aboutsummaryrefslogtreecommitdiff
path: root/arch/arm64/kvm
AgeCommit message (Collapse)Author
2022-03-18KVM: arm64: fix typos in commentsJulia Lawall
Various spelling mistakes in comments. Detected with the help of Coccinelle. Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220318103729.157574-24-Julia.Lawall@inria.fr
2022-03-18KVM: arm64: Generalise VM features into a set of flagsMarc Zyngier
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
2022-03-09Merge branch kvm-arm64/psci-1.1 into kvmarm-master/nextMarc Zyngier
* 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>
2022-03-09KVM: arm64: Really propagate PSCI SYSTEM_RESET2 arguments to userspaceWill Deacon
Commit d43583b890e7 ("KVM: arm64: Expose PSCI SYSTEM_RESET2 call to the guest") hooked up the SYSTEM_RESET2 PSCI call for guests but failed to preserve its arguments for userspace, instead overwriting them with zeroes via smccc_set_retval(). As Linux only passes zeroes for these arguments, this appeared to be working for Linux guests. Oh well. Don't call smccc_set_retval() for a SYSTEM_RESET2 heading to userspace and instead set X0 (and only X0) explicitly to PSCI_RET_INTERNAL_FAILURE just in case the vCPU re-enters the guest. Fixes: d43583b890e7 ("KVM: arm64: Expose PSCI SYSTEM_RESET2 call to the guest") Reported-by: Andrew Walbran <qwandor@google.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220309181308.982-1-will@kernel.org
2022-03-09Merge branch kvm-arm64/misc-5.18 into kvmarm-master/nextMarc Zyngier
* 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>
2022-03-04KVM: arm64: Only open the interrupt window on exit due to an interruptMarc Zyngier
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
2022-02-25Merge branch kvm-arm64/psci-1.1 into kvmarm-master/nextMarc Zyngier
* 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>
2022-02-25KVM: arm64: Remove unneeded semicolonsChangcheng Deng
Fix the following coccicheck review: ./arch/arm64/kvm/psci.c: 379: 3-4: Unneeded semicolon Reported-by: Zeal Robot <zealci@zte.com.cn> Signed-off-by: Changcheng Deng <deng.changcheng@zte.com.cn> [maz: squashed another instance of the same issue in the patch] Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20220223092750.1934130-1-deng.changcheng@zte.com.cn Link: https://lore.kernel.org/r/20220225122922.GA19390@willie-the-truck
2022-02-21KVM: arm64: Indicate SYSTEM_RESET2 in kvm_run::system_event flags fieldWill Deacon
When handling reset and power-off PSCI calls from the guest, we initialise X0 to PSCI_RET_INTERNAL_FAILURE in case the VMM tries to re-run the vCPU after issuing the call. Unfortunately, this also means that the VMM cannot see which PSCI call was issued and therefore cannot distinguish between PSCI SYSTEM_RESET and SYSTEM_RESET2 calls, which is necessary in order to determine the validity of the "reset_type" in X1. Allocate bit 0 of the previously unused 'flags' field of the system_event structure so that we can indicate the PSCI call used to initiate the reset. Cc: Marc Zyngier <maz@kernel.org> Cc: James Morse <james.morse@arm.com> Cc: Alexandru Elisei <alexandru.elisei@arm.com> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220221153524.15397-4-will@kernel.org
2022-02-21KVM: arm64: Expose PSCI SYSTEM_RESET2 call to the guestWill Deacon
PSCI v1.1 introduces the optional SYSTEM_RESET2 call, which allows the caller to provide a vendor-specific "reset type" and "cookie" to request a particular form of reset or shutdown. Expose this call to the guest and handle it in the same way as PSCI SYSTEM_RESET, along with some basic range checking on the type argument. Cc: Marc Zyngier <maz@kernel.org> Cc: James Morse <james.morse@arm.com> Cc: Alexandru Elisei <alexandru.elisei@arm.com> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220221153524.15397-3-will@kernel.org
2022-02-21KVM: arm64: Bump guest PSCI version to 1.1Will Deacon
Expose PSCI version v1.1 to the guest by default. The only difference for now is that an updated version number is reported by PSCI_VERSION. Cc: Marc Zyngier <maz@kernel.org> Cc: James Morse <james.morse@arm.com> Cc: Alexandru Elisei <alexandru.elisei@arm.com> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220221153524.15397-2-will@kernel.org
2022-02-08Merge branch kvm-arm64/pmu-bl into kvmarm-master/nextMarc Zyngier
* kvm-arm64/pmu-bl: : . : Improve PMU support on heterogeneous systems, courtesy of Alexandru Elisei : . KVM: arm64: Refuse to run VCPU if the PMU doesn't match the physical CPU KVM: arm64: Add KVM_ARM_VCPU_PMU_V3_SET_PMU attribute KVM: arm64: Keep a list of probed PMUs KVM: arm64: Keep a per-VM pointer to the default PMU perf: Fix wrong name in comment for struct perf_cpu_context KVM: arm64: Do not change the PMU event filter after a VCPU has run Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-02-08KVM: arm64: Refuse to run VCPU if the PMU doesn't match the physical CPUAlexandru Elisei
