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2020-03-24arm: Remove 32bit KVM host supportMarc Zyngier1-242/+0
That's it. Remove all references to KVM itself, and document that although it is no more, the ABI between SVC and HYP still exists. Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Will Deacon <will@kernel.org> Acked-by: Vladimir Murzin <vladimir.murzin@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Christoffer Dall <christoffer.dall@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>
2019-02-19KVM: arm/arm64: Factor out VMID into struct kvm_vmidChristoffer Dall1-1/+1
In preparation for nested virtualization where we are going to have more than a single VMID per VM, let's factor out the VMID data into a separate VMID data structure and change the VMID allocator to operate on this new structure instead of using a struct kvm. This also means that udate_vttbr now becomes update_vmid, and that the vttbr itself is generated on the fly based on the stage 2 page table base address and the vmid. We cache the physical address of the pgd when allocating the pgd to avoid doing the calculation on every entry to the guest and to avoid calling into potentially non-hyp-mapped code from hyp/EL2. If we wanted to merge the VMID allocator with the arm64 ASID allocator at some point in the future, it should actually become easier to do that after this patch. Note that to avoid mapping the kvm_vmid_bits variable into hyp, we simply forego the masking of the vmid value in kvm_get_vttbr and rely on update_vmid to always assign a valid vmid value (within the supported range). Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> [maz: minor cleanups] Reviewed-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Avoid VGICv3 save/restore on VHE with no IRQsChristoffer Dall1-2/+6
We can finally get completely rid of any calls to the VGICv3 save/restore functions when the AP lists are empty on VHE systems. This requires carefully factoring out trap configuration from saving and restoring state, and carefully choosing what to do on the VHE and non-VHE path. One of the challenges is that we cannot save/restore the VMCR lazily because we can only write the VMCR when ICC_SRE_EL1.SRE is cleared when emulating a GICv2-on-GICv3, since otherwise all Group-0 interrupts end up being delivered as FIQ. To solve this problem, and still provide fast performance in the fast path of exiting a VM when no interrupts are pending (which also optimized the latency for actually delivering virtual interrupts coming from physical interrupts), we orchestrate a dance of only doing the activate/deactivate traps in vgic load/put for VHE systems (which can have ICC_SRE_EL1.SRE cleared when running in the host), and doing the configuration on every round-trip on non-VHE systems. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Handle VGICv2 save/restore from the main VGIC codeChristoffer Dall1-4/+0
We can program the GICv2 hypervisor control interface logic directly from the core vgic code and can instead do the save/restore directly from the flush/sync functions, which can lead to a number of future optimizations. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm64: Introduce VHE-specific kvm_vcpu_runChristoffer Dall1-1/+1
So far this is mostly (see below) a copy of the legacy non-VHE switch function, but we will start reworking these functions in separate directions to work on VHE and non-VHE in the most optimal way in later patches. The only difference after this patch between the VHE and non-VHE run functions is that we omit the branch-predictor variant-2 hardening for QC Falkor CPUs, because this workaround is specific to a series of non-VHE ARMv8.0 CPUs. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19KVM: arm/arm64: Get rid of vcpu->arch.irq_linesChristoffer Dall1-1/+1
We currently have a separate read-modify-write of the HCR_EL2 on entry to the guest for the sole purpose of setting the VF and VI bits, if set. Since this is most rarely the case (only when using userspace IRQ chip and interrupts are in flight), let's get rid of this operation and instead modify the bits in the vcpu->arch.hcr[_el2] directly when needed. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-01-08KVM: arm/arm64: Detangle kvm_mmu.h from kvm_hyp.hMarc Zyngier1-0/+1
kvm_hyp.h has an odd dependency on kvm_mmu.h, which makes the opposite inclusion impossible. Let's start with breaking that useless dependency. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-11-06KVM: arm/arm64: Move timer save/restore out of the hyp codeChristoffer Dall1-3/+4
As we are about to be lazy with saving and restoring the timer registers, we prepare by moving all possible timer configuration logic out of the hyp code. All virtual timer registers can be programmed from EL1 and since the arch timer is always a level triggered interrupt we can safely do this with interrupts disabled in the host kernel on the way to the guest without taking vtimer interrupts in the host kernel (yet). The downside is that the cntvoff register can only be programmed from hyp mode, so we jump into hyp mode and back to program it. This is also safe, because the host kernel doesn't use the virtual timer in the KVM code. It may add a little performance performance penalty, but only until following commits where we move this operation to vcpu load/put. Signed-off-by: Christoffer Dall <cdall@linaro.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
