Commit Graph

47 Commits

Author SHA1 Message Date
Oliver Upton
0d46e324c0 Merge branch 'kvm-arm64/vgic-v4-ctl' into kvmarm/next
* kvm-arm64/vgic-v4-ctl:
  : Userspace control of nASSGIcap, courtesy of Raghavendra Rao Ananta
  :
  : Allow userspace to decide if support for SGIs without an active state is
  : advertised to the guest, allowing VMs from GICv3-only hardware to be
  : migrated to to GICv4.1 capable machines.
  Documentation: KVM: arm64: Describe VGICv3 registers writable pre-init
  KVM: arm64: selftests: Add test for nASSGIcap attribute
  KVM: arm64: vgic-v3: Allow userspace to write GICD_TYPER2.nASSGIcap
  KVM: arm64: vgic-v3: Allow access to GICD_IIDR prior to initialization
  KVM: arm64: vgic-v3: Consolidate MAINT_IRQ handling
  KVM: arm64: Disambiguate support for vSGIs v. vLPIs

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2025-07-28 08:11:38 -07:00
Oliver Upton
a7f49a9bf4 Merge branch 'kvm-arm64/el2-reg-visibility' into kvmarm/next
* kvm-arm64/el2-reg-visibility:
  : Fixes to EL2 register visibility, courtesy of Marc Zyngier
  :
  :  - Expose EL2 VGICv3 registers via the VGIC attributes accessor, not the
  :    KVM_{GET,SET}_ONE_REG ioctls
  :
  :  - Condition visibility of FGT registers on the presence of FEAT_FGT in
  :    the VM
  KVM: arm64: selftest: vgic-v3: Add basic GICv3 sysreg userspace access test
  KVM: arm64: Enforce the sorting of the GICv3 system register table
  KVM: arm64: Clarify the check for reset callback in check_sysreg_table()
  KVM: arm64: vgic-v3: Fix ordering of ICH_HCR_EL2
  KVM: arm64: Document registers exposed via KVM_DEV_ARM_VGIC_GRP_CPU_SYSREGS
  KVM: arm64: selftests: get-reg-list: Add base EL2 registers
  KVM: arm64: selftests: get-reg-list: Simplify feature dependency
  KVM: arm64: Advertise FGT2 registers to userspace
  KVM: arm64: Condition FGT registers on feature availability
  KVM: arm64: Expose GICv3 EL2 registers via KVM_DEV_ARM_VGIC_GRP_CPU_SYSREGS
  KVM: arm64: Let GICv3 save/restore honor visibility attribute
  KVM: arm64: Define helper for ICH_VTR_EL2
  KVM: arm64: Define constant value for ICC_SRE_EL2
  KVM: arm64: Don't advertise ICH_*_EL2 registers through GET_ONE_REG
  KVM: arm64: Make RVBAR_EL2 accesses UNDEF

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2025-07-28 08:06:38 -07:00
Raghavendra Rao Ananta
c652887a92 KVM: arm64: vgic-v3: Allow userspace to write GICD_TYPER2.nASSGIcap
KVM unconditionally advertises GICD_TYPER2.nASSGIcap (which internally
implies vSGIs) on GICv4.1 systems. Allow userspace to change whether a
VM supports the feature. Only allow changes prior to VGIC initialization
as at that point vPEs need to be allocated for the VM.

For convenience, bundle support for vLPIs and vSGIs behind this feature,
allowing userspace to control vPE allocation for VMs in environments
that may be constrained on vPE IDs.

Signed-off-by: Raghavendra Rao Ananta <rananta@google.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20250724062805.2658919-5-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2025-07-26 08:45:52 -07:00
Oliver Upton
82221a4e66 KVM: arm64: Disambiguate support for vSGIs v. vLPIs
vgic_supports_direct_msis() is a bit of a misnomer, as it returns true
if either vSGIs or vLPIs are supported. Pick it apart into a few
predicates and replace some open-coded checks for vSGIs, including an
opportunistic fix to always check if the CPUIF is capable of handling
vSGIs.

Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20250724062805.2658919-2-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2025-07-26 08:37:45 -07:00
Marc Zyngier
8af3e8ab09 KVM: arm64: Enforce the sorting of the GICv3 system register table
In order to avoid further embarassing bugs, enforce that the GICv3
sysreg table is actually sorted, just like all the other tables.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Sebastian Ott <sebott@redhat.com>
Link: https://lore.kernel.org/r/20250718111154.104029-4-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2025-07-26 08:36:58 -07:00
Marc Zyngier
ce7a1cff2e KVM: arm64: Define helper for ICH_VTR_EL2
Move the computation of the ICH_VTR_EL2 value to a common location,
so that it can be reused by the save/restore code.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20250714122634.3334816-5-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2025-07-15 20:24:29 -07:00
Marc Zyngier
c6ef468610 KVM: arm64: Define constant value for ICC_SRE_EL2
Move the bag of bits defining the value of ICC_SRE_EL2 to a common
spot so that it can be reused by the save/restore code.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20250714122634.3334816-4-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2025-07-15 20:24:29 -07:00
Sascha Bischoff
ff2aa6495d KVM: arm64: gic-v5: Probe for GICv5
Add in a probe function for GICv5 which enables support for GICv3
guests on a GICv5 host, if FEAT_GCIE_LEGACY is supported by the
hardware.

Co-authored-by: Timothy Hayes <timothy.hayes@arm.com>
Signed-off-by: Timothy Hayes <timothy.hayes@arm.com>
Signed-off-by: Sascha Bischoff <sascha.bischoff@arm.com>
Link: https://lore.kernel.org/r/20250627100847.1022515-6-sascha.bischoff@arm.com
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2025-07-08 14:41:06 -07:00
Sascha Bischoff
c017e49ed1 KVM: arm64: gic-v5: Support GICv3 compat
Add support for GICv3 compat mode (FEAT_GCIE_LEGACY) which allows a
GICv5 host to run GICv3-based VMs. This change enables the
VHE/nVHE/hVHE/protected modes, but does not support nested
virtualization.

A lazy-disable approach is taken for compat mode; it is enabled on the
vgic_v3_load path but not disabled on the vgic_v3_put path. A
non-GICv3 VM, i.e., one based on GICv5, is responsible for disabling
compat mode on the corresponding vgic_v5_load path. Currently, GICv5
is not supported, and hence compat mode is not disabled again once it
is enabled, and this function is intentionally omitted from the code.

Co-authored-by: Timothy Hayes <timothy.hayes@arm.com>
Signed-off-by: Timothy Hayes <timothy.hayes@arm.com>
Signed-off-by: Sascha Bischoff <sascha.bischoff@arm.com>
Link: https://lore.kernel.org/r/20250627100847.1022515-5-sascha.bischoff@arm.com
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2025-07-08 14:41:06 -07:00
Jing Zhang
30deb51a67 KVM: arm64: vgic-its: Add debugfs interface to expose ITS tables
This commit introduces a debugfs interface to display the contents of the
VGIC Interrupt Translation Service (ITS) tables.

The ITS tables map Device/Event IDs to Interrupt IDs and target processors.
Exposing this information through debugfs allows for easier inspection and
debugging of the interrupt routing configuration.

The debugfs interface presents the ITS table data in a tabular format:

    Device ID: 0x0, Event ID Range: [0 - 31]
    EVENT_ID    INTID  HWINTID   TARGET   COL_ID HW
    -----------------------------------------------
           0     8192        0        0        0  0
           1     8193        0        0        0  0
           2     8194        0        2        2  0

    Device ID: 0x18, Event ID Range: [0 - 3]
    EVENT_ID    INTID  HWINTID   TARGET   COL_ID HW
    -----------------------------------------------
           0     8225        0        0        0  0
           1     8226        0        1        1  0
           2     8227        0        3        3  0

    Device ID: 0x10, Event ID Range: [0 - 7]
    EVENT_ID    INTID  HWINTID   TARGET   COL_ID HW
    -----------------------------------------------
           0     8229        0        3        3  1
           1     8230        0        0        0  1
           2     8231        0        1        1  1
           3     8232        0        2        2  1
           4     8233        0        3        3  1

The output is generated using the seq_file interface, allowing for efficient
handling of potentially large ITS tables.

This interface is read-only and does not allow modification of the ITS
tables. It is intended for debugging and informational purposes only.

Signed-off-by: Jing Zhang <jingzhangos@google.com>
Link: https://lore.kernel.org/r/20250220224247.2017205-1-jingzhangos@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-05-19 16:10:02 +01:00
Marc Zyngier
201c8d40dd KVM: arm64: nv: Add Maintenance Interrupt emulation
Emulating the vGIC means emulating the dreaded Maintenance Interrupt.

This is a two-pronged problem:

- while running L2, getting an MI translates into an MI injected
  in the L1 based on the state of the HW.

