871 Commits

Author SHA1 Message Date
Marc Zyngier
d96ef8fa95 KVM: arm64: Save the host's PtrAuth keys in non-preemptible context
commit ef3e40a7ea8dbe2abd0a345032cd7d5023b9684f upstream.

When using the PtrAuth feature in a guest, we need to save the host's
keys before allowing the guest to program them. For that, we dump
them in a per-CPU data structure (the so called host context).

But both call sites that do this are in preemptible context,
which may end up in disaster should the vcpu thread get preempted
before reentering the guest.

Instead, save the keys eagerly on each vcpu_load(). This has an
increased overhead, but is at least safe.

Cc: stable@vger.kernel.org
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-17 16:40:38 +02:00
Marc Zyngier
8128576788 KVM: arm64: Synchronize sysreg state on injecting an AArch32 exception
commit 0370964dd3ff7d3d406f292cb443a927952cbd05 upstream.

On a VHE system, the EL1 state is left in the CPU most of the time,
and only syncronized back to memory when vcpu_put() is called (most
of the time on preemption).

Which means that when injecting an exception, we'd better have a way
to either:
(1) write directly to the EL1 sysregs
(2) synchronize the state back to memory, and do the changes there

For an AArch64, we already do (1), so we are safe. Unfortunately,
doing the same thing for AArch32 would be pretty invasive. Instead,
we can easily implement (2) by calling the put/load architectural
backends, and keep preemption disabled. We can then reload the
state back into EL1.

Cc: stable@vger.kernel.org
Reported-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-17 16:40:38 +02:00
Marc Zyngier
163b489325 KVM: arm: vgic: Synchronize the whole guest on GIC{D,R}_I{S,C}ACTIVER read
[ Upstream commit 9a50ebbffa9862db7604345f5fd763122b0f6fed ]

When a guest tries to read the active state of its interrupts,
we currently just return whatever state we have in memory. This
means that if such an interrupt lives in a List Register on another
CPU, we fail to obsertve the latest active state for this interrupt.

In order to remedy this, stop all the other vcpus so that they exit
and we can observe the most recent value for the state. This is
similar to what we are doing for the write side of the same
registers, and results in new MMIO handlers for userspace (which
do not need to stop the guest, as it is supposed to be stopped
already).

Reported-by: Julien Grall <julien@xen.org>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-20 08:20:04 +02:00
Marc Zyngier
e983c6064a KVM: arm64: Fix 32bit PC wrap-around
commit 0225fd5e0a6a32af7af0aefac45c8ebf19dc5183 upstream.

In the unlikely event that a 32bit vcpu traps into the hypervisor
on an instruction that is located right at the end of the 32bit
range, the emulation of that instruction is going to increment
PC past the 32bit range. This isn't great, as userspace can then
observe this value and get a bit confused.

Conversly, userspace can do things like (in the context of a 64bit
guest that is capable of 32bit EL0) setting PSTATE to AArch64-EL0,
set PC to a 64bit value, change PSTATE to AArch32-USR, and observe
that PC hasn't been truncated. More confusion.

Fix both by:
- truncating PC increments for 32bit guests
- sanitizing all 32bit regs every time a core reg is changed by
  userspace, and that PSTATE indicates a 32bit mode.

Cc: stable@vger.kernel.org
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14 07:58:26 +02:00
Marc Zyngier
3ae9279d72 KVM: arm: vgic: Fix limit condition when writing to GICD_I[CS]ACTIVER
commit 1c32ca5dc6d00012f0c964e5fdd7042fcc71efb1 upstream.

When deciding whether a guest has to be stopped we check whether this
is a private interrupt or not. Unfortunately, there's an off-by-one bug
here, and we fail to recognize a whole range of interrupts as being
global (GICv2 SPIs 32-63).

Fix the condition from > to be >=.

Cc: stable@vger.kernel.org
Fixes: abd7229626b93 ("KVM: arm/arm64: Simplify active_change_prepare and plug race")
Reported-by: André Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-14 07:58:25 +02:00
Alexandru Elisei
0ec337059d KVM: arm64: Treat emulated TVAL TimerValue as a signed 32-bit integer
commit 4a267aa707953a9a73d1f5dc7f894dd9024a92be upstream.

According to the ARM ARM, registers CNT{P,V}_TVAL_EL0 have bits [63:32]
RES0 [1]. When reading the register, the value is truncated to the least
significant 32 bits [2], and on writes, TimerValue is treated as a signed
32-bit integer [1, 2].

When the guest behaves correctly and writes 32-bit values, treating TVAL
as an unsigned 64 bit register works as expected. However, things start
to break down when the guest writes larger values, because
(u64)0x1_ffff_ffff = 8589934591. but (s32)0x1_ffff_ffff = -1, and the
former will cause the timer interrupt to be asserted in the future, but
the latter will cause it to be asserted now.  Let's treat TVAL as a
signed 32-bit register on writes, to match the behaviour described in
the architecture, and the behaviour experimentally exhibited by the
virtual timer on a non-vhe host.

