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Author SHA1 Message Date
Oliver Upton
1e5794295c KVM: arm64: Dedupe vCPU power off helpers
vcpu_power_off() and kvm_psci_vcpu_off() are equivalent; rename the
former and replace all callsites to the latter.

No functional change intended.

Signed-off-by: Oliver Upton <oupton@google.com>
Reviewed-by: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220504032446.4133305-3-oupton@google.com
2022-05-04 09:28:44 +01:00
Raghavendra Rao Ananta
05714cab7d KVM: arm64: Setup a framework for hypercall bitmap firmware registers
KVM regularly introduces new hypercall services to the guests without
any consent from the userspace. This means, the guests can observe
hypercall services in and out as they migrate across various host
kernel versions. This could be a major problem if the guest
discovered a hypercall, started using it, and after getting migrated
to an older kernel realizes that it's no longer available. Depending
on how the guest handles the change, there's a potential chance that
the guest would just panic.

As a result, there's a need for the userspace to elect the services
that it wishes the guest to discover. It can elect these services
based on the kernels spread across its (migration) fleet. To remedy
this, extend the existing firmware pseudo-registers, such as
KVM_REG_ARM_PSCI_VERSION, but by creating a new COPROC register space
for all the hypercall services available.

These firmware registers are categorized based on the service call
owners, but unlike the existing firmware pseudo-registers, they hold
the features supported in the form of a bitmap.

During the VM initialization, the registers are set to upper-limit of
the features supported by the corresponding registers. It's expected
that the VMMs discover the features provided by each register via
GET_ONE_REG, and write back the desired values using SET_ONE_REG.
KVM allows this modification only until the VM has started.

Some of the standard features are not mapped to any bits of the
registers. But since they can recreate the original problem of
making it available without userspace's consent, they need to
be explicitly added to the case-list in
kvm_hvc_call_default_allowed(). Any function-id that's not enabled
via the bitmap, or not listed in kvm_hvc_call_default_allowed, will
be returned as SMCCC_RET_NOT_SUPPORTED to the guest.

Older userspace code can simply ignore the feature and the
hypercall services will be exposed unconditionally to the guests,
thus ensuring backward compatibility.

In this patch, the framework adds the register only for ARM's standard
secure services (owner value 4). Currently, this includes support only
for ARM True Random Number Generator (TRNG) service, with bit-0 of the
register representing mandatory features of v1.0. Other services are
momentarily added in the upcoming patches.

Signed-off-by: Raghavendra Rao Ananta <rananta@google.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
[maz: reduced the scope of some helpers, tidy-up bitmap max values,
 dropped error-only fast path]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220502233853.1233742-3-rananta@google.com
2022-05-03 21:30:19 +01:00
Sean Christopherson
f502cc568d KVM: Add max_vcpus field in common 'struct kvm'
For TDX guests, the maximum number of vcpus needs to be specified when the
TDX guest VM is initialized (creating the TDX data corresponding to TDX
guest) before creating vcpu.  It needs to record the maximum number of
vcpus on VM creation (KVM_CREATE_VM) and return error if the number of
vcpus exceeds it

Because there is already max_vcpu member in arm64 struct kvm_arch, move it
to common struct kvm and initialize it to KVM_MAX_VCPUS before
kvm_arch_init_vm() instead of adding it to x86 struct kvm_arch.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Message-Id: <e53234cdee6a92357d06c80c03d77c19cdefb804.1646422845.git.isaku.yamahata@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-05-02 11:42:42 -04:00
Alexandru Elisei
18f3976fdb KVM: arm64: uapi: Add kvm_debug_exit_arch.hsr_high
When userspace is debugging a VM, the kvm_debug_exit_arch part of the
kvm_run struct contains arm64 specific debug information: the ESR_EL2
value, encoded in the field "hsr", and the address of the instruction
that caused the exception, encoded in the field "far".

Linux has moved to treating ESR_EL2 as a 64-bit register, but unfortunately
kvm_debug_exit_arch.hsr cannot be changed because that would change the
memory layout of the struct on big endian machines:

Current layout:			| Layout with "hsr" extended to 64 bits:
				|
offset 0: ESR_EL2[31:0] (hsr)   | offset 0: ESR_EL2[61:32] (hsr[61:32])
offset 4: padding		| offset 4: ESR_EL2[31:0]  (hsr[31:0])
offset 8: FAR_EL2[61:0] (far)	| offset 8: FAR_EL2[61:0]  (far)

which breaks existing code.

