* kvm-arm64/nv-6.8-prefix:
: .
: Nested Virtualization support update, focussing on the
: NV2 support (VNCR mapping and such).
: .
KVM: arm64: nv: Handle virtual EL2 registers in vcpu_read/write_sys_reg()
KVM: arm64: nv: Map VNCR-capable registers to a separate page
KVM: arm64: nv: Add EL2_REG_VNCR()/EL2_REG_REDIR() sysreg helpers
KVM: arm64: Introduce a bad_trap() primitive for unexpected trap handling
KVM: arm64: nv: Add include containing the VNCR_EL2 offsets
KVM: arm64: nv: Add non-VHE-EL2->EL1 translation helpers
KVM: arm64: nv: Drop EL12 register traps that are redirected to VNCR
KVM: arm64: nv: Compute NV view of idregs as a one-off
KVM: arm64: nv: Hoist vcpu_has_nv() into is_hyp_ctxt()
arm64: cpufeatures: Restrict NV support to FEAT_NV2
Signed-off-by: Marc Zyngier <maz@kernel.org>
KVM internally uses accessor functions when reading or writing the
guest's system registers. This takes care of accessing either the stored
copy or using the "live" EL1 system registers when the host uses VHE.
With the introduction of virtual EL2 we add a bunch of EL2 system
registers, which now must also be taken care of:
- If the guest is running in vEL2, and we access an EL1 sysreg, we must
revert to the stored version of that, and not use the CPU's copy.
- If the guest is running in vEL1, and we access an EL2 sysreg, we must
also use the stored version, since the CPU carries the EL1 copy.
- Some EL2 system registers are supposed to affect the current execution
of the system, so we need to put them into their respective EL1
counterparts. For this we need to define a mapping between the two.
- Some EL2 system registers have a different format than their EL1
counterpart, so we need to translate them before writing them to the
CPU. This is done using an (optional) translate function in the map.
All of these cases are now wrapped into the existing accessor functions,
so KVM users wouldn't need to care whether they access EL2 or EL1
registers and also which state the guest is in.
Reviewed-by: Ganapatrao Kulkarni <gankulkarni@os.amperecomputing.com>
Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Co-developed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
With ARMv8.4-NV, registers that can be directly accessed in memory
by the guest have to live at architected offsets in a special page.
Let's annotate the sysreg enum to reflect the offset at which they
are in this page, whith a little twist:
If running on HW that doesn't have the ARMv8.4-NV feature, or even
a VM that doesn't use NV, we store all the system registers in the
usual sys_regs array. The only difference with the pre-8.4
situation is that VNCR-capable registers are at a "similar" offset
as in the VNCR page (we can compute the actual offset at compile
time), and that the sys_regs array is both bigger and sparse.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Add two helpers to deal with EL2 registers are are either redirected
to the VNCR page, or that are redirected to their EL1 counterpart.
In either cases, no trap is expected.
THe relevant register descriptors are repainted accordingly.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
In order to ease the debugging of NV, it is helpful to have the kernel
shout at you when an unexpected trap is handled. We already have this
in a couple of cases. Make this a more generic infrastructure that we
will make use of very shortly.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
VNCR_EL2 points to a page containing a number of system registers
accessed by a guest hypervisor when ARMv8.4-NV is enabled.
Let's document the offsets in that page, as we are going to use
this layout.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Some EL2 system registers immediately affect the current execution
of the system, so we need to use their respective EL1 counterparts.
For this we need to define a mapping between the two. In general,
this only affects non-VHE guest hypervisors, as VHE system registers
are compatible with the EL1 counterparts.
These helpers will get used in subsequent patches.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Co-developed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
With FEAT_NV2, a bunch of system register writes are turned into
memory writes. This is specially the fate of the EL12 registers
that the guest hypervisor manipulates out of context.
Remove the trap descriptors for those, as they are never going
to be used again.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Now that we have a full copy of the idregs for each VM, there is
no point in repainting the sysregs on each access. Instead, we
can simply perform the transmation as a one-off and be done
with it.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
A rather common idiom when writing NV code as part of KVM is
to have things such has:
if (vcpu_has_nv(vcpu) && is_hyp_ctxt(vcpu)) {
[...]
}
to check that we are in a hyp-related context. The second part of
the conjunction would be enough, but the first one contains a
static key that allows the rest of the checkis to be elided when
in a non-NV environment.
Rewrite is_hyp_ctxt() to directly use vcpu_has_nv(). The result
is the same, and the code easier to read. The one occurence of
this that is already merged is rewritten in the process.
In order to avoid nasty cirtular dependencies between kvm_emulate.h
and kvm_nested.h, vcpu_has_feature() is itself hoisted into kvm_host.h,
at the cost of some #deferry...