[1] Arm DDI 0487E.a, section D13.8.18
[2] Arm DDI 0487E.a, section D11.2.4

Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
[maz: replaced the read-side mask with lower_32_bits]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Fixes: 8fa761624871 ("KVM: arm/arm64: arch_timer: Fix CNTP_TVAL calculation")
Link: https://lore.kernel.org/r/20200127103652.2326-1-alexandru.elisei@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:34:18 -05:00
Eric Auger
a17d216404 KVM: arm64: pmu: Fix chained SW_INCR counters
commit aa76829171e98bd75a0cc00b6248eca269ac7f4f upstream.

At the moment a SW_INCR counter always overflows on 32-bit
boundary, independently on whether the n+1th counter is
programmed as CHAIN.

Check whether the SW_INCR counter is a 64b counter and if so,
implement the 64b logic.

Fixes: 80f393a23be6 ("KVM: arm/arm64: Support chained PMU counters")
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200124142535.29386-4-eric.auger@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:34:17 -05:00
Eric Auger
a6229d1b5c KVM: arm64: pmu: Don't increment SW_INCR if PMCR.E is unset
commit 3837407c1aa1101ed5e214c7d6041e7a23335c6e upstream.

The specification says PMSWINC increments PMEVCNTR<n>_EL1 by 1
if PMEVCNTR<n>_EL0 is enabled and configured to count SW_INCR.

For PMEVCNTR<n>_EL0 to be enabled, we need both PMCNTENSET to
be set for the corresponding event counter but we also need
the PMCR.E bit to be set.

Fixes: 7a0adc7064b8 ("arm64: KVM: Add access handler for PMSWINC register")
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Andrew Murray <andrew.murray@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200124142535.29386-2-eric.auger@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:34:17 -05:00
James Morse
93a509cf11 KVM: arm: Make inject_abt32() inject an external abort instead
commit 21aecdbd7f3ab02c9b82597dc733ee759fb8b274 upstream.

KVM's inject_abt64() injects an external-abort into an aarch64 guest.
The KVM_CAP_ARM_INJECT_EXT_DABT is intended to do exactly this, but
for an aarch32 guest inject_abt32() injects an implementation-defined
exception, 'Lockdown fault'.

Change this to external abort. For non-LPAE we now get the documented:
| Unhandled fault: external abort on non-linefetch (0x008) at 0x9c800f00
and for LPAE:
| Unhandled fault: synchronous external abort (0x210) at 0x9c800f00

Fixes: 74a64a981662a ("KVM: arm/arm64: Unify 32bit fault injection")
Reported-by: Beata Michalska <beata.michalska@linaro.org>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200121123356.203000-3-james.morse@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:34:17 -05:00
James Morse
9cce31930a KVM: arm: Fix DFSR setting for non-LPAE aarch32 guests
commit 018f22f95e8a6c3e27188b7317ef2c70a34cb2cd upstream.

Beata reports that KVM_SET_VCPU_EVENTS doesn't inject the expected
exception to a non-LPAE aarch32 guest.

The host intends to inject DFSR.FS=0x14 "IMPLEMENTATION DEFINED fault
(Lockdown fault)", but the guest receives DFSR.FS=0x04 "Fault on
instruction cache maintenance". This fault is hooked by
do_translation_fault() since ARMv6, which goes on to silently 'handle'
the exception, and restart the faulting instruction.

It turns out, when TTBCR.EAE is clear DFSR is split, and FS[4] has
to shuffle up to DFSR[10].

As KVM only does this in one place, fix up the static values. We
now get the expected:
| Unhandled fault: lock abort (0x404) at 0x9c800f00

Fixes: 74a64a981662a ("KVM: arm/arm64: Unify 32bit fault injection")
Reported-by: Beata Michalska <beata.michalska@linaro.org>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200121123356.203000-2-james.morse@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:34:17 -05:00
Gavin Shan
48f9ec2020 KVM: arm/arm64: Fix young bit from mmu notifier
commit cf2d23e0bac9f6b5cd1cba8898f5f05ead40e530 upstream.

kvm_test_age_hva() is called upon mmu_notifier_test_young(), but wrong
address range has been passed to handle_hva_to_gpa(). With the wrong
address range, no young bits will be checked in handle_hva_to_gpa().
It means zero is always returned from mmu_notifier_test_young().

This fixes the issue by passing correct address range to the underly
function handle_hva_to_gpa(), so that the hardware young (access) bit
will be visited.