2017-06-15Merge branch 'kvmarm-master/master' into HEADMarc Zyngier1-1/+3
2017-05-16KVM: arm: Restore banked registers and physical timer access on hyp_panic()James Morse1-0/+2
When KVM panics, it hurridly restores the host context and parachutes into the host's panic() code. This looks like it was copied from arm64, the 32bit KVM panic code needs to restore the host's banked registers too. At some point panic() touches the physical timer/counter, this will trap back to HYP. If we're lucky, we panic again. Add a __timer_save_state() call to KVMs hyp_panic() path, this saves the guest registers and disables the traps for the host. Fixes: c36b6db5f3e4 ("ARM: KVM: Add panic handling code") Signed-off-by: James Morse <james.morse@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-05-15KVM: arm: plug potential guest hardware debug leakageZhichao Huang1-1/+3
Hardware debugging in guests is not intercepted currently, it means that a malicious guest can bring down the entire machine by writing to the debug registers. This patch enable trapping of all debug registers, preventing the guests to access the debug registers. This includes access to the debug mode(DBGDSCR) in the guest world all the time which could otherwise mess with the host state. Reads return 0 and writes are ignored (RAZ_WI). The result is the guest cannot detect any working hardware based debug support. As debug exceptions are still routed to the guest normal debug using software based breakpoints still works. To support debugging using hardware registers we need to implement a debug register aware world switch as well as special trapping for registers that may affect the host state. Cc: stable@vger.kernel.org Signed-off-by: Zhichao Huang <zhichao.huang@linaro.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
2016-09-22ARM: KVM: Support vgic-v3Vladimir Murzin1-2/+10
This patch allows to build and use vgic-v3 in 32-bit mode. Unfortunately, it can not be split in several steps without extra stubs to keep patches independent and bisectable. For instance, virt/kvm/arm/vgic/vgic-v3.c uses function from vgic-v3-sr.c, handling access to GICv3 cpu interface from the guest requires vgic_v3.vgic_sre to be already defined. It is how support has been done: * handle SGI requests from the guest * report configured SRE on access to GICv3 cpu interface from the guest * required vgic-v3 macros are provided via uapi.h * static keys are used to select GIC backend * to make vgic-v3 build KVM_ARM_VGIC_V3 guard is removed along with the static inlines Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08arm: KVM: Preserve pending Virtual Abort in world switchMarc Zyngier1-0/+9
The HCR.VA bit is used to signal an Abort to a guest, and has the peculiar feature of getting cleared when the guest has taken the abort (this is the only bit that behaves as such in this register). This means that if we signal such an abort, we must leave it in the guest context until it disappears from HCR, and at which point it must be cleared from the context. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-09-08KVM: arm/arm64: Get rid of exported aliases to static functionsChristoffer Dall1-3/+1
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>
2016-02-29ARM: KVM: Move kvm/hyp/hyp.h to include/asm/kvm_hyp.hMarc Zyngier1-1/+1
In order to be able to use the code located in virt/kvm/arm/hyp, we need to make the global hyp.h file accessible from include/asm, similar to what we did for arm64. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29ARM: KVM: Remove __weak attributesMarc Zyngier1-1/+1
Now that the old code is long gone, we can remove all the weak attributes, as there is only one version of the code. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29ARM: KVM: Add panic handling codeMarc Zyngier1-0/+38
Instead of spinning forever, let's "properly" handle any unexpected exception ("properly" meaning "print a spat on the console and die"). This has proved useful quite a few times... Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29ARM: KVM: Add populating of fault data structureMarc Zyngier1-0/+54
On guest exit, we must take care of populating our fault data structure so that the host code can handle it. This includes resolving the IPA for permission faults, which can result in restarting the guest. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-02-29ARM: KVM: Add the new world switch implementationMarc Zyngier1-0/+140
The new world switch implementation is modeled after the arm64 one, calling the various save/restore functions in turn, and having as little state as possible. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>