Contrary to what df652bcf11 ("KVM: arm64: vgic-v3: Work around GICv3
locally generated SErrors") was asserting, there is at least one other
system out there (Cavium ThunderX2) implementing SEIS, and not in
an obviously broken way.
So instead of imposing the M1 workaround on an innocent bystander,
let's limit it to the two known broken Apple implementations.
Fixes: df652bcf11 ("KVM: arm64: vgic-v3: Work around GICv3 locally generated SErrors")
Reported-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220122103912.795026-1-maz@kernel.org
CMOs issued from EL2 cannot directly use the kernel helpers,
as EL2 doesn't have a mapping of the guest pages. Oops.
Instead, use the mm_ops indirection to use helpers that will
perform a mapping at EL2 and allow the CMO to be effective.
Fixes: 25aa28691b ("KVM: arm64: Move guest CMOs to the fault handlers")
Reviewed-by: Quentin Perret <qperret@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220114125038.1336965-1-maz@kernel.org
* kvm-arm64/selftest/irq-injection:
: .
: New tests from Ricardo Koller:
: "This series adds a new test, aarch64/vgic-irq, that validates the injection of
: different types of IRQs from userspace using various methods and configurations"
: .
KVM: selftests: aarch64: Add test for restoring active IRQs
KVM: selftests: aarch64: Add ISPENDR write tests in vgic_irq
KVM: selftests: aarch64: Add tests for IRQFD in vgic_irq
KVM: selftests: Add IRQ GSI routing library functions
KVM: selftests: aarch64: Add test_inject_fail to vgic_irq
KVM: selftests: aarch64: Add tests for LEVEL_INFO in vgic_irq
KVM: selftests: aarch64: Level-sensitive interrupts tests in vgic_irq
KVM: selftests: aarch64: Add preemption tests in vgic_irq
KVM: selftests: aarch64: Cmdline arg to set EOI mode in vgic_irq
KVM: selftests: aarch64: Cmdline arg to set number of IRQs in vgic_irq test
KVM: selftests: aarch64: Abstract the injection functions in vgic_irq
KVM: selftests: aarch64: Add vgic_irq to test userspace IRQ injection
KVM: selftests: aarch64: Add vGIC library functions to deal with vIRQ state
KVM: selftests: Add kvm_irq_line library function
KVM: selftests: aarch64: Add GICv3 register accessor library functions
KVM: selftests: aarch64: Add function for accessing GICv3 dist and redist registers
KVM: selftests: aarch64: Move gic_v3.h to shared headers
Signed-off-by: Marc Zyngier <maz@kernel.org>
* kvm-arm64/selftest/ipa:
: .
: Expand the KVM/arm64 selftest infrastructure to discover
: supported page sizes at runtime, support 16kB pages, and
: find out about the original M1 stupidly small IPA space.
: .
KVM: selftests: arm64: Add support for various modes with 16kB page size
KVM: selftests: arm64: Add support for VM_MODE_P36V48_{4K,64K}
KVM: selftests: arm64: Rework TCR_EL1 configuration
KVM: selftests: arm64: Check for supported page sizes
KVM: selftests: arm64: Introduce a variable default IPA size
KVM: selftests: arm64: Initialise default guest mode at test startup time
Signed-off-by: Marc Zyngier <maz@kernel.org>
The get-reg-list test ignores the Pointer Authentication features,
which is a shame now that we have relatively common HW with this feature.
Define two new configurations (with and without PMU) that exercise the
KVM capabilities.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Link: https://lore.kernel.org/r/20211228121414.1013250-1-maz@kernel.org
Add a cmdline arg for using level-sensitive interrupts (vs the default
edge-triggered). Then move the handler into a generic handler function
that takes the type of interrupt (level vs. edge) as an arg. When
handling line-sensitive interrupts it sets the line to low after
acknowledging the IRQ.
Signed-off-by: Ricardo Koller <ricarkol@google.com>
Acked-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211109023906.1091208-12-ricarkol@google.com
Build an abstraction around the injection functions, so the preparation
and checking around the actual injection can be shared between tests.
All functions are stored as pointers in arrays of kvm_inject_desc's
which include the pointer and what kind of interrupts they can inject.
Signed-off-by: Ricardo Koller <ricarkol@google.com>
Acked-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211109023906.1091208-8-ricarkol@google.com
The 16kB page size is not a popular choice, due to only a few CPUs
actually implementing support for it. However, it can lead to some
interesting performance improvements given the right uarch choices.