Fixes: 35307b9a5f7e ("arm/arm64: KVM: Implement Stage-2 page aging")
Signed-off-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200121055659.19560-1-gshan@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:34:17 -05:00
Eric Auger
199808393e KVM: arm/arm64: vgic-its: Fix restoration of unmapped collections
commit 8c58be34494b7f1b2adb446e2d8beeb90e5de65b upstream.

Saving/restoring an unmapped collection is a valid scenario. For
example this happens if a MAPTI command was sent, featuring an
unmapped collection. At the moment the CTE fails to be restored.
Only compare against the number of online vcpus if the rdist
base is set.

Fixes: ea1ad53e1e31a ("KVM: arm64: vgic-its: Collection table save/restore")
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20191213094237.19627-1-eric.auger@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-14 16:34:17 -05:00
Christoffer Dall
6cca9100db KVM: arm64: Only sign-extend MMIO up to register width
commit b6ae256afd32f96bec0117175b329d0dd617655e upstream.

On AArch64 you can do a sign-extended load to either a 32-bit or 64-bit
register, and we should only sign extend the register up to the width of
the register as specified in the operation (by using the 32-bit Wn or
64-bit Xn register specifier).

As it turns out, the architecture provides this decoding information in
the SF ("Sixty-Four" -- how cute...) bit.

Let's take advantage of this with the usual 32-bit/64-bit header file
dance and do the right thing on AArch64 hosts.

Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20191212195055.5541-1-christoffer.dall@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:35:16 -08:00
Mark Rutland
4dd5c62d2e KVM: arm/arm64: Correct AArch32 SPSR on exception entry
commit 1cfbb484de158e378e8971ac40f3082e53ecca55 upstream.

Confusingly, there are three SPSR layouts that a kernel may need to deal
with:

(1) An AArch64 SPSR_ELx view of an AArch64 pstate
(2) An AArch64 SPSR_ELx view of an AArch32 pstate
(3) An AArch32 SPSR_* view of an AArch32 pstate

When the KVM AArch32 support code deals with SPSR_{EL2,HYP}, it's either
dealing with #2 or #3 consistently. On arm64 the PSR_AA32_* definitions
match the AArch64 SPSR_ELx view, and on arm the PSR_AA32_* definitions
match the AArch32 SPSR_* view.

However, when we inject an exception into an AArch32 guest, we have to
synthesize the AArch32 SPSR_* that the guest will see. Thus, an AArch64
host needs to synthesize layout #3 from layout #2.

This patch adds a new host_spsr_to_spsr32() helper for this, and makes
use of it in the KVM AArch32 support code. For arm64 we need to shuffle
the DIT bit around, and remove the SS bit, while for arm we can use the
value as-is.

I've open-coded the bit manipulation for now to avoid having to rework
the existing PSR_* definitions into PSR64_AA32_* and PSR32_AA32_*
definitions. I hope to perform a more thorough refactoring in future so
that we can handle pstate view manipulation more consistently across the
kernel tree.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200108134324.46500-4-mark.rutland@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:35:16 -08:00
Mark Rutland
b0e01e9d23 KVM: arm/arm64: Correct CPSR on exception entry
commit 3c2483f15499b877ccb53250d88addb8c91da147 upstream.

When KVM injects an exception into a guest, it generates the CPSR value
from scratch, configuring CPSR.{M,A,I,T,E}, and setting all other
bits to zero.

This isn't correct, as the architecture specifies that some CPSR bits
are (conditionally) cleared or set upon an exception, and others are
unchanged from the original context.

This patch adds logic to match the architectural behaviour. To make this
simple to follow/audit/extend, documentation references are provided,
and bits are configured in order of their layout in SPSR_EL2. This
layout can be seen in the diagram on ARM DDI 0487E.a page C5-426.

Note that this code is used by both arm and arm64, and is intended to
fuction with the SPSR_EL2 and SPSR_HYP layouts.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200108134324.46500-3-mark.rutland@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11 04:35:16 -08:00
Marc Zyngier
9408013caa KVM: arm/arm64: Properly handle faulting of device mappings
commit 6d674e28f642e3ff676fbae2d8d1b872814d32b6 upstream.

A device mapping is normally always mapped at Stage-2, since there
is very little gain in having it faulted in.

Nonetheless, it is possible to end-up in a situation where the device
mapping has been removed from Stage-2 (userspace munmaped the VFIO
region, and the MMU notifier did its job), but present in a userspace
mapping (userpace has mapped it back at the same address). In such
a situation, the device mapping will be demand-paged as the guest
performs memory accesses.

This requires to be careful when dealing with mapping size, cache
management, and to handle potential execution of a device mapping.

Reported-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Tested-by: Alexandru Elisei <alexandru.elisei@arm.com>
Reviewed-by: James Morse <james.morse@arm.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20191211165651.7889-2-maz@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-31 16:46:24 +01:00
Zenghui Yu
30bd5c4587 KVM: arm/arm64: vgic: Don't rely on the wrong pending table
commit ca185b260951d3b55108c0b95e188682d8a507b7 upstream.

