From fb67e14fc90f18250259faf61a269320ea8e4d8f Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Tue, 7 Dec 2010 10:35:25 +0800 Subject: [PATCH] KVM: MMU: retry #PF for softmmu Retry #PF for softmmu only when the current vcpu has the same cr3 as the time when #PF occurs Signed-off-by: Xiao Guangrong Signed-off-by: Avi Kivity --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/mmu.c | 2 ++ arch/x86/kvm/paging_tmpl.h | 14 +++++++++----- arch/x86/kvm/x86.c | 6 +++++- 4 files changed, 17 insertions(+), 6 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index aa1518d794cc..4461429957a9 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -593,6 +593,7 @@ struct kvm_x86_ops { struct kvm_arch_async_pf { u32 token; gfn_t gfn; + unsigned long cr3; bool direct_map; }; diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index d475b6b87dce..abda57fac659 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -2608,9 +2608,11 @@ static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gva_t gva, static int kvm_arch_setup_async_pf(struct kvm_vcpu *vcpu, gva_t gva, gfn_t gfn) { struct kvm_arch_async_pf arch; + arch.token = (vcpu->arch.apf.id++ << 12) | vcpu->vcpu_id; arch.gfn = gfn; arch.direct_map = vcpu->arch.mmu.direct_map; + arch.cr3 = vcpu->arch.mmu.get_cr3(vcpu); return kvm_setup_async_pf(vcpu, gva, gfn, &arch); } diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index 52b3e91918c6..146b681e6ab0 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -438,7 +438,8 @@ static void FNAME(pte_prefetch)(struct kvm_vcpu *vcpu, struct guest_walker *gw, static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr, struct guest_walker *gw, int user_fault, int write_fault, int hlevel, - int *ptwrite, pfn_t pfn, bool map_writable) + int *ptwrite, pfn_t pfn, bool map_writable, + bool prefault) { unsigned access = gw->pt_access; struct kvm_mmu_page *sp = NULL; @@ -512,7 +513,7 @@ static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr, mmu_set_spte(vcpu, it.sptep, access, gw->pte_access & access, user_fault, write_fault, dirty, ptwrite, it.level, - gw->gfn, pfn, false, map_writable); + gw->gfn, pfn, prefault, map_writable); FNAME(pte_prefetch)(vcpu, gw, it.sptep); return it.sptep; @@ -568,8 +569,11 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code, */ if (!r) { pgprintk("%s: guest page fault\n", __func__); - inject_page_fault(vcpu, &walker.fault); - vcpu->arch.last_pt_write_count = 0; /* reset fork detector */ + if (!prefault) { + inject_page_fault(vcpu, &walker.fault); + /* reset fork detector */ + vcpu->arch.last_pt_write_count = 0; + } return 0; } @@ -599,7 +603,7 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code, trace_kvm_mmu_audit(vcpu, AUDIT_PRE_PAGE_FAULT); kvm_mmu_free_some_pages(vcpu); sptep = FNAME(fetch)(vcpu, addr, &walker, user_fault, write_fault, - level, &write_pt, pfn, map_writable); + level, &write_pt, pfn, map_writable, prefault); (void)sptep; pgprintk("%s: shadow pte %p %llx ptwrite %d\n", __func__, sptep, *sptep, write_pt); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 8b4d5fc08012..cd71d210c409 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6182,7 +6182,7 @@ void kvm_arch_async_page_ready(struct kvm_vcpu *vcpu, struct kvm_async_pf *work) { int r; - if (!vcpu->arch.mmu.direct_map || !work->arch.direct_map || + if ((vcpu->arch.mmu.direct_map != work->arch.direct_map) || is_error_page(work->page)) return; @@ -6190,6 +6190,10 @@ void kvm_arch_async_page_ready(struct kvm_vcpu *vcpu, struct kvm_async_pf *work) if (unlikely(r)) return; + if (!vcpu->arch.mmu.direct_map && + work->arch.cr3 != vcpu->arch.mmu.get_cr3(vcpu)) + return; + vcpu->arch.mmu.page_fault(vcpu, work->gva, 0, true); }