   - fix SCK locking

   - adapter interruptions virtualization for secure guests

   - add Claudio Imbrenda as maintainer

   - first step to do proper storage key checking

  x86:
   - Continue switching kvm_x86_ops to static_call(); introduce
     static_call_cond() and __static_call_ret0 when applicable.

   - Cleanup unused arguments in several functions

   - Synthesize AMD 0x80000021 leaf

   - Fixes and optimization for Hyper-V sparse-bank hypercalls

   - Implement Hyper-V's enlightened MSR bitmap for nested SVM

   - Remove MMU auditing

   - Eager splitting of page tables (new aka "TDP" MMU only) when dirty
     page tracking is enabled

   - Cleanup the implementation of the guest PGD cache

   - Preparation for the implementation of Intel IPI virtualization

   - Fix some segment descriptor checks in the emulator

   - Allow AMD AVIC support on systems with physical APIC ID above 255

   - Better API to disable virtualization quirks

   - Fixes and optimizations for the zapping of page tables:

      - Zap roots in two passes, avoiding RCU read-side critical
        sections that last too long for very large guests backed by 4
        KiB SPTEs.

      - Zap invalid and defunct roots asynchronously via
        concurrency-managed work queue.

      - Allowing yielding when zapping TDP MMU roots in response to the
        root's last reference being put.

      - Batch more TLB flushes with an RCU trick. Whoever frees the
        paging structure now holds RCU as a proxy for all vCPUs running
        in the guest, i.e. to prolongs the grace period on their behalf.
        It then kicks the the vCPUs out of guest mode before doing
        rcu_read_unlock().

  Generic:
   - Introduce __vcalloc and use it for very large allocations that need
     memcg accounting"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (246 commits)
  KVM: use kvcalloc for array allocations
  KVM: x86: Introduce KVM_CAP_DISABLE_QUIRKS2
  kvm: x86: Require const tsc for RT
  KVM: x86: synthesize CPUID leaf 0x80000021h if useful
  KVM: x86: add support for CPUID leaf 0x80000021
  KVM: x86: do not use KVM_X86_OP_OPTIONAL_RET0 for get_mt_mask
  Revert "KVM: x86/mmu: Zap only TDP MMU leafs in kvm_zap_gfn_range()"
  kvm: x86/mmu: Flush TLB before zap_gfn_range releases RCU
  KVM: arm64: fix typos in comments
  KVM: arm64: Generalise VM features into a set of flags
  KVM: s390: selftests: Add error memop tests
  KVM: s390: selftests: Add more copy memop tests
  KVM: s390: selftests: Add named stages for memop test
  KVM: s390: selftests: Add macro as abstraction for MEM_OP
  KVM: s390: selftests: Split memop tests
  KVM: s390x: fix SCK locking
  RISC-V: KVM: Implement SBI HSM suspend call
  RISC-V: KVM: Add common kvm_riscv_vcpu_wfi() function
  RISC-V: Add SBI HSM suspend related defines
  RISC-V: KVM: Implement SBI v0.3 SRST extension
  ...
2022-03-24 11:58:57 -07:00
Will Deacon
8d93b7a242 Merge branch 'for-next/fpsimd' into for-next/core
* for-next/fpsimd:
  arm64: cpufeature: Warn if we attempt to read a zero width field
  arm64: cpufeature: Add missing .field_width for GIC system registers
  arm64: signal: nofpsimd: Do not allocate fp/simd context when not available
  arm64: cpufeature: Always specify and use a field width for capabilities
  arm64: Always use individual bits in CPACR floating point enables
  arm64: Define CPACR_EL1_FPEN similarly to other floating point controls
2022-03-14 19:04:22 +00:00
Mark Brown
3bb72d86d8 arm64: Always use individual bits in CPACR floating point enables
CPACR_EL1 has several bitfields for controlling traps for floating point
features to EL1, each of which has a separate bits for EL0 and EL1. Marc
Zyngier noted that we are not consistent in our use of defines to
manipulate these, sometimes using a define covering the whole field and
sometimes using defines for the individual bits. Make this consistent by
expanding the whole field defines where they are used (currently only in
the KVM code) and deleting them so that no further uses can be
introduced.

