* kvm-arm64/nv-pmu:
: Support for vEL2 PMU controls
:
: Align the vEL2 PMU support with the current state of non-nested KVM,
: including:
:
: - Trap routing, with the annoying complication of EL2 traps that apply
: in Host EL0
:
: - PMU emulation, using the correct configuration bits depending on
: whether a counter falls in the hypervisor or guest range of PMCs
:
: - Perf event swizzling across nested boundaries, as the event filtering
: needs to be remapped to cope with vEL2
KVM: arm64: nv: Reprogram PMU events affected by nested transition
KVM: arm64: nv: Apply EL2 event filtering when in hyp context
KVM: arm64: nv: Honor MDCR_EL2.HLP
KVM: arm64: nv: Honor MDCR_EL2.HPME
KVM: arm64: Add helpers to determine if PMC counts at a given EL
KVM: arm64: nv: Adjust range of accessible PMCs according to HPMN
KVM: arm64: Rename kvm_pmu_valid_counter_mask()
KVM: arm64: nv: Advertise support for FEAT_HPMN0
KVM: arm64: nv: Describe trap behaviour of MDCR_EL2.HPMN
KVM: arm64: nv: Honor MDCR_EL2.{TPM, TPMCR} in Host EL0
KVM: arm64: nv: Reinject traps that take effect in Host EL0
KVM: arm64: nv: Rename BEHAVE_FORWARD_ANY
KVM: arm64: nv: Allow coarse-grained trap combos to use complex traps
KVM: arm64: Describe RES0/RES1 bits of MDCR_EL2
arm64: sysreg: Add new definitions for ID_AA64DFR0_EL1
arm64: sysreg: Migrate MDCR_EL2 definition to table
arm64: sysreg: Describe ID_AA64DFR2_EL1 fields
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Start reprogramming PMU events at nested boundaries now that everything
is in place to handle the EL2 event filter. Only repaint events where
the filter differs between EL1 and EL2 as a slight optimization.
PMU now 'works' for nested VMs, albeit slow.
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20241025182559.3364829-1-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
MDCR_EL2.HPMN splits the PMU event counters into two ranges: the first
range is accessible from all ELs, and the second range is accessible
only to EL2/3. Supposing the guest hypervisor allows direct access to
the PMU counters from the L2, KVM needs to locally handle those
accesses.
Add a new complex trap configuration for HPMN that checks if the counter
index is accessible to the current context. As written, the architecture
suggests HPMN only causes PMEVCNTR<n>_EL0 to trap, though intuition (and
the pseudocode) suggest that the trap applies to PMEVTYPER<n>_EL0 as
well.
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20241025182354.3364124-11-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
TPM and TPMCR trap bits also affect Host EL0. How fun.
Mark these two trap bits as such and take advantage of the new
infrastructure for dealing w/ EL0 traps.
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20241025182354.3364124-10-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Wire up the other end of traps that affect host EL0 by actually
injecting them into the guest hypervisor. Skip over FGT entirely, as a
cursory glance suggests no FGT is effective in host EL0.
Note that kvm_inject_nested() is already equipped for handling
exceptions while the VM is already in a host context.
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20241025182354.3364124-9-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
BEHAVE_FORWARD_ANY is slightly ambiguous, especially since we're about
to cram some more information into the enum. Rephrase it.
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20241025182354.3364124-8-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
KVM uses a sanity-check to avoid infinite recursion in trap combinations
that could potentially depend on itself. Narrow the scope of this sanity
check to the exact CGT IDs that correspond w/ trap combos, opening the
door to using 'complex' traps as part of a combination.
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20241025182354.3364124-7-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
All the El0/EL1 S1PIE/S1POE system register are caught by the HCR_EL2
TVM and TRVM bits. Reflect this in the coarse grained trap table.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20241023145345.1613824-30-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
It took me some time to realise it, but CPTR_EL2.E0POE does not
apply to a guest, only to EL0 when InHost(). And when InHost(),
CPCR_EL2 is mapped to CPACR_EL1, maning that the E0POE bit naturally
takes effect without any trap.
