100 Commits
Author SHA1 Message Date
Marc Zyngier cbc6d44867 KVM: arm64: Add Oliver as a reviewer
Oliver Upton has agreed to help with reviewing the KVM/arm64
patches, and has been doing so for a while now, so adding him
as to the reviewer list.

Note that Oliver is using a different email address for this
purpose, rather than the one his been using for his other
contributions.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Oliver Upton <oupton@google.com>
Link: https://lore.kernel.org/r/20220616085318.1303657-1-maz@kernel.org
2022-06-17 09:49:41 +01:00
Marc Zyngier 668a9fe5c6 genirq: PM: Use runtime PM for chained interrupts
When requesting an interrupt, we correctly call into the runtime
PM framework to guarantee that the underlying interrupt controller
is up and running.

However, we fail to do so for chained interrupt controllers, as
the mux interrupt is not requested along the same path.

Augment __irq_do_set_handler() to call into the runtime PM code
in this case, making sure the PM flow is the same for all interrupts.

Reported-by: Lucas Stach <l.stach@pengutronix.de>
Tested-by: Liu Ying <victor.liu@nxp.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/26973cddee5f527ea17184c0f3fccb70bc8969a0.camel@pengutronix.de
2022-06-09 15:58:13 +01:00
Marc Zyngier bcbfb588cf KVM: arm64: Drop stale comment
The layout of 'struct kvm_vcpu_arch' has evolved significantly since
the initial port of KVM/arm64, so remove the stale comment suggesting
that a prefix of the structure is used exclusively from assembly code.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220609121223.2551-7-will@kernel.org
2022-06-09 13:24:02 +01:00
Marc Zyngier fa7a172144 KVM: arm64: Handle all ID registers trapped for a protected VM
A protected VM accessing ID_AA64ISAR2_EL1 gets punished with an UNDEF,
while it really should only get a zero back if the register is not
handled by the hypervisor emulation (as mandated by the architecture).

Introduce all the missing ID registers (including the unallocated ones),
and have them to return 0.

Reported-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220609121223.2551-3-will@kernel.org
2022-06-09 13:24:02 +01:00
Marc Zyngier efedd01de4 KVM: arm64: Warn if accessing timer pending state outside of vcpu context
A recurrent bug in the KVM/arm64 code base consists in trying to
access the timer pending state outside of the vcpu context, which
makes zero sense (the pending state only exists when the vcpu
is loaded).

In order to avoid more embarassing crashes and catch the offenders
red-handed, add a warning to kvm_arch_timer_get_input_level() and
return the state as non-pending. This avoids taking the system down,
and still helps tracking down silly bugs.

Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220607131427.1164881-4-maz@kernel.org
2022-06-08 10:16:23 +01:00
Marc Zyngier 98432ccdec KVM: arm64: Replace vgic_v3_uaccess_read_pending with vgic_uaccess_read_pending
Now that GICv2 has a proper userspace accessor for the pending state,
switch GICv3 over to it, dropping the local version, moving over the
specific behaviours that CGIv3 requires (such as the distinction
between pending latch and line level which were never enforced
with GICv2).

We also gain extra locking that isn't really necessary for userspace,
but that's a small price to pay for getting rid of superfluous code.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20220607131427.1164881-3-maz@kernel.org
2022-06-08 10:16:15 +01:00
Marc Zyngier 2cdea19a34 KVM: arm64: Don't read a HW interrupt pending state in user context
Since 5bfa685e62 ("KVM: arm64: vgic: Read HW interrupt pending state
from the HW"), we're able to source the pending bit for an interrupt
that is stored either on the physical distributor or on a device.

However, this state is only available when the vcpu is loaded,
and is not intended to be accessed from userspace. Unfortunately,
the GICv2 emulation doesn't provide specific userspace accessors,
and we fallback with the ones that are intended for the guest,
with fatal consequences.

Add a new vgic_uaccess_read_pending() accessor for userspace
to use, build on top of the existing vgic_mmio_read_pending().

Reported-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Fixes: 5bfa685e62 ("KVM: arm64: vgic: Read HW interrupt pending state from the HW")
Link: https://lore.kernel.org/r/20220607131427.1164881-2-maz@kernel.org
Cc: stable@vger.kernel.org
2022-06-07 16:28:19 +01:00
Marc Zyngier 039f49c4ca KVM: arm64: Always start with clearing SME flag on load
On each vcpu load, we set the KVM_ARM64_HOST_SME_ENABLED
flag if SME is enabled for EL0 on the host. This is used to
restore the correct state on vpcu put.

However, it appears that nothing ever clears this flag. Once
set, it will stick until the vcpu is destroyed, which has the
potential to spuriously enable SME for userspace. As it turns
out, this is due to the SME code being more or less copied from
SVE, and inheriting the same shortcomings.

We never saw the issue because nothing uses SME, and the amount
of testing is probably still pretty low.

Fixes: 861262ab86 ("KVM: arm64: Handle SME host state when running guests")
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviwed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220528113829.1043361-3-maz@kernel.org
2022-06-07 14:31:30 +01:00
Marc Zyngier d52d165d67 KVM: arm64: Always start with clearing SVE flag on load
On each vcpu load, we set the KVM_ARM64_HOST_SVE_ENABLED
flag if SVE is enabled for EL0 on the host. This is used to restore
the correct state on vpcu put.

However, it appears that nothing ever clears this flag. Once
set, it will stick until the vcpu is destroyed, which has the
potential to spuriously enable SVE for userspace.

We probably never saw the issue because no VMM uses SVE, but
that's still pretty bad. Unconditionally clearing the flag
on vcpu load addresses the issue.

Fixes: 8383741ab2 ("KVM: arm64: Get rid of host SVE tracking/saving")
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220528113829.1043361-2-maz@kernel.org
2022-06-07 14:19:23 +01:00
Marc Zyngier 492449ae4f Merge branch irq/gic-v3-nmi-fixes-5.19 into irq/irqchip-next
* irq/gic-v3-nmi-fixes-5.19:
  : .
  : GICv3 pseudo-NMI fixes from Mark Rutland:
  :
  : "These patches fix a couple of issues with the way GICv3 pseudo-NMIs are
  : handled:
  :
  : * The first patch adds a barrier we missed from NMI handling due to an
  :   oversight.
  :
  : * The second patch refactors some logic around reads from ICC_IAR1_EL1
  :   and adds commentary to explain what's going on.
  :
  : * The third patch descends into madness, reworking gic_handle_irq() to
  :   consistently manage ICC_PMR_EL1 + DAIF and avoid cases where these can
  :   be left in an inconsistent state while softirqs are processed."
  : .
  irqchip/gic-v3: Fix priority mask handling
  irqchip/gic-v3: Refactor ISB + EOIR at ack time
  irqchip/gic-v3: Ensure pseudo-NMIs have an ISB between ack and handling

