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2020-05-16KVM: arm64: Move virt/kvm/arm to arch/arm64Marc Zyngier1-564/+0
Now that the 32bit KVM/arm host is a distant memory, let's move the whole of the KVM/arm64 code into the arm64 tree. As they said in the song: Welcome Home (Sanitarium). Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20200513104034.74741-1-maz@kernel.org
2020-04-17KVM: arm64: PSCI: Forbid 64bit functions for 32bit guestsMarc Zyngier1-0/+24
Implementing (and even advertising) 64bit PSCI functions to 32bit guests is at least a bit odd, if not altogether violating the spec which says ("5.2.1 Register usage in arguments and return values"): "Adherence to the SMC Calling Conventions implies that any AArch32 caller of an SMC64 function will get a return code of 0xFFFFFFFF(int32). This matches the NOT_SUPPORTED error code used in PSCI" Tighten the implementation by pretending these functions are not there for 32bit guests. Reviewed-by: Christoffer Dall <christoffer.dall@arm.com> Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-04-17KVM: arm64: PSCI: Narrow input registers when using 32bit functionsMarc Zyngier1-0/+16
When a guest delibarately uses an SMC32 function number (which is allowed), we should make sure we drop the top 32bits from the input arguments, as they could legitimately be junk. Reported-by: Christoffer Dall <christoffer.dall@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@arm.com> Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-03-16KVM: Remove unnecessary asm/kvm_host.h includesPeter Xu1-1/+0
Remove includes of asm/kvm_host.h from files that already include linux/kvm_host.h to make it more obvious that there is no ordering issue between the two headers. linux/kvm_host.h includes asm/kvm_host.h to pick up architecture specific settings, and this will never change, i.e. including asm/kvm_host.h after linux/kvm_host.h may seem problematic, but in practice is simply redundant. Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-10-21KVM: arm/arm64: Factor out hypercall handling from PSCI codeChristoffer Dall1-82/+2
We currently intertwine the KVM PSCI implementation with the general dispatch of hypercall handling, which makes perfect sense because PSCI is the only category of hypercalls we support. However, as we are about to support additional hypercalls, factor out this functionality into a separate hypercall handler file. Signed-off-by: Christoffer Dall <christoffer.dall@arm.com> [steven.price@arm.com: rebased] Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Steven Price <steven.price@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-07-05KVM: arm/arm64: Add save/restore support for firmware workaround stateAndre Przywara1-15/+124
KVM implements the firmware interface for mitigating cache speculation vulnerabilities. Guests may use this interface to ensure mitigation is active. If we want to migrate such a guest to a host with a different support level for those workarounds, migration might need to fail, to ensure that critical guests don't loose their protection. Introduce a way for userland to save and restore the workarounds state. On restoring we do checks that make sure we don't downgrade our mitigation level. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Steven Price <steven.price@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-07-05arm64: KVM: Propagate full Spectre v2 workaround state to KVM guestsAndre Przywara1-1/+9
Recent commits added the explicit notion of "workaround not required" to the state of the Spectre v2 (aka. BP_HARDENING) workaround, where we just had "needed" and "unknown" before. Export this knowledge to the rest of the kernel and enhance the existing kvm_arm_harden_branch_predictor() to report this new state as well. Export this new state to guests when they use KVM's firmware interface emulation. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Steven Price <steven.price@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234Thomas Gleixner1-12/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 503 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Enrico Weigelt <info@metux.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-07arm/arm64: KVM: Allow a VCPU to fully reset itselfMarc Zyngier1-20/+16
The current kvm_psci_vcpu_on implementation will directly try to manipulate the state of the VCPU to reset it. However, since this is not done on the thread that runs the VCPU, we can end up in a strangely corrupted state when the source and target VCPUs are running at the same time. Fix this by factoring out all reset logic from the PSCI implementation and forwarding the required information along with a request to the target VCPU. Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
2018-06-20sched/swait: Rename to exclusivePeter Zijlstra1-1/+1
Since swait basically implemented exclusive waits only, make sure the API reflects that. $ git grep -l -e "\<swake_up\>" -e "\<swait_event[^ (]*" -e "\<prepare_to_swait\>" | while read file; do sed -i -e 's/\<swake_up\>/&_one/g' -e 's/\<swait_event[^ (]*/&_exclusive/g' -e 's/\<prepare_to_swait\>/&_exclusive/g' $file; done With a few manual touch-ups. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: bigeasy@linutronix.de Cc: oleg@redhat.com Cc: paulmck@linux.vnet.ibm.com Cc: pbonzini@redhat.com Link: https://lkml.kernel.org/r/20180612083909.261946548@infradead.org
2018-05-31arm64: KVM: Add ARCH_WORKAROUND_2 discovery through ARCH_FEATURES_FUNC_IDMarc Zyngier1-2/+16
Now that all our infrastructure is in place, let's expose the availability of ARCH_WORKAROUND_2 to guests. We take this opportunity to tidy up a couple of SMCCC constants. Acked-by: Christoffer Dall <christoffer.dall@arm.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-04-20arm/arm64: KVM: Add PSCI version selection APIMarc Zyngier1-0/+60