Suggested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220207152109.197566-3-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2022-02-25 14:28:18 +00:00
Vladimir Murzin
def8c222f0 arm64: Add support of PAuth QARMA3 architected algorithm
QARMA3 is relaxed version of the QARMA5 algorithm which expected to
reduce the latency of calculation while still delivering a suitable
level of security.

Support for QARMA3 can be discovered via ID_AA64ISAR2_EL1

    APA3, bits [15:12] Indicates whether the QARMA3 algorithm is
                       implemented in the PE for address
                       authentication in AArch64 state.

    GPA3, bits [11:8]  Indicates whether the QARMA3 algorithm is
                       implemented in the PE for generic code
                       authentication in AArch64 state.

Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220224124952.119612-4-vladimir.murzin@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2022-02-25 13:38:52 +00:00
Mark Brown
01a244decc KVM: arm64: Add some more comments in kvm_hyp_handle_fpsimd()
The handling for FPSIMD/SVE traps is multi stage and involves some trap
manipulation which isn't quite so immediately obvious as might be desired
so add a few more comments.

Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220124155720.3943374-3-broonie@kernel.org
2022-02-08 14:42:59 +00:00
James Morse
1dd498e5e2 KVM: arm64: Workaround Cortex-A510's single-step and PAC trap errata
Cortex-A510's erratum #2077057 causes SPSR_EL2 to be corrupted when
single-stepping authenticated ERET instructions. A single step is
expected, but a pointer authentication trap is taken instead. The
erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow
EL1 to cause a return to EL2 with a guest controlled ELR_EL2.

Because the conditions require an ERET into active-not-pending state,
this is only a problem for the EL2 when EL2 is stepping EL1. In this case
the previous SPSR_EL2 value is preserved in struct kvm_vcpu, and can be
restored.

Cc: stable@vger.kernel.org # 53960faf2b: arm64: Add Cortex-A510 CPU part definition
Cc: stable@vger.kernel.org
Signed-off-by: James Morse <james.morse@arm.com>
[maz: fixup cpucaps ordering]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220127122052.1584324-5-james.morse@arm.com
2022-02-03 09:22:30 +00:00
James Morse
1c71dbc8a1 KVM: arm64: Avoid consuming a stale esr value when SError occur
When any exception other than an IRQ occurs, the CPU updates the ESR_EL2
register with the exception syndrome. An SError may also become pending,
and will be synchronised by KVM. KVM notes the exception type, and whether
an SError was synchronised in exit_code.

When an exception other than an IRQ occurs, fixup_guest_exit() updates
vcpu->arch.fault.esr_el2 from the hardware register. When an SError was
synchronised, the vcpu esr value is used to determine if the exception
was due to an HVC. If so, ELR_EL2 is moved back one instruction. This
is so that KVM can process the SError first, and re-execute the HVC if
the guest survives the SError.

But if an IRQ synchronises an SError, the vcpu's esr value is stale.
If the previous non-IRQ exception was an HVC, KVM will corrupt ELR_EL2,
causing an unrelated guest instruction to be executed twice.

Check ARM_EXCEPTION_CODE() before messing with ELR_EL2, IRQs don't
update this register so don't need to check.

Fixes: defe21f49b ("KVM: arm64: Move PC rollback on SError to HYP")
Cc: stable@vger.kernel.org
Reported-by: Steven Price <steven.price@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220127122052.1584324-3-james.morse@arm.com
2022-02-03 09:20:05 +00:00
Paolo Bonzini
7fd55a02a4 Merge tag 'kvmarm-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/arm64 updates for Linux 5.16

- Simplification of the 'vcpu first run' by integrating it into
  KVM's 'pid change' flow

- Refactoring of the FP and SVE state tracking, also leading to
  a simpler state and less shared data between EL1 and EL2 in
  the nVHE case

- Tidy up the header file usage for the nvhe hyp object

- New HYP unsharing mechanism, finally allowing pages to be
  unmapped from the Stage-1 EL2 page-tables

- Various pKVM cleanups around refcounting and sharing

- A couple of vgic fixes for bugs that would trigger once
  the vcpu xarray rework is merged, but not sooner