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-17 10:37:06 +01:00
Marc Zyngier 61299e1838 Merge branch irq/misc-5.19 into irq/irqchip-next
* irq/misc-5.19:
  : .
  : Misc fixes and minor improvements:
  :
  : - GIC: Improve warning when the firmware tables are inconsistent
  :
  : - csky: Use true/false as boolean litterals
  :
  : - imx-irqsteer: Add runtime PM support
  :
  : - armada-370-xp: Enable CPU affinity for MSIs, avoid messing with
  :   PMU interrupts on some variants
  :
  : - aspeed: Fix handling of irq_of_parse_and_map() errors
  :
  : - sun6i: Fix sparse warnings
  :
  : - xtensa-mx: Fix initial IRQ affinity in non-SMP setup
  :
  : - exiu: Fix acknowledgment of edge-triggered interrupts
  :
  : - sunxi: Generalise configuration for further reuse
  : .
  irqchip: Add Kconfig symbols for sunxi drivers
  irqchip/armada-370-xp: Do not touch Performance Counter Overflow on A375, A38x, A39x
  irqchip/gic: Improved warning about incorrect type
  irqchip/csky: Return true/false (not 1/0) from bool functions
  irqchip/imx-irqsteer: Add runtime PM support
  irqchip/imx-irqsteer: Constify irq_chip struct
  irqchip/armada-370-xp: Enable MSI affinity configuration
  irqchip/aspeed-scu-ic: Fix irq_of_parse_and_map() return value
  irqchip/aspeed-i2c-ic: Fix irq_of_parse_and_map() return value
  irqchip/sun6i-r: Use NULL for chip_data
  irqchip/xtensa-mx: Fix initial IRQ affinity in non-SMP setup
  irqchip/exiu: Fix acknowledgment of edge triggered interrupts

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-17 10:36:56 +01:00
Marc Zyngier 5c0ad551e9 Merge branch kvm-arm64/its-save-restore-fixes-5.19 into kvmarm-master/next
* kvm-arm64/its-save-restore-fixes-5.19:
  : .
  : Tighten the ITS save/restore infrastructure to fail early rather
  : than late. Patches courtesy of Rocardo Koller.
  : .
  KVM: arm64: vgic: Undo work in failed ITS restores
  KVM: arm64: vgic: Do not ignore vgic_its_restore_cte failures
  KVM: arm64: vgic: Add more checks when restoring ITS tables
  KVM: arm64: vgic: Check that new ITEs could be saved in guest memory

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-16 17:48:36 +01:00
Marc Zyngier 822ca7f82b Merge branch kvm-arm64/misc-5.19 into kvmarm-master/next
* kvm-arm64/misc-5.19:
  : .
  : Misc fixes and general improvements for KVMM/arm64:
  :
  : - Better handle out of sequence sysregs in the global tables
  :
  : - Remove a couple of unnecessary loads from constant pool
  :
  : - Drop unnecessary pKVM checks
  :
  : - Add all known M1 implementations to the SEIS workaround
  :
  : - Cleanup kerneldoc warnings
  : .
  KVM: arm64: vgic-v3: List M1 Pro/Max as requiring the SEIS workaround
  KVM: arm64: pkvm: Don't mask already zeroed FEAT_SVE
  KVM: arm64: pkvm: Drop unnecessary FP/SIMD trap handler
  KVM: arm64: nvhe: Eliminate kernel-doc warnings
  KVM: arm64: Avoid unnecessary absolute addressing via literals
  KVM: arm64: Print emulated register table name when it is unsorted
  KVM: arm64: Don't BUG_ON() if emulated register table is unsorted

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-16 17:48:36 +01:00
Marc Zyngier 8794b4f510 Merge branch kvm-arm64/per-vcpu-host-pmu-data into kvmarm-master/next
* kvm-arm64/per-vcpu-host-pmu-data:
  : .
  : Pass the host PMU state in the vcpu to avoid the use of additional
  : shared memory between EL1 and EL2 (this obviously only applies
  : to nVHE and Protected setups).
  :
  : Patches courtesy of Fuad Tabba.
  : .
  KVM: arm64: pmu: Restore compilation when HW_PERF_EVENTS isn't selected
  KVM: arm64: Reenable pmu in Protected Mode
  KVM: arm64: Pass pmu events to hyp via vcpu
  KVM: arm64: Repack struct kvm_pmu to reduce size
  KVM: arm64: Wrapper for getting pmu_events

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-16 17:48:36 +01:00
Marc Zyngier ec2cff6cbd Merge branch kvm-arm64/vgic-invlpir into kvmarm-master/next
* kvm-arm64/vgic-invlpir:
  : .
  : Implement MMIO-based LPI invalidation for vGICv3.
  : .
  KVM: arm64: vgic-v3: Advertise GICR_CTLR.{IR, CES} as a new GICD_IIDR revision
  KVM: arm64: vgic-v3: Implement MMIO-based LPI invalidation
  KVM: arm64: vgic-v3: Expose GICR_CTLR.RWP when disabling LPIs
  irqchip/gic-v3: Exposes bit values for GICR_CTLR.{IR, CES}

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-16 17:48:35 +01:00
Marc Zyngier 3b8e21e3c3 Merge branch kvm-arm64/psci-suspend into kvmarm-master/next
* kvm-arm64/psci-suspend:
  : .
  : Add support for PSCI SYSTEM_SUSPEND and allow userspace to
  : filter the wake-up events.
  :
  : Patches courtesy of Oliver.
  : .
  Documentation: KVM: Fix title level for PSCI_SUSPEND
  selftests: KVM: Test SYSTEM_SUSPEND PSCI call
  selftests: KVM: Refactor psci_test to make it amenable to new tests
  selftests: KVM: Use KVM_SET_MP_STATE to power off vCPU in psci_test
  selftests: KVM: Create helper for making SMCCC calls
  selftests: KVM: Rename psci_cpu_on_test to psci_test
  KVM: arm64: Implement PSCI SYSTEM_SUSPEND
  KVM: arm64: Add support for userspace to suspend a vCPU
  KVM: arm64: Return a value from check_vcpu_requests()
  KVM: arm64: Rename the KVM_REQ_SLEEP handler
  KVM: arm64: Track vCPU power state using MP state values
  KVM: arm64: Dedupe vCPU power off helpers
  KVM: arm64: Don't depend on fallthrough to hide SYSTEM_RESET2

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-16 17:48:20 +01:00
Marc Zyngier 0586e28aaa Merge branch kvm-arm64/hcall-selection into kvmarm-master/next
* kvm-arm64/hcall-selection:
  : .
  : Introduce a new set of virtual sysregs for userspace to
  : select the hypercalls it wants to see exposed to the guest.
  :
  : Patches courtesy of Raghavendra and Oliver.
  : .
  KVM: arm64: Fix hypercall bitmap writeback when vcpus have already run
  KVM: arm64: Hide KVM_REG_ARM_*_BMAP_BIT_COUNT from userspace
  Documentation: Fix index.rst after psci.rst renaming
  selftests: KVM: aarch64: Add the bitmap firmware registers to get-reg-list
  selftests: KVM: aarch64: Introduce hypercall ABI test
  selftests: KVM: Create helper for making SMCCC calls
  selftests: KVM: Rename psci_cpu_on_test to psci_test
  tools: Import ARM SMCCC definitions
  Docs: KVM: Add doc for the bitmap firmware registers
  Docs: KVM: Rename psci.rst to hypercalls.rst
  KVM: arm64: Add vendor hypervisor firmware register
  KVM: arm64: Add standard hypervisor firmware register
  KVM: arm64: Setup a framework for hypercall bitmap firmware registers
  KVM: arm64: Factor out firmware register handling from psci.c

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-16 17:47:03 +01:00
Marc Zyngier 528ada2811 KVM: arm64: Fix hypercall bitmap writeback when vcpus have already run
We generally want to disallow hypercall bitmaps being changed
once vcpus have already run. But we must allow the write if
the written value is unchanged so that userspace can rewrite
the register file on reboot, for example.

Without this, a QEMU-based VM will fail to reboot correctly.

