KVM: arm64: nv: Plumb handling of GICv3 EL2 accesses

Wire the handling of all GICv3 EL2 registers, and provide emulation
for all the non memory-backed registers (ICC_SRE_EL2, ICH_VTR_EL2,
ICH_MISR_E

KVM: arm64: nv: Plumb handling of GICv3 EL2 accesses

Wire the handling of all GICv3 EL2 registers, and provide emulation
for all the non memory-backed registers (ICC_SRE_EL2, ICH_VTR_EL2,
ICH_MISR_EL2, ICH_ELRSR_EL2, and ICH_EISR_EL2).

Signed-off-by: Marc Zyngier <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Oliver Upton <[email protected]>

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KVM: arm64: Register ptdump with debugfs on guest creation

While arch/*/mem/ptdump handles the kernel pagetable dumping code,
introduce KVM/ptdump to show the guest stage-2 pagetables. The
separatio

KVM: arm64: Register ptdump with debugfs on guest creation

While arch/*/mem/ptdump handles the kernel pagetable dumping code,
introduce KVM/ptdump to show the guest stage-2 pagetables. The
separation is necessary because most of the definitions from the
stage-2 pagetable reside in the KVM path and we will be invoking
functionality specific to KVM. Introduce the PTDUMP_STAGE2_DEBUGFS config.

When a guest is created, register a new file entry under the guest
debugfs dir which allows userspace to show the contents of the guest
stage-2 pagetables when accessed.

[maz: moved function prototypes from kvm_host.h to kvm_mmu.h]

Signed-off-by: Sebastian Ene <[email protected]>
Reviewed-by: Vincent Donnefort <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Marc Zyngier <[email protected]>

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KVM: arm64: nv: Add basic emulation of AT S1E{0,1}{R,W}

Emulating AT instructions is one the tasks devolved to the host
hypervisor when NV is on.

Here, we take the basic approach of emulating AT S1

KVM: arm64: nv: Add basic emulation of AT S1E{0,1}{R,W}

Emulating AT instructions is one the tasks devolved to the host
hypervisor when NV is on.

Here, we take the basic approach of emulating AT S1E{0,1}{R,W}
using the AT instructions themselves. While this mostly work,
it doesn't *always* work:

- S1 page tables can be swapped out

- shadow S2 can be incomplete and not contain mappings for
the S1 page tables

We are not trying to handle these case here, and defer it to
a later patch. Suitable comments indicate where we are in dire
need of better handling.

Co-developed-by: Jintack Lim <[email protected]>
Signed-off-by: Jintack Lim <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>

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KVM: arm64: fix override-init warnings in W=1 builds

Add -Wno-override-init to the build flags for sys_regs.c,
handle_exit.c, and switch.c to fix warnings like the following:

arch/arm64/kvm/hyp/vhe

KVM: arm64: fix override-init warnings in W=1 builds

Add -Wno-override-init to the build flags for sys_regs.c,
handle_exit.c, and switch.c to fix warnings like the following:

arch/arm64/kvm/hyp/vhe/switch.c:271:43: warning: initialized field overwritten [-Woverride-init]
271 | [ESR_ELx_EC_CP15_32] = kvm_hyp_handle_cp15_32,
|

Signed-off-by: Sebastian Ott <[email protected]>
Reviewed-by: Marc Zyngier <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Oliver Upton <[email protected]>

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kbuild: use $(src) instead of $(srctree)/$(src) for source directory

Kbuild conventionally uses $(obj)/ for generated files, and $(src)/ for
checked-in source files. It is merely a convention withou

kbuild: use $(src) instead of $(srctree)/$(src) for source directory

Kbuild conventionally uses $(obj)/ for generated files, and $(src)/ for
checked-in source files. It is merely a convention without any functional
difference. In fact, $(obj) and $(src) are exactly the same, as defined
in scripts/Makefile.build:

src := $(obj)

When the kernel is built in a separate output directory, $(src) does
not accurately reflect the source directory location. While Kbuild
resolves this discrepancy by specifying VPATH=$(srctree) to search for
source files, it does not cover all cases. For example, when adding a
header search path for local headers, -I$(srctree)/$(src) is typically
passed to the compiler.