- while running L1, we must accurately reflect the state of the
  MI line, based on the in-memory state.

The MI INTID is added to the distributor, as expected on any
virtualisation-capable implementation, and further patches
will allow its configuration.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20250225172930.1850838-11-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2025-03-03 14:57:10 -08:00
Marc Zyngier
146a050f2d KVM: arm64: nv: Nested GICv3 emulation
When entering a nested VM, we set up the hypervisor control interface
based on what the guest hypervisor has set. Especially, we investigate
each list register written by the guest hypervisor whether HW bit is
set.  If so, we translate hw irq number from the guest's point of view
to the real hardware irq number if there is a mapping.

Co-developed-by: Jintack Lim <jintack@cs.columbia.edu>
Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
[Christoffer: Redesigned execution flow around vcpu load/put]
Co-developed-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
[maz: Rewritten to support GICv3 instead of GICv2, NV2 support]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20250225172930.1850838-9-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2025-03-03 14:57:04 -08:00
Marc Zyngier
3b2c81d5fe KVM: arm64: vgic-its: Add stronger type-checking to the ITS entry sizes
The ITS ABI infrastructure allows for some pretty lax code, where
the size of the data doesn't have to match the size of the entry,
potentially leading to a collection of interesting bugs.

Commit 7fe28d7e68 ("KVM: arm64: vgic-its: Add a data length check
in vgic_its_save_*") added some checks, but starts by implicitly
casting all writes to a 64bit value, hiding some of the issues.

Instead, introduce macros that will check the data type actually used
for dealing with the table entries. The macros are taking a symbolic
entry type that is used to fetch the size of the entry type for the
current ABI. This immediately catches a couple of low-impact gotchas
(zero values that are implicitly 32bit), easy enough to fix.

Given that we currently only have a single ABI, hardcode a couple of
BUILD_BUG_ON()s that will fire if we use anything but a 64bit quantity,
and some (currently unreachable) fallback code that may become useful
one day.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20241117165757.247686-5-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-11-20 17:21:08 -08:00
Marc Zyngier
add570b39f KVM: arm64: vgic: Make vgic_get_irq() more robust
vgic_get_irq() has an awkward signature, as it takes both a kvm
*and* a vcpu, where the vcpu is allowed to be NULL if the INTID
being looked up is a global interrupt (SPI or LPI).

This leads to potentially problematic situations where the INTID
passed is a private interrupt, but that there is no vcpu.

In order to make things less ambiguous, let have *two* helpers
instead:

- vgic_get_irq(struct kvm *kvm, u32 intid), which is only concerned
  with *global* interrupts, as indicated by the lack of vcpu.

- vgic_get_vcpu_irq(struct kvm_vcpu *vcpu, u32 intid), which can
  return *any* interrupt class, but must have of course a non-NULL
  vcpu.

Most of the code nicely falls under one or the other situations,
except for a couple of cases (close to the UABI or in the debug code)
where we have to distinguish between the two cases.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20241117165757.247686-3-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-11-20 17:21:08 -08:00
Jing Zhang
7fe28d7e68 KVM: arm64: vgic-its: Add a data length check in vgic_its_save_*
In all the vgic_its_save_*() functinos, they do not check whether
the data length is 8 bytes before calling vgic_write_guest_lock.
This patch adds the check. To prevent the kernel from being blown up
when the fault occurs, KVM_BUG_ON() is used. And the other BUG_ON()s
are replaced together.

Cc: stable@vger.kernel.org
Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com>
[Jing: Update with the new entry read/write helpers]
Signed-off-by: Jing Zhang <jingzhangos@google.com>
Link: https://lore.kernel.org/r/20241107214137.428439-4-jingzhangos@google.com
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-11-11 19:50:14 +00:00
Marc Zyngier
5cb57a1aff KVM: arm64: Zero ID_AA64PFR0_EL1.GIC when no GICv3 is presented to the guest
In order to be consistent, we shouldn't advertise a GICv3 when none
is actually usable by the guest.

Wipe the feature when these conditions apply, and allow the field
to be written from userspace.

This now allows us to rewrite the kvm_has_gicv3 helper() in terms
of kvm_has_feat(), given that it is always evaluated at runtime.

Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240827152517.3909653-6-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-08-27 18:32:55 +01:00
Marc Zyngier
d2137ba8d8 KVM: arm64: Move GICv3 trap configuration to kvm_calculate_traps()
Follow the pattern introduced with vcpu_set_hcr(), and introduce
vcpu_set_ich_hcr(), which configures the GICv3 traps at the same
point.

