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| author |   Wanpeng Li <wanpeng.li@hotmail.com> | 2017-08-10 16:28:02 -0700 |
|---|---|---|
| committer |   Paolo Bonzini <pbonzini@redhat.com> | 2017-08-11 18:59:29 +0200 |
| commit | 26eeb53cf0f9a0557be09b7efdeb2392c92b1a4f (patch) | |
| tree | e4f326dfe0dd87a7145be75bce8c8e1de38eae2f /arch/x86/kvm/mmu.c | |
| parent | KVM: MMU: Fix softlockup due to mmu_lock is held too long (diff) | |
| download | linux-dev-26eeb53cf0f9a0557be09b7efdeb2392c92b1a4f.tar.xz linux-dev-26eeb53cf0f9a0557be09b7efdeb2392c92b1a4f.zip | |
KVM: MMU: Bail out immediately if there is no available mmu page
Bailing out immediately if there is no available mmu page to alloc.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/mmu.c')
| -rw-r--r-- | arch/x86/kvm/mmu.c | 36 |
1 files changed, 27 insertions, 9 deletions
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index e4ce20bee5de..e721e10afda1 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -3257,7 +3257,7 @@ static bool fast_page_fault(struct kvm_vcpu *vcpu, gva_t gva, int level, static bool try_async_pf(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn, gva_t gva, kvm_pfn_t *pfn, bool write, bool *writable); -static void make_mmu_pages_available(struct kvm_vcpu *vcpu); +static int make_mmu_pages_available(struct kvm_vcpu *vcpu); static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, u32 error_code, gfn_t gfn, bool prefault) @@ -3297,7 +3297,8 @@ static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, u32 error_code, spin_lock(&vcpu->kvm->mmu_lock); if (mmu_notifier_retry(vcpu->kvm, mmu_seq)) goto out_unlock; - make_mmu_pages_available(vcpu); + if (make_mmu_pages_available(vcpu) < 0) + goto out_unlock; if (likely(!force_pt_level)) transparent_hugepage_adjust(vcpu, &gfn, &pfn, &level); r = __direct_map(vcpu, write, map_writable, level, gfn, pfn, prefault); @@ -3376,7 +3377,10 @@ static int mmu_alloc_direct_roots(struct kvm_vcpu *vcpu) if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) { spin_lock(&vcpu->kvm->mmu_lock); - make_mmu_pages_available(vcpu); + if(make_mmu_pages_available(vcpu) < 0) { + spin_unlock(&vcpu->kvm->mmu_lock); + return 1; + } sp = kvm_mmu_get_page(vcpu, 0, 0, PT64_ROOT_LEVEL, 1, ACC_ALL); ++sp->root_count; spin_unlock(&vcpu->kvm->mmu_lock); @@ -3387,7 +3391,10 @@ static int mmu_alloc_direct_roots(struct kvm_vcpu *vcpu) MMU_WARN_ON(VALID_PAGE(root)); spin_lock(&vcpu->kvm->mmu_lock); - make_mmu_pages_available(vcpu); + if (make_mmu_pages_available(vcpu) < 0) { + spin_unlock(&vcpu->kvm->mmu_lock); + return 1; + } sp = kvm_mmu_get_page(vcpu, i << (30 - PAGE_SHIFT), i << 30, PT32_ROOT_LEVEL, 1, ACC_ALL); root = __pa(sp->spt); @@ -3424,7 +3431,10 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu) MMU_WARN_ON(VALID_PAGE(root)); spin_lock(&vcpu->kvm->mmu_lock); - make_mmu_pages_available(vcpu); + if (make_mmu_pages_available(vcpu) < 0) { + spin_unlock(&vcpu->kvm->mmu_lock); + return 1; + } sp = kvm_mmu_get_page(vcpu, root_gfn, 0, PT64_ROOT_LEVEL, 0, ACC_ALL); root = __pa(sp->spt); @@ -3458,7 +3468,10 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu) return 1; } spin_lock(&vcpu->kvm->mmu_lock); - make_mmu_pages_available(vcpu); + if (make_mmu_pages_available(vcpu) < 0) { + spin_unlock(&vcpu->kvm->mmu_lock); + return 1; + } sp = kvm_mmu_get_page(vcpu, root_gfn, i << 30, PT32_ROOT_LEVEL, 0, ACC_ALL); root = __pa(sp->spt); @@ -3867,7 +3880,8 @@ static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa, u32 error_code, spin_lock(&vcpu->kvm->mmu_lock); if (mmu_notifier_retry(vcpu->kvm, mmu_seq)) goto out_unlock; - make_mmu_pages_available(vcpu); + if (make_mmu_pages_available(vcpu) < 0) + goto out_unlock; if (likely(!force_pt_level)) transparent_hugepage_adjust(vcpu, &gfn, &pfn, &level); r = __direct_map(vcpu, write, map_writable, level, gfn, pfn, prefault); @@ -4786,12 +4800,12 @@ int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva) } EXPORT_SYMBOL_GPL(kvm_mmu_unprotect_page_virt); -static void make_mmu_pages_available(struct kvm_vcpu *vcpu) +static int make_mmu_pages_available(struct kvm_vcpu *vcpu) { LIST_HEAD(invalid_list); if (likely(kvm_mmu_available_pages(vcpu->kvm) >= KVM_MIN_FREE_MMU_PAGES)) - return; + return 0; while (kvm_mmu_available_pages(vcpu->kvm) < KVM_REFILL_PAGES) { if (!prepare_zap_oldest_mmu_page(vcpu->kvm, &invalid_list)) @@ -4800,6 +4814,10 @@ static void make_mmu_pages_available(struct kvm_vcpu *vcpu) ++vcpu->kvm->stat.mmu_recycled; } kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list); + + if (!kvm_mmu_available_pages(vcpu->kvm)) + return -ENOSPC; + return 0; } int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t cr2, u64 error_code, |