| Message ID | 20240726235234.228822-57-seanjc@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: Stop grabbing references to PFNMAP'd pages | expand |
On Fri, Jul 26, 2024 at 04:52:05PM GMT, Sean Christopherson wrote: > Don't mark pages dirty if KVM bails from the page fault handler without > installing a stage-2 mapping, i.e. if the page is guaranteed to not be > written by the guest. > > In addition to being a (very) minor fix, this paves the way for converting > RISC-V to use kvm_release_faultin_page(). > > Signed-off-by: Sean Christopherson <seanjc@google.com> > --- > arch/riscv/kvm/mmu.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c > index b63650f9b966..06aa5a0d056d 100644 > --- a/arch/riscv/kvm/mmu.c > +++ b/arch/riscv/kvm/mmu.c > @@ -669,7 +669,6 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu, > goto out_unlock; > > if (writable) { > - kvm_set_pfn_dirty(hfn); > mark_page_dirty(kvm, gfn); > ret = gstage_map_page(kvm, pcache, gpa, hfn << PAGE_SHIFT, > vma_pagesize, false, true); > @@ -682,6 +681,9 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu, > kvm_err("Failed to map in G-stage\n"); > > out_unlock: > + if ((!ret || ret == -EEXIST) && writable) > + kvm_set_pfn_dirty(hfn); > + > spin_unlock(&kvm->mmu_lock); > kvm_set_pfn_accessed(hfn); > kvm_release_pfn_clean(hfn); > -- > 2.46.0.rc1.232.g9752f9e123-goog > Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
On Sat, Jul 27, 2024 at 5:24 AM Sean Christopherson <seanjc@google.com> wrote: > > Don't mark pages dirty if KVM bails from the page fault handler without > installing a stage-2 mapping, i.e. if the page is guaranteed to not be > written by the guest. > > In addition to being a (very) minor fix, this paves the way for converting > RISC-V to use kvm_release_faultin_page(). > > Signed-off-by: Sean Christopherson <seanjc@google.com> For KVM RISC-V: Acked-by: Anup Patel <anup@brainfault.org> Regards, Anup > --- > arch/riscv/kvm/mmu.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c > index b63650f9b966..06aa5a0d056d 100644 > --- a/arch/riscv/kvm/mmu.c > +++ b/arch/riscv/kvm/mmu.c > @@ -669,7 +669,6 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu, > goto out_unlock; > > if (writable) { > - kvm_set_pfn_dirty(hfn); > mark_page_dirty(kvm, gfn); > ret = gstage_map_page(kvm, pcache, gpa, hfn << PAGE_SHIFT, > vma_pagesize, false, true); > @@ -682,6 +681,9 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu, > kvm_err("Failed to map in G-stage\n"); > > out_unlock: > + if ((!ret || ret == -EEXIST) && writable) > + kvm_set_pfn_dirty(hfn); > + > spin_unlock(&kvm->mmu_lock); > kvm_set_pfn_accessed(hfn); > kvm_release_pfn_clean(hfn); > -- > 2.46.0.rc1.232.g9752f9e123-goog >
diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c index b63650f9b966..06aa5a0d056d 100644 --- a/arch/riscv/kvm/mmu.c +++ b/arch/riscv/kvm/mmu.c @@ -669,7 +669,6 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu, goto out_unlock; if (writable) { - kvm_set_pfn_dirty(hfn); mark_page_dirty(kvm, gfn); ret = gstage_map_page(kvm, pcache, gpa, hfn << PAGE_SHIFT, vma_pagesize, false, true); @@ -682,6 +681,9 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu, kvm_err("Failed to map in G-stage\n"); out_unlock: + if ((!ret || ret == -EEXIST) && writable) + kvm_set_pfn_dirty(hfn); + spin_unlock(&kvm->mmu_lock); kvm_set_pfn_accessed(hfn); kvm_release_pfn_clean(hfn);
Don't mark pages dirty if KVM bails from the page fault handler without installing a stage-2 mapping, i.e. if the page is guaranteed to not be written by the guest. In addition to being a (very) minor fix, this paves the way for converting RISC-V to use kvm_release_faultin_page(). Signed-off-by: Sean Christopherson <seanjc@google.com> --- arch/riscv/kvm/mmu.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)