| Message ID | 40272f7b19bd179b094ac1305c787f7e5002c068.1588711355.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 2:18 PM Ashish Kalra <Ashish.Kalra@amd.com> wrote: > > From: Brijesh Singh <Brijesh.Singh@amd.com> > > Invoke a hypercall when a memory region is changed from encrypted -> > decrypted and vice versa. Hypervisor needs to know the page encryption > status during the guest migration. > > 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> > --- > arch/x86/include/asm/paravirt.h | 10 +++++ > arch/x86/include/asm/paravirt_types.h | 2 + > arch/x86/kernel/paravirt.c | 1 + > arch/x86/mm/mem_encrypt.c | 57 ++++++++++++++++++++++++++- > arch/x86/mm/pat/set_memory.c | 7 ++++ > 5 files changed, 76 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h > index 694d8daf4983..8127b9c141bf 100644 > --- a/arch/x86/include/asm/paravirt.h > +++ b/arch/x86/include/asm/paravirt.h > @@ -78,6 +78,12 @@ static inline void paravirt_arch_exit_mmap(struct mm_struct *mm) > PVOP_VCALL1(mmu.exit_mmap, mm); > } > > +static inline void page_encryption_changed(unsigned long vaddr, int npages, > + bool enc) > +{ > + PVOP_VCALL3(mmu.page_encryption_changed, vaddr, npages, enc); > +} > + > #ifdef CONFIG_PARAVIRT_XXL > static inline void load_sp0(unsigned long sp0) > { > @@ -946,6 +952,10 @@ static inline void paravirt_arch_dup_mmap(struct mm_struct *oldmm, > static inline void paravirt_arch_exit_mmap(struct mm_struct *mm) > { > } > + > +static inline void page_encryption_changed(unsigned long vaddr, int npages, bool enc) > +{ > +} > #endif > #endif /* __ASSEMBLY__ */ > #endif /* _ASM_X86_PARAVIRT_H */ > diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h > index 732f62e04ddb..03bfd515c59c 100644 > --- a/arch/x86/include/asm/paravirt_types.h > +++ b/arch/x86/include/asm/paravirt_types.h > @@ -215,6 +215,8 @@ struct pv_mmu_ops { > > /* Hook for intercepting the destruction of an mm_struct. */ > void (*exit_mmap)(struct mm_struct *mm); > + void (*page_encryption_changed)(unsigned long vaddr, int npages, > + bool enc); > > #ifdef CONFIG_PARAVIRT_XXL > struct paravirt_callee_save read_cr2; > diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c > index c131ba4e70ef..840c02b23aeb 100644 > --- a/arch/x86/kernel/paravirt.c > +++ b/arch/x86/kernel/paravirt.c > @@ -367,6 +367,7 @@ struct paravirt_patch_template pv_ops = { > (void (*)(struct mmu_gather *, void *))tlb_remove_page, > > .mmu.exit_mmap = paravirt_nop, > + .mmu.page_encryption_changed = paravirt_nop, > > #ifdef CONFIG_PARAVIRT_XXL > .mmu.read_cr2 = __PV_IS_CALLEE_SAVE(native_read_cr2), > diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c > index f4bd4b431ba1..c9800fa811f6 100644 > --- a/arch/x86/mm/mem_encrypt.c > +++ b/arch/x86/mm/mem_encrypt.c > @@ -19,6 +19,7 @@ > #include <linux/kernel.h> > #include <linux/bitops.h> > #include <linux/dma-mapping.h> > +#include <linux/kvm_para.h> > > #include <asm/tlbflush.h> > #include <asm/fixmap.h> > @@ -29,6 +30,7 @@ > #include <asm/processor-flags.h> > #include <asm/msr.h> > #include <asm/cmdline.h> > +#include <asm/kvm_para.h> > > #include "mm_internal.h" > > @@ -196,6 +198,47 @@ void __init sme_early_init(void) > swiotlb_force = SWIOTLB_FORCE; > } > > +static void set_memory_enc_dec_hypercall(unsigned long vaddr, int npages, > + bool enc) > +{ > + unsigned long sz = npages << PAGE_SHIFT; > + unsigned long vaddr_end, vaddr_next; > + > + vaddr_end = vaddr + sz; > + > + for (; vaddr < vaddr_end; vaddr = vaddr_next) { > + int psize, pmask, level; > + unsigned long pfn; > + pte_t *kpte; > + > + kpte = lookup_address(vaddr, &level); > + if (!kpte || pte_none(*kpte)) > + return; > + > + switch (level) { > + case PG_LEVEL_4K: > + pfn = pte_pfn(*kpte); > + break; > + case