This will allow future changes to introduce trap configuration on
a per-VM basis.

Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240827152517.3909653-2-maz@kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-08-27 18:32:55 +01:00
Marc Zyngier
3e6245ebe7 KVM: arm64: Make ICC_*SGI*_EL1 undef in the absence of a vGICv3
On a system with a GICv3, if a guest hasn't been configured with
GICv3 and that the host is not capable of GICv2 emulation,
a write to any of the ICC_*SGI*_EL1 registers is trapped to EL2.

We therefore try to emulate the SGI access, only to hit a NULL
pointer as no private interrupt is allocated (no GIC, remember?).

The obvious fix is to give the guest what it deserves, in the
shape of a UNDEF exception.

Reported-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240820100349.3544850-2-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-08-22 08:08:37 +00:00
Sebastian Ott
19d837bc88 KVM: arm64: vgic: fix unexpected unlock sparse warnings
Get rid of unexpected unlock sparse warnings in vgic code
by adding an annotation to vgic_queue_irq_unlock().

arch/arm64/kvm/vgic/vgic.c:334:17: warning: context imbalance in 'vgic_queue_irq_unlock' - unexpected unlock
arch/arm64/kvm/vgic/vgic.c:419:5: warning: context imbalance in 'kvm_vgic_inject_irq' - different lock contexts for basic block

Signed-off-by: Sebastian Ott <sebott@redhat.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240723101204.7356-4-sebott@redhat.com
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-08-02 18:58:03 +00:00
Marc Zyngier
0d92e4a7ff KVM: arm64: Disassociate vcpus from redistributor region on teardown
When tearing down a redistributor region, make sure we don't have
any dangling pointer to that region stored in a vcpu.

Fixes: e5a3563546 ("kvm: arm64: vgic-v3: Introduce vgic_v3_free_redist_region()")
Reported-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240605175637.1635653-1-maz@kernel.org
Cc: stable@vger.kernel.org
2024-06-06 08:54:15 +01:00
Marc Zyngier
8540bd1b99 Merge branch kvm-arm64/pkvm-6.10 into kvmarm-master/next
* kvm-arm64/pkvm-6.10: (25 commits)
  : .
  : At last, a bunch of pKVM patches, courtesy of Fuad Tabba.
  : From the cover letter:
  :
  : "This series is a bit of a bombay-mix of patches we've been
  : carrying. There's no one overarching theme, but they do improve
  : the code by fixing existing bugs in pKVM, refactoring code to
  : make it more readable and easier to re-use for pKVM, or adding
  : functionality to the existing pKVM code upstream."
  : .
  KVM: arm64: Force injection of a data abort on NISV MMIO exit
  KVM: arm64: Restrict supported capabilities for protected VMs
  KVM: arm64: Refactor setting the return value in kvm_vm_ioctl_enable_cap()
  KVM: arm64: Document the KVM/arm64-specific calls in hypercalls.rst
  KVM: arm64: Rename firmware pseudo-register documentation file
  KVM: arm64: Reformat/beautify PTP hypercall documentation
  KVM: arm64: Clarify rationale for ZCR_EL1 value restored on guest exit
  KVM: arm64: Introduce and use predicates that check for protected VMs
  KVM: arm64: Add is_pkvm_initialized() helper
  KVM: arm64: Simplify vgic-v3 hypercalls
  KVM: arm64: Move setting the page as dirty out of the critical section
  KVM: arm64: Change kvm_handle_mmio_return() return polarity
  KVM: arm64: Fix comment for __pkvm_vcpu_init_traps()
  KVM: arm64: Prevent kmemleak from accessing .hyp.data
  KVM: arm64: Do not map the host fpsimd state to hyp in pKVM
  KVM: arm64: Rename __tlb_switch_to_{guest,host}() in VHE
  KVM: arm64: Support TLB invalidation in guest context
  KVM: arm64: Avoid BBM when changing only s/w bits in Stage-2 PTE
  KVM: arm64: Check for PTE validity when checking for executable/cacheable
  KVM: arm64: Avoid BUG-ing from the host abort path
  ...

Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-05-03 11:39:52 +01:00
Marc Zyngier
948e1a53c2 KVM: arm64: Simplify vgic-v3 hypercalls
Consolidate the GICv3 VMCR accessor hypercalls into the APR save/restore
hypercalls so that all of the EL2 GICv3 state is covered by a single pair
of hypercalls.