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
To anyone who has played with FEAT_NV, it is obvious that the level
of performance is rather low due to the trap amplification that it
imposes on the host hypervisor. FEAT_NV2 solves a number of the
problems that FEAT_NV had.
It also turns out that all the existing hardware that has FEAT_NV
also has FEAT_NV2. Finally, it is now allowed by the architecture
to build FEAT_NV2 *only* (as denoted by ID_AA64MMFR4_EL1.NV_frac),
which effectively seals the fate of FEAT_NV.
Restrict the NV support to NV2, and be done with it. Nobody will
cry over the old crap. NV_frac will eventually be supported once
the intrastructure is ready.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
* kvm-arm64/fgt-rework: (30 commits)
: .
: Fine Grain Trapping update, courtesy of Fuad Tabba.
:
: From the cover letter:
:
: "This patch series has fixes, updates, and code for validating
: fine grain trap register masks, as well as some fixes to feature
: trapping in pKVM.
:
: New fine grain trap (FGT) bits have been defined in the latest
: Arm Architecture System Registers xml specification (DDI0601 and
: DDI0602 2023-09) [1], so the code is updated to reflect them.
: Moreover, some of the already-defined masks overlap with RES0,
: which this series fixes.
:
: It also adds FGT register masks that weren't defined earlier,
: handling of HAFGRTR_EL2 in nested virt, as well as build time
: validation that the bits of the various masks are all accounted
: for and without overlap."
:
: This branch also drags the arm64/for-next/sysregs branch,
: which is a dependency on this work.
: .
KVM: arm64: Trap external trace for protected VMs
KVM: arm64: Mark PAuth as a restricted feature for protected VMs
KVM: arm64: Fix which features are marked as allowed for protected VMs
KVM: arm64: Macros for setting/clearing FGT bits
KVM: arm64: Define FGT nMASK bits relative to other fields
KVM: arm64: Use generated FGT RES0 bits instead of specifying them
KVM: arm64: Add build validation for FGT trap mask values
KVM: arm64: Update and fix FGT register masks
KVM: arm64: Handle HAFGRTR_EL2 trapping in nested virt
KVM: arm64: Add bit masks for HAFGRTR_EL2
KVM: arm64: Add missing HFGITR_EL2 FGT entries to nested virt
KVM: arm64: Add missing HFGxTR_EL2 FGT entries to nested virt
KVM: arm64: Explicitly trap unsupported HFGxTR_EL2 features
arm64/sysreg: Add missing system instruction definitions for FGT
arm64/sysreg: Add missing system register definitions for FGT
arm64/sysreg: Add missing ExtTrcBuff field definition to ID_AA64DFR0_EL1
arm64/sysreg: Add missing Pauth_LR field definitions to ID_AA64ISAR1_EL1
arm64/sysreg: Add new system registers for GCS
arm64/sysreg: Add definition for FPMR
arm64/sysreg: Update HCRX_EL2 definition for DDI0601 2023-09
...
Signed-off-by: Marc Zyngier <maz@kernel.org>
* kvm-arm64/lpa2:
: .
: Support FEAT_LPA2 at EL2 S1 and S2, courtesy of Ryan Roberts
:
: From the cover letter:
:
: "This adds support for FEAT_LPA2 to KVM for both hypervisor stage 1 (for the
: nvhe/protected modes) and the vm stage 2 translation tables (for all modes).
: FEAT_LPA2 enables 52 bit PAs and VAs for 4KB and 16KB granules (note this is
: already supported for 64KB granules via the FEAT_LPA and FEAT_LVA extensions)."
: .
KVM: arm64: Use helpers to classify exception types reported via ESR
KVM: selftests: arm64: Support P52V48 4K and 16K guest_modes
KVM: selftests: arm64: Determine max ipa size per-page size
KVM: arm64: Allow guests with >48-bit IPA size on FEAT_LPA2 systems
KVM: arm64: Support up to 5 levels of translation in kvm_pgtable
KVM: arm64: Convert translation level parameter to s8
KVM: arm64: Use LPA2 page-tables for stage2 and hyp stage1
KVM: arm64: Add new (V)TCR_EL2 field definitions for FEAT_LPA2
arm64: Add ARM64_HAS_LPA2 CPU capability
arm64/mm: Add FEAT_LPA2 specific ID_AA64MMFR0.TGRAN[2]
arm64/mm: Update tlb invalidation routines for FEAT_LPA2
arm64/mm: Add lpa2_is_enabled() kvm_lpa2_is_enabled() stubs
arm64/mm: Modify range-based tlbi to decrement scale
Signed-off-by: Marc Zyngier <maz@kernel.org>
pKVM does not support external trace for protected VMs. Trap
external trace, and add the ExtTrcBuff to make it possible to
check for the feature.
