| Message ID | 12a50d857773f74f25555e0985480fb565ec8438.1588711355.git.ashish.kalra@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add AMD SEV guest live migration support | expand |
On Tue, May 5, 2020 at 2:17 PM Ashish Kalra <Ashish.Kalra@amd.com> wrote: > > From: Brijesh Singh <Brijesh.Singh@amd.com> > > This hypercall is used by the SEV guest to notify a change in the page > encryption status to the hypervisor. The hypercall should be invoked > only when the encryption attribute is changed from encrypted -> decrypted > and vice versa. By default all guest pages are considered encrypted. > > Cc: Thomas Gleixner <tglx@linutronix.de> > Cc: Ingo Molnar <mingo@redhat.com> > Cc: "H. Peter Anvin" <hpa@zytor.com> > Cc: Paolo Bonzini <pbonzini@redhat.com> > Cc: "Radim Krčmář" <rkrcmar@redhat.com> > Cc: Joerg Roedel <joro@8bytes.org> > Cc: Borislav Petkov <bp@suse.de> > Cc: Tom Lendacky <thomas.lendacky@amd.com> > Cc: x86@kernel.org > Cc: kvm@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Reviewed-by: Venu Busireddy <venu.busireddy@oracle.com> > Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> > Signed-off-by: Ashish Kalra <ashish.kalra@amd.com> > --- > Documentation/virt/kvm/hypercalls.rst | 15 +++++ > arch/x86/include/asm/kvm_host.h | 2 + > arch/x86/kvm/svm/sev.c | 90 +++++++++++++++++++++++++++ > arch/x86/kvm/svm/svm.c | 2 + > arch/x86/kvm/svm/svm.h | 4 ++ > arch/x86/kvm/vmx/vmx.c | 1 + > arch/x86/kvm/x86.c | 6 ++ > include/uapi/linux/kvm_para.h | 1 + > 8 files changed, 121 insertions(+) > > diff --git a/Documentation/virt/kvm/hypercalls.rst b/Documentation/virt/kvm/hypercalls.rst > index dbaf207e560d..ff5287e68e81 100644 > --- a/Documentation/virt/kvm/hypercalls.rst > +++ b/Documentation/virt/kvm/hypercalls.rst > @@ -169,3 +169,18 @@ a0: destination APIC ID > > :Usage example: When sending a call-function IPI-many to vCPUs, yield if > any of the IPI target vCPUs was preempted. > + > + > +8. KVM_HC_PAGE_ENC_STATUS > +------------------------- > +:Architecture: x86 > +:Status: active > +:Purpose: Notify the encryption status changes in guest page table (SEV guest) > + > +a0: the guest physical address of the start page > +a1: the number of pages > +a2: encryption attribute > + > + Where: > + * 1: Encryption attribute is set > + * 0: Encryption attribute is cleared > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h > index 42a2d0d3984a..4a8ee22f4f5b 100644 > --- a/arch/x86/include/asm/kvm_host.h > +++ b/arch/x86/include/asm/kvm_host.h > @@ -1254,6 +1254,8 @@ struct kvm_x86_ops { > > bool (*apic_init_signal_blocked)(struct kvm_vcpu *vcpu); > int (*enable_direct_tlbflush)(struct kvm_vcpu *vcpu); > + int (*page_enc_status_hc)(struct kvm *kvm, unsigned long gpa, > + unsigned long sz, unsigned long mode); > }; > > struct kvm_x86_init_ops { > diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c > index 698704defbcd..f088467708f0 100644 > --- a/arch/x86/kvm/svm/sev.c > +++ b/arch/x86/kvm/svm/sev.c > @@ -1347,6 +1347,93 @@ static int sev_receive_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) > return ret; > } > > +static int sev_resize_page_enc_bitmap(struct kvm *kvm, unsigned long new_size) > +{ > + struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; > + unsigned long *map; > + unsigned long sz; > + > + if (sev->page_enc_bmap_size >= new_size) > + return 0; > + > + sz = ALIGN(new_size, BITS_PER_LONG) / 8; > + > + map = vmalloc(sz); > + if (!map) { > + pr_err_once("Failed to allocate encrypted bitmap size %lx\n", > + sz); > + return -ENOMEM; > + } > + > + /* mark the page encrypted (by default) */ > + memset(map, 0xff, sz); > + > + bitmap_copy(map, sev->page_enc_bmap, sev->page_enc_bmap_size); > + kvfree(sev->page_enc_bmap); > + > + sev->page_enc_bmap = map; > + sev->page_enc_bmap_size = new_size; > + > + return 0; > +} > + > +int svm_page_enc_status_hc(struct kvm *kvm, unsigned long gpa, > + unsigned long npages, unsigned long enc) > +{ > + struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; > + kvm_pfn_t pfn_start, pfn_end; > + gfn_t gfn_start, gfn_end; > + > + if (!sev_guest(kvm)) > + return -EINVAL; > + > + if (!npages) > + return 0; > + > + gfn_start = gpa_to_gfn(gpa); > + gfn_end = gfn_start + npages; > + > + /* out of bound access error check */ > + if (gfn_end <= gfn_start) > + return -EINVAL; > + > + /* lets make sure that gpa exist in our memslot */ > + pfn_start = gfn_to_pfn(kvm, gfn_start); > + pfn_end = gfn_to_pfn(kvm, gfn_end); > + > + if (is_error_noslot_pfn(pfn_start) && !is_noslot_pfn(pfn_start)) { > + /* > + * Allow guest MMIO range(s) to be added > + * to the page encryption bitmap. > + */ > + return -EINVAL; > + } > + > + if (is_error_noslot_pfn(pfn_end) && !is_noslot_pfn(pfn_end)) { > + /* > + * Allow guest MMIO range(s) to be added > + * to the page encryption bitmap. > + */ > + return -EINVAL; > + } > + > + mutex_lock(&kvm->lock); > + > + if (sev->page_enc_bmap_size < gfn_end) > + goto unlock; > + > + if (enc) > + __bitmap_set(sev->page_enc_bmap, gfn_start, > + gfn_end - gfn_start); > + else > + __bitmap_clear(sev->page_enc_bmap, gfn_start, > + gfn_end - gfn_start); > + > +unlock: > + mutex_unlock(&kvm->lock); > + return 0; > +} > + > int svm_mem_enc_op(struct kvm *kvm, void __user *argp) > { > struct kvm_sev_cmd sev_cmd; > @@ -1560,6 +1647,9 @@ void sev_vm_destroy(struct kvm *kvm) > > sev_unbind_asid(kvm, sev->handle); > sev_asid_free(sev->asid); > + > + kvfree(sev->page_enc_bmap); > + sev->page_enc_bmap = NULL; > } > > int __init sev_hardware_setup(void) > diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c > index 2f379bacbb26..1013ef0f4ce2 100644 > --- a/arch/x86/kvm/svm/svm.c > +++ b/arch/x86/kvm/svm/svm.c > @@ -4014,6 +4014,8 @@ static struct kvm_x86_ops svm_x86_ops __initdata = { > .apic_init_signal_blocked = svm_apic_init_signal_blocked, > > .check_nested_events = svm_check_nested_events, > + > + .page_enc_status_hc = svm_page_enc_status_hc, > }; > > static struct kvm_x86_init_ops svm_init_ops __initdata = { > diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h > index df3474f4fb02..6a562f5928a2 100644 > --- a/arch/x86/kvm/svm/svm.h > +++ b/arch/x86/kvm/svm/svm.h > @@ -65,6 +65,8 @@ struct kvm_sev_info { > int fd; /* SEV device fd */ > unsigned long pages_locked; /* Number of pages locked */ > struct list_head regions_list; /* List of registered regions */ > + unsigned long *page_enc_bmap; > + unsigned long page_enc_bmap_size; > }; > > struct kvm_svm { > @@ -400,6 +402,8 @@ int nested_svm_check_exception(struct vcpu_svm *svm, unsigned nr, > bool has_error_code, u32 error_code); > int svm_check_nested_events(struct kvm_vcpu *vcpu); > int nested_svm_exit_special(struct vcpu_svm *svm); > +int svm_page_enc_status_hc(struct kvm *kvm, unsigned long gpa, > + unsigned long npages, unsigned long enc); > > /* avic.c */ > > diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c > index c2c6335a998c..7d01d3aa6461 100644 > --- a/arch/x86/kvm/vmx/vmx.c > +++ b/arch/x86/kvm/vmx/vmx.c > @@ -7838,6 +7838,7 @@ static struct kvm_x86_ops vmx_x86_ops __initdata = { > .nested_get_evmcs_version = NULL, > .need_emulation_on_page_fault = vmx_need_emulation_on_page_fault, > .apic_init_signal_blocked = vmx_apic_init_signal_blocked, > + .page_enc_status_hc = NULL, > }; > > static __init int hardware_setup(void) > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index c5835f9cb9ad..5f5ddb5765e2 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -7605,6 +7605,12 @@ int kvm_emulate_hypercall(struct kvm_vcpu *vcpu) > kvm_sched_yield(vcpu->kvm, a0); > ret = 0; > break; > + case KVM_HC_PAGE_ENC_STATUS: > + ret = -KVM_ENOSYS; > + if (kvm_x86_ops.page_enc_status_hc) > + ret = kvm_x86_ops.page_enc_status_hc(vcpu->kvm, > + a0, a1, a2); > + break; > default: > ret = -KVM_ENOSYS; > break; > diff --git a/include/uapi/linux/kvm_para.h b/include/uapi/linux/kvm_para.h > index 8b86609849b9..847b83b75dc8 100644 > --- a/include/uapi/linux/kvm_para.h > +++ b/include/uapi/linux/kvm_para.h > @@ -29,6 +29,7 @@ > #define KVM_HC_CLOCK_PAIRING 9 > #define KVM_HC_SEND_IPI 10 > #define KVM_HC_SCHED_YIELD 11 > +#define KVM_HC_PAGE_ENC_STATUS 12 > > /* > * hypercalls use architecture specific > -- > 2.17.1 > Reviewed-by: Steve Rutherford <srutherford@google.com>
diff --git a/Documentation/virt/kvm/hypercalls.rst b/Documentation/virt/kvm/hypercalls.rst index dbaf207e560d..ff5287e68e81 100644 --- a/Documentation/virt/kvm/hypercalls.rst +++ b/Documentation/virt/kvm/hypercalls.rst @@ -169,3 +169,18 @@ a0: destination APIC ID :Usage example: When sending a call-function IPI-many to vCPUs, yield if any of the IPI target vCPUs was preempted. + + +8. KVM_HC_PAGE_ENC_STATUS +------------------------- +:Architecture: x86 +:Status: active +:Purpose: Notify the encryption status changes in guest page table (SEV guest) + +a0: the guest physical address of the start page +a1: the number of pages +a2: encryption attribute + + Where: + * 1: Encryption attribute is set + * 0: Encryption attribute is cleared diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 42a2d0d3984a..4a8ee22f4f5b 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1254,6 +1254,8 @@ struct kvm_x86_ops { bool (*apic_init_signal_blocked)(struct kvm_vcpu *vcpu); int (*enable_direct_tlbflush)(struct kvm_vcpu *vcpu); + int (*page_enc_status_hc)(struct kvm *kvm, unsigned long gpa, + unsigned long sz, unsigned long mode); }; struct kvm_x86_init_ops { diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 698704defbcd..f088467708f0 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -1347,6 +1347,93 @@ static int sev_receive_finish(struct kvm *kvm, struct kvm_sev_cmd *argp) return ret; } +static int sev_resize_page_enc_bitmap(struct kvm *kvm, unsigned long new_size) +{ + struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; + unsigned long *map; + unsigned long sz; + + if (sev->page_enc_bmap_size >= new_size) + return 0; + + sz = ALIGN(new_size, BITS_PER_LONG) / 8; + + map = vmalloc(sz); + if (!map) { + pr_err_once("Failed to allocate encrypted bitmap size %lx\n", + sz); + return -ENOMEM; + } + + /* mark the page encrypted (by default) */ + memset(map, 0xff, sz); + + bitmap_copy(map, sev->page_enc_bmap, sev->page_enc_bmap_size); + kvfree(sev->page_enc_bmap); + + sev->page_enc_bmap = map; + sev->page_enc_bmap_size = new_size; + + return 0; +} + +int svm_page_enc_status_hc(struct kvm *kvm, unsigned long gpa, + unsigned long npages, unsigned long enc) +{ + struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; + kvm_pfn_t pfn_start, pfn_end; + gfn_t gfn_start, gfn_end; + + if (!sev_guest(kvm)) + return -EINVAL; + + if (!npages) + return 0; + + gfn_start = gpa_to_gfn(gpa); + gfn_end = gfn_start + npages; + + /* out of bound access error check */ + if (gfn_end <= gfn_start) + return -EINVAL; + + /* lets make sure that gpa exist in our memslot */ + pfn_start = gfn_to_pfn(kvm, gfn_start); + pfn_end = gfn_to_pfn(kvm, gfn_end); + + if (is_error_noslot_pfn(pfn_start) && !is_noslot_pfn(pfn_start)) { + /* + * Allow guest MMIO range(s) to be added + * to the page encryption bitmap. + */ + return -EINVAL; + } + + if (is_error_noslot_pfn(pfn_end) && !is_noslot_pfn(pfn_end)) { + /* + * Allow guest MMIO range(s) to be added + * to the page encryption bitmap. + */ + return -EINVAL; + } + + mutex_lock(&kvm->lock); + + if (sev->page_enc_bmap_size < gfn_end) + goto unlock; + + if (enc) + __bitmap_set(sev->page_enc_bmap, gfn_start, + gfn_end - gfn_start); + else + __bitmap_clear(sev->page_enc_bmap, gfn_start, + gfn_end - gfn_start); + +unlock: + mutex_unlock(&kvm->lock); + return 0; +} + int svm_mem_enc_op(struct kvm *kvm, void __user *argp) { struct kvm_sev_cmd sev_cmd; @@ -1560,6 +1647,9 @@ void sev_vm_destroy(struct kvm *kvm) sev_unbind_asid(kvm, sev->handle); sev_asid_free(sev->asid); + + kvfree(sev->page_enc_bmap); + sev->page_enc_bmap = NULL; } int __init sev_hardware_setup(void) diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 2f379bacbb26..1013ef0f4ce2 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -4014,6 +4014,8 @@ static struct kvm_x86_ops svm_x86_ops __initdata = { .apic_init_signal_blocked = svm_apic_init_signal_blocked, .check_nested_events = svm_check_nested_events, + + .page_enc_status_hc = svm_page_enc_status_hc, }; static struct kvm_x86_init_ops svm_init_ops __initdata = { diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h index df3474f4fb02..6a562f5928a2 100644 --- a/arch/x86/kvm/svm/svm.h +++ b/arch/x86/kvm/svm/svm.h @@ -65,6 +65,8 @@ struct kvm_sev_info { int fd; /* SEV device fd */ unsigned long pages_locked; /* Number of pages locked */ struct list_head regions_list; /* List of registered regions */ + unsigned long *page_enc_bmap; + unsigned long page_enc_bmap_size; }; struct kvm_svm { @@ -400,6 +402,8 @@ int nested_svm_check_exception(struct vcpu_svm *svm, unsigned nr, bool has_error_code, u32 error_code); int svm_check_nested_events(struct kvm_vcpu *vcpu); int nested_svm_exit_special(struct vcpu_svm *svm); +int svm_page_enc_status_hc(struct kvm *kvm, unsigned long gpa, + unsigned long npages, unsigned long enc); /* avic.c */ diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index c2c6335a998c..7d01d3aa6461 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -7838,6 +7838,7 @@ static struct kvm_x86_ops vmx_x86_ops __initdata = { .nested_get_evmcs_version = NULL, .need_emulation_on_page_fault = vmx_need_emulation_on_page_fault, .apic_init_signal_blocked = vmx_apic_init_signal_blocked, + .page_enc_status_hc = NULL, }; static __init int hardware_setup(void) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index c5835f9cb9ad..5f5ddb5765e2 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -7605,6 +7605,12 @@ int kvm_emulate_hypercall(struct kvm_vcpu *vcpu) kvm_sched_yield(vcpu->kvm, a0); ret = 0; break; + case KVM_HC_PAGE_ENC_STATUS: + ret = -KVM_ENOSYS; + if (kvm_x86_ops.page_enc_status_hc) + ret = kvm_x86_ops.page_enc_status_hc(vcpu->kvm, + a0, a1, a2); + break; default: ret = -KVM_ENOSYS; break; diff --git a/include/uapi/linux/kvm_para.h b/include/uapi/linux/kvm_para.h index 8b86609849b9..847b83b75dc8 100644 --- a/include/uapi/linux/kvm_para.h +++ b/include/uapi/linux/kvm_para.h @@ -29,6 +29,7 @@ #define KVM_HC_CLOCK_PAIRING 9 #define KVM_HC_SEND_IPI 10 #define KVM_HC_SCHED_YIELD 11 +#define KVM_HC_PAGE_ENC_STATUS 12 /* * hypercalls use architecture specific