Signed-off-by: Fuad Tabba <tabba@google.com>
Acked-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240423150538.2103045-17-tabba@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-05-01 16:48:14 +01:00
Oliver Upton
ec39bbfd55 KVM: arm64: vgic-its: Rip out the global translation cache
The MSI injection fast path has been transitioned away from the global
translation cache. Rip it out.

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240422200158.2606761-12-oliver.upton@linux.dev
Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-04-25 13:19:56 +01:00
Oliver Upton
c09c8ab99a KVM: arm64: vgic-its: Scope translation cache invalidations to an ITS
As the current LPI translation cache is global, the corresponding
invalidation helpers are also globally-scoped. In anticipation of
constructing a translation cache per ITS, add a helper for scoped cache
invalidations.

We still need to support global invalidations when LPIs are toggled on
a redistributor, as a property of the translation cache is that all
stored LPIs are known to be delieverable.

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240422200158.2606761-8-oliver.upton@linux.dev
Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-04-25 13:19:55 +01:00
Oliver Upton
30a0ce9c49 KVM: arm64: vgic-its: Get rid of vgic_copy_lpi_list()
The last user has been transitioned to walking the LPI xarray directly.
Cut the wart off, and get rid of the now unneeded lpi_count while doing
so.

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240422200158.2606761-7-oliver.upton@linux.dev
Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-04-25 13:19:55 +01:00
Oliver Upton
85d3ccc8b7 KVM: arm64: vgic-debug: Use an xarray mark for debug iterator
The vgic debug iterator is the final user of vgic_copy_lpi_list(), but
is a bit more complicated to transition to something else. Use a mark
in the LPI xarray to record the indices 'known' to the debug iterator.
Protect against the LPIs from being freed by associating an additional
reference with the xarray mark.

Rework iter_next() to let the xarray walk 'drive' the iteration after
visiting all of the SGIs, PPIs, and SPIs.

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240422200158.2606761-6-oliver.upton@linux.dev
Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-04-25 13:19:55 +01:00
Oliver Upton
e27f2d561f KVM: arm64: vgic: Don't acquire the lpi_list_lock in vgic_put_irq()
The LPI xarray's xa_lock is sufficient for synchronizing writers when
freeing a given LPI. Furthermore, readers can only take a new reference
on an IRQ if it was already nonzero.

Stop taking the lpi_list_lock unnecessarily and get rid of
__vgic_put_lpi_locked().

Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240221054253.3848076-11-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-23 21:46:02 +00:00
Oliver Upton
864d4304ec KVM: arm64: vgic: Rely on RCU protection in vgic_get_lpi()
Stop acquiring the lpi_list_lock in favor of RCU for protecting
the read-side critical section in vgic_get_lpi(). In order for this to
be safe, we also need to be careful not to take a reference on an irq
with a refcount of 0, as it is about to be freed.

Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240221054253.3848076-9-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-02-23 21:46:02 +00:00
Marc Zyngier
02e3858f08 KVM: arm64: vgic: Force vcpu vgic teardown on vcpu destroy
When failing to create a vcpu because (for example) it has a
duplicate vcpu_id, we destroy the vcpu. Amusingly, this leaves
the redistributor registered with the KVM_MMIO bus.

This is no good, and we should properly clean the mess. Force
a teardown of the vgic vcpu interface, including the RD device
before returning to the caller.

Cc: stable@vger.kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231207151201.3028710-4-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-12-12 07:11:38 +00:00
Yue Haibing
a6b33d009f KVM: arm64: Remove unused declarations
Commit 53692908b0 ("KVM: arm/arm64: vgic: Fix source vcpu issues for GICv2 SGI")
removed vgic_v2_set_npie()/vgic_v3_set_npie() but not the declarations.
Commit 29eb5a3c57 ("KVM: arm64: Handle PtrAuth traps early") left behind
kvm_arm_vcpu_ptrauth_trap(), remove it.
Commit 2a0c343386 ("KVM: arm64: Initialize trap registers for protected VMs")
declared but never implemented kvm_init_protected_traps() and
commit cf5d318865 ("arm/arm64: KVM: Turn off vcpus on PSCI shutdown/reboot")
declared but never implemented force_vm_exit().

Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Reviewed-by: Zenghui Yu <zenghui.yu@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230814140636.45988-1-yuehaibing@huawei.com
2023-08-15 20:27:32 +01:00
Marc Zyngier
96906a9150 KVM: arm64: Expose {un,}lock_all_vcpus() to the rest of KVM
Being able to lock/unlock all vcpus in one go is a feature that
only the vgic has enjoyed so far. Let's be brave and expose it
to the world.