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231214100158.2305400-18-tabba@google.com
Protected VMs will only support basic PAuth (FEAT_PAuth). Mark it
as restricted to ensure that later versions aren't supported for
protected guests.
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231214100158.2305400-17-tabba@google.com
Cache maintenance operations are not trapped for protected VMs,
and shouldn't be. Mark them as allowed.
Moreover, features advertised by ID_AA64PFR2 and ID_AA64MMFR3 are
(already) not allowed, mark them as such.
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231214100158.2305400-16-tabba@google.com
There's a lot of boilerplate code for setting and clearing FGT
bits when activating guest traps. Refactor it into macros. These
macros will also be used in future patch series.
No functional change intended.
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231214100158.2305400-15-tabba@google.com
Now that RES0 and MASK have full coverage, no need to manually
encode nMASK. Calculate it relative to the other fields.
No functional change intended.
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231214100158.2305400-14-tabba@google.com
Now that all FGT fields are accounted for and represented, use
the generated value instead of manually specifying them.
For __HFGWTR_EL2_RES0, however, there is no generated value. Its
fields are subset of HFGRTR_EL2, with the remaining being RES0.
Therefore, add a mask that represents the HFGRTR_EL2 only bits
and define __HFGWTR_EL2_* using those and the __HFGRTR_EL2_*
fields.
No functional change intended.
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231214100158.2305400-13-tabba@google.com
These checks help ensure that all the bits are accounted for,
that there hasn't been a transcribing error from the spec nor
from the generated mask values, which will be used in subsequent
patches.
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231214100158.2305400-12-tabba@google.com
New trap bits have been defined since the latest update to this
patch. Moreover, the existing definitions of some of the mask
and the RES0 bits overlap, which could be wrong, confusing, or
both.
Update the bits based on DDI0601 2023-09, and ensure that the
existing bits are consistent.
Subsequent patches will use the generated RES0 fields instead of
specifying them manually. This patch keeps the manual encoding of
the bits to make it easier to review the series.
Fixes: 0fd7686500 ("KVM: arm64: Add nPIR{E0}_EL1 to HFG traps")
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231214100158.2305400-11-tabba@google.com
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
To support HAFGRTR_EL2 supported in nested virt in the following
patch, first add its bitmask definitions based on DDI0601 2023-09.
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/20231214100158.2305400-9-tabba@google.com
Do not rely on the value of __HFGRTR_EL2_nMASK to trap
unsupported features, since the nMASK can (and will) change as
new traps are added and as its value is updated. Instead,
explicitly specify the trap bits.
Suggested-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231214100158.2305400-6-tabba@google.com
Add the definitions of missing system instructions that are
trappable by fine grain traps. The definitions are based on
DDI0602 2023-09.
Signed-off-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20231214100158.2305400-5-tabba@google.com
Signed-off-by: Will Deacon <will@kernel.org>
Add the definitions of missing system registers that are
trappable by fine grain traps. The definitions are based on
DDI0601 2023-09.
Signed-off-by: Fuad Tabba <tabba@google.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20231214100158.2305400-4-tabba@google.com
Signed-off-by: Will Deacon <will@kernel.org>
Add the ExtTrcBuff field definitions to ID_AA64DFR0_EL1 from
DDI0601 2023-09.
This field isn't used yet. Adding it for completeness and because
it will be used in future patches.
Signed-off-by: Fuad Tabba <tabba@google.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20231214100158.2305400-3-tabba@google.com
Signed-off-by: Will Deacon <will@kernel.org>
Add the Pauth_LR field definitions to ID_AA64ISAR1_EL1, based on
DDI0601 2023-09.
These fields aren't used yet. Adding them for completeness and
consistency (definition already exists for ID_AA64ISAR2_EL1).
Signed-off-by: Fuad Tabba <tabba@google.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20231214100158.2305400-2-tabba@google.com
Signed-off-by: Will Deacon <will@kernel.org>
DDI0601 2023-09 defines a new sysrem register FPMR (Floating Point Mode
Register) which configures the new FP8 features. Add a definition of this
register.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20231209-b4-arm64-sysreg-additions-v1-12-45284e538474@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
DDI0601 2023-09 defines new fields in HCRX_EL2 controlling access to new
system registers, update our definition of HCRX_EL2 to reflect this.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20231209-b4-arm64-sysreg-additions-v1-11-45284e538474@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
DDI0601 2023-09 defines some new fields in SCTLR_EL1 controlling new MTE
and floating point features. Update our sysreg definition to reflect these.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20231209-b4-arm64-sysreg-additions-v1-10-45284e538474@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
DDI0601 2023-09 defines a new feature register ID_AA64FPFR0_EL1 which
enumerates a number of FP8 related features. Add a definition for it.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20231209-b4-arm64-sysreg-additions-v1-8-45284e538474@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
DDI0601 2023-09 adds a new system register ID_AA64ISAR3_EL1 enumerating
new floating point and TLB invalidation features. Add a defintion for it.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20231209-b4-arm64-sysreg-additions-v1-7-45284e538474@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
DDI0601 2023-09 defines some new fields in previously RES0 space in
ID_AA64ISAR2_EL1, together with one new enum value. Update the system
register definition to reflect this.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20231209-b4-arm64-sysreg-additions-v1-6-45284e538474@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
DDI0601 2023-09 defines a new system register ID_AA64PFR2_EL1 which
enumerates FPMR and some new MTE features. Add a definition of this
register.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20231209-b4-arm64-sysreg-additions-v1-5-45284e538474@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Add E0POE bit that traps accesses to POR_EL0 from EL0.