- Add minimal support for ARMv8.7's PMU extension

- Rework kvm_pgtable initialisation ahead of the NV work

- New selftest for IRQ injection

- Teach selftests about the lack of default IPA space and
  page sizes

- Expand sysreg selftest to deal with Pointer Authentication

- The usual bunch of cleanups and doc update
2022-01-07 10:42:19 -05:00
Marc Zyngier
43d8ac2212 Merge branch kvm-arm64/pkvm-hyp-sharing into kvmarm-master/next
* kvm-arm64/pkvm-hyp-sharing:
  : .
  : Series from Quentin Perret, implementing HYP page share/unshare:
  :
  : This series implements an unshare hypercall at EL2 in nVHE
  : protected mode, and makes use of it to unmmap guest-specific
  : data-structures from EL2 stage-1 during guest tear-down.
  : Crucially, the implementation of the share and unshare
  : routines use page refcounts in the host kernel to avoid
  : accidentally unmapping data-structures that overlap a common
  : page.
  : [...]
  : .
  KVM: arm64: pkvm: Unshare guest structs during teardown
  KVM: arm64: Expose unshare hypercall to the host
  KVM: arm64: Implement do_unshare() helper for unsharing memory
  KVM: arm64: Implement __pkvm_host_share_hyp() using do_share()
  KVM: arm64: Implement do_share() helper for sharing memory
  KVM: arm64: Introduce wrappers for host and hyp spin lock accessors
  KVM: arm64: Extend pkvm_page_state enumeration to handle absent pages
  KVM: arm64: pkvm: Refcount the pages shared with EL2
  KVM: arm64: Introduce kvm_share_hyp()
  KVM: arm64: Implement kvm_pgtable_hyp_unmap() at EL2
  KVM: arm64: Hook up ->page_count() for hypervisor stage-1 page-table
  KVM: arm64: Fixup hyp stage-1 refcount
  KVM: arm64: Refcount hyp stage-1 pgtable pages
  KVM: arm64: Provide {get,put}_page() stubs for early hyp allocator

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-12-16 13:06:09 +00:00
Will Deacon
b8cc6eb5bd KVM: arm64: Expose unshare hypercall to the host
Introduce an unshare hypercall which can be used to unmap memory from
the hypervisor stage-1 in nVHE protected mode. This will be useful to
update the EL2 ownership state of pages during guest teardown, and
avoids keeping dangling mappings to unreferenced portions of memory.

Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211215161232.1480836-14-qperret@google.com
2021-12-16 12:58:57 +00:00
Will Deacon
3d467f7b8c KVM: arm64: Extend pkvm_page_state enumeration to handle absent pages
Explicitly name the combination of SW0 | SW1 as reserved in the pte and
introduce a new PKVM_NOPAGE meta-state which, although not directly
stored in the software bits of the pte, can be used to represent an
entry for which there is no underlying page. This is distinct from an
invalid pte, as stage-2 identity mappings for the host are created
lazily and so an invalid pte there is the same as a valid mapping for
the purposes of ownership information.

This state will be used for permission checking during page transitions
in later patches.

Reviewed-by: Andrew Walbran <qwandor@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211215161232.1480836-9-qperret@google.com
2021-12-16 12:58:56 +00:00
Marc Zyngier
7b6871f670 Merge branch kvm-arm64/pkvm-cleanups-5.17 into kvmarm-master/next
* kvm-arm64/pkvm-cleanups-5.17:
  : .
  : pKVM cleanups from Quentin Perret:
  :
  : This series is a collection of various fixes and cleanups for KVM/arm64
  : when running in nVHE protected mode. The first two patches are real
  : fixes/improvements, the following two are minor cleanups, and the last
  : two help satisfy my paranoia so they're certainly optional.
  : .
  KVM: arm64: pkvm: Make kvm_host_owns_hyp_mappings() robust to VHE
  KVM: arm64: pkvm: Stub io map functions
  KVM: arm64: Make __io_map_base static
  KVM: arm64: Make the hyp memory pool static
  KVM: arm64: pkvm: Disable GICv2 support
  KVM: arm64: pkvm: Fix hyp_pool max order

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-12-15 14:21:23 +00:00
Quentin Perret
473a3efbaf KVM: arm64: Make __io_map_base static
The __io_map_base variable is used at EL2 to track the end of the
hypervisor's "private" VA range in nVHE protected mode. However it
doesn't need to be used outside of mm.c, so let's make it static to keep
all the hyp VA allocation logic in one place.

