* kvm-arm64/misc-6.1:
: .
: Misc KVM/arm64 fixes and improvement for v6.1
:
: - Simplify the affinity check when moving a GICv3 collection
:
: - Tone down the shouting when kvm-arm.mode=protected is passed
: to a guest
:
: - Fix various comments
:
: - Advertise the new kvmarm@lists.linux.dev and deprecate the
: old Columbia list
: .
KVM: arm64: Advertise new kvmarm mailing list
KVM: arm64: Fix comment typo in nvhe/switch.c
KVM: selftests: Update top-of-file comment in psci_test
KVM: arm64: Ignore kvm-arm.mode if !is_hyp_mode_available()
KVM: arm64: vgic: Remove duplicate check in update_affinity_collection()
Signed-off-by: Marc Zyngier <maz@kernel.org>
* kvm-arm64/dirty-log-ordered:
: .
: Retrofit some ordering into the existing API dirty-ring by:
:
: - relying on acquire/release semantics which are the default on x86,
: but need to be explicit on arm64
:
: - adding a new capability that indicate which flavor is supported, either
: with explicit ordering (arm64) or both implicit and explicit (x86),
: as suggested by Paolo at KVM Forum
:
: - documenting the requirements for this new capability on weakly ordered
: architectures
:
: - updating the selftests to do the right thing
: .
KVM: selftests: dirty-log: Use KVM_CAP_DIRTY_LOG_RING_ACQ_REL if available
KVM: selftests: dirty-log: Upgrade flag accesses to acquire/release semantics
KVM: Document weakly ordered architecture requirements for dirty ring
KVM: x86: Select CONFIG_HAVE_KVM_DIRTY_RING_ACQ_REL
KVM: Add KVM_CAP_DIRTY_LOG_RING_ACQ_REL capability and config option
KVM: Use acquire/release semantics when accessing dirty ring GFN state
Signed-off-by: Marc Zyngier <maz@kernel.org>
As announced on the kvmarm list, we're moving the mailing list over
to kvmarm@lists.linux.dev:
<quote>
As you probably all know, the kvmarm mailing has been hosted on
Columbia's machines for as long as the project existed (over 13
years). After all this time, the university has decided to retire the
list infrastructure and asked us to find a new hosting.
A new mailing list has been created on lists.linux.dev[1], and I'm
kindly asking everyone interested in following the KVM/arm64
developments to start subscribing to it (and start posting your
patches there). I hope that people will move over to it quickly enough
that we can soon give Columbia the green light to turn their systems
off.
Note that the new list will only get archived automatically once we
fully switch over, but I'll make sure we fill any gap and not lose any
message. In the meantime, please Cc both lists.
[...]
[1] https://subspace.kernel.org/lists.linux.dev.html
</quote>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221001091245.3900668-1-maz@kernel.org
In order to differenciate between architectures that require no extra
synchronisation when accessing the dirty ring and those who do,
add a new capability (KVM_CAP_DIRTY_LOG_RING_ACQ_REL) that identify
the latter sort. TSO architectures can obviously advertise both, while
relaxed architectures must only advertise the ACQ_REL version.
This requires some configuration symbol rejigging, with HAVE_KVM_DIRTY_RING
being only indirectly selected by two top-level config symbols:
- HAVE_KVM_DIRTY_RING_TSO for strongly ordered architectures (x86)
- HAVE_KVM_DIRTY_RING_ACQ_REL for weakly ordered architectures (arm64)
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20220926145120.27974-3-maz@kernel.org
The current implementation of the dirty ring has an implicit requirement
that stores to the dirty ring from userspace must be:
- be ordered with one another
- visible from another CPU executing a ring reset
While these implicit requirements work well for x86 (and any other
TSO-like architecture), they do not work for more relaxed architectures
such as arm64 where stores to different addresses can be freely
reordered, and loads from these addresses not observing writes from
another CPU unless the required barriers (or acquire/release semantics)
are used.
