Introduce CONFIG_NESTED_VIRT (default n) to allow nested virtualization support to be disabled at build time. This is useful for embedded or safety-focused deployments where nested virtualization is not needed, reducing code size and attack surface.
When CONFIG_NESTED_VIRT=n, the following source files are excluded: - arch/x86/hvm/nestedhvm.c - arch/x86/hvm/svm/nestedsvm.c - arch/x86/hvm/vmx/vvmx.c - arch/x86/mm/nested.c - arch/x86/mm/hap/nested_hap.c - arch/x86/mm/hap/nested_ept.c Add inline stubs where needed in headers. Guard assembly code paths for nested virt with #ifdef CONFIG_NESTED_VIRT. Move exception injection for VMX/SVM instructions to the callers in vmx.c/svm.c to avoid header dependency issues in the stubs. No functional change when CONFIG_NESTED_VIRT=y. Signed-off-by: Stefano Stabellini <[email protected]> --- Changes in v3: - Kconfig: Change "depends on AMD_SVM || INTEL_VMX" to "depends on HVM" - Kconfig: Remove redundant "default n" line - Kconfig: Remove "If unsure, say N." from help text - mm/hap/Makefile: Simplify using intermediate nested-y variable: nested-y := nested_hap.o nested-$(CONFIG_INTEL_VMX) += nested_ept.o obj-$(CONFIG_NESTED_VIRT) += $(nested-y) - svm/nestedhvm.h: Remove #ifdef CONFIG_NESTED_VIRT stubs, keep only function declarations (the functions are only called from code that is already compiled out when nested virt is disabled) - svm/nestedhvm.h: Add CONFIG_NESTED_VIRT guard to nsvm_efer_svm_enabled macro to return false when nested virt is disabled - svm/svm.c: Move #UD injection for STGI/CLGI to the caller instead of stub functions, checking nestedhvm_enabled()/nsvm_efer_svm_enabled() - svm/svm.c: Mark svm_vmexit_do_vmrun/vmload/vmsave as __maybe_unused - svm/svm.c: Remove empty nsvm_vcpu_switch stub (now guarded in asm) - svm/entry.S: Add #ifdef CONFIG_NESTED_VIRT guards around nested virt specific code paths - vmx/vmx.c: Remove empty nvmx_switch_guest stub (now guarded in asm) - vmx/vmx.c: Move nvmx_enqueue_n2_exceptions and nvmx_vmexit_event to vvmx.c where they belong - vmx/vvmx.h: Add declarations for nvmx_vmexit_event and nvmx_enqueue_n2_exceptions - vmx/vvmx.h: Fix nvmx_msr_read_intercept stub comment - vmx/vvmx.h: nvmx_handle_vmx_insn stub returns X86EMUL_EXCEPTION with ASSERT_UNREACHABLE (caller handles injection) - vmx/vvmx.h: Convert get_vvmcs macro to inline function in stubs - vmx/entry.S: Add #ifdef CONFIG_NESTED_VIRT guard around nvmx_switch_guest - nestedhvm.h: Convert macro stubs to proper inline functions --- xen/arch/x86/hvm/Kconfig | 7 +++ xen/arch/x86/hvm/Makefile | 2 +- xen/arch/x86/hvm/svm/Makefile | 2 +- xen/arch/x86/hvm/svm/entry.S | 4 ++ xen/arch/x86/hvm/svm/nestedhvm.h | 2 +- xen/arch/x86/hvm/svm/svm.c | 18 ++++-- xen/arch/x86/hvm/vmx/Makefile | 2 +- xen/arch/x86/hvm/vmx/entry.S | 2 + xen/arch/x86/hvm/vmx/vmx.c | 31 +--------- xen/arch/x86/hvm/vmx/vvmx.c | 26 +++++++++ xen/arch/x86/include/asm/hvm/hvm.h | 2 +- xen/arch/x86/include/asm/hvm/nestedhvm.h | 64 +++++++++++++++++--- xen/arch/x86/include/asm/hvm/vmx/vvmx.h | 74 ++++++++++++++++++++++++ xen/arch/x86/mm/Makefile | 2 +- xen/arch/x86/mm/hap/Makefile | 5 +- xen/arch/x86/mm/p2m.h | 6 ++ xen/arch/x86/sysctl.c | 2 + xen/include/public/sysctl.h | 4 +- 18 files changed, 204 insertions(+), 51 deletions(-) diff --git a/xen/arch/x86/hvm/Kconfig b/xen/arch/x86/hvm/Kconfig index f32bf5cbb7..af661385b5 100644 --- a/xen/arch/x86/hvm/Kconfig +++ b/xen/arch/x86/hvm/Kconfig @@ -92,4 +92,11 @@ config MEM_SHARING bool "Xen memory sharing support (UNSUPPORTED)" if UNSUPPORTED depends on INTEL_VMX +config NESTED_VIRT + bool "Nested virtualization support" + depends on HVM + help + Enable nested virtualization, allowing guests to run their own + hypervisors. This requires hardware support. + endif diff --git