The padding is inserted by the compiler because the "far" field must be
aligned to 8 bytes (each field must be naturally aligned - aapcs64 [1],
page 18), and the struct itself must be aligned to 8 bytes (the struct must
be aligned to the maximum alignment of its fields - aapcs64, page 18),
which means that "hsr" must be aligned to 8 bytes as it is the first field
in the struct.

To avoid changing the struct size and layout for the existing fields, add a
new field, "hsr_high", which replaces the existing padding. "hsr_high" will
be used to hold the ESR_EL2[61:32] bits of the register. The memory layout,
both on big and little endian machine, becomes:

offset 0: ESR_EL2[31:0]  (hsr)
offset 4: ESR_EL2[61:32] (hsr_high)
offset 8: FAR_EL2[61:0]  (far)

The padding that the compiler inserts for the current struct layout is
unitialized. To prevent an updated userspace running on an old kernel
mistaking the padding for a valid "hsr_high" value, add a new flag,
KVM_DEBUG_ARCH_HSR_HIGH_VALID, to kvm_run->flags to let userspace know that
"hsr_high" holds a valid ESR_EL2[61:32] value.

[1] https://github.com/ARM-software/abi-aa/releases/download/2021Q3/aapcs64.pdf

Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220425114444.368693-6-alexandru.elisei@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-04-29 19:26:27 +01:00
Kalesh Singh
ce3354318a KVM: arm64: Add guard pages for KVM nVHE hypervisor stack
Map the stack pages in the flexible private VA range and allocate
guard pages below the stack as unbacked VA space. The stack is aligned
so that any valid stack address has PAGE_SHIFT bit as 1 - this is used
for overflow detection (implemented in a subsequent patch in the series).

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/20220420214317.3303360-4-kaleshsingh@google.com
2022-04-28 20:53:13 +01:00
Marc Zyngier
89f5074c50 KVM: arm64: Handle blocking WFIT instruction
When trapping a blocking WFIT instruction, take it into account when
computing the deadline of the background timer.

The state is tracked with a new vcpu flag, and is gated by a new
CPU capability, which isn't currently enabled.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220419182755.601427-6-maz@kernel.org
2022-04-20 13:24:45 +01:00
Marc Zyngier
b57de4ffd7 KVM: arm64: Simplify kvm_cpu_has_pending_timer()
kvm_cpu_has_pending_timer() ends up checking all the possible
timers for a wake-up cause. However, we already check for
pending interrupts whenever we try to wake-up a vcpu, including
the timer interrupts.

Obviously, doing the same work twice is once too many. Reduce
this helper to almost nothing, but keep it around, as we are
going to make use of it soon.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220419182755.601427-4-maz@kernel.org
2022-04-20 13:24:44 +01:00
Linus Torvalds
1ebdbeb03e 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
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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
Julia Lawall
21ea457842 KVM: arm64: fix typos in comments
Various spelling mistakes in comments.
Detected with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220318103729.157574-24-Julia.Lawall@inria.fr
2022-03-18 14:04:15 +00:00
Marc Zyngier
06394531b4 KVM: arm64: Generalise VM features into a set of flags
We currently deal with a set of booleans for VM features,
while they could be better represented as set of flags
contained in an unsigned long, similarily to what we are
doing on the CPU side.

Signed-off-by: Marc Zyngier <maz@kernel.org>
[Oliver: Flag-ify the 'ran_once' boolean]
Signed-off-by: Oliver Upton <oupton@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220311174001.605719-2-oupton@google.com
2022-03-18 14:02:33 +00:00
Will Deacon
641d804157 Merge branch 'for-next/spectre-bhb' into for-next/core
Merge in the latest Spectre mess to fix up conflicts with what was
already queued for 5.18 when the embargo finally lifted.