Userspace can assign a PMU to a VCPU with the KVM_ARM_VCPU_PMU_V3_SET_PMU device ioctl. If the VCPU is scheduled on a physical CPU which has a different PMU, the perf events needed to emulate a guest PMU won't be scheduled in and the guest performance counters will stop counting. Treat it as an userspace error and refuse to run the VCPU in this situation. Suggested-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220127161759.53553-7-alexandru.elisei@arm.com
2022-02-08KVM: arm64: Add KVM_ARM_VCPU_PMU_V3_SET_PMU attributeAlexandru Elisei
When KVM creates an event and there are more than one PMUs present on the system, perf_init_event() will go through the list of available PMUs and will choose the first one that can create the event. The order of the PMUs in this list depends on the probe order, which can change under various circumstances, for example if the order of the PMU nodes change in the DTB or if asynchronous driver probing is enabled on the kernel command line (with the driver_async_probe=armv8-pmu option). Another consequence of this approach is that on heteregeneous systems all virtual machines that KVM creates will use the same PMU. This might cause unexpected behaviour for userspace: when a VCPU is executing on the physical CPU that uses this default PMU, PMU events in the guest work correctly; but when the same VCPU executes on another CPU, PMU events in the guest will suddenly stop counting. Fortunately, perf core allows user to specify on which PMU to create an event by using the perf_event_attr->type field, which is used by perf_init_event() as an index in the radix tree of available PMUs. Add the KVM_ARM_VCPU_PMU_V3_CTRL(KVM_ARM_VCPU_PMU_V3_SET_PMU) VCPU attribute to allow userspace to specify the arm_pmu that KVM will use when creating events for that VCPU. KVM will make no attempt to run the VCPU on the physical CPUs that share the PMU, leaving it up to userspace to manage the VCPU threads' affinity accordingly. To ensure that KVM doesn't expose an asymmetric system to the guest, the PMU set for one VCPU will be used by all other VCPUs. Once a VCPU has run, the PMU cannot be changed in order to avoid changing the list of available events for a VCPU, or to change the semantics of existing events. Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220127161759.53553-6-alexandru.elisei@arm.com
2022-02-08KVM: arm64: Keep a list of probed PMUsAlexandru Elisei
The ARM PMU driver calls kvm_host_pmu_init() after probing to tell KVM that a hardware PMU is available for guest emulation. Heterogeneous systems can have more than one PMU present, and the callback gets called multiple times, once for each of them. Keep track of all the PMUs available to KVM, as they're going to be needed later. Reviewed-by: Reiji Watanabe <reijiw@google.com> Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220127161759.53553-5-alexandru.elisei@arm.com
2022-02-08KVM: arm64: Keep a per-VM pointer to the default PMUMarc Zyngier
As we are about to allow selection of the PMU exposed to a guest, start by keeping track of the default one instead of only the PMU version. Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> Link: https://lore.kernel.org/r/20220127161759.53553-4-alexandru.elisei@arm.com
2022-02-08KVM: arm64: Do not change the PMU event filter after a VCPU has runMarc Zyngier
Userspace can specify which events a guest is allowed to use with the KVM_ARM_VCPU_PMU_V3_FILTER attribute. The list of allowed events can be identified by a guest from reading the PMCEID{0,1}_EL0 registers. Changing the PMU event filter after a VCPU has run can cause reads of the registers performed before the filter is changed to return different values than reads performed with the new event filter in place. The architecture defines the two registers as read-only, and this behaviour contradicts that. Keep track when the first VCPU has run and deny changes to the PMU event filter to prevent this from happening. Signed-off-by: Marc Zyngier <maz@kernel.org> [ Alexandru E: Added commit message, updated ioctl documentation ] Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220127161759.53553-2-alexandru.elisei@arm.com
2022-02-08Merge branch kvm-arm64/misc-5.18 into kvmarm-master/nextMarc Zyngier
* 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 : . KVM: arm64: pkvm: Implement CONFIG_DEBUG_LIST at EL2 KVM: arm64: Drop unused param from kvm_psci_version() Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-02-08KVM: arm64: pkvm: Implement CONFIG_DEBUG_LIST at EL2Keir Fraser
Currently the check functions are stubbed out at EL2. Implement versions suitable for the constrained EL2 environment. Signed-off-by: Keir Fraser <keirf@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220131124114.3103337-1-keirf@google.com
2022-02-08KVM: arm64: Drop unused param from kvm_psci_version()Oliver Upton
kvm_psci_version() consumes a pointer to struct kvm in addition to a vcpu pointer. Drop the kvm pointer as it is unused. While the comment suggests the explicit kvm pointer was useful for calling from hyp, there exist no such callsite in hyp. Signed-off-by: Oliver Upton <oupton@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220208012705.640444-1-oupton@google.com