Signed-off-by: Quentin Perret <qperret@google.com>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211208152300.2478542-5-qperret@google.com
2021-12-15 14:17:30 +00:00
Quentin Perret
53a563b01f KVM: arm64: Make the hyp memory pool static
The hyp memory pool struct is sized to fit exactly the needs of the
hypervisor stage-1 page-table allocator, so it is important it is not
used for anything else. As it is currently used only from setup.c,
reduce its visibility by marking it static.

Signed-off-by: Quentin Perret <qperret@google.com>
Reviewed-by: Andrew Walbran <qwandor@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211208152300.2478542-4-qperret@google.com
2021-12-15 14:17:01 +00:00
Marc Zyngier
370a17f531 Merge branch kvm-arm64/hyp-header-split into kvmarm-master/next
* kvm-arm64/hyp-header-split:
  : .
  : Tidy up the header file usage for the nvhe hyp object so
  : that header files under arch/arm64/kvm/hyp/include are not
  : included by host code running at EL1.
  : .
  KVM: arm64: Move host EL1 code out of hyp/ directory
  KVM: arm64: Generate hyp_constants.h for the host
  arm64: Add missing include of asm/cpufeature.h to asm/mmu.h

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-12-07 09:14:49 +00:00
Will Deacon
9429f4b041 KVM: arm64: Move host EL1 code out of hyp/ directory
kvm/hyp/reserved_mem.c contains host code executing at EL1 and is not
linked into the hypervisor object. Move the file into kvm/pkvm.c and
rework the headers so that the definitions shared between the host and
the hypervisor live in asm/kvm_pkvm.h.

Signed-off-by: Will Deacon <will@kernel.org>
Tested-by: Fuad Tabba <tabba@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211202171048.26924-4-will@kernel.org
2021-12-06 08:37:03 +00:00
Marc Zyngier
7183b2b5ae KVM: arm64: Move pkvm's special 32bit handling into a generic infrastructure
Protected KVM is trying to turn AArch32 exceptions into an illegal
exception entry. Unfortunately, it does that in a way that is a bit
abrupt, and too early for PSTATE to be available.

Instead, move it to the fixup code, which is a more reasonable place
for it. This will also be useful for the NV code.

Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-11-24 13:30:50 +00:00
Marc Zyngier
83bb2c1a01 KVM: arm64: Save PSTATE early on exit
In order to be able to use primitives such as vcpu_mode_is_32bit(),
we need to synchronize the guest PSTATE. However, this is currently
done deep into the bowels of the world-switch code, and we do have
helpers evaluating this much earlier (__vgic_v3_perform_cpuif_access
and handle_aarch32_guest, for example).

Move the saving of the guest pstate into the early fixups, which
cures the first issue. The second one will be addressed separately.

Tested-by: Fuad Tabba <tabba@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-11-24 13:30:01 +00:00
Marc Zyngier
bee14bca73 KVM: arm64: Stop mapping current thread_info at EL2
Now that we can track an equivalent of TIF_FOREIGN_FPSTATE, drop
the mapping of current's thread_info at EL2.

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-11-22 16:01:39 +00:00
Marc Zyngier
af9a0e21d8 KVM: arm64: Introduce flag shadowing TIF_FOREIGN_FPSTATE
We currently have to maintain a mapping the thread_info structure
at EL2 in order to be able to check the TIF_FOREIGN_FPSTATE flag.

In order to eventually get rid of this, start with a vcpu flag that
shadows the thread flag on each entry into the hypervisor.

Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-11-22 16:01:39 +00:00
Marc Zyngier
8383741ab2 KVM: arm64: Get rid of host SVE tracking/saving
The SVE host tracking in KVM is pretty involved. It relies on a
set of flags tracking the ownership of the SVE register, as well
as that of the EL0 access.

It is also pretty scary: __hyp_sve_save_host() computes
a thread_struct pointer and obtains a sve_state which gets directly
accessed without further ado, even on nVHE. How can this even work?

The answer to that is that it doesn't, and that this is mostly dead
code. Closer examination shows that on executing a syscall, userspace
loses its SVE state entirely. This is part of the ABI. Another
thing to notice is that although the kernel provides helpers such as
kernel_neon_begin()/end(), they only deal with the FP/NEON state,
and not SVE.