* for-next/spectre-bhb: (21 commits)
  arm64: Do not include __READ_ONCE() block in assembly files
  arm64: proton-pack: Include unprivileged eBPF status in Spectre v2 mitigation reporting
  arm64: Use the clearbhb instruction in mitigations
  KVM: arm64: Allow SMCCC_ARCH_WORKAROUND_3 to be discovered and migrated
  arm64: Mitigate spectre style branch history side channels
  arm64: proton-pack: Report Spectre-BHB vulnerabilities as part of Spectre-v2
  arm64: Add percpu vectors for EL1
  arm64: entry: Add macro for reading symbol addresses from the trampoline
  arm64: entry: Add vectors that have the bhb mitigation sequences
  arm64: entry: Add non-kpti __bp_harden_el1_vectors for mitigations
  arm64: entry: Allow the trampoline text to occupy multiple pages
  arm64: entry: Make the kpti trampoline's kpti sequence optional
  arm64: entry: Move trampoline macros out of ifdef'd section
  arm64: entry: Don't assume tramp_vectors is the start of the vectors
  arm64: entry: Allow tramp_alias to access symbols after the 4K boundary
  arm64: entry: Move the trampoline data page before the text page
  arm64: entry: Free up another register on kpti's tramp_exit path
  arm64: entry: Make the trampoline cleanup optional
  KVM: arm64: Allow indirect vectors to be used without SPECTRE_V3A
  arm64: spectre: Rename spectre_v4_patch_fw_mitigation_conduit
  ...
2022-03-14 19:08:31 +00:00
Marc Zyngier
7297a8bcc0 Merge branch kvm-arm64/misc-5.18 into kvmarm-master/next
* kvm-arm64/misc-5.18:
  : .
  : Misc fixes for KVM/arm64 5.18:
  :
  : - Drop unused kvm parameter to kvm_psci_version()
  :
  : - Implement CONFIG_DEBUG_LIST at EL2
  :
  : - Make CONFIG_ARM64_ERRATUM_2077057 default y
  :
  : - Only do the interrupt dance if we have exited because of an interrupt
  :
  : - Remove traces of 32bit ARM host support from the documentation
  : .
  Documentation: KVM: Update documentation to indicate KVM is arm64-only
  KVM: arm64: Only open the interrupt window on exit due to an interrupt
  KVM: arm64: Enable Cortex-A510 erratum 2077057 by default

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-03-09 11:16:48 +00:00
Marc Zyngier
f7659f8bcd KVM: arm64: Only open the interrupt window on exit due to an interrupt
Now that we properly account for interrupts taken whilst the guest
was running, it becomes obvious that there is no need to open
this accounting window if we didn't exit because of an interrupt.

This saves a number of system register accesses and other barriers
if we exited for any other reason (such as a trap, for example).

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20220304135914.1464721-1-maz@kernel.org
2022-03-04 15:07:04 +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
James Morse
5bdf343760 KVM: arm64: Allow indirect vectors to be used without SPECTRE_V3A
CPUs vulnerable to Spectre-BHB either need to make an SMC-CC firmware
call from the vectors, or run a sequence of branches. This gets added
to the hyp vectors. If there is no support for arch-workaround-1 in
firmware, the indirect vector will be used.

kvm_init_vector_slots() only initialises the two indirect slots if
the platform is vulnerable to Spectre-v3a. pKVM's hyp_map_vectors()
only initialises __hyp_bp_vect_base if the platform is vulnerable to
Spectre-v3a.

As there are about to more users of the indirect vectors, ensure
their entries in hyp_spectre_vector_selector[] are always initialised,
and __hyp_bp_vect_base defaults to the regular VA mapping.

The Spectre-v3a check is moved to a helper
kvm_system_needs_idmapped_vectors(), and merged with the code
that creates the hyp mappings.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
2022-02-15 17:38:25 +00:00
Marc Zyngier
00e6dae00e Merge branch kvm-arm64/pmu-bl into kvmarm-master/next
* kvm-arm64/pmu-bl:
  : .
  : Improve PMU support on heterogeneous systems, courtesy of Alexandru Elisei
  : .
  KVM: arm64: Refuse to run VCPU if the PMU doesn't match the physical CPU
  KVM: arm64: Add KVM_ARM_VCPU_PMU_V3_SET_PMU attribute
  KVM: arm64: Keep a list of probed PMUs
  KVM: arm64: Keep a per-VM pointer to the default PMU
  perf: Fix wrong name in comment for struct perf_cpu_context
  KVM: arm64: Do not change the PMU event filter after a VCPU has run

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-02-08 17:54:41 +00:00
Alexandru Elisei
583cda1b0e KVM: arm64: Refuse to run VCPU if the PMU doesn't match the physical CPU
Userspace can assign a PMU to a VCPU with the KVM_ARM_VCPU_PMU_V3_SET_PMU
device ioctl. If the VCPU is scheduled on a physical CPU which has a
different PMU, the perf events needed to emulate a guest PMU won't be
scheduled in and the guest performance counters will stop counting. Treat
it as an userspace error and refuse to run the VCPU in this situation.

Suggested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220127161759.53553-7-alexandru.elisei@arm.com
2022-02-08 17:51:22 +00:00
Marc Zyngier
5177fe91e4 KVM: arm64: Do not change the PMU event filter after a VCPU has run
Userspace can specify which events a guest is allowed to use with the
KVM_ARM_VCPU_PMU_V3_FILTER attribute. The list of allowed events can be
identified by a guest from reading the PMCEID{0,1}_EL0 registers.

Changing the PMU event filter after a VCPU has run can cause reads of the
registers performed before the filter is changed to return different values
than reads performed with the new event filter in place. The architecture
defines the two registers as read-only, and this behaviour contradicts
that.