The original code was correct, and it is me that introduced
the regression.

Fixes: 05714cab7d ("KVM: arm64: Setup a framework for hypercall bitmap firmware registers")
Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-16 17:40:48 +01:00
Marc Zyngier 20492a62b9 KVM: arm64: pmu: Restore compilation when HW_PERF_EVENTS isn't selected
Moving kvm_pmu_events into the vcpu (and refering to it) broke the
somewhat unusual case where the kernel has no support for a PMU
at all.

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

Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/202205161814.KQHpOzsJ-lkp@intel.com
2022-05-16 13:42:41 +01:00
Marc Zyngier 5163373af1 KVM: arm64: vgic-v3: Consistently populate ID_AA64PFR0_EL1.GIC
When adding support for the slightly wonky Apple M1, we had to
populate ID_AA64PFR0_EL1.GIC==1 to present something to the guest,
as the HW itself doesn't advertise the feature.

However, we gated this on the in-kernel irqchip being created.
This causes some trouble for QEMU, which snapshots the state of
the registers before creating a virtual GIC, and then tries to
restore these registers once the GIC has been created.  Obviously,
between the two stages, ID_AA64PFR0_EL1.GIC has changed value,
and the write fails.

The fix is to actually emulate the HW, and always populate the
field if the HW is capable of it.

Fixes: 562e530fd7 ("KVM: arm64: Force ID_AA64PFR0_EL1.GIC=1 when exposing a virtual GICv3")
Cc: stable@vger.kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Oliver Upton <oupton@google.com>
Link: https://lore.kernel.org/r/20220503211424.3375263-1-maz@kernel.org
2022-05-15 12:12:14 +01:00
Marc Zyngier 2cde51f1e1 KVM: arm64: Hide KVM_REG_ARM_*_BMAP_BIT_COUNT from userspace
These constants will change over time, and userspace has no
business knowing about them. Hide them behind __KERNEL__.

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-15 11:36:24 +01:00
Marc Zyngier cae889302e KVM: arm64: vgic-v3: List M1 Pro/Max as requiring the SEIS workaround
Unsusprisingly, Apple M1 Pro/Max have the exact same defect as the
original M1 and generate random SErrors in the host when a guest
tickles the GICv3 CPU interface the wrong way.

Add the part numbers for both the CPU types found in these two
new implementations, and add them to the hall of shame. This also
applies to the Ultra version, as it is composed of 2 Max SoCs.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220514102524.3188730-1-maz@kernel.org
2022-05-15 11:18:50 +01:00
Marc Zyngier a6ad8551b8 Merge branch irq/gic-v3-5.19 into irq/irqchip-next
* irq/gic-v3-5.19:
  : .
  : Misc improvements for GICv3:
  :
  : - Minimise the number of cases where we need to poll RWP
  :
  : - Allow the use of MMIO-based invalidation for LPIs
  :
  : - Track GICD/GICR mappings in /proc/iomem
  :
  : - Tighten the GICv3 DT binding to avoid endless discussions
  :   on the list...
  : .
  irqchip/gic-v3: Claim iomem resources
  dt-bindings: interrupt-controller: arm,gic-v3: Make the v2 compat requirements explicit
  irqchip/gic-v3: Relax polling of GIC{R,D}_CTLR.RWP
  irqchip/gic-v3: Detect LPI invalidation MMIO registers
  irqchip/gic-v3: Exposes bit values for GICR_CTLR.{IR, CES}

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-04 16:09:47 +01:00
Marc Zyngier 4053b6b43f dt-bindings: interrupt-controller: arm,gic-v3: Make the v2 compat requirements explicit
A common mistake when writing a device tree for a platform that is using
GICv3 with ancient CPUs is to overlook the MMIO frames that implement
the GICv2 compatibility feature, because this feature is implemented by
the CPUs and not by the GIC itself.

The compatibility feature itself is optional (all the modern
implementations have dropped it), but is present in all the ARM Ltd
implementations of the ARMv8.0 architecture (A3x, A53, A57, A72, A73),
and many others from various implementers.

Make it explicit that GICC, GICH and GICV are required for these CPUs.
Also take this opportunity to update my email address, as people keep
sending them to the wrong place...

Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Krzysztof Kozlowski <krzk+dt@kernel.org>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220409101617.268796-1-maz@kernel.org
2022-05-04 15:43:12 +01:00
Marc Zyngier 63f13483f0 irqchip/gic-v3: Relax polling of GIC{R,D}_CTLR.RWP
Recent work on the KVM GIC emulation has revealed that the GICv3
driver is a bit RWP-happy, as it polls this bit for each and
every write MMIO access involving a single interrupt.

As it turns out, polling RWP is only required when:
- Disabling an SGI, PPI or SPI
- Disabling LPIs at the redistributor level
- Disabling groups
- Enabling ARE
- Dealing with DPG*

Simplify the driver by removing all the other instances of RWP
polling, and add the one that was missing when enabling the distributor
(as that's where we set ARE).

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220405183857.205960-4-maz@kernel.org
2022-05-04 15:38:55 +01:00
Marc Zyngier a837ed362e irqchip/gic-v3: Detect LPI invalidation MMIO registers
Since GICv4.1, an implementation can offer the same MMIO-based
implementation as DirectLPI, only with an ITS. Given that this
can be hugely beneficial for workloads that are very LPI masking
heavy (although these workloads are admitedly a bit odd).

Interestingly, this is independent of RVPEI, which only *implies*
the functionnality.

So let's detect whether the implementation has GICR_CTLR.IR set,
and propagate this as DirectLPI to the ITS driver.

While we're at it, repaint the GICv3 banner so that we advertise
the various capabilities at boot time to be slightly less invasive.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220405183857.205960-3-maz@kernel.org
2022-05-04 15:38:55 +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
Marc Zyngier 34453c2e9f irqchip/gic-v3: Exposes bit values for GICR_CTLR.{IR, CES}
As we're about to expose GICR_CTLR.{IR,CES} to guests, populate
the include file with the architectural values.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Oliver Upton <oupton@google.com>
Link: https://lore.kernel.org/r/20220405182327.205520-2-maz@kernel.org
2022-05-04 14:09:52 +01:00
Marc Zyngier c36820b04c Documentation: Fix index.rst after psci.rst renaming
Fix the TOC in index.rst after psci.rst has been renamed to
hypercalls.rst.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lore.kernel.org/r/20220504205627.18f46380@canb.auug.org.au
2022-05-04 13:13:55 +01:00
Marc Zyngier d25f30fe41 Merge branch kvm-arm64/aarch32-idreg-trap into kvmarm-master/next
* kvm-arm64/aarch32-idreg-trap:
  : .
  : Add trapping/sanitising infrastructure for AArch32 systen registers,
  : allowing more control over what we actually expose (such as the PMU).
  :
  : Patches courtesy of Oliver and Alexandru.
  : .
  KVM: arm64: Fix new instances of 32bit ESRs
  KVM: arm64: Hide AArch32 PMU registers when not available
  KVM: arm64: Start trapping ID registers for 32 bit guests
  KVM: arm64: Plumb cp10 ID traps through the AArch64 sysreg handler
  KVM: arm64: Wire up CP15 feature registers to their AArch64 equivalents
  KVM: arm64: Don't write to Rt unless sys_reg emulation succeeds
  KVM: arm64: Return a bool from emulate_cp()