Given that you can only execute a guest as the result of a syscall,
and that the kernel cannot use SVE by itself, it becomes pretty
obvious that there is never any host SVE state to save, and that
this code is only there to increase confusion.

Get rid of the TIF_SVE tracking and host save infrastructure altogether.

Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-11-22 15:30:27 +00:00
Linus Torvalds
d7e0a795bf Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
 "ARM:

   - More progress on the protected VM front, now with the full fixed
     feature set as well as the limitation of some hypercalls after
     initialisation.

   - Cleanup of the RAZ/WI sysreg handling, which was pointlessly
     complicated

   - Fixes for the vgic placement in the IPA space, together with a
     bunch of selftests

   - More memcg accounting of the memory allocated on behalf of a guest

   - Timer and vgic selftests

   - Workarounds for the Apple M1 broken vgic implementation

   - KConfig cleanups

   - New kvmarm.mode=none option, for those who really dislike us

  RISC-V:

   - New KVM port.

  x86:

   - New API to control TSC offset from userspace

   - TSC scaling for nested hypervisors on SVM

   - Switch masterclock protection from raw_spin_lock to seqcount

   - Clean up function prototypes in the page fault code and avoid
     repeated memslot lookups

   - Convey the exit reason to userspace on emulation failure

   - Configure time between NX page recovery iterations

   - Expose Predictive Store Forwarding Disable CPUID leaf

   - Allocate page tracking data structures lazily (if the i915 KVM-GT
     functionality is not compiled in)

   - Cleanups, fixes and optimizations for the shadow MMU code

  s390:

   - SIGP Fixes

   - initial preparations for lazy destroy of secure VMs

   - storage key improvements/fixes

   - Log the guest CPNC

  Starting from this release, KVM-PPC patches will come from Michael
  Ellerman's PPC tree"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (227 commits)
  RISC-V: KVM: fix boolreturn.cocci warnings
  RISC-V: KVM: remove unneeded semicolon
  RISC-V: KVM: Fix GPA passed to __kvm_riscv_hfence_gvma_xyz() functions
  RISC-V: KVM: Factor-out FP virtualization into separate sources
  KVM: s390: add debug statement for diag 318 CPNC data
  KVM: s390: pv: properly handle page flags for protected guests
  KVM: s390: Fix handle_sske page fault handling
  KVM: x86: SGX must obey the KVM_INTERNAL_ERROR_EMULATION protocol
  KVM: x86: On emulation failure, convey the exit reason, etc. to userspace
  KVM: x86: Get exit_reason as part of kvm_x86_ops.get_exit_info
  KVM: x86: Clarify the kvm_run.emulation_failure structure layout
  KVM: s390: Add a routine for setting userspace CPU state
  KVM: s390: Simplify SIGP Set Arch handling
  KVM: s390: pv: avoid stalls when making pages secure
  KVM: s390: pv: avoid stalls for kvm_s390_pv_init_vm
  KVM: s390: pv: avoid double free of sida page
  KVM: s390: pv: add macros for UVC CC values
  s390/mm: optimize reset_guest_reference_bit()
  s390/mm: optimize set_guest_storage_key()
  s390/mm: no need for pte_alloc_map_lock() if we know the pmd is present
  ...
2021-11-02 11:24:14 -07:00
Linus Torvalds
46f8763228 Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
 "There's the usual summary below, but the highlights are support for
  the Armv8.6 timer extensions, KASAN support for asymmetric MTE, the
  ability to kexec() with the MMU enabled and a second attempt at
  switching to the generic pfn_valid() implementation.

  Summary:

   - Support for the Arm8.6 timer extensions, including a
     self-synchronising view of the system registers to elide some
     expensive ISB instructions.

   - Exception table cleanup and rework so that the fixup handlers
     appear correctly in backtraces.

   - A handful of miscellaneous changes, the main one being selection of
     CONFIG_HAVE_POSIX_CPU_TIMERS_TASK_WORK.

   - More mm and pgtable cleanups.

   - KASAN support for "asymmetric" MTE, where tag faults are reported
     synchronously for loads (via an exception) and asynchronously for
     stores (via a register).

   - Support for leaving the MMU enabled during kexec relocation, which
     significantly speeds up the operation.

   - Minor improvements to our perf PMU drivers.

   - Improvements to the compat vDSO build system, particularly when
     building with LLVM=1.