PG_LEVEL_2M: > + pfn = pmd_pfn(*(pmd_t *)kpte); > + break; > + case PG_LEVEL_1G: > + pfn = pud_pfn(*(pud_t *)kpte); > + break; > + default: > + return; > + } > + > + psize = page_level_size(level); > + pmask = page_level_mask(level); > + > + kvm_sev_hypercall3(KVM_HC_PAGE_ENC_STATUS, > + pfn << PAGE_SHIFT, psize >> PAGE_SHIFT, enc); > + > + vaddr_next = (vaddr & pmask) + psize; > + } > +} > + > static void __init __set_clr_pte_enc(pte_t *kpte, int level, bool enc) > { > pgprot_t old_prot, new_prot; > @@ -253,12 +296,13 @@ static void __init __set_clr_pte_enc(pte_t *kpte, int level, bool enc) > static int __init early_set_memory_enc_dec(unsigned long vaddr, > unsigned long size, bool enc) > { > - unsigned long vaddr_end, vaddr_next; > + unsigned long vaddr_end, vaddr_next, start; > unsigned long psize, pmask; > int split_page_size_mask; > int level, ret; > pte_t *kpte; > > + start = vaddr; > vaddr_next = vaddr; > vaddr_end = vaddr + size; > > @@ -313,6 +357,8 @@ static int __init early_set_memory_enc_dec(unsigned long vaddr, > > ret = 0; > > + set_memory_enc_dec_hypercall(start, PAGE_ALIGN(size) >> PAGE_SHIFT, > + enc); > out: > __flush_tlb_all(); > return ret; > @@ -451,6 +497,15 @@ void __init mem_encrypt_init(void) > if (sev_active()) > static_branch_enable(&sev_enable_key); > > +#ifdef CONFIG_PARAVIRT > + /* > + * With SEV, we need to make a hypercall when page encryption state is > + * changed. > + */ > + if (sev_active()) > + pv_ops.mmu.page_encryption_changed = set_memory_enc_dec_hypercall; > +#endif > + > pr_info("AMD %s active\n", > sev_active() ? "Secure Encrypted Virtualization (SEV)" > : "Secure Memory Encryption (SME)"); > diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c > index 59eca6a94ce7..9aaf1b6f5a1b 100644 > --- a/arch/x86/mm/pat/set_memory.c > +++ b/arch/x86/mm/pat/set_memory.c > @@ -27,6 +27,7 @@ > #include <asm/proto.h> > #include <asm/memtype.h> > #include <asm/set_memory.h> > +#include <asm/paravirt.h> > > #include "../mm_internal.h" > > @@ -2003,6 +2004,12 @@ static int __set_memory_enc_dec(unsigned long addr, int numpages, bool enc) > */ > cpa_flush(&cpa, 0); > > + /* Notify hypervisor that a given memory range is mapped encrypted > + * or decrypted. The hypervisor will use this information during the > + * VM migration. > + */ > + page_encryption_changed(addr, numpages, enc); > + > return ret; > } > > -- > 2.17.1 > Reviewed-by: Steve Rutherford <srutherford@google.com>
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h index 694d8daf4983..8127b9c141bf 100644 --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -78,6 +78,12 @@ static inline void paravirt_arch_exit_mmap(struct mm_struct *mm) PVOP_VCALL1(mmu.exit_mmap, mm); } +static inline void page_encryption_changed(unsigned long vaddr, int npages, + bool enc) +{ + PVOP_VCALL3(mmu.page_encryption_changed, vaddr, npages, enc); +} + #ifdef CONFIG_PARAVIRT_XXL static inline void load_sp0(unsigned long sp0) { @@ -946,6 +952,10 @@ static inline void paravirt_arch_dup_mmap(struct mm_struct *oldmm, static inline void paravirt_arch_exit_mmap(struct mm_struct *mm) { } + +static inline void page_encryption_changed(unsigned long vaddr, int npages, bool enc) +{ +} #endif #endif /* __ASSEMBLY__ */ #endif /* _ASM_X86_PARAVIRT_H */ diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h index 732f62e04ddb..03bfd515c59c 100644 --- a/arch/x86/include/asm/paravirt_types.h +++ b/arch/x86/include/asm/paravirt_types.h @@ -215,6 +215,8 @@ struct pv_mmu_ops { /* Hook for intercepting the destruction of an mm_struct. */ void (*exit_mmap)(struct mm_struct *mm); + void (*page_encryption_changed)(unsigned long vaddr, int npages, + bool enc); #ifdef CONFIG_PARAVIRT_XXL struct