Commit graph

28 commits

Author SHA1 Message Date
Marc Zyngier
1b85d923ba Merge branch kvm-arm64/misc-6.16 into kvmarm-master/next
* kvm-arm64/misc-6.16:
  : .
  : Misc changes and improvements for 6.16:
  :
  : - Add a new selftest for the SVE host state being corrupted by a guest
  :
  : - Keep HCR_EL2.xMO set at all times for systems running with the kernel at EL2,
  :   ensuring that the window for interrupts is slightly bigger, and avoiding
  :   a pretty bad erratum on the AmpereOne HW
  :
  : - Replace a couple of open-coded on/off strings with str_on_off()
  :
  : - Get rid of the pKVM memblock sorting, which now appears to be superflous
  :
  : - Drop superflous clearing of ICH_LR_EOI in the LR when nesting
  :
  : - Add workaround for AmpereOne's erratum AC04_CPU_23, which suffers from
  :   a pretty bad case of TLB corruption unless accesses to HCR_EL2 are
  :   heavily synchronised
  :
  : - Add a per-VM, per-ITS debugfs entry to dump the state of the ITS tables
  :   in a human-friendly fashion
  : .
  KVM: arm64: Fix documentation for vgic_its_iter_next()
  KVM: arm64: vgic-its: Add debugfs interface to expose ITS tables
  arm64: errata: Work around AmpereOne's erratum AC04_CPU_23
  KVM: arm64: nv: Remove clearing of ICH_LR<n>.EOI if ICH_LR<n>.HW == 1
  KVM: arm64: Drop sort_memblock_regions()
  KVM: arm64: selftests: Add test for SVE host corruption
  KVM: arm64: Force HCR_EL2.xMO to 1 at all times in VHE mode
  KVM: arm64: Replace ternary flags with str_on_off() helper

Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-05-23 10:59:43 +01:00
Vincent Donnefort
db14091d8f KVM: arm64: Stage-2 huge mappings for np-guests
Now np-guests hypercalls with range are supported, we can let the
hypervisor to install block mappings whenever the Stage-1 allows it,
that is when backed by either Hugetlbfs or THPs. The size of those block
mappings is limited to PMD_SIZE.

Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/r/20250521124834.1070650-10-vdonnefort@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-05-21 14:33:51 +01:00
Quentin Perret
3669ddd8fa KVM: arm64: Add a range to pkvm_mappings
In preparation for supporting stage-2 huge mappings for np-guest, add a
nr_pages member for pkvm_mappings to allow EL1 to track the size of the
stage-2 mapping.

Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/r/20250521124834.1070650-9-vdonnefort@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-05-21 14:33:51 +01:00
Quentin Perret
b38c9775f7 KVM: arm64: Convert pkvm_mappings to interval tree
In preparation for supporting stage-2 huge mappings for np-guest, let's
convert pgt.pkvm_mappings to an interval tree.

No functional change intended.

Suggested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/r/20250521124834.1070650-8-vdonnefort@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-05-21 14:33:51 +01:00
Vincent Donnefort
c4d99a833d KVM: arm64: Add a range to __pkvm_host_test_clear_young_guest()
In preparation for supporting stage-2 huge mappings for np-guest. Add a
nr_pages argument to the __pkvm_host_test_clear_young_guest hypercall.
This range supports only two values: 1 or PMD_SIZE / PAGE_SIZE (that is
512 on a 4K-pages system).

Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/r/20250521124834.1070650-7-vdonnefort@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-05-21 14:33:51 +01:00
Vincent Donnefort
0eb802b3b4 KVM: arm64: Add a range to __pkvm_host_wrprotect_guest()
In preparation for supporting stage-2 huge mappings for np-guest. Add a
nr_pages argument to the __pkvm_host_wrprotect_guest hypercall. This
range supports only two values: 1 or PMD_SIZE / PAGE_SIZE (that is 512
on a 4K-pages system).

Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/r/20250521124834.1070650-6-vdonnefort@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-05-21 14:33:51 +01:00
Vincent Donnefort
f28f1d02f4 KVM: arm64: Add a range to __pkvm_host_unshare_guest()
In preparation for supporting stage-2 huge mappings for np-guest. Add a
nr_pages argument to the __pkvm_host_unshare_guest hypercall. This range
supports only two values: 1 or PMD_SIZE / PAGE_SIZE (that is 512 on a
4K-pages system).

Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/r/20250521124834.1070650-5-vdonnefort@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-05-21 14:33:51 +01:00
Vincent Donnefort
4274385ebf KVM: arm64: Add a range to __pkvm_host_share_guest()
In preparation for supporting stage-2 huge mappings for np-guest. Add a
nr_pages argument to the __pkvm_host_share_guest hypercall. This range
supports only two values: 1 or PMD_SIZE / PAGE_SIZE (that is 512 on a
4K-pages system).

Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/r/20250521124834.1070650-4-vdonnefort@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-05-21 14:33:51 +01:00
Gavin Shan
00b0300cf1 KVM: arm64: Drop sort_memblock_regions()
Drop sort_memblock_regions() and avoid sorting the copied memory
regions to be ascending order on their base addresses, because the
source memory regions should have been sorted correctly when they
are added by memblock_add() or its variants.

This is generally reverting commit a14307f531 ("KVM: arm64: Sort
the hypervisor memblocks"). No functional changes intended.

Signed-off-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Quentin Perret <qperret@google.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20250311043718.91004-1-gshan@redhat.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-05-08 11:29:45 +01:00
Quentin Perret
48d5645072 KVM: arm64: Extend pKVM selftest for np-guests
The pKVM selftest intends to test as many memory 'transitions' as
possible, so extend it to cover sharing pages with non-protected guests,
including in the case of multi-sharing.

Signed-off-by: Quentin Perret <qperret@google.com>
Link: https://lore.kernel.org/r/20250416160900.3078417-5-qperret@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-05-06 09:56:18 +01:00
David Brazdil
74b13d5816 KVM: arm64: Add .hyp.data section
The hypervisor has not needed its own .data section because all globals
were either .rodata or .bss. To avoid having to initialize future
data-structures at run-time, let's introduce add a .data section to the
hypervisor.

Signed-off-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Link: https://lore.kernel.org/r/20250416160900.3078417-2-qperret@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-05-06 09:56:18 +01:00
Fuad Tabba
1eab115486 KVM: arm64: Create each pKVM hyp vcpu after its corresponding host vcpu
Instead of creating and initializing _all_ hyp vcpus in pKVM when
the first host vcpu runs for the first time, initialize _each_
hyp vcpu in conjunction with its corresponding host vcpu.

Some of the host vcpu state (e.g., system registers and traps
values) is not initialized until the first time the host vcpu is
run. Therefore, initializing a hyp vcpu before its corresponding
host vcpu has run for the first time might not view the complete
host state of these vcpus.

Additionally, this behavior is inline with non-protected modes.

Acked-by: Will Deacon <will@kernel.org>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20250314111832.4137161-5-tabba@google.com
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2025-03-14 16:06:03 -07:00
Fuad Tabba
8b21fb47c7 KVM: arm64: Factor out pKVM hyp vcpu creation to separate function
Move the code that creates and initializes the hyp view of a vcpu
in pKVM to its own function. This is meant to make the transition
to initializing every vcpu individually clearer.

Acked-by: Will Deacon <will@kernel.org>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20250314111832.4137161-4-tabba@google.com
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2025-03-14 16:04:23 -07:00
Vincent Donnefort
79ea662315 KVM: arm64: Count pKVM stage-2 usage in secondary pagetable stats
Count the pages used by pKVM for the guest stage-2 in memory stats under
secondary pagetable, similarly to what the VHE mode does.

Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20250313114038.1502357-4-vdonnefort@google.com
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2025-03-14 00:56:30 -07:00
Vincent Donnefort
8c0d7d14c5 KVM: arm64: Distinct pKVM teardown memcache for stage-2
In order to account for memory dedicated to the stage-2 page-tables, use
a separated memcache when tearing down the VM. Meanwhile rename
reclaim_guest_pages to reflect the fact it only reclaim page-table
pages.

Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20250313114038.1502357-3-vdonnefort@google.com
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2025-03-14 00:56:29 -07:00
Quentin Perret
e912efed48 KVM: arm64: Introduce the EL1 pKVM MMU
Introduce a set of helper functions allowing to manipulate the pKVM
guest stage-2 page-tables from EL1 using pKVM's HVC interface.

Each helper has an exact one-to-one correspondance with the traditional
kvm_pgtable_stage2_*() functions from pgtable.c, with a strictly
matching prototype. This will ease plumbing later on in mmu.c.

These callbacks track the gfn->pfn mappings in a simple rb_tree indexed
by IPA in lieu of a page-table. This rb-tree is kept in sync with pKVM's
state and is protected by the mmu_lock like a traditional stage-2
page-table.

Signed-off-by: Quentin Perret <qperret@google.com>
Tested-by: Fuad Tabba <tabba@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Link: https://lore.kernel.org/r/20241218194059.3670226-18-qperret@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-12-20 09:44:00 +00:00
Quentin Perret
06cacc9d28 KVM: arm64: Prevent kmemleak from accessing .hyp.data
We've added a .data section for the hypervisor, which kmemleak is
eager to parse. This clearly doesn't go well, so add the section
to kmemleak's block list.

Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Fuad Tabba <tabba@google.com>
Acked-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240423150538.2103045-13-tabba@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-05-01 16:48:14 +01:00
Fuad Tabba
40099dedb4 KVM: arm64: Do not re-initialize the KVM lock
The lock is already initialized in core KVM code at
kvm_create_vm().

Fixes: 9d0c063a4d ("KVM: arm64: Instantiate pKVM hypervisor VM and vCPU structures from EL1")
Signed-off-by: Fuad Tabba <tabba@google.com>
Acked-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240423150538.2103045-5-tabba@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2024-05-01 16:46:58 +01:00
Sebastian Ene
10c02aad11 KVM: arm64: Fix circular locking dependency
The rule inside kvm enforces that the vcpu->mutex is taken *inside*
kvm->lock. The rule is violated by the pkvm_create_hyp_vm() which acquires
the kvm->lock while already holding the vcpu->mutex lock from
kvm_vcpu_ioctl(). Avoid the circular locking dependency altogether by
protecting the hyp vm handle with the config_lock, much like we already
do for other forms of VM-scoped data.

Signed-off-by: Sebastian Ene <sebastianene@google.com>
Cc: stable@vger.kernel.org
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240124091027.1477174-2-sebastianene@google.com
2024-01-30 21:30:33 +00:00
Marc Zyngier
fe49fd940e KVM: arm64: Move VTCR_EL2 into struct s2_mmu
We currently have a global VTCR_EL2 value for each guest, even
if the guest uses NV. This implies that the guest's own S2 must
fit in the host's. This is odd, for multiple reasons:

- the PARange values and the number of IPA bits don't necessarily
  match: you can have 33 bits of IPA space, and yet you can only
  describe 32 or 36 bits of PARange

- When userspace set the IPA space, it creates a contract with the
  kernel saying "this is the IPA space I'm prepared to handle".
  At no point does it constraint the guest's own IPA space as
  long as the guest doesn't try to use a [I]PA outside of the
  IPA space set by userspace

- We don't even try to hide the value of ID_AA64MMFR0_EL1.PARange.

And then there is the consequence of the above: if a guest tries
to create a S2 that has for input address something that is larger
than the IPA space defined by the host, we inject a fatal exception.

This is no good. For all intent and purposes, a guest should be
able to have the S2 it really wants, as long as the *output* address
of that S2 isn't outside of the IPA space.

For that, we need to have a per-s2_mmu VTCR_EL2 setting, which
allows us to represent the full PARange. Move the vctr field into
the s2_mmu structure, which has no impact whatsoever, except for NV.