   - Preparatory work for handling some Coresight TRBE tracing errata.

   - Cleanup and refactoring of the SVE code to pave the way for SME
     support in future.

   - Ensure SCS pages are unpoisoned immediately prior to freeing them
     when KASAN is enabled for the vmalloc area.

   - Try moving to the generic pfn_valid() implementation again now that
     the DMA mapping issue from last time has been resolved.

   - Numerous improvements and additions to our FPSIMD and SVE
     selftests"

[ armv8.6 timer updates were in a shared branch and already came in
  through -tip in the timer pull  - Linus ]

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (85 commits)
  arm64: Select POSIX_CPU_TIMERS_TASK_WORK
  arm64: Document boot requirements for FEAT_SME_FA64
  arm64/sve: Fix warnings when SVE is disabled
  arm64/sve: Add stub for sve_max_virtualisable_vl()
  arm64: errata: Add detection for TRBE write to out-of-range
  arm64: errata: Add workaround for TSB flush failures
  arm64: errata: Add detection for TRBE overwrite in FILL mode
  arm64: Add Neoverse-N2, Cortex-A710 CPU part definition
  selftests: arm64: Factor out utility functions for assembly FP tests
  arm64: vmlinux.lds.S: remove `.fixup` section
  arm64: extable: add load_unaligned_zeropad() handler
  arm64: extable: add a dedicated uaccess handler
  arm64: extable: add `type` and `data` fields
  arm64: extable: use `ex` for `exception_table_entry`
  arm64: extable: make fixup_exception() return bool
  arm64: extable: consolidate definitions
  arm64: gpr-num: support W registers
  arm64: factor out GPR numbering helpers
  arm64: kvm: use kvm_exception_table_entry
  arm64: lib: __arch_copy_to_user(): fold fixups into body
  ...
2021-11-01 16:33:53 -07:00
Paolo Bonzini
4e33868433 Merge tag 'kvmarm-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/arm64 updates for Linux 5.16

- More progress on the protected VM front, now with the full
  fixed feature set as well as the limitation of some hypercalls
  after initialisation.

- Cleanup of the RAZ/WI sysreg handling, which was pointlessly
  complicated

- Fixes for the vgic placement in the IPA space, together with a
  bunch of selftests

- More memcg accounting of the memory allocated on behalf of a guest

- Timer and vgic selftests

- Workarounds for the Apple M1 broken vgic implementation

- KConfig cleanups

- New kvmarm.mode=none option, for those who really dislike us
2021-10-31 02:28:48 -04:00
Mark Rutland
ae2b2f3384 arm64: kvm: use kvm_exception_table_entry
In subsequent patches we'll alter `struct exception_table_entry`, adding
fields that are not needed for KVM exception fixups.

In preparation for this, migrate KVM to its own `struct
kvm_exception_table_entry`, which is identical to the current format of
`struct exception_table_entry`. Comments are updated accordingly.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Alexandru Elisei <alexandru.elisei@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211019160219.5202-5-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-10-21 10:45:21 +01:00
Marc Zyngier
0c7639cc83 KVM: arm64: pkvm: Pass vpcu instead of kvm to kvm_get_exit_handler_array()
Passing a VM pointer around is odd, and results in extra work on
VHE. Follow the rest of the design that uses the vcpu instead, and
let the nVHE code look into the struct kvm as required.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Fuad Tabba <tabba@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20211013120346.2926621-11-maz@kernel.org
2021-10-18 16:57:09 +01:00
Marc Zyngier
746bdeadc5 KVM: arm64: pkvm: Move kvm_handle_pvm_restricted around
Place kvm_handle_pvm_restricted() next to its little friends such
as kvm_handle_pvm_sysreg().

This allows to make inject_undef64() static.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Fuad Tabba <tabba@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20211013120346.2926621-10-maz@kernel.org
2021-10-18 16:57:09 +01:00
Marc Zyngier
3061725d16 KVM: arm64: pkvm: Consolidate include files
kvm_fixed_config.h is pkvm specific, and would be better placed
near its users. At the same time, include/nvhe/sys_regs.h is now
almost empty.