Keep track when the first VCPU has run and deny changes to the PMU event
filter to prevent this from happening.

Signed-off-by: Marc Zyngier <maz@kernel.org>
[ Alexandru E: Added commit message, updated ioctl documentation ]
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220127161759.53553-2-alexandru.elisei@arm.com
2022-02-08 17:51:21 +00:00
Shameer Kolothum
100b4f092f KVM: arm64: Make active_vmids invalid on vCPU schedule out
Like ASID allocator, we copy the active_vmids into the
reserved_vmids on a rollover. But it's unlikely that
every CPU will have a vCPU as current task and we may
end up unnecessarily reserving the VMID space.

Hence, set active_vmids to an invalid one when scheduling
out a vCPU.

Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211122121844.867-5-shameerali.kolothum.thodi@huawei.com
2022-02-08 14:57:04 +00:00
Julien Grall
3248136b36 KVM: arm64: Align the VMID allocation with the arm64 ASID
At the moment, the VMID algorithm will send an SGI to all the
CPUs to force an exit and then broadcast a full TLB flush and
I-Cache invalidation.

This patch uses the new VMID allocator. The benefits are:
   - Aligns with arm64 ASID algorithm.
   - CPUs are not forced to exit at roll-over. Instead,
     the VMID will be marked reserved and context invalidation
     is broadcasted. This will reduce the IPIs traffic.
   - More flexible to add support for pinned KVM VMIDs in
     the future.
   
With the new algo, the code is now adapted:
    - The call to update_vmid() will be done with preemption
      disabled as the new algo requires to store information
      per-CPU.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211122121844.867-4-shameerali.kolothum.thodi@huawei.com
2022-02-08 14:57:03 +00:00
Paolo Bonzini
7e6a6b400d KVM/arm64 fixes for 5.17, take #2
- A couple of fixes when handling an exception while a SError has been
   delivered
 
 - Workaround for Cortex-A510's single-step[ erratum
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Merge tag 'kvmarm-fixes-5.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 fixes for 5.17, take #2

- A couple of fixes when handling an exception while a SError has been
  delivered

- Workaround for Cortex-A510's single-step[ erratum
2022-02-05 00:58:25 -05:00
Mark Rutland
8cfe148a71 kvm/arm64: rework guest entry logic
In kvm_arch_vcpu_ioctl_run() we enter an RCU extended quiescent state
(EQS) by calling guest_enter_irqoff(), and unmasked IRQs prior to
exiting the EQS by calling guest_exit(). As the IRQ entry code will not
wake RCU in this case, we may run the core IRQ code and IRQ handler
without RCU watching, leading to various potential problems.

Additionally, we do not inform lockdep or tracing that interrupts will
be enabled during guest execution, which caan lead to misleading traces
and warnings that interrupts have been enabled for overly-long periods.

This patch fixes these issues by using the new timing and context
entry/exit helpers to ensure that interrupts are handled during guest
vtime but with RCU watching, with a sequence:

	guest_timing_enter_irqoff();

	guest_state_enter_irqoff();
	< run the vcpu >
	guest_state_exit_irqoff();

	< take any pending IRQs >

	guest_timing_exit_irqoff();

Since instrumentation may make use of RCU, we must also ensure that no
instrumented code is run during the EQS. I've split out the critical
section into a new kvm_arm_enter_exit_vcpu() helper which is marked
noinstr.

Fixes: 1b3d546daf ("arm/arm64: KVM: Properly account for guest CPU time")
Reported-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Cc: Alexandru Elisei <alexandru.elisei@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: James Morse <james.morse@arm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Message-Id: <20220201132926.3301912-3-mark.rutland@arm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-02-01 12:53:11 -05:00
Linus Torvalds
79e06c4c49 RISCV:
- Use common KVM implementation of MMU memory caches
 
 - SBI v0.2 support for Guest
 
 - Initial KVM selftests support
 
 - Fix to avoid spurious virtual interrupts after clearing hideleg CSR
 
 - Update email address for Anup and Atish
 
 ARM:
 - 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
 
 s390:
 - fix sigp sense/start/stop/inconsistency
 
 - cleanups
 
 x86:
 - Clean up some function prototypes more
 
 - improved gfn_to_pfn_cache with proper invalidation, used by Xen emulation
 
 - add KVM_IRQ_ROUTING_XEN_EVTCHN and event channel delivery
 
 - completely remove potential TOC/TOU races in nested SVM consistency checks
 
 - update some PMCs on emulated instructions
 
 - Intel AMX support (joint work between Thomas and Intel)
 