In order to start fixing this, upgrade the ring reset accesses:
- the kvm_dirty_gfn_harvested() helper now uses acquire semantics
so it is ordered after all previous writes, including that from
userspace
- the kvm_dirty_gfn_set_invalid() helper now uses release semantics
so that the next_slot and next_offset reads don't drift past
the entry invalidation
This is only a partial fix as the userspace side also need upgrading.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20220926145120.27974-2-maz@kernel.org
Fix the comment to accurately describe the test and recently added
SYSTEM_SUSPEND test case.
What was once psci_cpu_on_test was renamed and extended to squeeze in a
test case for PSCI SYSTEM_SUSPEND. Nonetheless, the author of those
changes (whoever they may be...) failed to update the file comment to
reflect what had changed.
Reported-by: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220819162100.213854-1-oliver.upton@linux.dev
Ignore kvm-arm.mode if !is_hyp_mode_available(). Specifically, we want
to avoid switching kvm_mode to KVM_MODE_PROTECTED if hypervisor mode is
not available. This prevents "Protected KVM" cpu capability being
reported when Linux is booting in EL1 and would not have KVM enabled.
Reasonably though, we should warn if the command line is requesting a
KVM mode at all if KVM isn't actually available. Allow
"kvm-arm.mode=none" to skip the warning since this would disable KVM
anyway.
Signed-off-by: Elliot Berman <quic_eberman@quicinc.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220920190658.2880184-1-quic_eberman@quicinc.com
The 'coll' parameter to update_affinity_collection() is never NULL,
so comparing it with 'ite->collection' is enough to cover both
the NULL case and the "another collection" case.
Remove the duplicate check in update_affinity_collection().
Signed-off-by: Gavin Shan <gshan@redhat.com>
[maz: repainted commit message]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220923065447.323445-1-gshan@redhat.com
* kvm-arm64/single-step-async-exception:
: .
: Single-step fixes from Reiji Watanabe:
:
: "This series fixes two bugs of single-step execution enabled by
: userspace, and add a test case for KVM_GUESTDBG_SINGLESTEP to
: the debug-exception test to verify the single-step behavior."
: .
KVM: arm64: selftests: Add a test case for KVM_GUESTDBG_SINGLESTEP
KVM: arm64: selftests: Refactor debug-exceptions to make it amenable to new test cases
KVM: arm64: Clear PSTATE.SS when the Software Step state was Active-pending
KVM: arm64: Preserve PSTATE.SS for the guest while single-step is enabled
Signed-off-by: Marc Zyngier <maz@kernel.org>
Add a test case for KVM_GUESTDBG_SINGLESTEP to the debug-exceptions test.
The test enables single-step execution from userspace, and check if the
exit to userspace occurs for each instruction that is stepped.
Set the default number of the test iterations to a number of iterations
sufficient to always reproduce the problem that the previous patch fixes
on an Ampere Altra machine.
Signed-off-by: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220917010600.532642-5-reijiw@google.com
While userspace enables single-step, if the Software Step state at the
last guest exit was "Active-pending", clear PSTATE.SS on guest entry
to restore the state.
Currently, KVM sets PSTATE.SS to 1 on every guest entry while userspace
enables single-step for the vCPU (with KVM_GUESTDBG_SINGLESTEP).
It means KVM always makes the vCPU's Software Step state
"Active-not-pending" on the guest entry, which lets the VCPU perform
single-step (then Software Step exception is taken). This could cause
extra single-step (without returning to userspace) if the Software Step
state at the last guest exit was "Active-pending" (i.e. the last
exit was triggered by an asynchronous exception after the single-step
is performed, but before the Software Step exception is taken.
See "Figure D2-3 Software step state machine" and "D2.12.7 Behavior
in the active-pending state" in ARM DDI 0487I.a for more info about
this behavior).
Fix this by clearing PSTATE.SS on guest entry if the Software Step state
at the last exit was "Active-pending" so that KVM restore the state (and
the exception is taken before further single-step is performed).
Fixes: 337b99bf7e ("KVM: arm64: guest debug, add support for single-step")
Signed-off-by: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220917010600.532642-3-reijiw@google.com
Preserve the PSTATE.SS value for the guest while userspace enables
single-step (i.e. while KVM manipulates the PSTATE.SS) for the vCPU.
Currently, while userspace enables single-step for the vCPU
(with KVM_GUESTDBG_SINGLESTEP), KVM sets PSTATE.SS to 1 on every
guest entry, not saving its original value.