2022-02-08Merge branch kvm-arm64/vmid-allocator into kvmarm-master/nextMarc Zyngier
* kvm-arm64/vmid-allocator: : . : VMID allocation rewrite from Shameerali Kolothum Thodi, paving the : way for pinned VMIDs and SVA. : . KVM: arm64: Make active_vmids invalid on vCPU schedule out KVM: arm64: Align the VMID allocation with the arm64 ASID KVM: arm64: Make VMID bits accessible outside of allocator KVM: arm64: Introduce a new VMID allocator for KVM Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-02-08KVM: arm64: Make active_vmids invalid on vCPU schedule outShameer Kolothum
Like ASID allocator, we copy the active_vmids into the reserved_vmids on a rollover. But it's unlikely that every CPU will have a vCPU as current task and we may end up unnecessarily reserving the VMID space. Hence, set active_vmids to an invalid one when scheduling out a vCPU. Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211122121844.867-5-shameerali.kolothum.thodi@huawei.com
2022-02-08KVM: arm64: Align the VMID allocation with the arm64 ASIDJulien Grall
At the moment, the VMID algorithm will send an SGI to all the CPUs to force an exit and then broadcast a full TLB flush and I-Cache invalidation. This patch uses the new VMID allocator. The benefits are:    - Aligns with arm64 ASID algorithm.    - CPUs are not forced to exit at roll-over. Instead, the VMID will be marked reserved and context invalidation is broadcasted. This will reduce the IPIs traffic.   - More flexible to add support for pinned KVM VMIDs in the future.     With the new algo, the code is now adapted:     - The call to update_vmid() will be done with preemption disabled as the new algo requires to store information per-CPU. Signed-off-by: Julien Grall <julien.grall@arm.com> Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211122121844.867-4-shameerali.kolothum.thodi@huawei.com
2022-02-08KVM: arm64: Make VMID bits accessible outside of allocatorShameer Kolothum
Since we already set the kvm_arm_vmid_bits in the VMID allocator init function, make it accessible outside as well so that it can be used in the subsequent patch. Suggested-by: Will Deacon <will@kernel.org> Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211122121844.867-3-shameerali.kolothum.thodi@huawei.com
2022-02-08KVM: arm64: Introduce a new VMID allocator for KVMShameer Kolothum
A new VMID allocator for arm64 KVM use. This is based on arm64 ASID allocator algorithm. One major deviation from the ASID allocator is the way we flush the context. Unlike ASID allocator, we expect less frequent rollover in the case of VMIDs. Hence, instead of marking the CPU as flush_pending and issuing a local context invalidation on the next context switch, we  broadcast TLB flush + I-cache invalidation over the inner shareable domain on rollover. Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20211122121844.867-2-shameerali.kolothum.thodi@huawei.com
2022-02-08Merge branch kvm-arm64/fpsimd-doc into kvmarm-master/nextMarc Zyngier
* kvm-arm64/fpsimd-doc: : . : FPSIMD documentation update, courtesy of Mark Brown : . arm64/fpsimd: Clarify the purpose of using last in fpsimd_save() KVM: arm64: Add some more comments in kvm_hyp_handle_fpsimd() KVM: arm64: Add comments for context flush and sync callbacks Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-02-08KVM: arm64: Add some more comments in kvm_hyp_handle_fpsimd()Mark Brown
The handling for FPSIMD/SVE traps is multi stage and involves some trap manipulation which isn't quite so immediately obvious as might be desired so add a few more comments. Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220124155720.3943374-3-broonie@kernel.org
2022-02-08KVM: arm64: Add comments for context flush and sync callbacksMark Brown
Add a little bit of information on where _ctxflush_fp() and _ctxsync_fp() are called to help people unfamiliar with the code get up to speed. Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220124155720.3943374-2-broonie@kernel.org
2022-02-08Merge branch kvm-arm64/mmu-rwlock into kvmarm-master/nextMarc Zyngier
* kvm-arm64/mmu-rwlock: : . : MMU locking optimisations from Jing Zhang, allowing permission : relaxations to occur in parallel. : . KVM: selftests: Add vgic initialization for dirty log perf test for ARM KVM: arm64: Add fast path to handle permission relaxation during dirty logging KVM: arm64: Use read/write spin lock for MMU protection Signed-off-by: Marc Zyngier <maz@kernel.org>
2022-02-08KVM: arm64: Add fast path to handle permission relaxation during dirty loggingJing Zhang
To reduce MMU lock contention during dirty logging, all permission relaxation operations would be performed under read lock. Signed-off-by: Jing Zhang <jingzhangos@google.com> Tested-by: Fuad Tabba <tabba@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220118015703.3630552-3-jingzhangos@google.com
2022-02-08KVM: arm64: Use read/write spin lock for MMU protectionJing Zhang