Merge the two into arch/arm64/kvm/hyp/include/nvhe/fixed_config.h.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Fuad Tabba <tabba@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20211013120346.2926621-9-maz@kernel.org
2021-10-18 16:57:09 +01:00
Marc Zyngier
ce75916749 KVM: arm64: pkvm: Use a single function to expose all id-regs
Rather than exposing a whole set of helper functions to retrieve
individual ID registers, use the existing decoding tree and expose
a single helper instead.

This allow a number of functions to be made static, and we now
have a single entry point to maintain.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20211013120346.2926621-3-maz@kernel.org
2021-10-18 16:57:08 +01:00
Marc Zyngier
8a049862c3 KVM: arm64: Fix early exit ptrauth handling
The previous rework of the early exit code to provide an EC-based
decoding tree missed the fact that we have two trap paths for
ptrauth: the instructions (EC_PAC) and the sysregs (EC_SYS64).

Rework the handlers to call the ptrauth handling code on both
paths.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Fuad Tabba <tabba@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20211013120346.2926621-2-maz@kernel.org
2021-10-18 16:57:08 +01:00
Fuad Tabba
2a0c343386 KVM: arm64: Initialize trap registers for protected VMs
Protected VMs have more restricted features that need to be
trapped. Moreover, the host should not be trusted to set the
appropriate trapping registers and their values.

Initialize the trapping registers, i.e., hcr_el2, mdcr_el2, and
cptr_el2 at EL2 for protected guests, based on the values of the
guest's feature id registers.

No functional change intended as trap handlers introduced in the
previous patch are still not hooked in to the guest exit
handlers.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211010145636.1950948-9-tabba@google.com
2021-10-11 14:57:29 +01:00
Fuad Tabba
6c30bfb18d KVM: arm64: Add handlers for protected VM System Registers
Add system register handlers for protected VMs. These cover Sys64
registers (including feature id registers), and debug.

No functional change intended as these are not hooked in yet to
the guest exit handlers introduced earlier. So when trapping is
triggered, the exit handlers let the host handle it, as before.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211010145636.1950948-8-tabba@google.com
2021-10-11 14:57:29 +01:00
Fuad Tabba
3b1a690eda KVM: arm64: Pass struct kvm to per-EC handlers
We need struct kvm to check for protected VMs to be able to pick
the right handlers for them in subsequent patches.

Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211010145636.1950948-5-tabba@google.com
2021-10-11 14:57:28 +01:00
Marc Zyngier
8fb2046180 KVM: arm64: Move early handlers to per-EC handlers
Simplify the early exception handling by slicing the gigantic decoding
tree into a more manageable set of functions, similar to what we have
in handle_exit.c.

This will also make the structure reusable for pKVM's own early exit
handling.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20211010145636.1950948-4-tabba@google.com
2021-10-11 14:57:28 +01:00
Marc Zyngier
7dd9b5a157 KVM: arm64: Move __get_fault_info() and co into their own include file
In order to avoid including the whole of the switching helpers
in unrelated files, move the __get_fault_info() and related helpers
into their own include file.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20211010145636.1950948-2-tabba@google.com
2021-10-11 14:57:27 +01:00
Quentin Perret
1d58a17ef5 KVM: arm64: Fix host stage-2 PGD refcount
The KVM page-table library refcounts the pages of concatenated stage-2
PGDs individually. However, when running KVM in protected mode, the
host's stage-2 PGD is currently managed by EL2 as a single high-order
compound page, which can cause the refcount of the tail pages to reach 0
when they shouldn't, hence corrupting the page-table.

Fix this by introducing a new hyp_split_page() helper in the EL2 page
allocator (matching the kernel's split_page() function), and make use of
it from host_s2_zalloc_pages_exact().

Fixes: 1025c8c0c6 ("KVM: arm64: Wrap the host with a stage 2")
Acked-by: Will Deacon <will@kernel.org>
Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211005090155.734578-5-qperret@google.com
2021-10-05 13:02:54 +01:00
Marc Zyngier
7c7b363d62 Merge branch kvm-arm64/pkvm-fixed-features-prologue into kvmarm-master/next
* kvm-arm64/pkvm-fixed-features-prologue:
  : Rework a bunch of common infrastructure as a prologue
  : to Fuad Tabba's protected VM fixed feature series.
  KVM: arm64: Upgrade trace_kvm_arm_set_dreg32() to 64bit
  KVM: arm64: Add config register bit definitions
  KVM: arm64: Add feature register flag definitions
  KVM: arm64: Track value of cptr_el2 in struct kvm_vcpu_arch
  KVM: arm64: Keep mdcr_el2's value as set by __init_el2_debug
  KVM: arm64: Restore mdcr_el2 from vcpu
  KVM: arm64: Refactor sys_regs.h,c for nVHE reuse
  KVM: arm64: Fix names of config register fields
  KVM: arm64: MDCR_EL2 is a 64-bit register
  KVM: arm64: Remove trailing whitespace in comment
  KVM: arm64: placeholder to check if VM is protected