It's possible that two LPIs locate in the same "byte_offset" but target
two different vcpus, where their pending status are indicated by two
different pending tables.  In such a scenario, using last_byte_offset
optimization will lead KVM relying on the wrong pending table entry.
Let us use last_ptr instead, which can be treated as a byte index into
a pending table and also, can be vcpu specific.

Fixes: 280771252c1b ("KVM: arm64: vgic-v3: KVM_DEV_ARM_VGIC_SAVE_PENDING_TABLES")
Cc: stable@vger.kernel.org
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20191029071919.177-4-yuzenghui@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-13 08:43:00 +01:00
Marc Zyngier
8c3252c065 KVM: arm64: pmu: Reset sample period on overflow handling
The PMU emulation code uses the perf event sample period to trigger
the overflow detection. This works fine  for the *first* overflow
handling, but results in a huge number of interrupts on the host,
unrelated to the number of interrupts handled in the guest (a x20
factor is pretty common for the cycle counter). On a slow system
(such as a SW model), this can result in the guest only making
forward progress at a glacial pace.

It turns out that the clue is in the name. The sample period is
exactly that: a period. And once the an overflow has occured,
the following period should be the full width of the associated
counter, instead of whatever the guest had initially programed.

Reset the sample period to the architected value in the overflow
handler, which now results in a number of host interrupts that is
much closer to the number of interrupts in the guest.

Fixes: b02386eb7dac ("arm64: KVM: Add PMU overflow interrupt routing")
Reviewed-by: Andrew Murray <andrew.murray@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-10-20 10:47:07 +01:00
Marc Zyngier
725ce66979 KVM: arm64: pmu: Set the CHAINED attribute before creating the in-kernel event
The current convention for KVM to request a chained event from the
host PMU is to set bit[0] in attr.config1 (PERF_ATTR_CFG1_KVM_PMU_CHAINED).

But as it turns out, this bit gets set *after* we create the kernel
event that backs our virtual counter, meaning that we never get
a 64bit counter.

Moving the setting to an earlier point solves the problem.

Fixes: 80f393a23be6 ("KVM: arm/arm64: Support chained PMU counters")
Reviewed-by: Andrew Murray <andrew.murray@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-10-20 10:47:07 +01:00
Marc Zyngier
f4e23cf947 KVM: arm64: pmu: Fix cycle counter truncation
When a counter is disabled, its value is sampled before the event
is being disabled, and the value written back in the shadow register.

In that process, the value gets truncated to 32bit, which is adequate
for any counter but the cycle counter (defined as a 64bit counter).

This obviously results in a corrupted counter, and things like
"perf record -e cycles" not working at all when run in a guest...
A similar, but less critical bug exists in kvm_pmu_get_counter_value.

Make the truncation conditional on the counter not being the cycle
counter, which results in a minor code reorganisation.

Fixes: 80f393a23be6 ("KVM: arm/arm64: Support chained PMU counters")
Reviewed-by: Andrew Murray <andrew.murray@arm.com>
Reported-by: Julien Thierry <julien.thierry.kdev@gmail.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-10-20 10:47:07 +01:00
Paolo Bonzini
d53a4c8e77 KVM/arm fixes for 5.4, take #1
- Remove the now obsolete hyp_alternate_select construct
 - Fix the TRACE_INCLUDE_PATH macro in the vgic code
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Merge tag 'kvmarm-fixes-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm fixes for 5.4, take #1

- Remove the now obsolete hyp_alternate_select construct
- Fix the TRACE_INCLUDE_PATH macro in the vgic code
2019-10-03 12:08:50 +02:00
Linus Torvalds
fe38bd6862 * s390: ioctl hardening, selftests
* ARM: ITS translation cache; support for 512 vCPUs, various cleanups
 and bugfixes
 
 * PPC: various minor fixes and preparation
 
 * x86: bugfixes all over the place (posted interrupts, SVM, emulation
 corner cases, blocked INIT), some IPI optimizations
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "s390:
   - ioctl hardening
   - selftests

  ARM:
   - ITS translation cache
   - support for 512 vCPUs
   - various cleanups and bugfixes