Replace MMU spinlock with rwlock and update all instances of the lock being acquired with a write lock acquisition. Future commit will add a fast path for permission relaxation during dirty logging under a read lock. Signed-off-by: Jing Zhang <jingzhangos@google.com> Tested-by: Fuad Tabba <tabba@google.com> Reviewed-by: Fuad Tabba <tabba@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220118015703.3630552-2-jingzhangos@google.com
2022-02-08KVM: arm64: Emulate the OS LockOliver Upton
The OS lock blocks all debug exceptions at every EL. To date, KVM has not implemented the OS lock for its guests, despite the fact that it is mandatory per the architecture. Simple context switching between the guest and host is not appropriate, as its effects are not constrained to the guest context. Emulate the OS Lock by clearing MDE and SS in MDSCR_EL1, thereby blocking all but software breakpoint instructions. Signed-off-by: Oliver Upton <oupton@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220203174159.2887882-5-oupton@google.com
2022-02-08KVM: arm64: Allow guest to set the OSLK bitOliver Upton
Allow writes to OSLAR and forward the OSLK bit to OSLSR. Do nothing with the value for now. Reviewed-by: Reiji Watanabe <reijiw@google.com> Signed-off-by: Oliver Upton <oupton@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220203174159.2887882-4-oupton@google.com
2022-02-08KVM: arm64: Stash OSLSR_EL1 in the cpu contextOliver Upton
An upcoming change to KVM will emulate the OS Lock from the PoV of the guest. Add OSLSR_EL1 to the cpu context and handle reads using the stored value. Define some mnemonics for for handling the OSLM field and use them to make the reset value of OSLSR_EL1 more readable. Wire up a custom handler for writes from userspace and prevent any of the invariant bits from changing. Note that the OSLK bit is not invariant and will be made writable by the aforementioned change. Reviewed-by: Reiji Watanabe <reijiw@google.com> Signed-off-by: Oliver Upton <oupton@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220203174159.2887882-3-oupton@google.com
2022-02-08KVM: arm64: Correctly treat writes to OSLSR_EL1 as undefinedOliver Upton
Writes to OSLSR_EL1 are UNDEFINED and should never trap from EL1 to EL2, but the kvm trap handler for OSLSR_EL1 handles writes via ignore_write(). This is confusing to readers of code, but should have no functional impact. For clarity, use write_to_read_only() rather than ignore_write(). If a trap is unexpectedly taken to EL2 in violation of the architecture, this will WARN_ONCE() and inject an undef into the guest. Reviewed-by: Reiji Watanabe <reijiw@google.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> [adopted Mark's changelog suggestion, thanks!] Signed-off-by: Oliver Upton <oupton@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220203174159.2887882-2-oupton@google.com
2022-02-05Merge tag 'kvmarm-fixes-5.17-2' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 5.17, take #2 - A couple of fixes when handling an exception while a SError has been delivered - Workaround for Cortex-A510's single-step[ erratum
2022-02-03KVM: arm64: Workaround Cortex-A510's single-step and PAC trap errataJames Morse
Cortex-A510's erratum #2077057 causes SPSR_EL2 to be corrupted when single-stepping authenticated ERET instructions. A single step is expected, but a pointer authentication trap is taken instead. The erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow EL1 to cause a return to EL2 with a guest controlled ELR_EL2. Because the conditions require an ERET into active-not-pending state, this is only a problem for the EL2 when EL2 is stepping EL1. In this case the previous SPSR_EL2 value is preserved in struct kvm_vcpu, and can be restored. Cc: stable@vger.kernel.org # 53960faf2b73: arm64: Add Cortex-A510 CPU part definition Cc: stable@vger.kernel.org Signed-off-by: James Morse <james.morse@arm.com> [maz: fixup cpucaps ordering] Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220127122052.1584324-5-james.morse@arm.com
2022-02-03KVM: arm64: Stop handle_exit() from handling HVC twice when an SError occursJames Morse
Prior to commit defe21f49bc9 ("KVM: arm64: Move PC rollback on SError to HYP"), when an SError is synchronised due to another exception, KVM handles the SError first. If the guest survives, the instruction that triggered the original exception is re-exectued to handle the first exception. HVC is treated as a special case as the instruction wouldn't normally be re-exectued, as its not a trap. Commit defe21f49bc9 didn't preserve the behaviour of the 'return 1' that skips the rest of handle_exit(). Since commit defe21f49bc9, KVM will try to handle the SError and the original exception at the same time. When the exception was an HVC, fixup_guest_exit() has already rolled back ELR_EL2, meaning if the guest has virtual SError masked, it will execute and handle the HVC twice. Restore the original behaviour. Fixes: defe21f49bc9 ("KVM: arm64: Move PC rollback on SError to HYP") Cc: stable@vger.kernel.org Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220127122052.1584324-4-james.morse@arm.com
2022-02-03KVM: arm64: Avoid consuming a stale esr value when SError occurJames Morse