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-08-20 12:23:53 +01:00
Marc Zyngier
deb151a582 Merge branch kvm-arm64/mmu/vmid-cleanups into kvmarm-master/next
* kvm-arm64/mmu/vmid-cleanups:
  : Cleanup the stage-2 configuration by providing a single helper,
  : and tidy up some of the ordering requirements for the VMID
  : allocator.
  KVM: arm64: Upgrade VMID accesses to {READ,WRITE}_ONCE
  KVM: arm64: Unify stage-2 programming behind __load_stage2()
  KVM: arm64: Move kern_hyp_va() usage in __load_guest_stage2() into the callers

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-08-20 12:23:15 +01:00
Fuad Tabba
1460b4b25f KVM: arm64: Restore mdcr_el2 from vcpu
On deactivating traps, restore the value of mdcr_el2 from the
newly created and preserved host value vcpu context, rather than
directly reading the hardware register.

Up until and including this patch the two values are the same,
i.e., the hardware register and the vcpu one. A future patch will
be changing the value of mdcr_el2 on activating traps, and this
ensures that its value will be restored.

No functional change intended.

Signed-off-by: Fuad Tabba <tabba@google.com>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210817081134.2918285-7-tabba@google.com
2021-08-20 11:12:17 +01:00
Marc Zyngier
4efc0ede4f KVM: arm64: Unify stage-2 programming behind __load_stage2()
The protected mode relies on a separate helper to load the
S2 context. Move over to the __load_guest_stage2() helper
instead, and rename it to __load_stage2() to present a unified
interface.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Jade Alglave <jade.alglave@arm.com>
Cc: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210806113109.2475-5-will@kernel.org
2021-08-20 09:11:28 +01:00
Quentin Perret
64a80fb766 KVM: arm64: Make __pkvm_create_mappings static
The __pkvm_create_mappings() function is no longer used outside of
nvhe/mm.c, make it static.

Signed-off-by: Quentin Perret <qperret@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210809152448.1810400-22-qperret@google.com
2021-08-11 11:39:52 +01:00
Quentin Perret
66c57edd3b KVM: arm64: Restrict EL2 stage-1 changes in protected mode
The host kernel is currently able to change EL2 stage-1 mappings without
restrictions thanks to the __pkvm_create_mappings() hypercall. But in a
world where the host is no longer part of the TCB, this clearly poses a
problem.

To fix this, introduce a new hypercall to allow the host to share a
physical memory page with the hypervisor, and remove the
__pkvm_create_mappings() variant. The new hypercall implements
ownership and permission checks before allowing the sharing operation,
and it annotates the shared page in the hypervisor stage-1 and host
stage-2 page-tables.

Signed-off-by: Quentin Perret <qperret@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210809152448.1810400-21-qperret@google.com
2021-08-11 11:39:52 +01:00
Quentin Perret
f9370010e9 KVM: arm64: Refactor protected nVHE stage-1 locking
Refactor the hypervisor stage-1 locking in nVHE protected mode to expose
a new pkvm_create_mappings_locked() function. This will be used in later
patches to allow walking and changing the hypervisor stage-1 without
releasing the lock.

Signed-off-by: Quentin Perret <qperret@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210809152448.1810400-20-qperret@google.com
2021-08-11 11:39:51 +01:00
Quentin Perret
ad0e0139a8 KVM: arm64: Remove __pkvm_mark_hyp
Now that we mark memory owned by the hypervisor in the host stage-2
during __pkvm_init(), we no longer need to rely on the host to
explicitly mark the hyp sections later on.

Remove the __pkvm_mark_hyp() hypercall altogether.

Signed-off-by: Quentin Perret <qperret@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210809152448.1810400-19-qperret@google.com
2021-08-11 11:39:51 +01:00