 - large MMU cleanups
 
 - module parameter to disable PMU virtualization
 
 - cleanup register cache
 
 - first part of halt handling cleanups
 
 - Hyper-V enlightened MSR bitmap support for nested hypervisors
 
 Generic:
 - clean up Makefiles
 
 - introduce CONFIG_HAVE_KVM_DIRTY_RING
 
 - optimize memslot lookup using a tree
 
 - optimize vCPU array usage by converting to xarray
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "RISCV:

   - Use common KVM implementation of MMU memory caches

   - SBI v0.2 support for Guest

   - Initial KVM selftests support

   - Fix to avoid spurious virtual interrupts after clearing hideleg CSR

   - Update email address for Anup and Atish

  ARM:

   - 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

  s390:

   - fix sigp sense/start/stop/inconsistency

   - cleanups

  x86:

   - Clean up some function prototypes more

   - improved gfn_to_pfn_cache with proper invalidation, used by Xen
     emulation

   - add KVM_IRQ_ROUTING_XEN_EVTCHN and event channel delivery

   - completely remove potential TOC/TOU races in nested SVM consistency
     checks

   - update some PMCs on emulated instructions

   - Intel AMX support (joint work between Thomas and Intel)

   - large MMU cleanups

   - module parameter to disable PMU virtualization

   - cleanup register cache

   - first part of halt handling cleanups

   - Hyper-V enlightened MSR bitmap support for nested hypervisors

  Generic:

   - clean up Makefiles

   - introduce CONFIG_HAVE_KVM_DIRTY_RING

   - optimize memslot lookup using a tree

   - optimize vCPU array usage by converting to xarray"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (268 commits)
  x86/fpu: Fix inline prefix warnings
  selftest: kvm: Add amx selftest
  selftest: kvm: Move struct kvm_x86_state to header
  selftest: kvm: Reorder vcpu_load_state steps for AMX
  kvm: x86: Disable interception for IA32_XFD on demand
  x86/fpu: Provide fpu_sync_guest_vmexit_xfd_state()
  kvm: selftests: Add support for KVM_CAP_XSAVE2
  kvm: x86: Add support for getting/setting expanded xstate buffer
  x86/fpu: Add uabi_size to guest_fpu
  kvm: x86: Add CPUID support for Intel AMX
  kvm: x86: Add XCR0 support for Intel AMX
  kvm: x86: Disable RDMSR interception of IA32_XFD_ERR
  kvm: x86: Emulate IA32_XFD_ERR for guest
  kvm: x86: Intercept #NM for saving IA32_XFD_ERR
  x86/fpu: Prepare xfd_err in struct fpu_guest
  kvm: x86: Add emulation for IA32_XFD
  x86/fpu: Provide fpu_update_guest_xfd() for IA32_XFD emulation
  kvm: x86: Enable dynamic xfeatures at KVM_SET_CPUID2
  x86/fpu: Provide fpu_enable_guest_xfd_features() for KVM
  x86/fpu: Add guest support to xfd_enable_feature()
  ...
2022-01-16 16:15:14 +02:00
Linus Torvalds
8e5b0adeea Peter Zijlstra says:
"Cleanup of the perf/kvm interaction."
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Merge tag 'perf_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf updates from Borislav Petkov:
 "Cleanup of the perf/kvm interaction."

* tag 'perf_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Drop guest callback (un)register stubs
  KVM: arm64: Drop perf.c and fold its tiny bits of code into arm.c
  KVM: arm64: Hide kvm_arm_pmu_available behind CONFIG_HW_PERF_EVENTS=y
  KVM: arm64: Convert to the generic perf callbacks
  KVM: x86: Move Intel Processor Trace interrupt handler to vmx.c
  KVM: Move x86's perf guest info callbacks to generic KVM
  KVM: x86: More precisely identify NMI from guest when handling PMI
  KVM: x86: Drop current_vcpu for kvm_running_vcpu + kvm_arch_vcpu variable
  perf/core: Use static_call to optimize perf_guest_info_callbacks
  perf: Force architectures to opt-in to guest callbacks
  perf: Add wrappers for invoking guest callbacks
  perf/core: Rework guest callbacks to prepare for static_call support
  perf: Drop dead and useless guest "support" from arm, csky, nds32 and riscv
  perf: Stop pretending that perf can handle multiple guest callbacks
  KVM: x86: Register Processor Trace interrupt hook iff PT enabled in guest
  KVM: x86: Register perf callbacks after calling vendor's hardware_setup()
  perf: Protect perf_guest_cbs with RCU
2022-01-12 16:26:58 -08:00
Paolo Bonzini
7fd55a02a4 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
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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
Quentin Perret
52b28657eb KVM: arm64: pkvm: Unshare guest structs during teardown
Make use of the newly introduced unshare hypercall during guest teardown
to unmap guest-related data structures from the hyp stage-1.

Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211215161232.1480836-15-qperret@google.com
2021-12-16 12:58:57 +00:00
Quentin Perret
3f868e142c KVM: arm64: Introduce kvm_share_hyp()
The create_hyp_mappings() function can currently be called at any point
in time. However, its behaviour in protected mode changes widely
depending on when it is being called. Prior to KVM init, it is used to
create the temporary page-table used to bring-up the hypervisor, and
later on it is transparently turned into a 'share' hypercall when the
kernel has lost control over the hypervisor stage-1. In order to prepare
the ground for also unsharing pages with the hypervisor during guest
teardown, introduce a kvm_share_hyp() function to make it clear in which
places a share hypercall should be expected, as we will soon need a
matching unshare hypercall in all those places.

Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211215161232.1480836-7-qperret@google.com
2021-12-16 12:58:56 +00:00
Sean Christopherson
d92a5d1c6c KVM: Add helpers to wake/query blocking vCPU
Add helpers to wake and query a blocking vCPU.  In addition to providing
nice names, the helpers reduce the probability of KVM neglecting to use
kvm_arch_vcpu_get_wait().

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211009021236.4122790-20-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-12-08 04:24:54 -05:00
Sean Christopherson
91b99ea706 KVM: Rename kvm_vcpu_block() => kvm_vcpu_halt()
Rename kvm_vcpu_block() to kvm_vcpu_halt() in preparation for splitting
the actual "block" sequences into a separate helper (to be named
kvm_vcpu_block()).  x86 will use the standalone block-only path to handle
non-halt cases where the vCPU is not runnable.

Rename block_ns to halt_ns to match the new function name.

No functional change intended.

Reviewed-by: David Matlack <dmatlack@google.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211009021236.4122790-14-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-12-08 04:24:51 -05:00
Sean Christopherson
6109c5a6ab KVM: arm64: Move vGIC v4 handling for WFI out arch callback hook
Move the put and reload of the vGIC out of the block/unblock callbacks
and into a dedicated WFI helper.  Functionally, this is nearly a nop as
the block hook is called at the very beginning of kvm_vcpu_block(), and
the only code in kvm_vcpu_block() after the unblock hook is to update the
halt-polling controls, i.e. can only affect the next WFI.

Back when the arch (un)blocking hooks were added by commits 3217f7c25b
("KVM: Add kvm_arch_vcpu_{un}blocking callbacks) and d35268da66
("arm/arm64: KVM: arch_timer: Only schedule soft timer on vcpu_block"),
the hooks were invoked only when KVM was about to "block", i.e. schedule
out the vCPU.  The use case at the time was to schedule a timer in the
host based on the earliest timer in the guest in order to wake the
blocking vCPU when the emulated guest timer fired.  Commit accb99bcd0
("KVM: arm/arm64: Simplify bg_timer programming") reworked the timer
logic to be even more precise, by waiting until the vCPU was actually
scheduled out, and so move the timer logic from the (un)blocking hooks to
vcpu_load/put.

In the meantime, the hooks gained usage for enabling vGIC v4 doorbells in
commit df9ba95993 ("KVM: arm/arm64: GICv4: Use the doorbell interrupt
as an unblocking source"), and added related logic for the VMCR in commit
5eeaf10eec ("KVM: arm/arm64: Sync ICH_VMCR_EL2 back when about to block").

Finally, commit 07ab0f8d9a ("KVM: Call kvm_arch_vcpu_blocking early
into the blocking sequence") hoisted the (un)blocking hooks so that they
wrapped KVM's halt-polling logic in addition to the core "block" logic.

In other words, the original need for arch hooks to take action _only_
in the block path is long since gone.

Cc: Oliver Upton <oupton@google.com>
Cc: Marc Zyngier <maz@kernel.org>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211009021236.4122790-11-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-12-08 04:24:49 -05:00
Marc Zyngier
46808a4cb8 KVM: Use 'unsigned long' as kvm_for_each_vcpu()'s index
Everywhere we use kvm_for_each_vpcu(), we use an int as the vcpu
index. Unfortunately, we're about to move rework the iterator,
which requires this to be upgrade to an unsigned long.

Let's bite the bullet and repaint all of it in one go.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Message-Id: <20211116160403.4074052-7-maz@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-12-08 04:24:15 -05:00
Marc Zyngier
27592ae8db KVM: Move wiping of the kvm->vcpus array to common code
All architectures have similar loops iterating over the vcpus,
freeing one vcpu at a time, and eventually wiping the reference
off the vcpus array. They are also inconsistently taking
the kvm->lock mutex when wiping the references from the array.