paravirt_callee_save read_cr2; diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c index c131ba4e70ef..840c02b23aeb 100644 --- a/arch/x86/kernel/paravirt.c +++ b/arch/x86/kernel/paravirt.c @@ -367,6 +367,7 @@ struct paravirt_patch_template pv_ops = { (void (*)(struct mmu_gather *, void *))tlb_remove_page, .mmu.exit_mmap = paravirt_nop, + .mmu.page_encryption_changed = paravirt_nop, #ifdef CONFIG_PARAVIRT_XXL .mmu.read_cr2 = __PV_IS_CALLEE_SAVE(native_read_cr2), diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c index f4bd4b431ba1..c9800fa811f6 100644 --- a/arch/x86/mm/mem_encrypt.c +++ b/arch/x86/mm/mem_encrypt.c @@ -19,6 +19,7 @@ #include <linux/kernel.h> #include <linux/bitops.h> #include <linux/dma-mapping.h> +#include <linux/kvm_para.h> #include <asm/tlbflush.h> #include <asm/fixmap.h> @@ -29,6 +30,7 @@ #include <asm/processor-flags.h> #include <asm/msr.h> #include <asm/cmdline.h> +#include <asm/kvm_para.h> #include "mm_internal.h" @@ -196,6 +198,47 @@ void __init sme_early_init(void) swiotlb_force = SWIOTLB_FORCE; } +static void set_memory_enc_dec_hypercall(unsigned long vaddr, int npages, + bool enc) +{ + unsigned long sz = npages << PAGE_SHIFT; + unsigned long vaddr_end, vaddr_next; + + vaddr_end = vaddr + sz; + + for (; vaddr < vaddr_end; vaddr = vaddr_next) { + int psize, pmask, level; + unsigned long pfn; + pte_t *kpte; + + kpte = lookup_address(vaddr, &level); + if (!kpte || pte_none(*kpte)) + return; + + switch (level) { + case PG_LEVEL_4K: + pfn = pte_pfn(*kpte); + break; + case PG_LEVEL_2M: + pfn = pmd_pfn(*(pmd_t *)kpte); + break; + case PG_LEVEL_1G: + pfn = pud_pfn(*(pud_t *)kpte); + break; + default: + return; + } + + psize = page_level_size(level); + pmask = page_level_mask(level); + + kvm_sev_hypercall3(KVM_HC_PAGE_ENC_STATUS, + pfn << PAGE_SHIFT, psize >> PAGE_SHIFT, enc); + + vaddr_next = (vaddr & pmask) + psize; + } +} + static void __init __set_clr_pte_enc(pte_t *kpte, int level, bool enc) { pgprot_t old_prot, new_prot; @@ -253,12 +296,13 @@ static void __init __set_clr_pte_enc(pte_t *kpte, int level, bool enc) static int __init early_set_memory_enc_dec(unsigned long vaddr, unsigned long size, bool enc) { - unsigned long vaddr_end, vaddr_next; + unsigned long vaddr_end, vaddr_next, start; unsigned long psize, pmask; int split_page_size_mask; int level, ret; pte_t *kpte; + start = vaddr; vaddr_next = vaddr; vaddr_end = vaddr + size; @@ -313,6 +357,8 @@ static int __init early_set_memory_enc_dec(unsigned long vaddr, ret = 0; + set_memory_enc_dec_hypercall(start, PAGE_ALIGN(size) >> PAGE_SHIFT, + enc); out: __flush_tlb_all(); return ret; @@ -451,6 +497,15 @@ void __init mem_encrypt_init(void) if (sev_active()) static_branch_enable(&sev_enable_key); +#ifdef CONFIG_PARAVIRT + /* + * With SEV, we need to make a hypercall when page encryption state is + * changed. + */ + if (sev_active()) + pv_ops.mmu.page_encryption_changed = set_memory_enc_dec_hypercall; +#endif + pr_info("AMD %s active\n", sev_active() ? "Secure Encrypted Virtualization (SEV)" : "Secure Memory Encryption (SME)"); diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c index 59eca6a94ce7..9aaf1b6f5a1b 100644 --- a/arch/x86/mm/pat/set_memory.c +++ b/arch/x86/mm/pat/set_memory.c @@ -27,6 +27,7 @@ #include <asm/proto.h> #include <asm/memtype.h> #include <asm/set_memory.h> +#include <asm/paravirt.h> #include "../mm_internal.h" @@ -2003,6 +2004,12 @@ static int __set_memory_enc_dec(unsigned long addr, int numpages, bool enc) */ cpa_flush(&cpa, 0); + /* Notify hypervisor that a given memory range is mapped encrypted + * or decrypted. The hypervisor will use this information during the + * VM migration. + */ + page_encryption_changed(addr, numpages, enc); + return ret; }