diff options
| author | Paolo Bonzini <pbonzini@redhat.com> | 2021-08-04 12:48:41 -0400 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-08-05 03:31:40 -0400 |
| commit | 319afe68567b923e25140e744e7f05e3e5d889c1 (patch) | |
| tree | 532621d701e4777a892a98fdc7a31d9f39b5ce7e /arch/x86/kvm/xen.c | |
| parent | e79f49c37ccf273c8aba733f803b3774ebfbe581 (diff) | |
KVM: xen: do not use struct gfn_to_hva_cache
gfn_to_hva_cache is not thread-safe, so it is usually used only within
a vCPU (whose code is protected by vcpu->mutex). The Xen interface
implementation has such a cache in kvm->arch, but it is not really
used except to store the location of the shared info page. Replace
shinfo_set and shinfo_cache with just the value that is passed via
KVM_XEN_ATTR_TYPE_SHARED_INFO; the only complication is that the
initialization value is not zero anymore and therefore kvm_xen_init_vm
needs to be introduced.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/xen.c')
| -rw-r--r-- | arch/x86/kvm/xen.c | 23 |
1 files changed, 12 insertions, 11 deletions
diff --git a/arch/x86/kvm/xen.c b/arch/x86/kvm/xen.c index ae17250e1efe..9ea9c3dabe37 100644 --- a/arch/x86/kvm/xen.c +++ b/arch/x86/kvm/xen.c @@ -25,15 +25,14 @@ static int kvm_xen_shared_info_init(struct kvm *kvm, gfn_t gfn) { gpa_t gpa = gfn_to_gpa(gfn); int wc_ofs, sec_hi_ofs; - int ret; + int ret = 0; int idx = srcu_read_lock(&kvm->srcu); - ret = kvm_gfn_to_hva_cache_init(kvm, &kvm->arch.xen.shinfo_cache, - gpa, PAGE_SIZE); - if (ret) + if (kvm_is_error_hva(gfn_to_hva(kvm, gfn))) { + ret = -EFAULT; goto out; - - kvm->arch.xen.shinfo_set = true; + } + kvm->arch.xen.shinfo_gfn = gfn; /* Paranoia checks on the 32-bit struct layout */ BUILD_BUG_ON(offsetof(struct compat_shared_info, wc) != 0x900); @@ -245,7 +244,7 @@ int kvm_xen_hvm_set_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data) case KVM_XEN_ATTR_TYPE_SHARED_INFO: if (data->u.shared_info.gfn == GPA_INVALID) { - kvm->arch.xen.shinfo_set = false; + kvm->arch.xen.shinfo_gfn = GPA_INVALID; r = 0; break; } @@ -283,10 +282,7 @@ int kvm_xen_hvm_get_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data) break; case KVM_XEN_ATTR_TYPE_SHARED_INFO: - if (kvm->arch.xen.shinfo_set) - data->u.shared_info.gfn = gpa_to_gfn(kvm->arch.xen.shinfo_cache.gpa); - else - data->u.shared_info.gfn = GPA_INVALID; + data->u.shared_info.gfn = gpa_to_gfn(kvm->arch.xen.shinfo_gfn); r = 0; break; @@ -646,6 +642,11 @@ int kvm_xen_hvm_config(struct kvm *kvm, struct kvm_xen_hvm_config *xhc) return 0; } +void kvm_xen_init_vm(struct kvm *kvm) +{ + kvm->arch.xen.shinfo_gfn = GPA_INVALID; +} + void kvm_xen_destroy_vm(struct kvm *kvm) { if (kvm->arch.xen_hvm_config.msr) |