To sum it up, this trap bit is better left ignored, we will never
have to hanedle it.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20241023145345.1613824-29-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
* kvm-arm64/nv-at-pan:
: .
: Add NV support for the AT family of instructions, which mostly results
: in adding a page table walker that deals with most of the complexity
: of the architecture.
:
: From the cover letter:
:
: "Another task that a hypervisor supporting NV on arm64 has to deal with
: is to emulate the AT instruction, because we multiplex all the S1
: translations on a single set of registers, and the guest S2 is never
: truly resident on the CPU.
:
: So given that we lie about page tables, we also have to lie about
: translation instructions, hence the emulation. Things are made
: complicated by the fact that guest S1 page tables can be swapped out,
: and that our shadow S2 is likely to be incomplete. So while using AT
: to emulate AT is tempting (and useful), it is not going to always
: work, and we thus need a fallback in the shape of a SW S1 walker."
: .
KVM: arm64: nv: Add support for FEAT_ATS1A
KVM: arm64: nv: Plumb handling of AT S1* traps from EL2
KVM: arm64: nv: Make AT+PAN instructions aware of FEAT_PAN3
KVM: arm64: nv: Sanitise SCTLR_EL1.EPAN according to VM configuration
KVM: arm64: nv: Add SW walker for AT S1 emulation
KVM: arm64: nv: Make ps_to_output_size() generally available
KVM: arm64: nv: Add emulation of AT S12E{0,1}{R,W}
KVM: arm64: nv: Add basic emulation of AT S1E2{R,W}
KVM: arm64: nv: Add basic emulation of AT S1E1{R,W}P
KVM: arm64: nv: Add basic emulation of AT S1E{0,1}{R,W}
KVM: arm64: nv: Honor absence of FEAT_PAN2
KVM: arm64: nv: Turn upper_attr for S2 walk into the full descriptor
KVM: arm64: nv: Enforce S2 alignment when contiguous bit is set
arm64: Add ESR_ELx_FSC_ADDRSZ_L() helper
arm64: Add system register encoding for PSTATE.PAN
arm64: Add PAR_EL1 field description
arm64: Add missing APTable and TCR_ELx.HPD masks
KVM: arm64: Make kvm_at() take an OP_AT_*
Signed-off-by: Marc Zyngier <maz@kernel.org>
# Conflicts:
# arch/arm64/kvm/nested.c
* kvm-arm64/vgic-sre-traps:
: .
: Fix the multiple of cases where KVM/arm64 doesn't correctly
: handle the guest trying to use a GICv3 that isn't advertised.
:
: From the cover letter:
:
: "It recently appeared that, when running on a GICv3-equipped platform
: (which is what non-ancient arm64 HW has), *not* configuring a GICv3
: for the guest could result in less than desirable outcomes.
:
: We have multiple issues to fix:
:
: - for registers that *always* trap (the SGI registers) or that *may*
: trap (the SRE register), we need to check whether a GICv3 has been
: instantiated before acting upon the trap.
:
: - for registers that only conditionally trap, we must actively trap
: them even in the absence of a GICv3 being instantiated, and handle
: those traps accordingly.
:
: - finally, ID registers must reflect the absence of a GICv3, so that
: we are consistent.
:
: This series goes through all these requirements. The main complexity
: here is to apply a GICv3 configuration on the host in the absence of a
: GICv3 in the guest. This is pretty hackish, but I don't have a much
: better solution so far.
:
: As part of making wider use of of the trap bits, we fully define the
: trap routing as per the architecture, something that we eventually
: need for NV anyway."
: .