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-04 09:42:45 +01:00
Marc Zyngier 904cabf471 Merge branch kvm-arm64/hyp-stack-guard into kvmarm-master/next
* kvm-arm64/hyp-stack-guard:
  : .
  : Harden the EL2 stack by providing stack guards, courtesy of
  : Kalesh Singh.
  : .
  KVM: arm64: Symbolize the nVHE HYP addresses
  KVM: arm64: Detect and handle hypervisor stack overflows
  KVM: arm64: Add guard pages for pKVM (protected nVHE) hypervisor stack
  KVM: arm64: Add guard pages for KVM nVHE hypervisor stack
  KVM: arm64: Introduce pkvm_alloc_private_va_range()
  KVM: arm64: Introduce hyp_alloc_private_va_range()

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-04 09:42:37 +01:00
Marc Zyngier b2c4caf331 Merge branch kvm-arm64/wfxt into kvmarm-master/next
* kvm-arm64/wfxt:
  : .
  : Add support for the WFET/WFIT instructions that provide the same
  : service as WFE/WFI, only with a timeout.
  : .
  KVM: arm64: Expose the WFXT feature to guests
  KVM: arm64: Offer early resume for non-blocking WFxT instructions
  KVM: arm64: Handle blocking WFIT instruction
  KVM: arm64: Introduce kvm_counter_compute_delta() helper
  KVM: arm64: Simplify kvm_cpu_has_pending_timer()
  arm64: Use WFxT for __delay() when possible
  arm64: Add wfet()/wfit() helpers
  arm64: Add HWCAP advertising FEAT_WFXT
  arm64: Add RV and RN fields for ESR_ELx_WFx_ISS
  arm64: Expand ESR_ELx_WFx_ISS_TI to match its ARMv8.7 definition

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-04 09:42:16 +01:00
Marc Zyngier 4b88524c47 Merge remote-tracking branch 'arm64/for-next/sme' into kvmarm-master/next
Merge arm64's SME branch to resolve conflicts with the WFxT branch.

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-04 09:38:32 +01:00
Marc Zyngier ee87a9bd65 KVM: arm64: Fix new instances of 32bit ESRs
Fix the new instances of ESR being described as a u32, now that
we consistently are using a u64 for this register.

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-05-04 08:01:05 +01:00
Marc Zyngier 85ea6b1ec9 KVM: arm64: Inject exception on out-of-IPA-range translation fault
When taking a translation fault for an IPA that is outside of
the range defined by the hypervisor (between the HW PARange and
the IPA range), we stupidly treat it as an IO and forward the access
to userspace. Of course, userspace can't do much with it, and things
end badly.

Arguably, the guest is braindead, but we should at least catch the
case and inject an exception.

Check the faulting IPA against:
- the sanitised PARange: inject an address size fault
- the IPA size: inject an abort

Reported-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-04-27 23:02:23 +01:00
Marc Zyngier 06e0b80258 KVM: arm64: Expose the WFXT feature to guests
Plumb in the capability, and expose WFxT to guests when available.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220419182755.601427-8-maz@kernel.org
2022-04-20 13:24:45 +01:00
Marc Zyngier a3fb596514 KVM: arm64: Offer early resume for non-blocking WFxT instructions
For WFxT instructions used with very small delays, it is not
unlikely that the deadline is already expired by the time we
reach the WFx handling code.

Check for this condition as soon as possible, and return to the
guest immediately if we can.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220419182755.601427-7-maz@kernel.org
2022-04-20 13:24:45 +01:00
Marc Zyngier 89f5074c50 KVM: arm64: Handle blocking WFIT instruction
When trapping a blocking WFIT instruction, take it into account when
computing the deadline of the background timer.

The state is tracked with a new vcpu flag, and is gated by a new
CPU capability, which isn't currently enabled.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220419182755.601427-6-maz@kernel.org
2022-04-20 13:24:45 +01:00
Marc Zyngier daf85a5f6b KVM: arm64: Introduce kvm_counter_compute_delta() helper
Refactor kvm_timer_compute_delta() and extract a helper that
compute the delta (in ns) between a given timer and an arbitrary
value.

No functional change expected.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220419182755.601427-5-maz@kernel.org
2022-04-20 13:24:44 +01:00
Marc Zyngier b57de4ffd7 KVM: arm64: Simplify kvm_cpu_has_pending_timer()
kvm_cpu_has_pending_timer() ends up checking all the possible
timers for a wake-up cause. However, we already check for
pending interrupts whenever we try to wake-up a vcpu, including
the timer interrupts.

Obviously, doing the same work twice is once too many. Reduce
this helper to almost nothing, but keep it around, as we are
going to make use of it soon.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220419182755.601427-4-maz@kernel.org
2022-04-20 13:24:44 +01:00
Marc Zyngier 7d26b0516a arm64: Use WFxT for __delay() when possible
Marginally optimise __delay() by using a WFIT/WFET sequence.
It probably is a win if no interrupt fires during the delay.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220419182755.601427-11-maz@kernel.org
2022-04-20 13:24:44 +01:00
Marc Zyngier 9eae588529 arm64: Add wfet()/wfit() helpers
Just like we have helpers for WFI and WFE, add the WFxT versions.
Note that the encoding is that reported by objdump, as no currrent
toolchain knows about these instructions yet.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220419182755.601427-10-maz@kernel.org
2022-04-20 13:24:44 +01:00
Marc Zyngier 69bb02ebc3 arm64: Add HWCAP advertising FEAT_WFXT
In order to allow userspace to enjoy WFET, add a new HWCAP that
advertises it when available.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220419182755.601427-9-maz@kernel.org
2022-04-20 13:24:44 +01:00
Marc Zyngier bdcc2f2803 arm64: Add RV and RN fields for ESR_ELx_WFx_ISS
The ISS field exposed by ESR_ELx contain two additional subfields
with FEAT_WFxT:

- RN, the register number containing the timeout
- RV, indicating if the register number is valid

Describe these two fields according to the arch spec.

No functional change.

Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220419182755.601427-3-maz@kernel.org
2022-04-20 13:00:35 +01:00
Marc Zyngier 6a437208cb arm64: Expand ESR_ELx_WFx_ISS_TI to match its ARMv8.7 definition
Starting with FEAT_WFXT in ARMv8.7, the TI field in the ISS
that is reported on a WFx trap is expanded by one bit to
allow the description of WFET and WFIT.

Special care is taken to exclude the WFxT bit from the mask
used to match WFI so that it also matches WFIT when trapped from
EL0.