This introduces inconsistency between upstream and downstream Makefiles
because $(src) is used instead of $(srctree)/$(src) for the latter.

To address this inconsistency, this commit changes the semantics of
$(src) so that it always points to the directory in the source tree.

Going forward, the variables used in Makefiles will have the following
meanings:

$(obj) - directory in the object tree
$(src) - directory in the source tree (changed by this commit)
$(objtree) - the top of the kernel object tree
$(srctree) - the top of the kernel source tree

Consequently, $(srctree)/$(src) in upstream Makefiles need to be replaced
with $(src).

Signed-off-by: Masahiro Yamada <[email protected]>
Reviewed-by: Nicolas Schier <[email protected]>

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KVM: arm64: nv: Add emulation for ERETAx instructions

FEAT_NV has the interesting property of relying on ERET being
trapped. An added complexity is that it also traps ERETAA and
ERETAB, meaning that

KVM: arm64: nv: Add emulation for ERETAx instructions

FEAT_NV has the interesting property of relying on ERET being
trapped. An added complexity is that it also traps ERETAA and
ERETAB, meaning that the Pointer Authentication aspect of these
instruction must be emulated.

Add an emulation of Pointer Authentication, limited to ERETAx
(always using SP_EL2 as the modifier and ELR_EL2 as the pointer),
using the Generic Authentication instructions.

The emulation, however small, is placed in its own compilation
unit so that it can be avoided if the configuration doesn't
include it (or the toolchan in not up to the task).

Reviewed-by: Joey Gouly <[email protected]>
Reviewed-by: Oliver Upton <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Marc Zyngier <[email protected]>

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KVM: arm64: nv: Filter out unsupported features from ID regs

As there is a number of features that we either can't support,
or don't want to support right away with NV, let's add some
basic filterin

KVM: arm64: nv: Filter out unsupported features from ID regs

As there is a number of features that we either can't support,
or don't want to support right away with NV, let's add some
basic filtering so that we don't advertize silly things to the
EL2 guest.

Whilst we are at it, advertize FEAT_TTL as well as FEAT_GTG, which
the NV implementation will implement.

Reviewed-by: Ganapatrao Kulkarni <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Oliver Upton <[email protected]>

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KVM: arm64: nv: Support virtual EL2 exceptions

Support injecting exceptions and performing exception returns to and
from virtual EL2. This must be done entirely in software except when
taking an ex

KVM: arm64: nv: Support virtual EL2 exceptions

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 <[email protected]>
Signed-off-by: Jintack Lim <[email protected]>
Signed-off-by: Christoffer Dall <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Oliver Upton <[email protected]>

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KVM: arm64: Move nVHE stacktrace unwinding into its own compilation unit

The unwinding code doesn't really belong to the exit handling
code. Instead, move it to a file (conveniently named stacktrace

KVM: arm64: Move nVHE stacktrace unwinding into its own compilation unit

The unwinding code doesn't really belong to the exit handling
code. Instead, move it to a file (conveniently named stacktrace.c
to confuse the reviewer), and move all the stacktrace-related
stuff there.

It will be joined by more code very soon.

Signed-off-by: Marc Zyngier <[email protected]>
Reviewed-by: Kalesh Singh <[email protected]>
Tested-by: Kalesh Singh <[email protected]>
Reviewed-by: Oliver Upton <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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KVM: arm64: pmu: Restore compilation when HW_PERF_EVENTS isn't selected

Moving kvm_pmu_events into the vcpu (and refering to it) broke the
somewhat unusual case where the kernel has no support for a

KVM: arm64: pmu: Restore compilation when HW_PERF_EVENTS isn't selected

Moving kvm_pmu_events into the vcpu (and refering to it) broke the
somewhat unusual case where the kernel has no support for a PMU
at all.

In order to solve this, move things around a bit so that we can
easily avoid refering to the pmu structure outside of PMU-aware
code. As a bonus, pmu.c isn't compiled in when HW_PERF_EVENTS
isn't selected.