KVM: arm64: selftests: Cope with lack of GICv3 in set_id_regs
KVM: arm64: Add selftest checking how the absence of GICv3 is handled
KVM: arm64: Unify UNDEF injection helpers
KVM: arm64: Make most GICv3 accesses UNDEF if they trap
KVM: arm64: Honor guest requested traps in GICv3 emulation
KVM: arm64: Add trap routing information for ICH_HCR_EL2
KVM: arm64: Add ICH_HCR_EL2 to the vcpu state
KVM: arm64: Zero ID_AA64PFR0_EL1.GIC when no GICv3 is presented to the guest
KVM: arm64: Add helper for last ditch idreg adjustments
KVM: arm64: Force GICv3 trap activation when no irqchip is configured on VHE
KVM: arm64: Force SRE traps when SRE access is not enabled
KVM: arm64: Move GICv3 trap configuration to kvm_calculate_traps()
Signed-off-by: Marc Zyngier <maz@kernel.org>
Handling FEAT_ATS1A (which provides the AT S1E{1,2}A instructions)
is pretty easy, as it is just the usual AT without the permission
check.
This basically amounts to plumbing the instructions in the various
dispatch tables, and handling FEAT_ATS1A being disabled in the
ID registers.
Signed-off-by: Marc Zyngier <maz@kernel.org>
The usual song and dance. Anything that is a trap, any register
it traps. Note that we don't handle the registers added by
FEAT_NMI for now.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240827152517.3909653-8-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
HCRX_EL2.EnFPM controls the trapping of FPMR (as well as the validity
of any FP8 instruction, but we don't really care about this last part).
Describe the trap bit so that the exception can be reinjected in a
NV guest.
Reviewed-by: Mark Brown <broonie@kernel.org>
Tested-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20240820131802.3547589-6-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
* kvm-arm64/nv-tcr2:
: Fixes to the handling of TCR_EL1, courtesy of Marc Zyngier
:
: Series addresses a couple gaps that are present in KVM (from cover
: letter):
:
: - VM configuration: HCRX_EL2.TCR2En is forced to 1, and we blindly
: save/restore stuff.
:
: - trap bit description and routing: none, obviously, since we make a
: point in not trapping.
KVM: arm64: Honor trap routing for TCR2_EL1
KVM: arm64: Make PIR{,E0}_EL1 save/restore conditional on FEAT_TCRX
KVM: arm64: Make TCR2_EL1 save/restore dependent on the VM features
KVM: arm64: Get rid of HCRX_GUEST_FLAGS
KVM: arm64: Correctly honor the presence of FEAT_TCRX
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
TCR2_EL1 handling is missing the handling of its trap configuration:
- HCRX_EL2.TCR2En must be handled in conjunction with HCR_EL2.{TVM,TRVM}
- HFG{R,W}TR_EL2.TCR_EL1 does apply to TCR2_EL1 as well
Without these two controls being implemented, it is impossible to
correctly route TCR2_EL1 traps.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240625130042.259175-7-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Add trap description for CPTR_EL2.{TCPAC,TAM,E0POE,TTA}.
TTA is a bit annoying as it changes location depending on E2H.
This forces us to add yet another "complex" trap condition.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240620164653.1130714-14-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
ERETAx can fail in multiple ways:
(1) ELR_EL2 points lalaland
(2) we get a PAC failure
(3) SPSR_EL2 has the wrong mode
(1) is easy, as we just let the CPU do its thing and deliver an
Instruction Abort. However, (2) and (3) are interesting, because
the PAC failure priority is way below that of the Illegal Execution
State exception.
Which means that if we have detected a PAC failure (and that we have
FPACCOMBINE), we must be careful to give priority to the Illegal
Execution State exception, should one be pending.
Solving this involves hoisting the SPSR calculation earlier and
testing for the IL bit before injecting the FPAC exception.
In the extreme case of a ERETAx returning to an invalid mode *and*
failing its PAC check, we end up with an Instruction Abort (due
to the new PC being mangled by the failed Auth) *and* PSTATE.IL
being set. Which matches the requirements of the architecture.