Reviewed-by: Joey Gouly <joey.gouly@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220419182755.601427-2-maz@kernel.org
2022-04-20 13:00:34 +01:00
Marc Zyngier 4bde53ab33 Merge branch irq/gpio-immutable into irq/irqchip-next
* irq/gpio-immutable:
  : .
  : First try at preventing the GPIO subsystem from abusing irq_chip
  : data structures. The general idea is to have an irq_chip flag
  : to tell the GPIO subsystem that these structures are immutable,
  : and to convert drivers one by one.
  : .
  Documentation: Update the recommended pattern for GPIO irqchips
  gpio: Update TODO to mention immutable irq_chip structures
  pinctrl: amd: Make the irqchip immutable
  pinctrl: msmgpio: Make the irqchip immutable
  pinctrl: apple-gpio: Make the irqchip immutable
  gpio: pl061: Make the irqchip immutable
  gpio: tegra186: Make the irqchip immutable
  gpio: Add helpers to ease the transition towards immutable irq_chip
  gpio: Expose the gpiochip_irq_re[ql]res helpers
  gpio: Don't fiddle with irqchips marked as immutable

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-04-19 15:23:14 +01:00
Marc Zyngier 5644b66a9c Documentation: Update the recommended pattern for GPIO irqchips
Update the documentation to get rid of the per-gpio_irq_chip
irq_chip structure, and give examples of the new pattern.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220419141846.598305-11-maz@kernel.org
2022-04-19 15:22:27 +01:00
Marc Zyngier afefc32662 gpio: Update TODO to mention immutable irq_chip structures
5 drivers are converted, a few hundred to go. Definitely worth of
a TODO entry, in the hope that someone will notice it and do
a bulk update.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220419141846.598305-10-maz@kernel.org
2022-04-19 15:22:26 +01:00
Marc Zyngier 6173e56f76 pinctrl: amd: Make the irqchip immutable
Prevent gpiolib from messing with the irqchip by advertising
the irq_chip structure as immutable, making it const, and adding
the various calls that gpiolib relies upon.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220419141846.598305-9-maz@kernel.org
2022-04-19 15:22:26 +01:00
Marc Zyngier 14dbe186b9 pinctrl: msmgpio: Make the irqchip immutable
Prevent gpiolib from messing with the irqchip by advertising
the irq_chip structure as immutable, making it const, and adding
the various calls that gpiolib relies upon.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220419141846.598305-8-maz@kernel.org
2022-04-19 15:22:26 +01:00
Marc Zyngier 374b87a0fc pinctrl: apple-gpio: Make the irqchip immutable
Prevent gpiolib from messing with the irqchip by advertising
the irq_chip structure as immutable, making it const, and adding
the various calls that gpiolib relies upon.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220419141846.598305-7-maz@kernel.org
2022-04-19 15:22:26 +01:00
Marc Zyngier 15d8c14ac8 gpio: pl061: Make the irqchip immutable
Prevent gpiolib from messing with the irqchip by advertising
the irq_chip structure as immutable, making it const, and adding
the various calls that gpiolib relies upon.

Reviewed-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220419141846.598305-6-maz@kernel.org
2022-04-19 15:22:26 +01:00
Marc Zyngier bba00555ed gpio: tegra186: Make the irqchip immutable
Prevent gpiolib from messing with the irqchip by advertising
the irq_chip structure as immutable, making it const, and adding
the various calls that gpiolib relies upon.

Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220419141846.598305-5-maz@kernel.org
2022-04-19 15:22:26 +01:00
Marc Zyngier 36b78aae4b gpio: Add helpers to ease the transition towards immutable irq_chip
Add a couple of new helpers to make it slightly simpler to convert
drivers to immutable irq_chip structures:

- GPIOCHIP_IRQ_RESOURCE_HELPERS populates the irq_chip structure
  with the resource management callbacks

- gpio_irq_chip_set_chip() populates the gpio_irq_chip.chip
  structure, avoiding the proliferation of ugly casts

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220419141846.598305-4-maz@kernel.org
2022-04-19 15:22:25 +01:00
Marc Zyngier 704f08753b gpio: Expose the gpiochip_irq_re[ql]res helpers
The GPIO subsystem has a couple of internal helpers to manage
resources on behalf of the irqchip. Expose them so that GPIO
drivers can use them directly.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220419141846.598305-3-maz@kernel.org
2022-04-19 15:22:25 +01:00
Marc Zyngier 6c846d026d gpio: Don't fiddle with irqchips marked as immutable
In order to move away from gpiolib messing with the internals of
unsuspecting irqchips, add a flag by which irqchips advertise
that they are not to be messed with, and do solemnly swear that
they correctly call into the gpiolib helpers when required.

Also nudge the users into converting their drivers to the
new model.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220419141846.598305-2-maz@kernel.org
2022-04-19 15:22:25 +01:00
Marc Zyngier c48c8b829d genirq: Take the proposed affinity at face value if force==true
Although setting the affinity of an interrupt to a set of CPUs that doesn't
have any online CPU is generally frowned apon, there are a few limited
cases where such affinity is set from a CPUHP notifier, setting the
affinity to a CPU that isn't online yet.

The saving grace is that this is always done using the 'force' attribute,
which gives a hint that the affinity setting can be outside of the online
CPU mask and the callsite set this flag with the knowledge that the
underlying interrupt controller knows to handle it.

This restores the expected behaviour on Marek's system.

Fixes: 33de0aa4ba ("genirq: Always limit the affinity to online CPUs")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/4b7fc13c-887b-a664-26e8-45aed13f048a@samsung.com
Link: https://lore.kernel.org/r/20220414140011.541725-1-maz@kernel.org
2022-04-14 16:11:25 +02:00
Marc Zyngier 3f893a5962 irqchip/gic-v3: Always trust the managed affinity provided by the core code
Now that the core code has been fixed to always give us an affinity
that only includes online CPUs, directly use this affinity when
computing a target CPU.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20220405185040.206297-4-maz@kernel.org
2022-04-10 21:06:30 +02:00
Marc Zyngier 33de0aa4ba genirq: Always limit the affinity to online CPUs
When booting with maxcpus=<small number> (or even loading a driver
while most CPUs are offline), it is pretty easy to observe managed
affinities containing a mix of online and offline CPUs being passed
to the irqchip driver.

This means that the irqchip cannot trust the affinity passed down
from the core code, which is a bit annoying and requires (at least
in theory) all drivers to implement some sort of affinity narrowing.

In order to address this, always limit the cpumask to the set of
online CPUs.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20220405185040.206297-3-maz@kernel.org
2022-04-10 21:06:30 +02:00
Marc Zyngier d802057c7c genirq/msi: Shutdown managed interrupts with unsatifiable affinities
When booting with maxcpus=<small number>, interrupt controllers
such as the GICv3 ITS may not be able to satisfy the affinity of
some managed interrupts, as some of the HW resources are simply
not available.

The same thing happens when loading a driver using managed interrupts
while CPUs are offline.

In order to deal with this, do not try to activate such interrupt
if there is no online CPU capable of handling it. Instead, place
it in shutdown state. Once a capable CPU shows up, it will be
activated.

Reported-by: John Garry <john.garry@huawei.com>
Reported-by: David Decotigny <ddecotig@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/20220405185040.206297-2-maz@kernel.org
2022-04-10 21:06:30 +02:00
Marc Zyngier 0df6664531 irqchip/gic-v3: Fix GICR_CTLR.RWP polling
It turns out that our polling of RWP is totally wrong when checking
for it in the redistributors, as we test the *distributor* bit index,
whereas it is a different bit number in the RDs... Oopsie boo.

This is embarassing. Not only because it is wrong, but also because
it took *8 years* to notice the blunder...

Just fix the damn thing.

Fixes: 021f653791 ("irqchip: gic-v3: Initial support for GICv3")
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Link: https://lore.kernel.org/r/20220315165034.794482-2-maz@kernel.org
2022-04-05 16:33:13 +01:00
Marc Zyngier af27e41612 irqchip/gic-v4: Wait for GICR_VPENDBASER.Dirty to clear before descheduling
The way KVM drives GICv4.{0,1} is as follows:
- vcpu_load() makes the VPE resident, instructing the RD to start
  scanning for interrupts
- just before entering the guest, we check that the RD has finished
  scanning and that we can start running the vcpu
- on preemption, we deschedule the VPE by making it invalid on
  the RD

However, we are preemptible between the first two steps. If it so
happens *and* that the RD was still scanning, we nonetheless write
to the GICR_VPENDBASER register while Dirty is set, and bad things
happen (we're in UNPRED land).