Make this code common, which will simplify further changes.
The locking is dropped altogether, as this should only be called
when there is no further references on the kvm structure.

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Message-Id: <20211116160403.4074052-2-maz@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-12-08 04:24:13 -05:00
Marc Zyngier
2d761dbf7f Merge branch kvm-arm64/fpsimd-tracking into kvmarm-master/next
* kvm-arm64/fpsimd-tracking:
  : .
  : Simplify the handling of both the FP/SIMD and SVE state by
  : removing the need for mapping the thread at EL2, and by
  : dropping the tracking of the host's SVE state which is
  : always invalid by construction.
  : .
  arm64/fpsimd: Document the use of TIF_FOREIGN_FPSTATE by KVM
  KVM: arm64: Stop mapping current thread_info at EL2
  KVM: arm64: Introduce flag shadowing TIF_FOREIGN_FPSTATE
  KVM: arm64: Remove unused __sve_save_state
  KVM: arm64: Get rid of host SVE tracking/saving
  KVM: arm64: Reorder vcpu flag definitions

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-12-01 12:13:44 +00:00
Marc Zyngier
cc5705fb1b KVM: arm64: Drop vcpu->arch.has_run_once for vcpu->pid
With the transition to kvm_arch_vcpu_run_pid_change() to handle
the "run once" activities, it becomes obvious that has_run_once
is now an exact shadow of vcpu->pid.

Replace vcpu->arch.has_run_once with a new vcpu_has_run_once()
helper that directly checks for vcpu->pid, and get rid of the
now unused field.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-12-01 11:51:22 +00:00
Marc Zyngier
b5aa368abf KVM: arm64: Merge kvm_arch_vcpu_run_pid_change() and kvm_vcpu_first_run_init()
The kvm_arch_vcpu_run_pid_change() helper gets called on each PID
change. The kvm_vcpu_first_run_init() helper gets run on the...
first run(!) of a vcpu.

As it turns out, the first run of a vcpu also triggers a PID change
event (vcpu->pid is initially NULL).

Use this property to merge these two helpers and get rid of another
arm64-specific oddity.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-12-01 11:51:21 +00:00
Marc Zyngier
1408e73d21 KVM: arm64: Restructure the point where has_run_once is advertised
Restructure kvm_vcpu_first_run_init() to set the has_run_once
flag after having completed all the "run once" activities.

This includes moving the flip of the userspace irqchip static key
to a point where nothing can fail.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-12-01 11:51:21 +00:00
Marc Zyngier
052f064d42 KVM: arm64: Move kvm_arch_vcpu_run_pid_change() out of line
Having kvm_arch_vcpu_run_pid_change() inline doesn't bring anything
to the table. Move it next to kvm_vcpu_first_run_init(), which will
be convenient for what is next to come.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-12-01 11:51:21 +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
Vitaly Kuznetsov
f60a00d729 KVM: arm64: Cap KVM_CAP_NR_VCPUS by kvm_arm_default_max_vcpus()
Generally, it doesn't make sense to return the recommended maximum number
of vCPUs which exceeds the maximum possible number of vCPUs.

Note: ARM64 is special as the value returned by KVM_CAP_MAX_VCPUS differs
depending on whether it is a system-wide ioctl or a per-VM one. Previously,
KVM_CAP_NR_VCPUS didn't have this difference and it seems preferable to
keep the status quo. Cap KVM_CAP_NR_VCPUS by kvm_arm_default_max_vcpus()
which is what gets returned by system-wide KVM_CAP_MAX_VCPUS.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211116163443.88707-2-vkuznets@redhat.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-11-18 02:12:14 -05:00
Sean Christopherson
17ed14eba2 KVM: arm64: Drop perf.c and fold its tiny bits of code into arm.c
Call KVM's (un)register perf callbacks helpers directly from arm.c and
delete perf.c

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20211111020738.2512932-17-seanjc@google.com
2021-11-17 14:49:11 +01:00
Sean Christopherson
e1bfc24577 KVM: Move x86's perf guest info callbacks to generic KVM
Move x86's perf guest callbacks into common KVM, as they are semantically
identical to arm64's callbacks (the only other such KVM callbacks).
arm64 will convert to the common versions in a future patch.