Whilst we're at it, remove a stale comment that states the obvious
and only confuses the reader.
Fixes: 213b3d1ea1 ("KVM: arm64: nv: Handle ERETA[AB] instructions")
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240528100632.1831995-2-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
Now that we have some emulation in place for ERETA[AB], we can
plug it into the exception handling machinery.
As for a bare ERET, an "easy" ERETAx instruction is processed as
a fixup, while something that requires a translation regime
transition or an exception delivery is left to the slow path.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-14-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
A significant part of the FEAT_NV extension is to trap ERET
instructions so that the hypervisor gets a chance to switch
from a vEL2 L1 guest to an EL1 L2 guest.
But this also has the unfortunate consequence of trapping ERET
in unsuspecting circumstances, such as staying at vEL2 (interrupt
handling while being in the guest hypervisor), or returning to host
userspace in the case of a VHE guest.
Although we already make some effort to handle these ERET quicker
by not doing the put/load dance, it is still way too far down the
line for it to be efficient enough.
For these cases, it would ideal to ERET directly, no question asked.
Of course, we can't do that. But the next best thing is to do it as
early as possible, in fixup_guest_exit(), much as we would handle
FPSIMD exceptions.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-8-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
Honor the trap forwarding bits for both ERET and SMC, using a new
helper that checks for common conditions.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Co-developed-by: Jintack Lim <jintack.lim@linaro.org>
Signed-off-by: Jintack Lim <jintack.lim@linaro.org>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-7-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
In order to correctly honor our FGU bits, they must be converted
into a set of FGT bits. They get merged as part of the existing
FGT setting.
Similarly, the UNDEF injection phase takes place when handling
the trap.
This results in a bit of rework in the FGT macros in order to
help with the code generation, as burying per-CPU accesses in
macros results in a lot of expansion, not to mention the vcpu->kvm
access on nvhe (kern_hyp_va() is not optimisation-friendly).
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240214131827.2856277-19-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
In order to efficiently handle system register access being disabled,
and this resulting in an UNDEF exception being injected, we introduce
the (slightly dubious) concept of Fine-Grained UNDEF, modeled after
the architectural Fine-Grained Traps.
For each FGT group, we keep a 64 bit word that has the exact same
bit assignment as the corresponding FGT register, where a 1 indicates
that trapping this register should result in an UNDEF exception being
reinjected.
So far, nothing populates this information, nor sets the corresponding
trap bits.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240214131827.2856277-18-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
__check_nv_sr_forward() is not specific to NV anymore, and does
a lot more. Rename it to triage_sysreg_trap(), making it plain
that its role is to handle where an exception is to be handled.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240214131827.2856277-17-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Since we always start sysreg/sysinsn handling by searching the
xarray, use it as the source of the index in the correct sys_reg_desc
array.
This allows some cleanup, such as moving the handling of unknown
sysregs in a single location.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240214131827.2856277-16-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
In order to reduce the number of lookups that we have to perform
when handling a sysreg, register each AArch64 sysreg descriptor
with the global xarray. The index of the descriptor is stored
as a 10 bit field in the data word.
Subsequent patches will retrieve and use the stored index.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240214131827.2856277-15-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
In order to be able to store different values for member of an
encoding range, replace xa_store_range() calls with discrete
xa_store() calls and an encoding iterator.
We end-up using a bit more memory, but we gain some flexibility
that we will make use of shortly.
Take this opportunity to tidy up the error handling path.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Link: https://lore.kernel.org/r/20240214131827.2856277-11-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Negative trap bits are a massive pain. They are, on the surface,
indistinguishable from RES0 bits. Do you trap? or do you ignore?
Thankfully, we now have the right infrastructure to check for RES0
bits as long as the register is backed by VNCR, which is the case
for the FGT registers.