This affects both the 4.0 and 4.1 implementations.

Make sure Dirty is cleared before performing the deschedule,
meaning that its_clear_vpend_valid() becomes a sort of full VPE
residency barrier.

Reported-by: Jingyi Wang <wangjingyi11@huawei.com>
Tested-by: Nianyao Tang <tangnianyao@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Fixes: 57e3cebd02 ("KVM: arm64: Delay the polling of the GICR_VPENDBASER.Dirty bit")
Link: https://lore.kernel.org/r/4aae10ba-b39a-5f84-754b-69c2eb0a2c03@huawei.com
2022-04-05 16:33:13 +01:00
Marc Zyngier 825da4e9ce PCI: xgene: Revert "PCI: xgene: Fix IB window setup"
Commit c7a75d0782 ("PCI: xgene: Fix IB window setup") tried to
fix the damages that 6dce5aa59e ("PCI: xgene: Use inbound resources
for setup") caused, but actually didn't improve anything for some
plarforms (at least Mustang and m400 are still broken).

Given that 6dce5aa59e has been reverted, revert this patch as well,
restoring the PCIe support on XGene to its pre-5.5, working state.

Link: https://lore.kernel.org/r/YjN8pT5e6/8cRohQ@xps13.dannf
Link: https://lore.kernel.org/r/20220321104843.949645-3-maz@kernel.org
Fixes: c7a75d0782 ("PCI: xgene: Fix IB window setup")
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: stable@vger.kernel.org
Cc: Rob Herring <robh@kernel.org>
Cc: Toan Le <toan@os.amperecomputing.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Krzysztof Wilczyński <kw@linux.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Stéphane Graber <stgraber@ubuntu.com>
Cc: dann frazier <dann.frazier@canonical.com>
2022-03-21 10:54:18 +00:00
Marc Zyngier 1874b6d7ab PCI: xgene: Revert "PCI: xgene: Use inbound resources for setup"
Commit 6dce5aa59e ("PCI: xgene: Use inbound resources for setup")
killed PCIe on my XGene-1 box (a Mustang board). The machine itself
is still alive, but half of its storage (over NVMe) is gone, and the
NVMe driver just times out.

Note that this machine boots with a device tree provided by the
UEFI firmware (2016 vintage), which could well be non conformant
with the spec, hence the breakage.

With the patch reverted, the box boots 5.17-rc8 with flying colors.

Link: https://lore.kernel.org/all/Yf2wTLjmcRj+AbDv@xps13.dannf
Link: https://lore.kernel.org/r/20220321104843.949645-2-maz@kernel.org
Fixes: 6dce5aa59e ("PCI: xgene: Use inbound resources for setup")
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: stable@vger.kernel.org
Cc: Rob Herring <robh@kernel.org>
Cc: Toan Le <toan@os.amperecomputing.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Krzysztof Wilczyński <kw@linux.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Stéphane Graber <stgraber@ubuntu.com>
Cc: dann frazier <dann.frazier@canonical.com>
2022-03-21 10:54:18 +00:00
Marc Zyngier 06394531b4 KVM: arm64: Generalise VM features into a set of flags
We currently deal with a set of booleans for VM features,
while they could be better represented as set of flags
contained in an unsigned long, similarily to what we are
doing on the CPU side.

Signed-off-by: Marc Zyngier <maz@kernel.org>
[Oliver: Flag-ify the 'ran_once' boolean]
Signed-off-by: Oliver Upton <oupton@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220311174001.605719-2-oupton@google.com
2022-03-18 14:02:33 +00:00
Marc Zyngier de26a74243 Merge branch irq/qcom-mpm into irq/irqchip-next
* irq/qcom-mpm:
  : .
  : Add support for Qualcomm's MPM wakeup controller, courtesy
  : of Shawn Guo.
  : .
  irqchip: Add Qualcomm MPM controller driver
  dt-bindings: interrupt-controller: Add Qualcomm MPM support

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-03-11 19:22:24 +00:00
Marc Zyngier 89ea5be11a Merge branch irq/aic-v2 into irq/irqchip-next
* irq/aic-v2:
  : .
  : Add support for the interrupt controller found is the latest
  : incarnation of Apple M1 systems, courtesy of Hector Martin.
  : .
  irqchip/apple-aic: Add support for AICv2
  irqchip/apple-aic: Support multiple dies
  irqchip/apple-aic: Dynamically compute register offsets
  irqchip/apple-aic: Switch to irq_domain_create_tree and sparse hwirqs
  irqchip/apple-aic: Add Fast IPI support
  dt-bindings: interrupt-controller: apple,aic2: New binding for AICv2
  PCI: apple: Change MSI handling to handle 4-cell AIC fwspec form

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-03-11 09:10:12 +00:00
Marc Zyngier c425060a40 Merge branch irq/aic-pmu into irq/irqchip-next
* irq/aic-pmu:
  : .
  : Prefix branch for the M1 PMU support, adding the required
  : irqchip changes. Shared with the arm64 tree.
  : .
  irqchip/apple-aic: Fix cpumask allocation for FIQs
  irqchip/apple-aic: Move PMU-specific registers to their own include file
  arm64: dts: apple: Add t8303 PMU nodes
  arm64: dts: apple: Add t8103 PMU interrupt affinities
  irqchip/apple-aic: Wire PMU interrupts
  irqchip/apple-aic: Parse FIQ affinities from device-tree
  dt-bindings: apple,aic: Add affinity description for per-cpu pseudo-interrupts
  dt-bindings: apple,aic: Add CPU PMU per-cpu pseudo-interrupts
  dt-bindings: arm-pmu: Document Apple PMU compatible strings

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-03-10 08:59:03 +00:00
Marc Zyngier dc29812dbc irqchip/apple-aic: Fix cpumask allocation for FIQs
An emparassing typo: allocating a pointer instead of the object
pointed to. No harm done, as the pointer is large enough for
what we are using the object for, but still...

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220310050238.4478-1-guozhengkui@vivo.com
2022-03-10 08:58:34 +00:00
Marc Zyngier 9872e6bc08 Merge branch kvm-arm64/psci-1.1 into kvmarm-master/next
* kvm-arm64/psci-1.1:
  : .
  : Limited PSCI-1.1 support from Will Deacon:
  :
  : This small series exposes the PSCI SYSTEM_RESET2 call to guests, which
  : allows the propagation of a "reset_type" and a "cookie" back to the VMM.
  : Although Linux guests only ever pass 0 for the type ("SYSTEM_WARM_RESET"),
  : the vendor-defined range can be used by a bootloader to provide additional
  : information about the reset, such as an error code.
  : .
  KVM: arm64: Really propagate PSCI SYSTEM_RESET2 arguments to userspace

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-03-09 18:19:10 +00:00
Marc Zyngier f90205b953 arm64: Add cavium_erratum_23154_cpus missing sentinel
Qian Cai reported that playing with CPU hotplug resulted in a
out-of-bound access due to cavium_erratum_23154_cpus missing
a sentinel indicating the end of the array.

Add it in order to restore peace and harmony in the world
of broken HW.