When any exception other than an IRQ occurs, the CPU updates the ESR_EL2 register with the exception syndrome. An SError may also become pending, and will be synchronised by KVM. KVM notes the exception type, and whether an SError was synchronised in exit_code. When an exception other than an IRQ occurs, fixup_guest_exit() updates vcpu->arch.fault.esr_el2 from the hardware register. When an SError was synchronised, the vcpu esr value is used to determine if the exception was due to an HVC. If so, ELR_EL2 is moved back one instruction. This is so that KVM can process the SError first, and re-execute the HVC if the guest survives the SError. But if an IRQ synchronises an SError, the vcpu's esr value is stale. If the previous non-IRQ exception was an HVC, KVM will corrupt ELR_EL2, causing an unrelated guest instruction to be executed twice. Check ARM_EXCEPTION_CODE() before messing with ELR_EL2, IRQs don't update this register so don't need to check. Fixes: defe21f49bc9 ("KVM: arm64: Move PC rollback on SError to HYP") Cc: stable@vger.kernel.org Reported-by: Steven Price <steven.price@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220127122052.1584324-3-james.morse@arm.com
2022-02-01kvm/arm64: rework guest entry logicMark Rutland
In kvm_arch_vcpu_ioctl_run() we enter an RCU extended quiescent state (EQS) by calling guest_enter_irqoff(), and unmasked IRQs prior to exiting the EQS by calling guest_exit(). As the IRQ entry code will not wake RCU in this case, we may run the core IRQ code and IRQ handler without RCU watching, leading to various potential problems. Additionally, we do not inform lockdep or tracing that interrupts will be enabled during guest execution, which caan lead to misleading traces and warnings that interrupts have been enabled for overly-long periods. This patch fixes these issues by using the new timing and context entry/exit helpers to ensure that interrupts are handled during guest vtime but with RCU watching, with a sequence: guest_timing_enter_irqoff(); guest_state_enter_irqoff(); < run the vcpu > guest_state_exit_irqoff(); < take any pending IRQs > guest_timing_exit_irqoff(); Since instrumentation may make use of RCU, we must also ensure that no instrumented code is run during the EQS. I've split out the critical section into a new kvm_arm_enter_exit_vcpu() helper which is marked noinstr. Fixes: 1b3d546daf85ed2b ("arm/arm64: KVM: Properly account for guest CPU time") Reported-by: Nicolas Saenz Julienne <nsaenzju@redhat.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Nicolas Saenz Julienne <nsaenzju@redhat.com> Cc: Alexandru Elisei <alexandru.elisei@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: James Morse <james.morse@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Will Deacon <will@kernel.org> Message-Id: <20220201132926.3301912-3-mark.rutland@arm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-28Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm fixes from Paolo Bonzini: "Two larger x86 series: - Redo incorrect fix for SEV/SMAP erratum - Windows 11 Hyper-V workaround Other x86 changes: - Various x86 cleanups - Re-enable access_tracking_perf_test - Fix for #GP handling on SVM - Fix for CPUID leaf 0Dh in KVM_GET_SUPPORTED_CPUID - Fix for ICEBP in interrupt shadow - Avoid false-positive RCU splat - Enable Enlightened MSR-Bitmap support for real ARM: - Correctly update the shadow register on exception injection when running in nVHE mode - Correctly use the mm_ops indirection when performing cache invalidation from the page-table walker - Restrict the vgic-v3 workaround for SEIS to the two known broken implementations Generic code changes: - Dead code cleanup" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (43 commits) KVM: eventfd: Fix false positive RCU usage warning KVM: nVMX: Allow VMREAD when Enlightened VMCS is in use KVM: nVMX: Implement evmcs_field_offset() suitable for handle_vmread() KVM: nVMX: Rename vmcs_to_field_offset{,_table} KVM: nVMX: eVMCS: Filter out VM_EXIT_SAVE_VMX_PREEMPTION_TIMER KVM: nVMX: Also filter MSR_IA32_VMX_TRUE_PINBASED_CTLS when eVMCS selftests: kvm: check dynamic bits against KVM_X86_XCOMP_GUEST_SUPP KVM: x86: add system attribute to retrieve full set of supported xsave states KVM: x86: Add a helper to retrieve userspace address from kvm_device_attr selftests: kvm: move vm_xsave_req_perm call to amx_test KVM: x86: Sync the states size with the XCR0/IA32_XSS at, any time KVM: x86: Update vCPU's runtime CPUID on write to MSR_IA32_XSS KVM: x86: Keep MSR_IA32_XSS unchanged for INIT KVM: x86: Free kvm_cpuid_entry2 array on post-KVM_RUN KVM_SET_CPUID{,2} KVM: nVMX: WARN on any attempt to allocate shadow VMCS for vmcs02 KVM: selftests: Don't skip L2's VMCALL in SMM test for SVM guest KVM: x86: Check .flags in kvm_cpuid_check_equal() too KVM: x86: Forcibly leave nested virt when SMM state is toggled KVM: SVM: drop unnecessary code in svm_hv_vmcb_dirty_nested_enlightenments() KVM: SVM: hyper-v: Enable Enlightened MSR-Bitmap support for real ...