  PPC:
   - various minor fixes and preparation

  x86:
   - bugfixes all over the place (posted interrupts, SVM, emulation
     corner cases, blocked INIT)
   - some IPI optimizations"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (75 commits)
  KVM: X86: Use IPI shorthands in kvm guest when support
  KVM: x86: Fix INIT signal handling in various CPU states
  KVM: VMX: Introduce exit reason for receiving INIT signal on guest-mode
  KVM: VMX: Stop the preemption timer during vCPU reset
  KVM: LAPIC: Micro optimize IPI latency
  kvm: Nested KVM MMUs need PAE root too
  KVM: x86: set ctxt->have_exception in x86_decode_insn()
  KVM: x86: always stop emulation on page fault
  KVM: nVMX: trace nested VM-Enter failures detected by H/W
  KVM: nVMX: add tracepoint for failed nested VM-Enter
  x86: KVM: svm: Fix a check in nested_svm_vmrun()
  KVM: x86: Return to userspace with internal error on unexpected exit reason
  KVM: x86: Add kvm_emulate_{rd,wr}msr() to consolidate VXM/SVM code
  KVM: x86: Refactor up kvm_{g,s}et_msr() to simplify callers
  doc: kvm: Fix return description of KVM_SET_MSRS
  KVM: X86: Tune PLE Window tracepoint
  KVM: VMX: Change ple_window type to unsigned int
  KVM: X86: Remove tailing newline for tracepoints
  KVM: X86: Trace vcpu_id for vmexit
  KVM: x86: Manually calculate reserved bits when loading PDPTRS
  ...
2019-09-18 09:49:13 -07:00
Zenghui Yu
aac60f1a86 KVM: arm/arm64: vgic: Use the appropriate TRACE_INCLUDE_PATH
Commit 49dfe94fe5ad ("KVM: arm/arm64: Fix TRACE_INCLUDE_PATH") fixes
TRACE_INCLUDE_PATH to the correct relative path to the define_trace.h
and explains why did the old one work.

The same fix should be applied to virt/kvm/arm/vgic/trace.h.

Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-09-11 16:36:19 +01:00
Marc Zyngier
92f35b751c KVM: arm/arm64: vgic: Allow more than 256 vcpus for KVM_IRQ_LINE
While parts of the VGIC support a large number of vcpus (we
bravely allow up to 512), other parts are more limited.

One of these limits is visible in the KVM_IRQ_LINE ioctl, which
only allows 256 vcpus to be signalled when using the CPU or PPI
types. Unfortunately, we've cornered ourselves badly by allocating
all the bits in the irq field.

Since the irq_type subfield (8 bit wide) is currently only taking
the values 0, 1 and 2 (and we have been careful not to allow anything
else), let's reduce this field to only 4 bits, and allocate the
remaining 4 bits to a vcpu2_index, which acts as a multiplier:

  vcpu_id = 256 * vcpu2_index + vcpu_index

With that, and a new capability (KVM_CAP_ARM_IRQ_LINE_LAYOUT_2)
allowing this to be discovered, it becomes possible to inject
PPIs to up to 4096 vcpus. But please just don't.

Whilst we're there, add a clarification about the use of KVM_IRQ_LINE
on arm, which is not completely conditionned by KVM_CAP_IRQCHIP.

Reported-by: Zenghui Yu <yuzenghui@huawei.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-09-09 12:29:09 +01:00
Linus Torvalds
9cf6b756cd arm64 fixes for -rc7
- Fix GICv2 emulation bug (KVM)
 
 - Fix deadlock in virtual GIC interrupt injection code (KVM)
 
 - Fix kprobes blacklist init failure due to broken kallsyms lookup
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Will Deacon:
 "Hot on the heels of our last set of fixes are a few more for -rc7.

  Two of them are fixing issues with our virtual interrupt controller
  implementation in KVM/arm, while the other is a longstanding but
  straightforward kallsyms fix which was been acked by Masami and
  resolves an initialisation failure in kprobes observed on arm64.

   - Fix GICv2 emulation bug (KVM)

   - Fix deadlock in virtual GIC interrupt injection code (KVM)

   - Fix kprobes blacklist init failure due to broken kallsyms lookup"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  KVM: arm/arm64: vgic-v2: Handle SGI bits in GICD_I{S,C}PENDR0 as WI
  KVM: arm/arm64: vgic: Fix potential deadlock when ap_list is long
  kallsyms: Don't let kallsyms_lookup_size_offset() fail on retrieving the first symbol
2019-08-28 10:37:21 -07:00
Marc Zyngier
82e40f558d KVM: arm/arm64: vgic-v2: Handle SGI bits in GICD_I{S,C}PENDR0 as WI
A guest is not allowed to inject a SGI (or clear its pending state)
by writing to GICD_ISPENDR0 (resp. GICD_ICPENDR0), as these bits are
defined as WI (as per ARM IHI 0048B 4.3.7 and 4.3.8).

Make sure we correctly emulate the architecture.

Fixes: 96b298000db4 ("KVM: arm/arm64: vgic-new: Add PENDING registers handlers")
Cc: stable@vger.kernel.org # 4.7+
Reported-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
2019-08-28 11:21:42 +01:00
Heyi Guo
d4a8061a7c KVM: arm/arm64: vgic: Fix potential deadlock when ap_list is long
If the ap_list is longer than 256 entries, merge_final() in list_sort()
will call the comparison callback with the same element twice, causing
a deadlock in vgic_irq_cmp().