Note that once we are able to override ID_AA64MMFR0_EL1.PARange
from userspace, we'll also be able to restrict the size of the
shadow S2 that NV uses.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20231012205108.3937270-1-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-10-23 18:48:46 +00:00
Sudeep Holla
fa729bc7c9 KVM: arm64: Handle kvm_arm_init failure correctly in finalize_pkvm
Currently there is no synchronisation between finalize_pkvm() and
kvm_arm_init() initcalls. The finalize_pkvm() proceeds happily even if
kvm_arm_init() fails resulting in the following warning on all the CPUs
and eventually a HYP panic:

  | kvm [1]: IPA Size Limit: 48 bits
  | kvm [1]: Failed to init hyp memory protection
  | kvm [1]: error initializing Hyp mode: -22
  |
  | <snip>
  |
  | WARNING: CPU: 0 PID: 0 at arch/arm64/kvm/pkvm.c:226 _kvm_host_prot_finalize+0x30/0x50
  | Modules linked in:
  | CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.4.0 #237
  | Hardware name: FVP Base RevC (DT)
  | pstate: 634020c5 (nZCv daIF +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
  | pc : _kvm_host_prot_finalize+0x30/0x50
  | lr : __flush_smp_call_function_queue+0xd8/0x230
  |
  | Call trace:
  |  _kvm_host_prot_finalize+0x3c/0x50
  |  on_each_cpu_cond_mask+0x3c/0x6c
  |  pkvm_drop_host_privileges+0x4c/0x78
  |  finalize_pkvm+0x3c/0x5c
  |  do_one_initcall+0xcc/0x240
  |  do_initcall_level+0x8c/0xac
  |  do_initcalls+0x54/0x94
  |  do_basic_setup+0x1c/0x28
  |  kernel_init_freeable+0x100/0x16c
  |  kernel_init+0x20/0x1a0
  |  ret_from_fork+0x10/0x20
  | Failed to finalize Hyp protection: -22
  |     dtb=fvp-base-revc.dtb
  | kvm [95]: nVHE hyp BUG at: arch/arm64/kvm/hyp/nvhe/mem_protect.c:540!
  | kvm [95]: nVHE call trace:
  | kvm [95]:  [<ffff800081052984>] __kvm_nvhe_hyp_panic+0xac/0xf8
  | kvm [95]:  [<ffff800081059644>] __kvm_nvhe_handle_host_mem_abort+0x1a0/0x2ac
  | kvm [95]:  [<ffff80008105511c>] __kvm_nvhe_handle_trap+0x4c/0x160
  | kvm [95]:  [<ffff8000810540fc>] __kvm_nvhe___skip_pauth_save+0x4/0x4
  | kvm [95]: ---[ end nVHE call trace ]---
  | kvm [95]: Hyp Offset: 0xfffe8db00ffa0000
  | Kernel panic - not syncing: HYP panic:
  | PS:a34023c9 PC:0000f250710b973c ESR:00000000f2000800
  | FAR:ffff000800cb00d0 HPFAR:000000000880cb00 PAR:0000000000000000
  | VCPU:0000000000000000
  | CPU: 3 PID: 95 Comm: kworker/u16:2 Tainted: G        W          6.4.0 #237
  | Hardware name: FVP Base RevC (DT)
  | Workqueue: rpciod rpc_async_schedule
  | Call trace:
  |  dump_backtrace+0xec/0x108
  |  show_stack+0x18/0x2c
  |  dump_stack_lvl+0x50/0x68
  |  dump_stack+0x18/0x24
  |  panic+0x138/0x33c
  |  nvhe_hyp_panic_handler+0x100/0x184
  |  new_slab+0x23c/0x54c
  |  ___slab_alloc+0x3e4/0x770
  |  kmem_cache_alloc_node+0x1f0/0x278
  |  __alloc_skb+0xdc/0x294
  |  tcp_stream_alloc_skb+0x2c/0xf0
  |  tcp_sendmsg_locked+0x3d0/0xda4
  |  tcp_sendmsg+0x38/0x5c
  |  inet_sendmsg+0x44/0x60
  |  sock_sendmsg+0x1c/0x34
  |  xprt_sock_sendmsg+0xdc/0x274
  |  xs_tcp_send_request+0x1ac/0x28c
  |  xprt_transmit+0xcc/0x300
  |  call_transmit+0x78/0x90
  |  __rpc_execute+0x114/0x3d8
  |  rpc_async_schedule+0x28/0x48
  |  process_one_work+0x1d8/0x314
  |  worker_thread+0x248/0x474
  |  kthread+0xfc/0x184
  |  ret_from_fork+0x10/0x20
  | SMP: stopping secondary CPUs
  | Kernel Offset: 0x57c5cb460000 from 0xffff800080000000
  | PHYS_OFFSET: 0x80000000
  | CPU features: 0x00000000,1035b7a3,ccfe773f
  | Memory Limit: none
  | ---[ end Kernel panic - not syncing: HYP panic:
  | PS:a34023c9 PC:0000f250710b973c ESR:00000000f2000800
  | FAR:ffff000800cb00d0 HPFAR:000000000880cb00 PAR:0000000000000000
  | VCPU:0000000000000000 ]---