When userspace disables single-step, KVM doesn't restore the original
value for the subsequent guest entry (use the current value instead).
Exception return instructions copy PSTATE.SS from SPSR_ELx.SS
only in certain cases when single-step is enabled (and set it to 0
in other cases). So, the value matters only when the guest enables
single-step (and when the guest's Software step state isn't affected
by single-step enabled by userspace, practically), though.
Fix this by preserving the original PSTATE.SS value while userspace
enables single-step, and restoring the value once it is disabled.
This fix modifies the behavior of GET_ONE_REG/SET_ONE_REG for the
PSTATE.SS while single-step is enabled by userspace.
Presently, GET_ONE_REG/SET_ONE_REG gets/sets the current PSTATE.SS
value, which KVM will override on the next guest entry (i.e. the
value userspace gets/sets is not used for the next guest entry).
With this patch, GET_ONE_REG/SET_ONE_REG will get/set the guest's
preserved value, which KVM will preserve and try to restore after
single-step is disabled.
Fixes: 337b99bf7e ("KVM: arm64: guest debug, add support for single-step")
Signed-off-by: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220917010600.532642-2-reijiw@google.com
Merge arm64/for-next/sysreg in order to avoid upstream conflicts
due to the never ending sysreg repainting...
Signed-off-by: Marc Zyngier <maz@kernel.org>
Currently the kernel refers to the versions of the PMU and SPE features by
the version of the architecture where those features were updated but the
ARM refers to them using the FEAT_ names for the features. To improve
consistency and help with updating for newer features and since v9 will
make our current naming scheme a bit more confusing update the macros
identfying features to use the FEAT_ based scheme.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220910163354.860255-4-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Normally we include the full register name in the defines for fields within
registers but this has not been followed for ID registers. In preparation
for automatic generation of defines add the _EL1s into the defines for
ID_AA64DFR0_EL1 to follow the convention. No functional changes.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220910163354.860255-3-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The naming scheme the architecture uses for the fields in ID_AA64DFR0_EL1
does not align well with kernel conventions, using as it does a lot of
MixedCase in various arrangements. In preparation for automatically
generating the defines for this register rename the defines used to match
what is in the architecture.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220910163354.860255-2-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kvm-arm64/aarch32-raz-idregs:
: .
: Rework AArch32 ID registers exposed by KVM on AArch64-only
: systems by treating them as RAZ/WI instead as UNKOWN as
: architected, which allows them to be trivially migrated
: between different systems.
:
: Patches courtesy of Oliver Upton.
: .
KVM: selftests: Add test for AArch32 ID registers
KVM: arm64: Treat 32bit ID registers as RAZ/WI on 64bit-only system
KVM: arm64: Add a visibility bit to ignore user writes
KVM: arm64: Spin off helper for calling visibility hook
KVM: arm64: Drop raz parameter from read_id_reg()
KVM: arm64: Remove internal accessor helpers for id regs
KVM: arm64: Use visibility hook to treat ID regs as RAZ
Signed-off-by: Marc Zyngier <maz@kernel.org>
One of the oddities of the architecture is that the AArch64 views of the
AArch32 ID registers are UNKNOWN if AArch32 isn't implemented at any EL.
Nonetheless, KVM exposes these registers to userspace for the sake of
save/restore. It is possible that the UNKNOWN value could differ between
systems, leading to a rejected write from userspace.
Avoid the issue altogether by handling the AArch32 ID registers as
RAZ/WI when on an AArch64-only system.
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220913094441.3957645-7-oliver.upton@linux.dev
Automatically generate most of the defines for ID_AA64MMFR0_EL1 mostly as
per DDI0487H.a. Due to the large amount of MixedCase in this register which
isn't really consistent with either the kernel style or the majority of the
architecture the use of upper case is preserved. We also leave in place a
number of min/max/default value definitions which don't flow from the
architecture definitions.
No functional changes.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-22-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The naming for fractional versions fields in ID_AA64PFR1_EL1 does not align
with that in the architecture, lacking underscores and using upper case
where the architecture uses lower case. In preparation for automatic
generation of defines bring the code in sync with the architecture, no
functional change.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20220905225425.1871461-18-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