Reviewed-by: Colton Lewis <coltonlewis@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230330174800.2677007-7-maz@kernel.org
2023-03-30 19:01:09 +01:00
Gavin Shan
a23eaf9368 KVM: arm64: Add helper vgic_write_guest_lock()
Currently, the unknown no-running-vcpu sites are reported when a
dirty page is tracked by mark_page_dirty_in_slot(). Until now, the
only known no-running-vcpu site is saving vgic/its tables through
KVM_DEV_ARM_{VGIC_GRP_CTRL, ITS_SAVE_TABLES} command on KVM device
"kvm-arm-vgic-its". Unfortunately, there are more unknown sites to
be handled and no-running-vcpu context will be allowed in these
sites: (1) KVM_DEV_ARM_{VGIC_GRP_CTRL, ITS_RESTORE_TABLES} command
on KVM device "kvm-arm-vgic-its" to restore vgic/its tables. The
vgic3 LPI pending status could be restored. (2) Save vgic3 pending
table through KVM_DEV_ARM_{VGIC_GRP_CTRL, VGIC_SAVE_PENDING_TABLES}
command on KVM device "kvm-arm-vgic-v3".

In order to handle those unknown cases, we need a unified helper
vgic_write_guest_lock(). struct vgic_dist::save_its_tables_in_progress
is also renamed to struct vgic_dist::save_tables_in_progress.

No functional change intended.

Suggested-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230126235451.469087-3-gshan@redhat.com
2023-01-29 18:46:11 +00:00
Marc Zyngier
ef3691683d KVM: arm64: GICv4.1: Fix race with doorbell on VPE activation/deactivation
To save the vgic LPI pending state with GICv4.1, the VPEs must all be
unmapped from the ITSs so that the sGIC caches can be flushed.
The opposite is done once the state is saved.

This is all done by using the activate/deactivate irqdomain callbacks
directly from the vgic code. Crutially, this is done without holding
the irqdesc lock for the interrupts that represent the VPE. And these
callbacks are changing the state of the irqdesc. What could possibly
go wrong?

If a doorbell fires while we are messing with the irqdesc state,
it will acquire the lock and change the interrupt state concurrently.
Since we don't hole the lock, curruption occurs in on the interrupt
state. Oh well.

While acquiring the lock would fix this (and this was Shanker's
initial approach), this is still a layering violation we could do
without. A better approach is actually to free the VPE interrupt,
do what we have to do, and re-request it.

It is more work, but this usually happens only once in the lifetime
of the VM and we don't really care about this sort of overhead.

Fixes: f66b7b151e ("KVM: arm64: GICv4.1: Try to save VLPI state in save_pending_tables")
Reported-by: Shanker Donthineni <sdonthineni@nvidia.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230118022348.4137094-1-sdonthineni@nvidia.com
2023-01-21 11:02:19 +00:00
Marc Zyngier
38cf0bb762 KVM: arm64: vgic-v3: Use u32 to manage the line level from userspace
Despite the userspace ABI clearly defining the bits dealt with by
KVM_DEV_ARM_VGIC_GRP_LEVEL_INFO as a __u32, the kernel uses a u64.

Use a u32 to match the userspace ABI, which will subsequently lead
to some simplifications.

Reviewed-by: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-07-17 11:55:33 +01:00
Marc Zyngier
db25081e14 KVM: arm64: vgic-v3: Push user access into vgic_v3_cpu_sysregs_uaccess()
In order to start making the vgic sysreg access from userspace
similar to all the other sysregs, push the userspace memory
access one level down into vgic_v3_cpu_sysregs_uaccess().

The next step will be to rely on the sysreg infrastructure
to perform this task.

Reviewed-by: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-07-17 11:55:33 +01:00
Marc Zyngier
b61fc0857a KVM: arm64: vgic-v3: Simplify vgic_v3_has_cpu_sysregs_attr()
Finding out whether a sysreg exists has little to do with that
register being accessed, so drop the is_write parameter.

Also, the reg pointer is completely unused, and we're better off
just passing the attr pointer to the function.

This result in a small cleanup of the calling site, with a new
helper converting the vGIC view of a sysreg into the canonical
one (this is purely cosmetic, as the encoding is the same).