Updated according to DDI0601 2023-03.
Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20231209-b4-arm64-sysreg-additions-v1-4-45284e538474@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Add POR_EL{0,1} according to DDI0601 2023-03.
Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20231209-b4-arm64-sysreg-additions-v1-3-45284e538474@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
The 2023-09 release of the architecture XML (DDI0601) adds a new field
ATS1E1A to HFGITR_EL2, update our definition of the register to match.
This was extracted from Faud Tabba's patch "KVM: arm64: Add latest
HFGITR_EL2 FGT entries to nested virt"
[Extracted the sysreg definition from Faud's original patch and reword
subject to match -- broonie]
Signed-off-by: Fuad Tabba <tabba@google.com>
Message-Id: <20231206100503.564090-4-tabba@google.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20231209-b4-arm64-sysreg-additions-v1-1-45284e538474@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Currently, we rely on the fact that exceptions can be trivially
classified by applying a mask/value pair to the syndrome value reported
via the ESR register, but this will no longer be true once we enable
support for 5 level paging.
So introduce a couple of helpers that encapsulate this mask/value pair
matching, and wire them up in the code. No functional change intended,
the actual handling of translation level -1 will be added in a
subsequent patch.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
[maz: folded in changes suggested by Mark]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231128140400.3132145-2-ardb@google.com
Add support for VM_MODE_P52V48_4K and VM_MODE_P52V48_16K guest modes by
using the FEAT_LPA2 pte format for stage1, when FEAT_LPA2 is available.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231127111737.1897081-13-ryan.roberts@arm.com
We are about to add 52 bit PA guest modes for 4K and 16K pages when the
system supports LPA2. In preparation beef up the logic that parses mmfr0
to also tell us what the maximum supported PA size is for each page
size. Max PA size = 0 implies the page size is not supported at all.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231127111737.1897081-12-ryan.roberts@arm.com
With all the page-table infrastructure in place, we can finally increase
the maximum permisable IPA size to 52-bits on 4KB and 16KB page systems
that have FEAT_LPA2.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231127111737.1897081-11-ryan.roberts@arm.com
FEAT_LPA2 increases the maximum levels of translation from 4 to 5 for
the 4KB page case, when IA is >48 bits. While we can still use 4 levels
for stage2 translation in this case (due to stage2 allowing concatenated
page tables for first level lookup), the same kvm_pgtable library is
used for the hyp stage1 page tables and stage1 does not support
concatenation.
Therefore, modify the library to support up to 5 levels. Previous
patches already laid the groundwork for this by refactoring code to work
in terms of KVM_PGTABLE_FIRST_LEVEL and KVM_PGTABLE_LAST_LEVEL. So we
just need to change these macros.
The hardware sometimes encodes the new level differently from the
others: One such place is when reading the level from the FSC field in
the ESR_EL2 register. We never expect to see the lowest level (-1) here
since the stage 2 page tables always use concatenated tables for first
level lookup and therefore only use 4 levels of lookup. So we get away
with just adding a comment to explain why we are not being careful about
decoding level -1.
For stage2 VTCR_EL2.SL2 is introduced to encode the new start level.
However, since we always use concatenated page tables for first level
look up at stage2 (and therefore we will never need the new extra level)
we never touch this new field.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231127111737.1897081-10-ryan.roberts@arm.com
With the introduction of FEAT_LPA2, the Arm ARM adds a new level of
translation, level -1, so levels can now be in the range [-1;3]. 3 is
always the last level and the first level is determined based on the
number of VA bits in use.
Convert level variables to use a signed type in preparation for
supporting this new level -1.
Since the last level is always anchored at 3, and the first level varies
to suit the number of VA/IPA bits, take the opportunity to replace
KVM_PGTABLE_MAX_LEVELS with the 2 macros KVM_PGTABLE_FIRST_LEVEL and
KVM_PGTABLE_LAST_LEVEL. This removes the assumption from the code that
levels run from 0 to KVM_PGTABLE_MAX_LEVELS - 1, which will soon no
longer be true.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231127111737.1897081-9-ryan.roberts@arm.com