2022-01-28Merge tag 'kvmarm-fixes-5.17-1' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 5.17, take #1 - Correctly update the shadow register on exception injection when running in nVHE mode - Correctly use the mm_ops indirection when performing cache invalidation from the page-table walker - Restrict the vgic-v3 workaround for SEIS to the two known broken implementations
2022-01-24KVM: arm64: Use shadow SPSR_EL1 when injecting exceptions on !VHEMarc Zyngier
Injecting an exception into a guest with non-VHE is risky business. Instead of writing in the shadow register for the switch code to restore it, we override the CPU register instead. Which gets overriden a few instructions later by said restore code. The result is that although the guest correctly gets the exception, it will return to the original context in some random state, depending on what was there the first place... Boo. Fix the issue by writing to the shadow register. The original code is absolutely fine on VHE, as the state is already loaded, and writing to the shadow register in that case would actually be a bug. Fixes: bb666c472ca2 ("KVM: arm64: Inject AArch64 exceptions from HYP") Cc: stable@vger.kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org> Reviewed-by: Fuad Tabba <tabba@google.com> Link: https://lore.kernel.org/r/20220121184207.423426-1-maz@kernel.org
2022-01-22KVM: arm64: vgic-v3: Restrict SEIS workaround to known broken systemsMarc Zyngier
Contrary to what df652bcf1136 ("KVM: arm64: vgic-v3: Work around GICv3 locally generated SErrors") was asserting, there is at least one other system out there (Cavium ThunderX2) implementing SEIS, and not in an obviously broken way. So instead of imposing the M1 workaround on an innocent bystander, let's limit it to the two known broken Apple implementations. Fixes: df652bcf1136 ("KVM: arm64: vgic-v3: Work around GICv3 locally generated SErrors") Reported-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20220122103912.795026-1-maz@kernel.org
2022-01-16Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "RISCV: - Use common KVM implementation of MMU memory caches - SBI v0.2 support for Guest - Initial KVM selftests support - Fix to avoid spurious virtual interrupts after clearing hideleg CSR - Update email address for Anup and Atish ARM: - Simplification of the 'vcpu first run' by integrating it into KVM's 'pid change' flow - Refactoring of the FP and SVE state tracking, also leading to a simpler state and less shared data between EL1 and EL2 in the nVHE case - Tidy up the header file usage for the nvhe hyp object - New HYP unsharing mechanism, finally allowing pages to be unmapped from the Stage-1 EL2 page-tables - Various pKVM cleanups around refcounting and sharing - A couple of vgic fixes for bugs that would trigger once the vcpu xarray rework is merged, but not sooner - Add minimal support for ARMv8.7's PMU extension - Rework kvm_pgtable initialisation ahead of the NV work - New selftest for IRQ injection - Teach selftests about the lack of default IPA space and page sizes - Expand sysreg selftest to deal with Pointer Authentication - The usual bunch of cleanups and doc update s390: - fix sigp sense/start/stop/inconsistency - cleanups x86: - Clean up some function prototypes more - improved gfn_to_pfn_cache with proper invalidation, used by Xen emulation - add KVM_IRQ_ROUTING_XEN_EVTCHN and event channel delivery - completely remove potential TOC/TOU races in nested SVM consistency checks - update some PMCs on emulated instructions - Intel AMX support (joint work between Thomas and Intel) - large MMU cleanups - module parameter to disable PMU virtualization - cleanup register cache - first part of halt handling cleanups - Hyper-V enlightened MSR bitmap support for nested hypervisors Generic: - clean up Makefiles - introduce CONFIG_HAVE_KVM_DIRTY_RING - optimize memslot lookup using a tree - optimize vCPU array usage by converting to xarray" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (268 commits) x86/fpu: Fix inline prefix warnings selftest: kvm: Add amx selftest selftest: kvm: Move struct kvm_x86_state to header selftest: kvm: Reorder vcpu_load_state steps for AMX kvm: x86: Disable interception for IA32_XFD on demand x86/fpu: Provide fpu_sync_guest_vmexit_xfd_state() kvm: selftests: Add support for KVM_CAP_XSAVE2 kvm: x86: Add support for getting/setting expanded xstate buffer x86/fpu: Add uabi_size to guest_fpu kvm: x86: Add CPUID support for Intel AMX kvm: x86: Add XCR0 support for Intel AMX kvm: x86: Disable RDMSR interception of IA32_XFD_ERR kvm: x86: Emulate IA32_XFD_ERR for guest kvm: x86: Intercept #NM for saving IA32_XFD_ERR x86/fpu: Prepare xfd_err in struct fpu_guest kvm: x86: Add emulation for IA32_XFD x86/fpu: Provide fpu_update_guest_xfd() for IA32_XFD emulation kvm: x86: Enable dynamic xfeatures at KVM_SET_CPUID2 x86/fpu: Provide fpu_enable_guest_xfd_features() for KVM x86/fpu: Add guest support to xfd_enable_feature() ...