Reviewed-by: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-07-17 11:55:33 +01:00
Marc Zyngier
49a1a2c70a KVM: arm64: vgic-v3: Advertise GICR_CTLR.{IR, CES} as a new GICD_IIDR revision
Since adversising GICR_CTLR.{IC,CES} is directly observable from
a guest, we need to make it selectable from userspace.

For that, bump the default GICD_IIDR revision and let userspace
downgrade it to the previous default. For GICv2, the two distributor
revisions are strictly equivalent.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220405182327.205520-5-maz@kernel.org
2022-05-04 14:09:53 +01:00
Marc Zyngier
4645d11f4a KVM: arm64: vgic-v3: Implement MMIO-based LPI invalidation
Since GICv4.1, it has become legal for an implementation to advertise
GICR_{INVLPIR,INVALLR,SYNCR} while having an ITS, allowing for a more
efficient invalidation scheme (no guest command queue contention when
multiple CPUs are generating invalidations).

Provide the invalidation registers as a primitive to their ITS
counterpart. Note that we don't advertise them to the guest yet
(the architecture allows an implementation to do this).

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Oliver Upton <oupton@google.com>
Link: https://lore.kernel.org/r/20220405182327.205520-4-maz@kernel.org
2022-05-04 14:09:53 +01:00
Marc Zyngier
94828468a6 KVM: arm64: vgic-v3: Expose GICR_CTLR.RWP when disabling LPIs
When disabling LPIs, a guest needs to poll GICR_CTLR.RWP in order
to be sure that the write has taken effect. We so far reported it
as 0, as we didn't advertise that LPIs could be turned off the
first place.

Start tracking this state during which LPIs are being disabled,
and expose the 'in progress' state via the RWP bit.

We also take this opportunity to disallow enabling LPIs and programming
GICR_{PEND,PROP}BASER while LPI disabling is in progress, as allowed by
the architecture (UNPRED behaviour).

We don't advertise the feature to the guest yet (which is allowed by
the architecture).

Reviewed-by: Oliver Upton <oupton@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220405182327.205520-3-maz@kernel.org
2022-05-04 14:09:53 +01:00
Ricardo Koller
96e9038969 KVM: arm64: vgic: Drop vgic_check_ioaddr()
There are no more users of vgic_check_ioaddr(). Move its checks to
vgic_check_iorange() and then remove it.

Signed-off-by: Ricardo Koller <ricarkol@google.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211005011921.437353-6-ricarkol@google.com
2021-10-11 09:31:42 +01:00
Ricardo Koller
f25c5e4daf kvm: arm64: vgic: Introduce vgic_check_iorange
Add the new vgic_check_iorange helper that checks that an iorange is
sane: the start address and size have valid alignments, the range is
within the addressable PA range, start+size doesn't overflow, and the
start wasn't already defined.

No functional change.

Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Ricardo Koller <ricarkol@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211005011921.437353-2-ricarkol@google.com
2021-10-11 09:31:41 +01:00
Marc Zyngier
3134cc8beb KVM: arm64: vgic: Resample HW pending state on deactivation
When a mapped level interrupt (a timer, for example) is deactivated
by the guest, the corresponding host interrupt is equally deactivated.
However, the fate of the pending state still needs to be dealt
with in SW.

This is specially true when the interrupt was in the active+pending
state in the virtual distributor at the point where the guest
was entered. On exit, the pending state is potentially stale
(the guest may have put the interrupt in a non-pending state).

If we don't do anything, the interrupt will be spuriously injected
in the guest. Although this shouldn't have any ill effect (spurious
interrupts are always possible), we can improve the emulation by
detecting the deactivation-while-pending case and resample the
interrupt.

While we're at it, move the logic into a common helper that can
be shared between the two GIC implementations.

Fixes: e40cc57bac ("KVM: arm/arm64: vgic: Support level-triggered mapped interrupts")
Reported-by: Raghavendra Rao Ananta <rananta@google.com>
Tested-by: Raghavendra Rao Ananta <rananta@google.com>
Reviewed-by: Oliver Upton <oupton@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210819180305.1670525-1-maz@kernel.org
2021-08-20 08:53:22 +01:00
Marc Zyngier
e629003215 Merge branch 'kvm-arm64/vlpi-save-restore' into kvmarm-master/next
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-04-13 15:41:45 +01:00
Eric Auger
e5a3563546 kvm: arm64: vgic-v3: Introduce vgic_v3_free_redist_region()
To improve the readability, we introduce the new
vgic_v3_free_redist_region helper and also rename
vgic_v3_insert_redist_region into vgic_v3_alloc_redist_region

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210405163941.510258-8-eric.auger@redhat.com
2021-04-06 14:51:38 +01:00
Shenming Lu
80317fe4a6 KVM: arm64: GICv4.1: Add function to get VLPI state
With GICv4.1 and the vPE unmapped, which indicates the invalidation
of any VPT caches associated with the vPE, we can get the VLPI state
by peeking at the VPT. So we add a function for this.