Reported-by: Qian Cai <quic_qiancai@quicinc.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Fixes: 24a147bcef ("irqchip/gic-v3: Workaround Marvell erratum 38545 when reading IAR")
Link: https://lore.kernel.org/r/YijmkXp1VG7e8lDx@qian
Cc: Linu Cherian <lcherian@marvell.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20220309180600.3990874-1-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2022-03-09 18:13:57 +00:00
Marc Zyngier 92af5d4790 Merge branch irq/meson-gpio into irq/irqchip-next
* irq/meson-gpio:
  : .
  : Expand meson-gpio support to deal with the new Meson-S4 SoC
  : .
  irqchip/meson-gpio: Add support for meson s4 SoCs
  irqchip/meson-gpio: add select trigger type callback
  irqchip/meson-gpio: support more than 8 channels gpio irq
  dt-bindings: interrupt-controller: New binding for Meson-S4 SoCs

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-03-09 11:21:01 +00:00
Marc Zyngier 7297a8bcc0 Merge branch kvm-arm64/misc-5.18 into kvmarm-master/next
* kvm-arm64/misc-5.18:
  : .
  : Misc fixes for KVM/arm64 5.18:
  :
  : - Drop unused kvm parameter to kvm_psci_version()
  :
  : - Implement CONFIG_DEBUG_LIST at EL2
  :
  : - Make CONFIG_ARM64_ERRATUM_2077057 default y
  :
  : - Only do the interrupt dance if we have exited because of an interrupt
  :
  : - Remove traces of 32bit ARM host support from the documentation
  : .
  Documentation: KVM: Update documentation to indicate KVM is arm64-only
  KVM: arm64: Only open the interrupt window on exit due to an interrupt
  KVM: arm64: Enable Cortex-A510 erratum 2077057 by default

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-03-09 11:16:48 +00:00
Marc Zyngier a639027a1b drivers/perf: Add Apple icestorm/firestorm CPU PMU driver
Add a new, weird and wonderful driver for the equally weird Apple
PMU HW. Although the PMU itself is functional, we don't know much
about the events yet, so this can be considered as yet another
random number generator...

Nonetheless, it can reliably count at least cycles and instructions
in the usually wonky big-little way. For anything else, it of course
supports raw event numbers.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
2022-03-08 13:32:48 +00:00
Marc Zyngier 1280f12f56 drivers/perf: arm_pmu: Handle 47 bit counters
The current ARM PMU framework can only deal with 32 or 64bit counters.
Teach it about a 47bit flavour.

Yes, this is odd.

Reviewed-by: Hector Martin <marcan@marcan.st>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
2022-03-08 13:32:48 +00:00
Marc Zyngier 8c4b810a87 clocksource/drivers/arm_arch_timer: Use event stream scaling when available
With FEAT_ECV and the 1GHz counter, it is pretty likely that the
event stream divider doesn't fit in the field that holds the
divider value (we only have 4 bits to describe counter bits [15:0]

Thankfully, FEAT_ECV also provides a scaling mechanism to switch
the field to cover counter bits [23:8] instead.

Enable this on arm64 when ECV is available (32bit doesn't have
any detection infrastructure and is unlikely to be run on an
ARMv8.6 system anyway).

Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20220203170502.2694422-1-maz@kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2022-03-07 18:27:22 +01:00
Marc Zyngier f7659f8bcd KVM: arm64: Only open the interrupt window on exit due to an interrupt
Now that we properly account for interrupts taken whilst the guest
was running, it becomes obvious that there is no need to open
this accounting window if we didn't exit because of an interrupt.

This saves a number of system register accesses and other barriers
if we exited for any other reason (such as a trap, for example).

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20220304135914.1464721-1-maz@kernel.org
2022-03-04 15:07:04 +00:00
Marc Zyngier 8e6958c80e Merge branch irq/misc-5.18 into irq/irqchip-next
* irq/misc-5.18:
  : .
  : Misc irq chip changes for 5.18
  :
  : - GICv3: Relax ordering of previous stores to only include the ISH domain
  :
  : - nvic: Unmap MMIo region on probe failure
  :
  : - xilinx: Switch to GENERIC_IRQ_MULTI_HANDLER when used on microblaze
  : .
  irqchip/xilinx: Switch to GENERIC_IRQ_MULTI_HANDLER
  irqchip/nvic: Release nvic_base upon failure
  irqchip/gic-v3: Use dsb(ishst) to order writes with ICC_SGI1R_EL1 accesses

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-03-04 14:37:32 +00:00
Marc Zyngier 92877b9e74 Merge branch irq/plic-cleanups into irq/irqchip-next
* irq/plic-cleanups:
  : .
  : SiFive PLIC cleanups from Niklas Cassel:
  :
  : - Clarify some of the namings in the driver
  :
  : - Make sure S-mode interrupts are disabled when running in M-mode
  : .
  irqchip/sifive-plic: Disable S-mode IRQs if running in M-mode
  irqchip/sifive-plic: Improve naming scheme for per context offsets

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-03-04 14:37:22 +00:00
Marc Zyngier 0c8b522d3e Merge branch irq/qcom-pdc-cleanup into irq/irqchip-next
* irq/qcom-pdc-cleanup:
  : .
  : Spring cleanup for the Qualcomm PDC driver, simplifying its
  : use of irq domains, replacing open-coded functionnalities with
  : the core code equivalent, and fixing the dodgy locking.
  : .
  irqchip/qcom-pdc: Drop open coded version of __assign_bit()
  irqchip/qcom-pdc: Fix broken locking
  irqchip/qcom-pdc: Kill qcom_pdc_translate helper
  irqchip/qcom-pdc: Kill non-wakeup irqdomain
  irqchip/qcom-pdc: Kill PDC_NO_PARENT_IRQ

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-03-01 18:21:38 +00:00
Marc Zyngier d2febf6bbe irqchip/qcom-pdc: Drop open coded version of __assign_bit()
The driver uses what looks like an open-coded version of __assign_bit().
Replace it with the real thing.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Maulik Shah <quic_mkshah@quicinc.com>
Link: https://lore.kernel.org/r/20220224101226.88373-6-maz@kernel.org
2022-03-01 10:06:25 +00:00
Marc Zyngier a6aca2f460 irqchip/qcom-pdc: Fix broken locking
pdc_enable_intr() serves as a primitive to qcom_pdc_gic_{en,dis}able,
and has a raw spinlock for mutual exclusion, which is uses with
interruptible primitives.

This means that this critical section can itself be interrupted.
Should the interrupt also be a PDC interrupt, and the endpoint driver
perform an irq_disable() on that interrupt, we end-up in a deadlock.

Fix this by using the irqsave/irqrestore variants of the locking
primitives.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Maulik Shah <quic_mkshah@quicinc.com>
Link: https://lore.kernel.org/r/20220224101226.88373-5-maz@kernel.org
2022-03-01 10:06:25 +00:00
Marc Zyngier d494d088ac irqchip/qcom-pdc: Kill qcom_pdc_translate helper
qcom_pdc_translate() really is nothing but an open coded version
of irq_domain_translate_twocell(). Get rid of it and use the common
version instead.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Maulik Shah <quic_mkshah@quicinc.com>
Link: https://lore.kernel.org/r/20220224101226.88373-4-maz@kernel.org
2022-03-01 10:06:24 +00:00
Marc Zyngier 4dc70713dc irqchip/qcom-pdc: Kill non-wakeup irqdomain
A careful look at the way the PDC driver works shows that:

- all interrupts are in the same space
- all interrupts are treated the same

And yet the driver creates two domains based on whether
the interrupt gets mapped directly or from the pinctrl code,
which is obviously a waste of resources.

