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path: root/arch/arm64/kvm/hyp/tlb.c
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2017-03-20arm64: KVM: Add support for VPIPT I-cachesWill Deacon
A VPIPT I-cache has two main properties: 1. Lines allocated into the cache are tagged by VMID and a lookup can only hit lines that were allocated with the current VMID. 2. I-cache invalidation from EL1/0 only invalidates lines that match the current VMID of the CPU doing the invalidation. This can cause issues with non-VHE configurations, where the host runs at EL1 and wants to invalidate I-cache entries for a guest running with a different VMID. VHE is not affected, because the host runs at EL2 and I-cache invalidation applies as expected. This patch solves the problem by invalidating the I-cache when unmapping a page at stage 2 on a system with a VPIPT I-cache but not running with VHE enabled. Hopefully this is an obscure enough configuration that the overhead isn't anything to worry about, although it does mean that the by-range I-cache invalidation currently performed when mapping at stage 2 can be elided on such systems, because the I-cache will be clean for the guest VMID following a rollover event. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-06arm64: KVM: VHE: Clear HCR_TGE when invalidating guest TLBsMarc Zyngier
When invalidating guest TLBs, special care must be taken to actually shoot the guest TLBs and not the host ones if we're running on a VHE system. This is controlled by the HCR_EL2.TGE bit, which we forget to clear before invalidating TLBs. Address the issue by introducing two wrappers (__tlb_switch_to_guest and __tlb_switch_to_host) that take care of both the VTTBR_EL2 and HCR_EL2.TGE switching. Reported-by: Tomasz Nowicki <tnowicki@caviumnetworks.com> Tested-by: Tomasz Nowicki <tnowicki@caviumnetworks.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Cc: stable@vger.kernel.org Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-01-27arm64: Use __tlbi() macros in KVM codeChristopher Covington
Refactor the KVM code to use the __tlbi macros, which will allow an errata workaround that repeats tlbi dsb sequences to only change one location. This is not intended to change the generated assembly and comparing before and after vmlinux objdump shows no functional changes. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Christopher Covington <cov@codeaurora.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-11-04arm/arm64: KVM: Perform local TLB invalidation when multiplexing vcpus on a ↵Marc Zyngier
single CPU Architecturally, TLBs are private to the (physical) CPU they're associated with. But when multiple vcpus from the same VM are being multiplexed on the same CPU, the TLBs are not private to the vcpus (and are actually shared across the VMID). Let's consider the following scenario: - vcpu-0 maps PA to VA - vcpu-1 maps PA' to VA If run on the same physical CPU, vcpu-1 can hit TLB entries generated by vcpu-0 accesses, and access the wrong physical page. The solution to this is to keep a per-VM map of which vcpu ran last on each given physical CPU, and invalidate local TLBs when switching to a different vcpu from the same VM. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-09-08KVM: arm/arm64: Get rid of exported aliases to static functionsChristoffer Dall
When rewriting the assembly code to C code, it was useful to have exported aliases or static functions so that we could keep the existing common C code unmodified and at the same time rewrite arm64 from assembly to C code, and later do the arm part. Now when both are done, we really don't need this level of indirection anymore, and it's time to save a few lines and brain cells. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-02-29arm64: KVM: Move kvm/hyp/hyp.h to include/asm/kvm_hyp.hMarc Zyngier
In order to be able to move code outside of kvm/hyp, we need to make the global hyp.h file accessible from a standard location. include/asm/kvm_hyp.h seems good enough. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-12-14arm64: KVM: Remove weak attributesMarc Zyngier
As we've now switched to the new world switch implementation, remove the weak attributes, as nobody is supposed to override it anymore. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-12-14arm64: KVM: Add compatibility aliasesMarc Zyngier
So far, we've implemented the new world switch with a completely different namespace, so that we could have both implementation compiled in. Let's take things one step further by adding weak aliases that have the same names as the original implementation. The weak attributes allows the new implementation to be overriden by the old one, and everything still work. At a later point, we'll be able to simply drop the old code, and everything will hopefully keep working, thanks to the aliases we have just added. This also saves us repainting all the callers. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-12-14arm64: KVM: Implement TLB handlingMarc Zyngier
Implement the TLB handling as a direct translation of the assembly code version. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>