Implement the necessary arm64 arch hooks now to avoid having to provide
stubs or a temporary #define (from x86) to avoid arm64 compilation errors
when CONFIG_GUEST_PERF_EVENTS=y.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211111020738.2512932-13-seanjc@google.com
2021-11-17 14:49:10 +01:00
Paolo Bonzini
84886c262e KVM/arm64 fixes for 5.16, take #1
- Fix the host S2 finalization by solely iterating over the memblocks
   instead of the whole IPA space
 
 - Tighten the return value of kvm_vcpu_preferred_target() now that
   32bit support is long gone
 
 - Make sure the extraction of ESR_ELx.EC is limited to the architected
   bits
 
 - Comment fixups
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Merge tag 'kvmarm-fixes-5.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master

KVM/arm64 fixes for 5.16, take #1

- Fix the host S2 finalization by solely iterating over the memblocks
  instead of the whole IPA space

- Tighten the return value of kvm_vcpu_preferred_target() now that
  32bit support is long gone

- Make sure the extraction of ESR_ELx.EC is limited to the architected
  bits

- Comment fixups
2021-11-12 16:01:55 -05:00
YueHaibing
08e873cb70 KVM: arm64: Change the return type of kvm_vcpu_preferred_target()
kvm_vcpu_preferred_target() always return 0 because kvm_target_cpu()
never returns a negative error code.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211105011500.16280-1-yuehaibing@huawei.com
2021-11-08 10:48:47 +00:00
Paolo Bonzini
4e33868433 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
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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
Marc Zyngier
be08c3cf3c Merge branch kvm-arm64/pkvm/fixed-features into kvmarm-master/next
* kvm-arm64/pkvm/fixed-features: (22 commits)
  : .
  : Add the pKVM fixed feature that allows a bunch of exceptions
  : to either be forbidden or be easily handled at EL2.
  : .
  KVM: arm64: pkvm: Give priority to standard traps over pvm handling
  KVM: arm64: pkvm: Pass vpcu instead of kvm to kvm_get_exit_handler_array()
  KVM: arm64: pkvm: Move kvm_handle_pvm_restricted around
  KVM: arm64: pkvm: Consolidate include files
  KVM: arm64: pkvm: Preserve pending SError on exit from AArch32
  KVM: arm64: pkvm: Handle GICv3 traps as required
  KVM: arm64: pkvm: Drop sysregs that should never be routed to the host
  KVM: arm64: pkvm: Drop AArch32-specific registers
  KVM: arm64: pkvm: Make the ERR/ERX*_EL1 registers RAZ/WI
  KVM: arm64: pkvm: Use a single function to expose all id-regs
  KVM: arm64: Fix early exit ptrauth handling
  KVM: arm64: Handle protected guests at 32 bits
  KVM: arm64: Trap access to pVM restricted features
  KVM: arm64: Move sanitized copies of CPU features
  KVM: arm64: Initialize trap registers for protected VMs
  KVM: arm64: Add handlers for protected VM System Registers
  KVM: arm64: Simplify masking out MTE in feature id reg
  KVM: arm64: Add missing field descriptor for MDCR_EL2
  KVM: arm64: Pass struct kvm to per-EC handlers
  KVM: arm64: Move early handlers to per-EC handlers
  ...

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-10-18 17:20:50 +01:00
Marc Zyngier
5f8b2591de Merge branch kvm-arm64/memory-accounting into kvmarm-master/next
* kvm-arm64/memory-accounting:
  : .
  : Sprinkle a bunch of GFP_KERNEL_ACCOUNT all over the code base
  : to better track memory allocation made on behalf of a VM.
  : .
  KVM: arm64: Add memcg accounting to KVM allocations
  KVM: arm64: vgic: Add memcg accounting to vgic allocations

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-10-17 11:29:36 +01:00
Jia He
115bae923a KVM: arm64: Add memcg accounting to KVM allocations
Inspired by commit 254272ce65 ("kvm: x86: Add memcg accounting to KVM
allocations"), it would be better to make arm64 KVM consistent with
common kvm codes.

The memory allocations of VM scope should be charged into VM process
cgroup, hence change GFP_KERNEL to GFP_KERNEL_ACCOUNT.

There remain a few cases since these allocations are global, not in VM
scope.

Signed-off-by: Jia He <justin.he@arm.com>
Reviewed-by: Oliver Upton <oupton@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210907123112.10232-3-justin.he@arm.com
2021-10-17 11:25:55 +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
Marc Zyngier
a049cf7e63 Merge branch kvm-arm64/misc-5.16 into kvmarm-master/next
* kvm-arm64/misc-5.16:
  : .
  : - Allow KVM to be disabled from the command-line
  : - Clean up CONFIG_KVM vs CONFIG_HAVE_KVM
  : .
  KVM: arm64: Depend on HAVE_KVM instead of OF
  KVM: arm64: Unconditionally include generic KVM's Kconfig
  KVM: arm64: Allow KVM to be disabled from the command line

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-10-11 10:14:38 +01:00