Reported-by: kernel test robot <[email protected]>
Reviewed-by: Fuad Tabba <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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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 invalida

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 <[email protected]>
Signed-off-by: Shameer Kolothum <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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KVM: arm64: Use Makefile.kvm for common files

Signed-off-by: David Woodhouse <[email protected]>
Acked-by: Marc Zyngier <[email protected]>
Message-Id: <[email protected]>
Signe

KVM: arm64: Use Makefile.kvm for common files

Signed-off-by: David Woodhouse <[email protected]>
Acked-by: Marc Zyngier <[email protected]>
Message-Id: <[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>

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KVM: arm64: Move host EL1 code out of hyp/ directory

kvm/hyp/reserved_mem.c contains host code executing at EL1 and is not
linked into the hypervisor object. Move the file into kvm/pkvm.c and
rework

KVM: arm64: Move host EL1 code out of hyp/ directory

kvm/hyp/reserved_mem.c contains host code executing at EL1 and is not
linked into the hypervisor object. Move the file into kvm/pkvm.c and
rework the headers so that the definitions shared between the host and
the hypervisor live in asm/kvm_pkvm.h.

Signed-off-by: Will Deacon <[email protected]>
Tested-by: Fuad Tabba <[email protected]>
Reviewed-by: Fuad Tabba <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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KVM: arm64: Generate hyp_constants.h for the host

In order to avoid exposing hypervisor (EL2) data structures directly to
the host, generate hyp_constants.h to provide constants such as structure
si

KVM: arm64: Generate hyp_constants.h for the host

In order to avoid exposing hypervisor (EL2) data structures directly to
the host, generate hyp_constants.h to provide constants such as structure
sizes to the host without dragging in the definitions themselves.

Signed-off-by: Will Deacon <[email protected]>
Tested-by: Fuad Tabba <[email protected]>
Reviewed-by: Fuad Tabba <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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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:

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 <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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KVM: stats: Add fd-based API to read binary stats data

This commit defines the API for userspace and prepare the common
functionalities to support per VM/VCPU binary stats data readings.

The KVM st

KVM: stats: Add fd-based API to read binary stats data

This commit defines the API for userspace and prepare the common
functionalities to support per VM/VCPU binary stats data readings.

The KVM stats now is only accessible by debugfs, which has some
shortcomings this change series are supposed to fix:
1. The current debugfs stats solution in KVM could be disabled
when kernel Lockdown mode is enabled, which is a potential
rick for production.
2. The current debugfs stats solution in KVM is organized as "one
stats per file", it is good for debugging, but not efficient
for production.
3. The stats read/clear in current debugfs solution in KVM are
protected by the global kvm_lock.

Besides that, there are some other benefits with this change:
1. All KVM VM/VCPU stats can be read out in a bulk by one copy
to userspace.
2. A schema is used to describe KVM statistics. From userspace's
perspective, the KVM statistics are self-describing.
3. With the fd-based solution, a separate telemetry would be able
to read KVM stats in a less privileged environment.
4. After the initial setup by reading in stats descriptors, a
telemetry only needs to read the stats data itself, no more
parsing or setup is needed.

Reviewed-by: David Matlack <[email protected]>
Reviewed-by: Ricardo Koller <[email protected]>
Reviewed-by: Krish Sadhukhan <[email protected]>
Reviewed-by: Fuad Tabba <[email protected]>
Tested-by: Fuad Tabba <[email protected]> #arm64
Signed-off-by: Jing Zhang <[email protected]>
Message-Id: <[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>

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KVM: arm64: Implement the TRNG hypervisor call

Provide a hypervisor implementation of the ARM architected TRNG firmware
interface described in ARM spec DEN0098. All function IDs are implemented,
inc

KVM: arm64: Implement the TRNG hypervisor call

Provide a hypervisor implementation of the ARM architected TRNG firmware
interface described in ARM spec DEN0098. All function IDs are implemented,
including both 32-bit and 64-bit versions of the TRNG_RND service, which
is the centerpiece of the API.

The API is backed by the kernel's entropy pool only, to avoid guests
draining more precious direct entropy sources.

Signed-off-by: Ard Biesheuvel <[email protected]>
[Andre: minor fixes, drop arch_get_random() usage]
Signed-off-by: Andre Przywara <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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KVM: arm64: Replace KVM_ARM_PMU with HW_PERF_EVENTS

KVM_ARM_PMU only existed for the benefit of 32bit ARM hosts,
and makes no sense now that we are 64bit only. Get rid of it.