Although we've implemented PSCI 0.1, 0.2 and 1.0, we expose either 0.1 or 1.0 to a guest, defaulting to the latest version of the PSCI implementation that is compatible with the requested version. This is no different from doing a firmware upgrade on KVM. But in order to give a chance to hypothetical badly implemented guests that would have a fit by discovering something other than PSCI 0.2, let's provide a new API that allows userspace to pick one particular version of the API. This is implemented as a new class of "firmware" registers, where we expose the PSCI version. This allows the PSCI version to be save/restored as part of a guest migration, and also set to any supported version if the guest requires it. Cc: stable@vger.kernel.org #4.16 Reviewed-by: Christoffer Dall <cdall@kernel.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-02-06arm64: KVM: Report SMCCC_ARCH_WORKAROUND_1 BP hardening supportMarc Zyngier1-1/+8
A new feature of SMCCC 1.1 is that it offers firmware-based CPU workarounds. In particular, SMCCC_ARCH_WORKAROUND_1 provides BP hardening for CVE-2017-5715. If the host has some mitigation for this issue, report that we deal with it using SMCCC_ARCH_WORKAROUND_1, as we apply the host workaround on every guest exit. Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06arm/arm64: KVM: Turn kvm_psci_version into a static inlineMarc Zyngier1-10/+2
We're about to need kvm_psci_version in HYP too. So let's turn it into a static inline, and pass the kvm structure as a second parameter (so that HYP can do a kern_hyp_va on it). Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06arm/arm64: KVM: Advertise SMCCC v1.1Marc Zyngier1-1/+23
The new SMC Calling Convention (v1.1) allows for a reduced overhead when calling into the firmware, and provides a new feature discovery mechanism. Make it visible to KVM guests. Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06arm/arm64: KVM: Implement PSCI 1.0 supportMarc Zyngier1-1/+44
PSCI 1.0 can be trivially implemented by providing the FEATURES call on top of PSCI 0.2 and returning 1.0 as the PSCI version. We happily ignore everything else, as they are either optional or are clarifications that do not require any additional change. PSCI 1.0 is now the default until we decide to add a userspace selection API. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06arm/arm64: KVM: Add smccc accessors to PSCI codeMarc Zyngier1-10/+42
Instead of open coding the accesses to the various registers, let's add explicit SMCCC accessors. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06arm/arm64: KVM: Add PSCI_VERSION helperMarc Zyngier1-3/+1
As we're about to trigger a PSCI version explosion, it doesn't hurt to introduce a PSCI_VERSION helper that is going to be used everywhere. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06arm/arm64: KVM: Consolidate the PSCI include filesMarc Zyngier1-1/+2
As we're about to update the PSCI support, and because I'm lazy, let's move the PSCI include file to include/kvm so that both ARM architectures can find it. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-06-04KVM: arm/arm64: change exit request to sleep requestAndrew Jones1-2/+2
A request called EXIT is too generic. All requests are meant to cause exits, but different requests have different flags. Let's not make it difficult to decide if the EXIT request is correct for some case by just always providing unique requests for each case. This patch changes EXIT to SLEEP, because that's what the request is asking the VCPU to do. Signed-off-by: Andrew Jones <drjones@redhat.com> Acked-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-06-04KVM: arm/arm64: optimize VCPU RUNAndrew Jones1-0/+2
We can make a small optimization by not checking the state of the power_off field on each run. This is done by treating power_off like pause, only checking it when we get the EXIT VCPU request. When a VCPU powers off another VCPU the EXIT request is already made, so we just need to make sure the request is also made on self power off. kvm_vcpu_kick() isn't necessary for these cases, as the VCPU would just be kicking itself, but we add it anyway as a self kick doesn't cost much, and it makes the code more future-proof. Signed-off-by: Andrew Jones <drjones@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-06-04KVM: arm/arm64: use vcpu requests for power_offAndrew Jones1-3/+2
System shutdown is currently using request-less VCPU kicks. This leaves open a tiny race window, as it doesn't ensure the state change to power_off is seen by a VCPU just about to enter guest mode. VCPU requests, OTOH, are guaranteed to be seen (see "Ensuring Requests Are Seen" of Documentation/virtual/kvm/vcpu-requests.rst) This patch applies the EXIT request used by pause to power_off, fixing the race. Signed-off-by: Andrew Jones <drjones@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-06-04KVM: arm/arm64: properly use vcpu requestsAndrew Jones1-0/+1
arm/arm64 already has one VCPU request used when setting pause, but it doesn't properly check requests in VCPU RUN. Check it and also make sure we set vcpu->mode at the appropriate time (before the check) and with the appropriate barriers. See Documentation/virtual/kvm/vcpu-requests.rst. Also make sure we don't leave any vcpu requests we don't intend to handle later set in the request bitmap. If we don't clear them, then kvm_request_pending() may return true when it shouldn't. Using VCPU requests properly fixes a small race where pause could get set just as a VCPU was entering guest mode. Signed-off-by: Andrew Jones <drjones@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-05-04KVM: arm/arm64: Move shared files to virt/kvm/armChristoffer Dall1-0/+332
For some time now we have been having a lot of shared functionality between the arm and arm64 KVM support in arch/arm, which not only required a horrible inter-arch reference from the Makefile in arch/arm64/kvm, but also created confusion for newcomers to the code base, as was recently seen on the mailing list. Further, it causes confusion for things like cscope, which needs special attention to index specific shared files for arm64 from the arm tree. Move the shared files into virt/kvm/arm and move the trace points along with it. When moving the tracepoints we have to modify the way the vgic creates definitions of the trace points, so we take the chance to include the VGIC tracepoints in its very own special vgic trace.h file. Signed-off-by: Christoffer Dall <cdall@linaro.org>