Use that information as a discriminant when handling a trap that
is potentially caused by a FGT.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240214131827.2856277-10-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
There is no reason to have separate FGT group identifiers for
the debug fine grain trapping. The sole requirement is to provide
the *names* so that the SR_FGF() macro can do its magic of picking
the correct bit definition.
So let's alias HDFGWTR_GROUP and HDFGRTR_GROUP.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240214131827.2856277-9-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Now that we have the infrastructure to enforce a sanitised register
value depending on the VM configuration, drop the helper that only
used the architectural RES0 value.
Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240214131827.2856277-8-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Add the encodings to fine grain trapping fields for HAFGRTR_EL2
and add the associated handling code in nested virt. Based on
DDI0601 2023-09. Add the missing field definitions as well,
both to generate the correct RES0 mask and to be able to toggle
their FGT bits.
Also add the code for handling FGT trapping, reading of the
register, to nested virt.
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231214100158.2305400-10-tabba@google.com
- Generalized infrastructure for 'writable' ID registers, effectively
allowing userspace to opt-out of certain vCPU features for its guest
- Optimization for vSGI injection, opportunistically compressing MPIDR
to vCPU mapping into a table
- Improvements to KVM's PMU emulation, allowing userspace to select
the number of PMCs available to a VM
- Guest support for memory operation instructions (FEAT_MOPS)
- Cleanups to handling feature flags in KVM_ARM_VCPU_INIT, squashing
bugs and getting rid of useless code
- Changes to the way the SMCCC filter is constructed, avoiding wasted
memory allocations when not in use
- Load the stage-2 MMU context at vcpu_load() for VHE systems, reducing
the overhead of errata mitigations
- Miscellaneous kernel and selftest fixes
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Merge tag 'kvmarm-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/arm64 updates for 6.7
- Generalized infrastructure for 'writable' ID registers, effectively
allowing userspace to opt-out of certain vCPU features for its guest
- Optimization for vSGI injection, opportunistically compressing MPIDR
to vCPU mapping into a table
- Improvements to KVM's PMU emulation, allowing userspace to select
the number of PMCs available to a VM
- Guest support for memory operation instructions (FEAT_MOPS)
- Cleanups to handling feature flags in KVM_ARM_VCPU_INIT, squashing
bugs and getting rid of useless code
- Changes to the way the SMCCC filter is constructed, avoiding wasted
memory allocations when not in use
- Load the stage-2 MMU context at vcpu_load() for VHE systems, reducing
the overhead of errata mitigations
- Miscellaneous kernel and selftest fixes
Implement a fine grained approach in the _EL2 sysreg range instead of
the current wide cast trap. This ensures that we don't mistakenly
inject the wrong exception into the guest.
[maz: commit message massaging, dropped secure and AArch32 registers
from the list]
Fixes: d0fc0a2519 ("KVM: arm64: nv: Add trap forwarding for HCR_EL2")
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Miguel Luis <miguel.luis@oracle.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231023095444.1587322-4-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
nPIR_EL1 and nPIREO_EL1 are part of the 'reverse polarity' set of bits, set
them so that we disable the traps for a guest. Unfortunately, these bits
are not yet described in the ARM ARM, but only live in the XML description.
Also add them to the NV FGT forwarding infrastructure.
Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Fixes: e930694e61 ("KVM: arm64: Restructure FGT register switching")
Cc: Oliver Upton <oliver.upton@linux.dev>
[maz: add entries to the NV FGT array, commit message update]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231012123459.2820835-2-joey.gouly@arm.com
Having carved a hole for SP_EL1, we are now missing the entries
for SPSR_EL2 and ELR_EL2. Add them back.
Reported-by: Miguel Luis <miguel.luis@oracle.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
HCRX_EL2 has an interesting effect on HFGITR_EL2, as it conditions
the traps of TLBI*nXS.
Expand the FGT support to add a new Fine Grained Filter that will
get checked when the instruction gets trapped, allowing the shadow
register to override the trap as needed.