Signed-off-by: Marc Zy

KVM: arm64: Replace KVM_ARM_PMU with HW_PERF_EVENTS

KVM_ARM_PMU only existed for the benefit of 32bit ARM hosts,
and makes no sense now that we are 64bit only. Get rid of it.

Signed-off-by: Marc Zyngier <[email protected]>

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KVM: arm64: Get rid of the AArch32 register mapping code

The only use of the register mapping code was for the sake of the LR
mapping, which we trivially solved in a previous patch. Get rid of
the w

KVM: arm64: Get rid of the AArch32 register mapping code

The only use of the register mapping code was for the sake of the LR
mapping, which we trivially solved in a previous patch. Get rid of
the whole thing now.

Signed-off-by: Marc Zyngier <[email protected]>

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KVM: arm64: Consolidate exception injection

Move the AArch32 exception injection code back into the inject_fault.c
file, removing the need for a few non-static functions now that AArch32
host suppor

KVM: arm64: Consolidate exception injection

Move the AArch32 exception injection code back into the inject_fault.c
file, removing the need for a few non-static functions now that AArch32
host support is a thing of the past.

Signed-off-by: Marc Zyngier <[email protected]>

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KVM: arm64: nVHE: Migrate hyp-init to SMCCC

To complete the transition to SMCCC, the hyp initialization is given a
function ID. This looks neater than comparing the hyp stub function IDs
to the page

KVM: arm64: nVHE: Migrate hyp-init to SMCCC

To complete the transition to SMCCC, the hyp initialization is given a
function ID. This looks neater than comparing the hyp stub function IDs
to the page table physical address.

Some care is taken to only clobber x0-3 before the host context is saved
as only those registers can be clobbered accoring to SMCCC. Fortunately,
only a few acrobatics are needed. The possible new tpidr_el2 is moved to
the argument in x2 so that it can be stashed in tpidr_el2 early to free
up a scratch register. The page table configuration then makes use of
x0-2.

Signed-off-by: Andrew Scull <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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KVM: arm64: Move hyp-init.S to nVHE

hyp-init.S contains the identity mapped initialisation code for the
non-VHE code that runs at EL2. It is only used for non-VHE.

Adjust code that calls into this

KVM: arm64: Move hyp-init.S to nVHE

hyp-init.S contains the identity mapped initialisation code for the
non-VHE code that runs at EL2. It is only used for non-VHE.

Adjust code that calls into this to use the prefixed symbol name.

Signed-off-by: Andrew Scull <[email protected]>
Signed-off-by: David Brazdil <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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KVM: arm64: Remove the target table

Finally, remove the target table. Merge the code that checks the
tables into kvm_reset_sys_regs() as there is now only one table.

Signed-off-by: James Morse <jam

KVM: arm64: Remove the target table

Finally, remove the target table. Merge the code that checks the
tables into kvm_reset_sys_regs() as there is now only one table.

Signed-off-by: James Morse <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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KVM: arm64: Clean up kvm makefiles

Consolidate references to the CONFIG_KVM configuration item to encompass
entire folders rather than per line.

Signed-off-by: Fuad Tabba <[email protected]>
Signed-

KVM: arm64: Clean up kvm makefiles

Consolidate references to the CONFIG_KVM configuration item to encompass
entire folders rather than per line.

Signed-off-by: Fuad Tabba <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Acked-by: Will Deacon <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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KVM: arm64: Kill off CONFIG_KVM_ARM_HOST

CONFIG_KVM_ARM_HOST is just a proxy for CONFIG_KVM, so remove it in favour
of the latter.

Signed-off-by: Will Deacon <[email protected]>
Signed-off-by: Fuad T

KVM: arm64: Kill off CONFIG_KVM_ARM_HOST

CONFIG_KVM_ARM_HOST is just a proxy for CONFIG_KVM, so remove it in favour
of the latter.

Signed-off-by: Will Deacon <[email protected]>
Signed-off-by: Fuad Tabba <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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