2022-01-14KVM: arm64: pkvm: Use the mm_ops indirection for cache maintenanceMarc Zyngier
CMOs issued from EL2 cannot directly use the kernel helpers, as EL2 doesn't have a mapping of the guest pages. Oops. Instead, use the mm_ops indirection to use helpers that will perform a mapping at EL2 and allow the CMO to be effective. Fixes: 25aa28691bb9 ("KVM: arm64: Move guest CMOs to the fault handlers") Reviewed-by: Quentin Perret <qperret@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220114125038.1336965-1-maz@kernel.org
2022-01-12Merge tag 'perf_core_for_v5.17_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Borislav Petkov: "Cleanup of the perf/kvm interaction." * tag 'perf_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf: Drop guest callback (un)register stubs KVM: arm64: Drop perf.c and fold its tiny bits of code into arm.c KVM: arm64: Hide kvm_arm_pmu_available behind CONFIG_HW_PERF_EVENTS=y KVM: arm64: Convert to the generic perf callbacks KVM: x86: Move Intel Processor Trace interrupt handler to vmx.c KVM: Move x86's perf guest info callbacks to generic KVM KVM: x86: More precisely identify NMI from guest when handling PMI KVM: x86: Drop current_vcpu for kvm_running_vcpu + kvm_arch_vcpu variable perf/core: Use static_call to optimize perf_guest_info_callbacks perf: Force architectures to opt-in to guest callbacks perf: Add wrappers for invoking guest callbacks perf/core: Rework guest callbacks to prepare for static_call support perf: Drop dead and useless guest "support" from arm, csky, nds32 and riscv perf: Stop pretending that perf can handle multiple guest callbacks KVM: x86: Register Processor Trace interrupt hook iff PT enabled in guest KVM: x86: Register perf callbacks after calling vendor's hardware_setup() perf: Protect perf_guest_cbs with RCU
2022-01-10Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: - KCSAN enabled for arm64. - Additional kselftests to exercise the syscall ABI w.r.t. SVE/FPSIMD. - Some more SVE clean-ups and refactoring in preparation for SME support (scalable matrix extensions). - BTI clean-ups (SYM_FUNC macros etc.) - arm64 atomics clean-up and codegen improvements. - HWCAPs for FEAT_AFP (alternate floating point behaviour) and FEAT_RPRESS (increased precision of reciprocal estimate and reciprocal square root estimate). - Use SHA3 instructions to speed-up XOR. - arm64 unwind code refactoring/unification. - Avoid DC (data cache maintenance) instructions when DCZID_EL0.DZP == 1 (potentially set by a hypervisor; user-space already does this). - Perf updates for arm64: support for CI-700, HiSilicon PCIe PMU, Marvell CN10K LLC-TAD PMU, miscellaneous clean-ups. - Other fixes and clean-ups; highlights: fix the handling of erratum 1418040, correct the calculation of the nomap region boundaries, introduce io_stop_wc() mapped to the new DGH instruction (data gathering hint). * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (81 commits) arm64: Use correct method to calculate nomap region boundaries arm64: Drop outdated links in comments arm64: perf: Don't register user access sysctl handler multiple times drivers: perf: marvell_cn10k: fix an IS_ERR() vs NULL check perf/smmuv3: Fix unused variable warning when CONFIG_OF=n arm64: errata: Fix exec handling in erratum 1418040 workaround arm64: Unhash early pointer print plus improve comment asm-generic: introduce io_stop_wc() and add implementation for ARM64 arm64: Ensure that the 'bti' macro is defined where linkage.h is included arm64: remove __dma_*_area() aliases docs/arm64: delete a space from tagged-address-abi arm64: Enable KCSAN kselftest/arm64: Add pidbench for floating point syscall cases arm64/fp: Add comments documenting the usage of state restore functions kselftest/arm64: Add a test program to exercise the syscall ABI kselftest/arm64: Allow signal tests to trigger from a function kselftest/arm64: Parameterise ptrace vector length information arm64/sve: Minor clarification of ABI documentation arm64/sve: Generalise vector length configuration prctl() for SME arm64/sve: Make sysctl interface for SVE reusable by SME ...