Add support for this page size for various PA/VA combinations.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Link: https://lore.kernel.org/r/20211227124809.1335409-7-maz@kernel.org
Some of the arm64 systems out there have an IPA space that is
positively tiny. Nonetheless, they make great KVM hosts.
Add support for 36bit IPA support with 4kB pages, which makes
some of the fruity machines happy. Whilst we're at it, add support
for 64kB pages as well, though these boxes have no support for it.
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211227124809.1335409-6-maz@kernel.org
The current way we initialise TCR_EL1 is a bit cumbersome, as
we mix setting TG0 and IPS in the same swtch statement.
Split it into two statements (one for the base granule size, and
another for the IPA size), allowing new modes to be added in a
more elegant way.
No functional change intended.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Link: https://lore.kernel.org/r/20211227124809.1335409-5-maz@kernel.org
Just as arm64 implemenations don't necessary support all IPA
ranges, they don't all support the same page sizes either. Fun.
Create a dummy VM to snapshot the page sizes supported by the
host, and filter the supported modes.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Link: https://lore.kernel.org/r/20211227124809.1335409-4-maz@kernel.org
Contrary to popular belief, there is no such thing as a default
IPA size on arm64. Anything goes, and implementations are the
usual Wild West.
The selftest infrastructure default to 40bit IPA, which obviously
doesn't work for some systems out there.
Turn VM_MODE_DEFAULT from a constant into a variable, and let
guest_modes_append_default() populate it, depending on what
the HW can do. In order to preserve the current behaviour, we
still pick 40bits IPA as the default if it is available, and
the largest supported IPA space otherwise.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Link: https://lore.kernel.org/r/20211227124809.1335409-3-maz@kernel.org
Ganapatrao reported that the kvm_pgtable->mmu pointer is more or
less hardcoded to the main S2 mmu structure, while the nested
code needs it to point to other instances (as we have one instance
per nested context).
Rework the initialisation of the kvm_pgtable structure so that
this assumtion doesn't hold true anymore. This requires some
minor changes to the order in which things are initialised
(the mmu->arch pointer being the critical one).
Reported-by: Ganapatrao Kulkarni <gankulkarni@os.amperecomputing.com>
Reviewed-by: Ganapatrao Kulkarni <gankulkarni@os.amperecomputing.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211129200150.351436-5-maz@kernel.org
* 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>
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
Tearing down a previously shared memory region results in the borrower
losing access to the underlying pages and returning them to the "owned"
state in the owner.
Implement a do_unshare() helper, along the same lines as do_share(), to
provide this functionality for the host-to-hyp case.
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/20211215161232.1480836-13-qperret@google.com
__pkvm_host_share_hyp() shares memory between the host and the
hypervisor so implement it as an invocation of the new do_share()
mechanism.
Note that double-sharing is no longer permitted (as this allows us to
reduce the number of page-table walks significantly), but is thankfully
no longer relied upon by the host.
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/20211215161232.1480836-12-qperret@google.com
By default, protected KVM isolates memory pages so that they are
accessible only to their owner: be it the host kernel, the hypervisor
at EL2 or (in future) the guest. Establishing shared-memory regions
between these components therefore involves a transition for each page
so that the owner can share memory with a borrower under a certain set
of permissions.
Introduce a do_share() helper for safely sharing a memory region between
two components. Currently, only host-to-hyp sharing is implemented, but
the code is easily extended to handle other combinations and the
permission checks for each component are reusable.
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/20211215161232.1480836-11-qperret@google.com
In preparation for adding additional locked sections for manipulating
page-tables at EL2, introduce some simple wrappers around the host and
hypervisor locks so that it's a bit easier to read and bit more difficult
to take the wrong lock (or even take them in the wrong order).
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/20211215161232.1480836-10-qperret@google.com
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
In order to simplify the page tracking infrastructure at EL2 in nVHE
protected mode, move the responsibility of refcounting pages that are
shared multiple times on the host. In order to do so, let's create a
red-black tree tracking all the PFNs that have been shared, along with
a refcount.
Acked-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/20211215161232.1480836-8-qperret@google.com
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
In nVHE protected mode, the EL2 code uses a temporary allocator during
boot while re-creating its stage-1 page-table. Unfortunately, the
hyp_vmmemap is not ready to use at this stage, so refcounting pages
is not possible. That is not currently a problem because hyp stage-1
mappings are never removed, which implies refcounting of page-table
pages is unnecessary.
In preparation for allowing hypervisor stage-1 mappings to be removed,
provide stub implementations for {get,put}_page() in the early allocator.
Acked-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/20211215161232.1480836-2-qperret@google.com