Kill the non-wakeup domain and unify all the interrupt handling.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220224101226.88373-3-maz@kernel.org
2022-03-01 10:06:24 +00:00
Marc Zyngier 8d4c998919 irqchip/qcom-pdc: Kill PDC_NO_PARENT_IRQ
PDC_NO_PARENT_IRQ is pretty pointless, as all it indicates is
that the PDC terminates the interrupt hierarchy. Which is
exactly the same as not having a mapping in the GIC space.
This is also bad practice to treat the absence of a hwirq
as a hwirq itself.

Just explicitly use the region mapping pointer, and drop
the definition.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Maulik Shah <quic_mkshah@quicinc.com>
Link: https://lore.kernel.org/r/20220224101226.88373-2-maz@kernel.org
2022-03-01 10:06:24 +00:00
Marc Zyngier 1a48ce9264 Merge branch kvm-arm64/psci-1.1 into kvmarm-master/next
* kvm-arm64/psci-1.1:
  : .
  : Limited PSCI-1.1 support from Will Deacon:
  :
  : This small series exposes the PSCI SYSTEM_RESET2 call to guests, which
  : allows the propagation of a "reset_type" and a "cookie" back to the VMM.
  : Although Linux guests only ever pass 0 for the type ("SYSTEM_WARM_RESET"),
  : the vendor-defined range can be used by a bootloader to provide additional
  : information about the reset, such as an error code.
  : .
  KVM: arm64: Remove unneeded semicolons
  KVM: arm64: Indicate SYSTEM_RESET2 in kvm_run::system_event flags field
  KVM: arm64: Expose PSCI SYSTEM_RESET2 call to the guest
  KVM: arm64: Bump guest PSCI version to 1.1

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-02-25 13:49:48 +00:00
Marc Zyngier d1e972ace4 gpio: tegra186: Fix chip_data type confusion
The tegra186 GPIO driver makes the assumption that the pointer
returned by irq_data_get_irq_chip_data() is a pointer to a
tegra_gpio structure. Unfortunately, it is actually a pointer
to the inner gpio_chip structure, as mandated by the gpiolib
infrastructure. Nice try.

The saving grace is that the gpio_chip is the first member of
tegra_gpio, so the bug has gone undetected since... forever.

Fix it by performing a container_of() on the pointer. This results
in no additional code, and makes it possible to understand how
the whole thing works.

Fixes: 5b2b135a87 ("gpio: Add Tegra186 support")
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Link: https://lore.kernel.org/r/20220211093904.1112679-1-maz@kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2022-02-19 01:51:24 +01:00
Marc Zyngier 64fd52a4d3 pinctrl: starfive: Use a static name for the GPIO irq_chip
Drop the device name used for the GPIO irq_chip and replace it
with something static. The information is still available from
debugfs and carried as part of the irqdomain.

Suggested-by: Emil Renner Berthing <kernel@esmil.dk>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <brgl@bgdev.pl>
Link: https://lore.kernel.org/r/20220211092345.1093332-1-maz@kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2022-02-19 01:50:23 +01:00
Marc Zyngier 86c12c7386 Merge branch irq/print_chip into irq/irqchip-next
* irq/print_chip:
  : .
  : Convert irqchip drivers that use the .name field as a topology
  : description to the .irq_print_chip callback, which allows the
  : name to be made dymanic. The irq_chip structures are then made
  : 'const' in order to prevent further abuse.
  : .
  irqchip/versatile-fpga: Switch to dynamic chip name output
  irqchip/ts4800: Switch to dynamic chip name output
  irqchip/mvebu-pic: Switch to dynamic chip name output
  irqchip/lpc32xx: Switch to dynamic chip name output
  irqchip/gic: Switch to dynamic chip name output
  genirq/debugfs: Use irq_print_chip() when provided by irqchip
  genirq: Allow irq_chip registration functions to take a const irq_chip
  irqdomain: Let irq_domain_set_{info,hwirq_and_chip} take a const irq_chip

Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-02-15 12:17:50 +00:00
Marc Zyngier 3fb212a042 irqchip/versatile-fpga: Switch to dynamic chip name output
Move the name output to the relevant callback, which allows us
some nice cleanups (mostly owing to the fact that the driver is
now DT only.

We also drop a random include directive from the ftintc010 driver.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220209162607.1118325-8-maz@kernel.org
2022-02-15 11:25:46 +00:00
Marc Zyngier 3344265a26 irqchip/ts4800: Switch to dynamic chip name output
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220209162607.1118325-7-maz@kernel.org
2022-02-15 11:25:46 +00:00
Marc Zyngier 421f16238a irqchip/mvebu-pic: Switch to dynamic chip name output
Instead of overriding the name field, track the corresponding device
and use the relevant callback to output its name.

This allows us to make the irq_chip structure const.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220209162607.1118325-6-maz@kernel.org
2022-02-15 11:25:46 +00:00
Marc Zyngier 365550239f irqchip/lpc32xx: Switch to dynamic chip name output
Instead of overriding the name field with the device name, use
the relevant callback. This allows us to make the irq_chip structure
const.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220209162607.1118325-5-maz@kernel.org
2022-02-15 11:25:46 +00:00
Marc Zyngier 745f1fb91f irqchip/gic: Switch to dynamic chip name output
The last dynamic aspect of the GIC's irq_chip structure is the
name that is associated to it.

Move the output of that name to the relevant callback, which
allows us to do a bit of cleanup and mark the structures const.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220209162607.1118325-4-maz@kernel.org
2022-02-15 11:25:46 +00:00
Marc Zyngier 0a25cb5544 genirq/debugfs: Use irq_print_chip() when provided by irqchip
Since irqchips have the option to implement irq_print_chip, use this
when available to output the irqchip name in debugfs.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220215112154.1360040-1-maz@kernel.org
2022-02-15 11:22:34 +00:00
Marc Zyngier 393e1280f7 genirq: Allow irq_chip registration functions to take a const irq_chip
In order to let a const irqchip be fed to the irqchip layer, adjust
the various prototypes. An extra cast in irq_set_chip()() is required
to avoid a warning.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220209162607.1118325-3-maz@kernel.org
2022-02-15 11:10:21 +00:00
Marc Zyngier 45ec846c1c irqdomain: Let irq_domain_set_{info,hwirq_and_chip} take a const irq_chip
In order to let a const irqchip be fed to the irqchip layer, adjust
the various prototypes. An extra cast in irq_domain_set_hwirq_and_chip()
is required to avoid a warning.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220209162607.1118325-2-maz@kernel.org
2022-02-15 11:10:21 +00:00
Marc Zyngier 5bfa685e62 KVM: arm64: vgic: Read HW interrupt pending state from the HW
It appears that a read access to GIC[DR]_I[CS]PENDRn doesn't always
result in the pending interrupts being accurately reported if they are
mapped to a HW interrupt. This is particularily visible when acking
the timer interrupt and reading the GICR_ISPENDR1 register immediately
after, for example (the interrupt appears as not-pending while it really
is...).

This is because a HW interrupt has its 'active and pending state' kept
in the *physical* distributor, and not in the virtual one, as mandated
by the spec (this is what allows the direct deactivation). The virtual
distributor only caries the pending and active *states* (note the
plural, as these are two independent and non-overlapping states).

Fix it by reading the HW state back, either from the timer itself or
from the distributor if necessary.

Reported-by: Ricardo Koller <ricarkol@google.com>
Tested-by: Ricardo Koller <ricarkol@google.com>
Reviewed-by: Ricardo Koller <ricarkol@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220208123726.3604198-1-maz@kernel.org
2022-02-11 11:01:12 +00:00