2022-01-07Merge tag 'kvmarm-5.17' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 updates for Linux 5.16 - Simplification of the 'vcpu first run' by integrating it into KVM's 'pid change' flow - Refactoring of the FP and SVE state tracking, also leading to a simpler state and less shared data between EL1 and EL2 in the nVHE case - Tidy up the header file usage for the nvhe hyp object - New HYP unsharing mechanism, finally allowing pages to be unmapped from the Stage-1 EL2 page-tables - Various pKVM cleanups around refcounting and sharing - A couple of vgic fixes for bugs that would trigger once the vcpu xarray rework is merged, but not sooner - Add minimal support for ARMv8.7's PMU extension - Rework kvm_pgtable initialisation ahead of the NV work - New selftest for IRQ injection - Teach selftests about the lack of default IPA space and page sizes - Expand sysreg selftest to deal with Pointer Authentication - The usual bunch of cleanups and doc update
2022-01-05Merge branches 'for-next/misc', 'for-next/cache-ops-dzp', ↵Catalin Marinas
'for-next/stacktrace', 'for-next/xor-neon', 'for-next/kasan', 'for-next/armv8_7-fp', 'for-next/atomics', 'for-next/bti', 'for-next/sve', 'for-next/kselftest' and 'for-next/kcsan', remote-tracking branch 'arm64/for-next/perf' into for-next/core * arm64/for-next/perf: (32 commits) arm64: perf: Don't register user access sysctl handler multiple times drivers: perf: marvell_cn10k: fix an IS_ERR() vs NULL check perf/smmuv3: Fix unused variable warning when CONFIG_OF=n arm64: perf: Support new DT compatibles arm64: perf: Simplify registration boilerplate arm64: perf: Support Denver and Carmel PMUs drivers/perf: hisi: Add driver for HiSilicon PCIe PMU docs: perf: Add description for HiSilicon PCIe PMU driver dt-bindings: perf: Add YAML schemas for Marvell CN10K LLC-TAD pmu bindings drivers: perf: Add LLC-TAD perf counter support perf/smmuv3: Synthesize IIDR from CoreSight ID registers perf/smmuv3: Add devicetree support dt-bindings: Add Arm SMMUv3 PMCG binding perf/arm-cmn: Add debugfs topology info perf/arm-cmn: Add CI-700 Support dt-bindings: perf: arm-cmn: Add CI-700 perf/arm-cmn: Support new IP features perf/arm-cmn: Demarcate CMN-600 specifics perf/arm-cmn: Move group validation data off-stack perf/arm-cmn: Optimise DTC counter accesses ... * for-next/misc: : Miscellaneous patches arm64: Use correct method to calculate nomap region boundaries arm64: Drop outdated links in comments arm64: errata: Fix exec handling in erratum 1418040 workaround arm64: Unhash early pointer print plus improve comment asm-generic: introduce io_stop_wc() and add implementation for ARM64 arm64: remove __dma_*_area() aliases docs/arm64: delete a space from tagged-address-abi arm64/fp: Add comments documenting the usage of state restore functions arm64: mm: Use asid feature macro for cheanup arm64: mm: Rename asid2idx() to ctxid2asid() arm64: kexec: reduce calls to page_address() arm64: extable: remove unused ex_handler_t definition arm64: entry: Use SDEI event constants arm64: Simplify checking for populated DT arm64/kvm: Fix bitrotted comment for SVE handling in handle_exit.c * for-next/cache-ops-dzp: : Avoid DC instructions when DCZID_EL0.DZP == 1 arm64: mte: DC {GVA,GZVA} shouldn't be used when DCZID_EL0.DZP == 1 arm64: clear_page() shouldn't use DC ZVA when DCZID_EL0.DZP == 1 * for-next/stacktrace: : Unify the arm64 unwind code arm64: Make some stacktrace functions private arm64: Make dump_backtrace() use arch_stack_walk() arm64: Make profile_pc() use arch_stack_walk() arm64: Make return_address() use arch_stack_walk() arm64: Make __get_wchan() use arch_stack_walk() arm64: Make perf_callchain_kernel() use arch_stack_walk() arm64: Mark __switch_to() as __sched arm64: Add comment for stack_info::kr_cur arch: Make ARCH_STACKWALK independent of STACKTRACE * for-next/xor-neon: : Use SHA3 instructions to speed up XOR arm64/xor: use EOR3 instructions when available * for-next/kasan: : Log potential KASAN shadow aliases arm64: mm: log potential KASAN shadow alias arm64: mm: use die_kernel_fault() in do_mem_abort() * for-next/armv8_7-fp: : Add HWCAPS for ARMv8.7 FEAT_AFP amd FEAT_RPRES arm64: cpufeature: add HWCAP for FEAT_RPRES arm64: add ID_AA64ISAR2_EL1 sys register arm64: cpufeature: add HWCAP for FEAT_AFP * for-next/atomics: : arm64 atomics clean-ups and codegen improvements arm64: atomics: lse: define RETURN ops in terms of FETCH ops arm64: atomics: lse: improve constraints for simple ops arm64: atomics: lse: define ANDs in terms of ANDNOTs arm64: atomics lse: define SUBs in terms of ADDs arm64: atomics: format whitespace consistently * for-next/bti: : BTI clean-ups arm64: Ensure that the 'bti' macro is defined where linkage.h is included arm64: Use BTI C directly and unconditionally arm64: Unconditionally override SYM_FUNC macros arm64: Add macro version of the BTI instruction arm64: ftrace: add missing BTIs arm64: kexec: use __pa_symbol(empty_zero_page) arm64: update PAC description for kernel * for-next/sve: : SVE code clean-ups and refactoring in prepararation of Scalable Matrix Extensions arm64/sve: Minor clarification of ABI documentation arm64/sve: Generalise vector length configuration prctl() for SME arm64/sve: Make sysctl interface for SVE reusable by SME * for-next/kselftest: : arm64 kselftest additions kselftest/arm64: Add pidbench for floating point syscall cases kselftest/arm64: Add a test program to exercise the syscall ABI kselftest/arm64: Allow signal tests to trigger from a function kselftest/arm64: Parameterise ptrace vector length information * for-next/kcsan: : Enable KCSAN for arm64 arm64: Enable KCSAN