Signed-off-by: Shenming Lu <lushenming@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210322060158.1584-4-lushenming@huawei.com
2021-03-24 18:12:20 +00:00
Linus Torvalds
039aeb9deb ARM:
- Move the arch-specific code into arch/arm64/kvm
 - Start the post-32bit cleanup
 - Cherry-pick a few non-invasive pre-NV patches
 
 x86:
 - Rework of TLB flushing
 - Rework of event injection, especially with respect to nested virtualization
 - Nested AMD event injection facelift, building on the rework of generic code
 and fixing a lot of corner cases
 - Nested AMD live migration support
 - Optimization for TSC deadline MSR writes and IPIs
 - Various cleanups
 - Asynchronous page fault cleanups (from tglx, common topic branch with tip tree)
 - Interrupt-based delivery of asynchronous "page ready" events (host side)
 - Hyper-V MSRs and hypercalls for guest debugging
 - VMX preemption timer fixes
 
 s390:
 - Cleanups
 
 Generic:
 - switch vCPU thread wakeup from swait to rcuwait
 
 The other architectures, and the guest side of the asynchronous page fault
 work, will come next week.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm updates from Paolo Bonzini:
 "ARM:
   - Move the arch-specific code into arch/arm64/kvm

   - Start the post-32bit cleanup

   - Cherry-pick a few non-invasive pre-NV patches

  x86:
   - Rework of TLB flushing

   - Rework of event injection, especially with respect to nested
     virtualization

   - Nested AMD event injection facelift, building on the rework of
     generic code and fixing a lot of corner cases

   - Nested AMD live migration support

   - Optimization for TSC deadline MSR writes and IPIs

   - Various cleanups

   - Asynchronous page fault cleanups (from tglx, common topic branch
     with tip tree)

   - Interrupt-based delivery of asynchronous "page ready" events (host
     side)

   - Hyper-V MSRs and hypercalls for guest debugging

   - VMX preemption timer fixes

  s390:
   - Cleanups

  Generic:
   - switch vCPU thread wakeup from swait to rcuwait

  The other architectures, and the guest side of the asynchronous page
  fault work, will come next week"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (256 commits)
  KVM: selftests: fix rdtsc() for vmx_tsc_adjust_test
  KVM: check userspace_addr for all memslots
  KVM: selftests: update hyperv_cpuid with SynDBG tests
  x86/kvm/hyper-v: Add support for synthetic debugger via hypercalls
  x86/kvm/hyper-v: enable hypercalls regardless of hypercall page
  x86/kvm/hyper-v: Add support for synthetic debugger interface
  x86/hyper-v: Add synthetic debugger definitions
  KVM: selftests: VMX preemption timer migration test
  KVM: nVMX: Fix VMX preemption timer migration
  x86/kvm/hyper-v: Explicitly align hcall param for kvm_hyperv_exit
  KVM: x86/pmu: Support full width counting
  KVM: x86/pmu: Tweak kvm_pmu_get_msr to pass 'struct msr_data' in
  KVM: x86: announce KVM_FEATURE_ASYNC_PF_INT
  KVM: x86: acknowledgment mechanism for async pf page ready notifications
  KVM: x86: interrupt based APF 'page ready' event delivery
  KVM: introduce kvm_read_guest_offset_cached()
  KVM: rename kvm_arch_can_inject_async_page_present() to kvm_arch_can_dequeue_async_page_present()
  KVM: x86: extend struct kvm_vcpu_pv_apf_data with token info
  Revert "KVM: async_pf: Fix #DF due to inject "Page not Present" and "Page Ready" exceptions simultaneously"
  KVM: VMX: Replace zero-length array with flexible-array
  ...
2020-06-03 15:13:47 -07:00
Marc Zyngier
9ed24f4b71 KVM: arm64: Move virt/kvm/arm to arch/arm64
Now that the 32bit KVM/arm host is a distant memory, let's move the
whole of the KVM/arm64 code into the arm64 tree.

As they said in the song: Welcome Home (Sanitarium).

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200513104034.74741-1-maz@kernel.org
2020-05-16 15:03:59 +01:00