Fix it by checking for the successfull initialisation of kvm_arm_init()
in finalize_pkvm() before proceeding any futher.

Fixes: 87727ba2bb ("KVM: arm64: Ensure CPU PMU probes before pKVM host de-privilege")
Cc: Will Deacon <will@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: James Morse <james.morse@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230704193243.3300506-1-sudeep.holla@arm.com
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-07-11 19:30:14 +00:00
Will Deacon
bc3888a0f4 KVM: arm64: Allocate pages for hypervisor FF-A mailboxes
The FF-A proxy code needs to allocate its own buffer pair for
communication with EL3 and for forwarding calls from the host at EL1.

Reserve a couple of pages for this purpose and use them to initialise
the hypervisor's FF-A buffer structure.

Co-developed-by: Andrew Walbran <qwandor@google.com>
Signed-off-by: Andrew Walbran <qwandor@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20230523101828.7328-4-will@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2023-06-01 21:34:50 +00:00
Will Deacon
87727ba2bb KVM: arm64: Ensure CPU PMU probes before pKVM host de-privilege
Although pKVM supports CPU PMU emulation for non-protected guests since
722625c6f4 ("KVM: arm64: Reenable pmu in Protected Mode"), this relies
on the PMU driver probing before the host has de-privileged so that the
'kvm_arm_pmu_available' static key can still be enabled by patching the
hypervisor text.

As it happens, both of these events hang off device_initcall() but the
PMU consistently won the race until 7755cec63a ("arm64: perf: Move
PMUv3 driver to drivers/perf"). Since then, the host will fail to boot
when pKVM is enabled:

  | hw perfevents: enabled with armv8_pmuv3_0 PMU driver, 7 counters available
  | kvm [1]: nVHE hyp BUG at: [<ffff8000090366e0>] __kvm_nvhe_handle_host_mem_abort+0x270/0x284!
  | kvm [1]: Cannot dump pKVM nVHE stacktrace: !CONFIG_PROTECTED_NVHE_STACKTRACE
  | kvm [1]: Hyp Offset: 0xfffea41fbdf70000
  | Kernel panic - not syncing: HYP panic:
  | PS:a00003c9 PC:0000dbe04b0c66e0 ESR:00000000f2000800
  | FAR:fffffbfffddfcf00 HPFAR:00000000010b0bf0 PAR:0000000000000000
  | VCPU:0000000000000000
  | CPU: 2 PID: 1 Comm: swapper/0 Not tainted 6.3.0-rc7-00083-g0bce6746d154 #1
  | Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015
  | Call trace:
  |  dump_backtrace+0xec/0x108
  |  show_stack+0x18/0x2c
  |  dump_stack_lvl+0x50/0x68
  |  dump_stack+0x18/0x24
  |  panic+0x13c/0x33c
  |  nvhe_hyp_panic_handler+0x10c/0x190
  |  aarch64_insn_patch_text_nosync+0x64/0xc8
  |  arch_jump_label_transform+0x4c/0x5c
  |  __jump_label_update+0x84/0xfc
  |  jump_label_update+0x100/0x134
  |  static_key_enable_cpuslocked+0x68/0xac
  |  static_key_enable+0x20/0x34
  |  kvm_host_pmu_init+0x88/0xa4
  |  armpmu_register+0xf0/0xf4
  |  arm_pmu_acpi_probe+0x2ec/0x368
  |  armv8_pmu_driver_init+0x38/0x44
  |  do_one_initcall+0xcc/0x240

Fix the race properly by deferring the de-privilege step to
device_initcall_sync(). This will also be needed in future when probing
IOMMU devices and allows us to separate the pKVM de-privilege logic from
the core hypervisor initialisation path.

Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Fuad Tabba <tabba@google.com>
Cc: Marc Zyngier <maz@kernel.org>
Fixes: 7755cec63a ("arm64: perf: Move PMUv3 driver to drivers/perf")
Tested-by: Fuad Tabba <tabba@google.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230420123356.2708-1-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2023-04-20 16:57:53 +01:00
Quentin Perret
f41dff4efb KVM: arm64: Return guest memory from EL2 via dedicated teardown memcache
Rather than relying on the host to free the previously-donated pKVM
hypervisor VM pages explicitly on teardown, introduce a dedicated
teardown memcache which allows the host to reclaim guest memory
resources without having to keep track of all of the allocations made by
the pKVM hypervisor at EL2.

Tested-by: Vincent Donnefort <vdonnefort@google.com>
Co-developed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
[maz: dropped __maybe_unused from unmap_donated_memory_noclear()]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-21-will@kernel.org
2022-11-11 17:18:58 +00:00
Fuad Tabba
9d0c063a4d KVM: arm64: Instantiate pKVM hypervisor VM and vCPU structures from EL1
With the pKVM hypervisor at EL2 now offering hypercalls to the host for
creating and destroying VM and vCPU structures, plumb these in to the
existing arm64 KVM backend to ensure that the hypervisor data structures
are allocated and initialised on first vCPU run for a pKVM guest.

In the host, 'struct kvm_protected_vm' is introduced to hold the handle
of the pKVM VM instance as well as to track references to the memory
donated to the hypervisor so that it can be freed back to the host
allocator following VM teardown. The stage-2 page-table, hypervisor VM
and vCPU structures are allocated separately so as to avoid the need for
a large physically-contiguous allocation in the host at run-time.

Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-14-will@kernel.org
2022-11-11 17:16:24 +00:00
Fuad Tabba
a1ec5c70d3 KVM: arm64: Add infrastructure to create and track pKVM instances at EL2
Introduce a global table (and lock) to track pKVM instances at EL2, and
provide hypercalls that can be used by the untrusted host to create and
destroy pKVM VMs and their vCPUs. pKVM VM/vCPU state is directly
accessible only by the trusted hypervisor (EL2).

Each pKVM VM is directly associated with an untrusted host KVM instance,
and is referenced by the host using an opaque handle. Future patches
will provide hypercalls to allow the host to initialize/set/get pKVM
VM/vCPU state using the opaque handle.

Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Fuad Tabba <tabba@google.com>
Co-developed-by: Will Deacon <will@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
[maz: silence warning on unmap_donated_memory_noclear()]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-13-will@kernel.org
2022-11-11 17:16:05 +00:00
Quentin Perret
8e6bcc3a45 KVM: arm64: Back the hypervisor 'struct hyp_page' array for all memory
The EL2 'vmemmap' array in nVHE Protected mode is currently very sparse:
only memory pages owned by the hypervisor itself have a matching 'struct
hyp_page'. However, as the size of this struct has been reduced
significantly since its introduction, it appears that we can now afford
to back the vmemmap for all of memory.

Having an easily accessible 'struct hyp_page' for every physical page in
memory provides the hypervisor with a simple mechanism to store metadata
(e.g. a refcount) that wouldn't otherwise fit in the very limited number
of software bits available in the host stage-2 page-table entries. This
will be used in subsequent patches when pinning host memory pages for
use by the hypervisor at EL2.

Tested-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221110190259.26861-4-will@kernel.org
2022-11-11 16:40:54 +00:00
Will Deacon
9429f4b041 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 <will@kernel.org>
Tested-by: Fuad Tabba <tabba@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211202171048.26924-4-will@kernel.org
2021-12-06 08:37:03 +00:00
Renamed from arch/arm64/kvm/hyp/reserved_mem.c (Browse further)