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Jing Zhang <jingzhangos@google.com>
Link: https://lore.kernel.org/r/20230815183903.2735724-29-maz@kernel.org
... and finally, the Debug version of FGT, with its *enormous*
list of trapped registers.
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Jing Zhang <jingzhangos@google.com>
Link: https://lore.kernel.org/r/20230815183903.2735724-23-maz@kernel.org
Similarly, implement the trap forwarding for instructions affected
by HFGITR_EL2.
Note that the TLBI*nXS instructions should be affected by HCRX_EL2,
which will be dealt with down the line. Also, ERET* and SVC traps
are handled separately.
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Jing Zhang <jingzhangos@google.com>
Link: https://lore.kernel.org/r/20230815183903.2735724-22-maz@kernel.org
Implement the trap forwarding for traps described by HFGxTR_EL2,
reusing the Fine Grained Traps infrastructure previously implemented.
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Jing Zhang <jingzhangos@google.com>
Link: https://lore.kernel.org/r/20230815183903.2735724-21-maz@kernel.org
Fine Grained Traps are fun. Not.
Implement the fine grained trap forwarding, reusing the Coarse Grained
Traps infrastructure previously implemented.
Each sysreg/instruction inserted in the xarray gets a FGT group
(vaguely equivalent to a register number), a bit number in that register,
and a polarity.
It is then pretty easy to check the FGT state at handling time, just
like we do for the coarse version (it is just faster).
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Jing Zhang <jingzhangos@google.com>
Link: https://lore.kernel.org/r/20230815183903.2735724-20-maz@kernel.org
Describe the CNTHCTL_EL2 register, and associate it with all the sysregs
it allows to trap.
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Jing Zhang <jingzhangos@google.com>
Link: https://lore.kernel.org/r/20230815183903.2735724-19-maz@kernel.org
Describe the MDCR_EL2 register, and associate it with all the sysregs
it allows to trap.
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Jing Zhang <jingzhangos@google.com>
Link: https://lore.kernel.org/r/20230815183903.2735724-18-maz@kernel.org
Describe the HCR_EL2 register, and associate it with all the sysregs
it allows to trap.
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Jing Zhang <jingzhangos@google.com>
Link: https://lore.kernel.org/r/20230815183903.2735724-16-maz@kernel.org
A significant part of what a NV hypervisor needs to do is to decide
whether a trap from a L2+ guest has to be forwarded to a L1 guest
or handled locally. This is done by checking for the trap bits that
the guest hypervisor has set and acting accordingly, as described by
the architecture.
A previous approach was to sprinkle a bunch of checks in all the
system register accessors, but this is pretty error prone and doesn't
help getting an overview of what is happening.
Instead, implement a set of global tables that describe a trap bit,
combinations of trap bits, behaviours on trap, and what bits must
be evaluated on a system register trap.
Although this is painful to describe, this allows to specify each
and every control bit in a static manner. To make it efficient,
the table is inserted in an xarray that is global to the system,
and checked each time we trap a system register while running
a L2 guest.
Add the basic infrastructure for now, while additional patches will
implement configuration registers.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Jing Zhang <jingzhangos@google.com>
Reviewed-by: Miguel Luis <miguel.luis@oracle.com>
Link: https://lore.kernel.org/r/20230815183903.2735724-15-maz@kernel.org
Support injecting exceptions and performing exception returns to and
from virtual EL2. This must be done entirely in software except when
taking an exception from vEL0 to vEL2 when the virtual HCR_EL2.{E2H,TGE}
== {1,1} (a VHE guest hypervisor).
[maz: switch to common exception injection framework, illegal exeption
return handling]
Reviewed-by: Ganapatrao Kulkarni <gankulkarni@os.amperecomputing.com>
Signed-off-by: Jintack Lim <jintack.lim@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230209175820.1939006-10-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