Fix it by returning early when irqa == irqb.

Cc: stable@vger.kernel.org # 4.7+
Fixes: 8e4447457965 ("KVM: arm/arm64: vgic-new: Add IRQ sorting")
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Heyi Guo <guoheyi@huawei.com>
[maz: massaged commit log and patch, added Fixes and Cc-stable]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
2019-08-27 16:19:56 +01:00
Eric Auger
3109741a8d KVM: arm/arm64: vgic: Use a single IO device per redistributor
At the moment we use 2 IO devices per GICv3 redistributor: one
one for the RD_base frame and one for the SGI_base frame.

Instead we can use a single IO device per redistributor (the 2
frames are contiguous). This saves slots on the KVM_MMIO_BUS
which is currently limited to NR_IOBUS_DEVS (1000).

This change allows to instantiate up to 512 redistributors and may
speed the guest boot with a large number of VCPUs.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-25 11:02:52 +01:00
Marc Zyngier
926c61568d KVM: arm/arm64: vgic: Remove spurious semicolons
Detected by Coccinelle (and Will Deacon) using
scripts/coccinelle/misc/semicolon.cocci.

Reported-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-25 11:02:13 +01:00
Will Deacon
087eeea9ad KVM/arm fixes for 5.3, take #3
- Don't overskip instructions on MMIO emulation
 - Fix UBSAN splat when initializing PPI priorities
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Merge tag 'kvmarm-fixes-for-5.3-3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm/fixes

Pull KVM/arm fixes from Marc Zyngier as per Paulo's request at:

  https://lkml.kernel.org/r/21ae69a2-2546-29d0-bff6-2ea825e3d968@redhat.com

  "One (hopefully last) set of fixes for KVM/arm for 5.3: an embarassing
   MMIO emulation regression, and a UBSAN splat. Oh well...

   - Don't overskip instructions on MMIO emulation

   - Fix UBSAN splat when initializing PPI priorities"

* tag 'kvmarm-fixes-for-5.3-3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm:
  KVM: arm/arm64: VGIC: Properly initialise private IRQ affinity
  KVM: arm/arm64: Only skip MMIO insn once
2019-08-24 12:46:30 +01:00
Andre Przywara
2e16f3e926 KVM: arm/arm64: VGIC: Properly initialise private IRQ affinity
At the moment we initialise the target *mask* of a virtual IRQ to the
VCPU it belongs to, even though this mask is only defined for GICv2 and
quickly runs out of bits for many GICv3 guests.
This behaviour triggers an UBSAN complaint for more than 32 VCPUs:
------
[ 5659.462377] UBSAN: Undefined behaviour in virt/kvm/arm/vgic/vgic-init.c:223:21
[ 5659.471689] shift exponent 32 is too large for 32-bit type 'unsigned int'
------
Also for GICv3 guests the reporting of TARGET in the "vgic-state" debugfs
dump is wrong, due to this very same problem.

Because there is no requirement to create the VGIC device before the
VCPUs (and QEMU actually does it the other way round), we can't safely
initialise mpidr or targets in kvm_vgic_vcpu_init(). But since we touch
every private IRQ for each VCPU anyway later (in vgic_init()), we can
just move the initialisation of those fields into there, where we
definitely know the VGIC type.

On the way make sure we really have either a VGICv2 or a VGICv3 device,
since the existing code is just checking for "VGICv3 or not", silently
ignoring the uninitialised case.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reported-by: Dave Martin <dave.martin@arm.com>
Tested-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-23 17:23:01 +01:00
Andrew Jones
2113c5f62b KVM: arm/arm64: Only skip MMIO insn once
If after an MMIO exit to userspace a VCPU is immediately run with an
immediate_exit request, such as when a signal is delivered or an MMIO
emulation completion is needed, then the VCPU completes the MMIO
emulation and immediately returns to userspace. As the exit_reason
does not get changed from KVM_EXIT_MMIO in these cases we have to
be careful not to complete the MMIO emulation again, when the VCPU is
eventually run again, because the emulation does an instruction skip
(and doing too many skips would be a waste of guest code :-) We need
to use additional VCPU state to track if the emulation is complete.
As luck would have it, we already have 'mmio_needed', which even
appears to be used in this way by other architectures already.

Fixes: 0d640732dbeb ("arm64: KVM: Skip MMIO insn after emulation")
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-22 13:19:56 +01:00
Alexandru Elisei
0ed5f5d639 KVM: arm/arm64: vgic: Make function comments match function declarations
Since commit 503a62862e8f ("KVM: arm/arm64: vgic: Rely on the GIC driver to
parse the firmware tables"), the vgic_v{2,3}_probe functions stopped using
a DT node. Commit 909777324588 ("KVM: arm/arm64: vgic-new: vgic_init:
implement kvm_vgic_hyp_init") changed the functions again, and now they
require exactly one argument, a struct gic_kvm_info populated by the GIC
driver. Unfortunately the comments regressed and state that a DT node is
used instead. Change the function comments to reflect the current
prototypes.

Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-18 18:44:04 +01:00
Marc Zyngier
41108170d9 KVM: arm/arm64: vgic-irqfd: Implement kvm_arch_set_irq_inatomic
Now that we have a cache of MSI->LPI translations, it is pretty
easy to implement kvm_arch_set_irq_inatomic (this cache can be
parsed without sleeping).

Hopefully, this will improve some LPI-heavy workloads.

Tested-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-18 18:38:54 +01:00
Marc Zyngier
86a7dae884 KVM: arm/arm64: vgic-its: Check the LPI translation cache on MSI injection
When performing an MSI injection, let's first check if the translation
is already in the cache. If so, let's inject it quickly without
going through the whole translation process.

Tested-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-18 18:38:53 +01:00
Marc Zyngier
89489ee9ce KVM: arm/arm64: vgic-its: Cache successful MSI->LPI translation
On a successful translation, preserve the parameters in the LPI
translation cache. Each translation is reusing the last slot
in the list, naturally evicting the least recently used entry.

Tested-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-18 18:38:52 +01:00
Marc Zyngier
cbfda481d8 KVM: arm/arm64: vgic-its: Invalidate MSI-LPI translation cache on vgic teardown
In order to avoid leaking vgic_irq structures on teardown, we need to
drop all references to LPIs before deallocating the cache itself.

This is done by invalidating the cache on vgic teardown.

Tested-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-18 18:38:51 +01:00
Marc Zyngier
363518f37a KVM: arm/arm64: vgic-its: Invalidate MSI-LPI translation cache on ITS disable
If an ITS gets disabled, we need to make sure that further interrupts
won't hit in the cache. For that, we invalidate the translation cache
when the ITS is disabled.

Tested-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-18 18:38:49 +01:00
Marc Zyngier
b4931afcde KVM: arm/arm64: vgic-its: Invalidate MSI-LPI translation cache on disabling LPIs
If a vcpu disables LPIs at its redistributor level, we need to make sure
we won't pend more interrupts. For this, we need to invalidate the LPI
translation cache.

Tested-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-18 18:38:47 +01:00
Marc Zyngier
0c14484866 KVM: arm/arm64: vgic-its: Invalidate MSI-LPI translation cache on specific commands
The LPI translation cache needs to be discarded when an ITS command
may affect the translation of an LPI (DISCARD, MAPC and MAPD with V=0)
or the routing of an LPI to a redistributor with disabled LPIs (MOVI,
MOVALL).

We decide to perform a full invalidation of the cache, irrespective
of the LPI that is affected. Commands are supposed to be rare enough
that it doesn't matter.

Tested-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-18 18:38:45 +01:00
Marc Zyngier
7d825fd6ea KVM: arm/arm64: vgic-its: Add MSI-LPI translation cache invalidation
There's a number of cases where we need to invalidate the caching
of translations, so let's add basic support for that.

Tested-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-18 18:38:42 +01:00
Marc Zyngier
1bb3691d83 KVM: arm/arm64: vgic: Add __vgic_put_lpi_locked primitive
Our LPI translation cache needs to be able to drop the refcount
on an LPI whilst already holding the lpi_list_lock.

Let's add a new primitive for this.

Tested-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-18 18:38:39 +01:00
Marc Zyngier
24cab82c34 KVM: arm/arm64: vgic: Add LPI translation cache definition
Add the basic data structure that expresses an MSI to LPI
translation as well as the allocation/release hooks.

The size of the cache is arbitrarily defined as 16*nr_vcpus.

Tested-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-18 18:38:35 +01:00
Paolo Bonzini
a738b5e75b KVM/arm fixes for 5.3, take #2
- Fix our system register reset so that we stop writing
   non-sensical values to them, and track which registers
   get reset instead.
 - Sync VMCR back from the GIC on WFI so that KVM has an
   exact vue of PMR.
 - Reevaluate state of HW-mapped, level triggered interrupts
   on enable.
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Merge tag 'kvmarm-fixes-for-5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm fixes for 5.3, take #2

- Fix our system register reset so that we stop writing
  non-sensical values to them, and track which registers
  get reset instead.
- Sync VMCR back from the GIC on WFI so that KVM has an
  exact vue of PMR.
- Reevaluate state of HW-mapped, level triggered interrupts
  on enable.
2019-08-09 16:53:50 +02:00
Paolo Bonzini
0e1c438c44 KVM/arm fixes for 5.3
- A bunch of switch/case fall-through annotation, fixing one actual bug
 - Fix PMU reset bug
 - Add missing exception class debug strings
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Merge tag 'kvmarm-fixes-for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm fixes for 5.3

- A bunch of switch/case fall-through annotation, fixing one actual bug
- Fix PMU reset bug
- Add missing exception class debug strings
2019-08-09 16:53:39 +02:00
Alexandru Elisei
16e604a437 KVM: arm/arm64: vgic: Reevaluate level sensitive interrupts on enable
A HW mapped level sensitive interrupt asserted by a device will not be put
into the ap_list if it is disabled at the VGIC level. When it is enabled
again, it will be inserted into the ap_list and written to a list register
on guest entry regardless of the state of the device.

