From e329fb75d519e3dc3eb11b22d5bb846516be3521 Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Tue, 11 Dec 2018 15:26:31 +0100 Subject: KVM: arm/arm64: Factor out VMID into struct kvm_vmid 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 [maz: minor cleanups] Reviewed-by: Julien Thierry Signed-off-by: Christoffer Dall Signed-off-by: Marc Zyngier --- virt/kvm/arm/mmu.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'virt/kvm/arm/mmu.c') diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c index fbdf3ac2f001..f8dda452ea24 100644 --- a/virt/kvm/arm/mmu.c +++ b/virt/kvm/arm/mmu.c @@ -908,6 +908,7 @@ int create_hyp_exec_mappings(phys_addr_t phys_addr, size_t size, */ int kvm_alloc_stage2_pgd(struct kvm *kvm) { + phys_addr_t pgd_phys; pgd_t *pgd; if (kvm->arch.pgd != NULL) { @@ -920,7 +921,12 @@ int kvm_alloc_stage2_pgd(struct kvm *kvm) if (!pgd) return -ENOMEM; + pgd_phys = virt_to_phys(pgd); + if (WARN_ON(pgd_phys & ~kvm_vttbr_baddr_mask(kvm))) + return -EINVAL; + kvm->arch.pgd = pgd; + kvm->arch.pgd_phys = pgd_phys; return 0; } @@ -1008,6 +1014,7 @@ void kvm_free_stage2_pgd(struct kvm *kvm) unmap_stage2_range(kvm, 0, kvm_phys_size(kvm)); pgd = READ_ONCE(kvm->arch.pgd); kvm->arch.pgd = NULL; + kvm->arch.pgd_phys = 0; } spin_unlock(&kvm->mmu_lock); -- cgit From 64cf98fa5544aee6c547786ee32f92b796b30635 Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Sun, 1 May 2016 22:29:58 +0200 Subject: KVM: arm/arm64: Move kvm_is_write_fault to header file Move this little function to the header files for arm/arm64 so other code can make use of it directly. Signed-off-by: Christoffer Dall Signed-off-by: Marc Zyngier --- virt/kvm/arm/mmu.c | 8 -------- 1 file changed, 8 deletions(-) (limited to 'virt/kvm/arm/mmu.c') diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c index f8dda452ea24..e3e5a26b4845 100644 --- a/virt/kvm/arm/mmu.c +++ b/virt/kvm/arm/mmu.c @@ -1403,14 +1403,6 @@ static bool transparent_hugepage_adjust(kvm_pfn_t *pfnp, phys_addr_t *ipap) return false; } -static bool kvm_is_write_fault(struct kvm_vcpu *vcpu) -{ - if (kvm_vcpu_trap_is_iabt(vcpu)) - return false; - - return kvm_vcpu_dabt_iswrite(vcpu); -} - /** * stage2_wp_ptes - write protect PMD range * @pmd: pointer to pmd entry -- cgit From c2be79a0bcf34ed975787e03a129936df17ec0dc Mon Sep 17 00:00:00 2001 From: Shaokun Zhang Date: Tue, 19 Feb 2019 17:22:21 +0800 Subject: KVM: arm/arm64: Remove unused gpa_end variable The 'gpa_end' local variable is never used and let's remove it. Cc: Christoffer Dall Signed-off-by: Shaokun Zhang Signed-off-by: Marc Zyngier --- virt/kvm/arm/mmu.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'virt/kvm/arm/mmu.c') diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c index e3e5a26b4845..aae68da2717f 100644 --- a/virt/kvm/arm/mmu.c +++ b/virt/kvm/arm/mmu.c @@ -1597,14 +1597,13 @@ static void kvm_send_hwpoison_signal(unsigned long address, static bool fault_supports_stage2_pmd_mappings(struct kvm_memory_slot *memslot, unsigned long hva) { - gpa_t gpa_start, gpa_end; + gpa_t gpa_start; hva_t uaddr_start, uaddr_end; size_t size; size = memslot->npages * PAGE_SIZE; gpa_start = memslot->base_gfn << PAGE_SHIFT; - gpa_end = gpa_start + size; uaddr_start = memslot->userspace_addr; uaddr_end = uaddr_start + size; -- cgit From 152482580a1b0accb60676063a1ac57b2d12daf6 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Tue, 5 Feb 2019 12:54:17 -0800 Subject: KVM: Call kvm_arch_memslots_updated() before updating memslots kvm_arch_memslots_updated() is at this point in time an x86-specific hook for handling MMIO generation wraparound. x86 stashes 19 bits of the memslots generation number in its MMIO sptes in order to avoid full page fault walks for repeat faults on emulated MMIO addresses. Because only 19 bits are used, wrapping the MMIO generation number is possible, if unlikely. kvm_arch_memslots_updated() alerts x86 that the generation has changed so that it can invalidate all MMIO sptes in case the effective MMIO generation has wrapped so as to avoid using a stale spte, e.g. a (very) old spte that was created with generation==0. Given that the purpose of kvm_arch_memslots_updated() is to prevent consuming stale entries, it needs to be called before the new generation is propagated to memslots. Invalidating the MMIO sptes after updating memslots means that there is a window where a vCPU could dereference the new memslots generation, e.g. 0, and incorrectly reuse an old MMIO spte that was created with (pre-wrap) generation==0. Fixes: e59dbe09f8e6 ("KVM: Introduce kvm_arch_memslots_updated()") Cc: Signed-off-by: Sean Christopherson Signed-off-by: Paolo Bonzini --- virt/kvm/arm/mmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'virt/kvm/arm/mmu.c') diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c index fbdf3ac2f001..e0355e0f8712 100644 --- a/virt/kvm/arm/mmu.c +++ b/virt/kvm/arm/mmu.c @@ -2350,7 +2350,7 @@ int kvm_arch_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot, return 0; } -void kvm_arch_memslots_updated(struct kvm *kvm, struct kvm_memslots *slots) +void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) { } -- cgit