We could argue that this can also happen on real hardware, when the command
to enable the interrupt reached the GIC before the device had the chance to
de-assert the interrupt signal; however, we emulate the distributor and
redistributors in software and we can do better than that.

Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-09 08:07:26 +01:00
Marc Zyngier
5eeaf10eec KVM: arm/arm64: Sync ICH_VMCR_EL2 back when about to block
Since commit commit 328e56647944 ("KVM: arm/arm64: vgic: Defer
touching GICH_VMCR to vcpu_load/put"), we leave ICH_VMCR_EL2 (or
its GICv2 equivalent) loaded as long as we can, only syncing it
back when we're scheduled out.

There is a small snag with that though: kvm_vgic_vcpu_pending_irq(),
which is indirectly called from kvm_vcpu_check_block(), needs to
evaluate the guest's view of ICC_PMR_EL1. At the point were we
call kvm_vcpu_check_block(), the vcpu is still loaded, and whatever
changes to PMR is not visible in memory until we do a vcpu_put().

Things go really south if the guest does the following:

	mov x0, #0	// or any small value masking interrupts
	msr ICC_PMR_EL1, x0

	[vcpu preempted, then rescheduled, VMCR sampled]

	mov x0, #ff	// allow all interrupts
	msr ICC_PMR_EL1, x0
	wfi		// traps to EL2, so samping of VMCR

	[interrupt arrives just after WFI]

Here, the hypervisor's view of PMR is zero, while the guest has enabled
its interrupts. kvm_vgic_vcpu_pending_irq() will then say that no
interrupts are pending (despite an interrupt being received) and we'll
block for no reason. If the guest doesn't have a periodic interrupt
firing once it has blocked, it will stay there forever.

To avoid this unfortuante situation, let's resync VMCR from
kvm_arch_vcpu_blocking(), ensuring that a following kvm_vcpu_check_block()
will observe the latest value of PMR.

This has been found by booting an arm64 Linux guest with the pseudo NMI
feature, and thus using interrupt priorities to mask interrupts instead
of the usual PSTATE masking.

Cc: stable@vger.kernel.org # 4.12
Fixes: 328e56647944 ("KVM: arm/arm64: vgic: Defer touching GICH_VMCR to vcpu_load/put")
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-05 15:36:46 +01:00
Paolo Bonzini
741cbbae07 KVM: remove kvm_arch_has_vcpu_debugfs()
There is no need for this function as all arches have to implement
kvm_arch_create_vcpu_debugfs() no matter what.  A #define symbol
let us actually simplify the code.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-08-05 12:55:48 +02:00
Anders Roxell
1a8248c74c KVM: arm: vgic-v3: Mark expected switch fall-through
When fall-through warnings was enabled by default the following warnings
was starting to show up:

../virt/kvm/arm/hyp/vgic-v3-sr.c: In function ‘__vgic_v3_save_aprs’:
../virt/kvm/arm/hyp/vgic-v3-sr.c:351:24: warning: this statement may fall
 through [-Wimplicit-fallthrough=]
   cpu_if->vgic_ap0r[2] = __vgic_v3_read_ap0rn(2);
   ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
../virt/kvm/arm/hyp/vgic-v3-sr.c:352:2: note: here
  case 6:
  ^~~~
../virt/kvm/arm/hyp/vgic-v3-sr.c:353:24: warning: this statement may fall
 through [-Wimplicit-fallthrough=]
   cpu_if->vgic_ap0r[1] = __vgic_v3_read_ap0rn(1);
   ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
../virt/kvm/arm/hyp/vgic-v3-sr.c:354:2: note: here
  default:
  ^~~~~~~

Rework so that the compiler doesn't warn about fall-through.

Fixes: d93512ef0f0e ("Makefile: Globally enable fall-through warning")
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-07-26 15:37:11 +01:00
Christoph Hellwig
2f5947dfca Documentation: move Documentation/virtual to Documentation/virt
Renaming docs seems to be en vogue at the moment, so fix on of the
grossly misnamed directories.  We usually never use "virtual" as
a shortcut for virtualization in the kernel, but always virt,
as seen in the virt/ top-level directory.  Fix up the documentation
to match that.

Fixes: ed16648eb5b8 ("Move kvm, uml, and lguest subdirectories under a common "virtual" directory, I.E:")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-07-24 10:52:11 +02:00