a/xen/arch/x86/hvm/Makefile b/xen/arch/x86/hvm/Makefile index f34fb03934..b8a0a68624 100644 --- a/xen/arch/x86/hvm/Makefile +++ b/xen/arch/x86/hvm/Makefile @@ -18,7 +18,7 @@ obj-y += irq.o obj-y += mmio.o obj-$(CONFIG_VM_EVENT) += monitor.o obj-y += mtrr.o -obj-y += nestedhvm.o +obj-$(CONFIG_NESTED_VIRT) += nestedhvm.o obj-y += pmtimer.o obj-y += quirks.o obj-y += rtc.o diff --git a/xen/arch/x86/hvm/svm/Makefile b/xen/arch/x86/hvm/svm/Makefile index 8a072cafd5..92418e3444 100644 --- a/xen/arch/x86/hvm/svm/Makefile +++ b/xen/arch/x86/hvm/svm/Makefile @@ -2,6 +2,6 @@ obj-y += asid.o obj-y += emulate.o obj-bin-y += entry.o obj-y += intr.o -obj-y += nestedsvm.o +obj-$(CONFIG_NESTED_VIRT) += nestedsvm.o obj-y += svm.o obj-y += vmcb.o diff --git a/xen/arch/x86/hvm/svm/entry.S b/xen/arch/x86/hvm/svm/entry.S index af8db23b03..7964c80750 100644 --- a/xen/arch/x86/hvm/svm/entry.S +++ b/xen/arch/x86/hvm/svm/entry.S @@ -28,7 +28,9 @@ FUNC(svm_asm_do_resume) GET_CURRENT(bx) .Lsvm_do_resume: call svm_intr_assist +#ifdef CONFIG_NESTED_VIRT call nsvm_vcpu_switch +#endif ASSERT_NOT_IN_ATOMIC mov VCPU_processor(%rbx),%eax @@ -39,6 +41,7 @@ FUNC(svm_asm_do_resume) cmp %ecx,(%rdx,%rax,1) jne .Lsvm_process_softirqs +#ifdef CONFIG_NESTED_VIRT cmp %cl,VCPU_nsvm_hap_enabled(%rbx) UNLIKELY_START(ne, nsvm_hap) cmp %rcx,VCPU_nhvm_p2m(%rbx) @@ -52,6 +55,7 @@ UNLIKELY_START(ne, nsvm_hap) sti jmp .Lsvm_do_resume __UNLIKELY_END(nsvm_hap) +#endif call svm_vmenter_helper diff --git a/xen/arch/x86/hvm/svm/nestedhvm.h b/xen/arch/x86/hvm/svm/nestedhvm.h index 9bfed5ffd7..5cb85410f8 100644 --- a/xen/arch/x86/hvm/svm/nestedhvm.h +++ b/xen/arch/x86/hvm/svm/nestedhvm.h @@ -24,7 +24,7 @@ /* True when l1 guest enabled SVM in EFER */ #define nsvm_efer_svm_enabled(v) \ - (!!((v)->arch.hvm.guest_efer & EFER_SVME)) + (IS_ENABLED(CONFIG_NESTED_VIRT) && ((v)->arch.hvm.guest_efer & EFER_SVME)) int nestedsvm_vmcb_map(struct vcpu *v, uint64_t vmcbaddr); void nestedsvm_vmexit_defer(struct vcpu *v, diff --git a/xen/arch/x86/hvm/svm/svm.c b/xen/arch/x86/hvm/svm/svm.c index 18ba837738..2cabc89fb5 100644 --- a/xen/arch/x86/hvm/svm/svm.c +++ b/xen/arch/x86/hvm/svm/svm.c @@ -2165,7 +2165,7 @@ static void svm_vmexit_do_pause(struct cpu_user_regs *regs) vcpu_yield(); } -static void +static void __maybe_unused svm_vmexit_do_vmrun(struct cpu_user_regs *regs, struct vcpu *v, uint64_t vmcbaddr) { @@ -2211,7 +2211,7 @@ nsvm_get_nvmcb_page(struct vcpu *v, uint64_t vmcbaddr) return page; } -static void +static void __maybe_unused svm_vmexit_do_vmload(struct vmcb_struct *vmcb, struct cpu_user_regs *regs, struct vcpu *v, uint64_t vmcbaddr) @@ -2246,7 +2246,7 @@ svm_vmexit_do_vmload(struct vmcb_struct *vmcb, __update_guest_eip(regs, inst_len); } -static void +static void __maybe_unused svm_vmexit_do_vmsave(struct vmcb_struct *vmcb, struct cpu_user_regs *regs, struct vcpu *v, uint64_t vmcbaddr) @@ -2465,6 +2465,7 @@ static struct hvm_function_table __initdata_cf_clobber svm_function_table = { .set_rdtsc_exiting = svm_set_rdtsc_exiting, .get_insn_bytes = svm_get_insn_bytes, +#ifdef CONFIG_NESTED_VIRT .nhvm_vcpu_initialise = nsvm_vcpu_initialise, .nhvm_vcpu_destroy = nsvm_vcpu_destroy, .nhvm_vcpu_reset = nsvm_vcpu_reset, @@ -2474,6 +2475,7 @@ static struct hvm_function_table __initdata_cf_clobber svm_function_table = { .nhvm_vmcx_hap_enabled = nsvm_vmcb_hap_enabled, .nhvm_intr_blocked = nsvm_intr_blocked, .nhvm_hap_walk_L1_p2m = nsvm_hap_walk_L1_p2m, +#endif .get_reg = svm_get_reg, .set_reg = svm_set_reg, @@ -3011,10 +3013,16 @@ void asmlinkage svm_vmexit_handler(void) svm_vmexit_do_vmsave(vmcb, regs, v, regs->rax); break; case VMEXIT_STGI: - svm_vmexit_do_stgi(regs, v); + if ( !nestedhvm_enabled(v->domain) ) + hvm_inject_hw_exception(X86_EXC_UD, X86_EVENT_NO_EC); + else + svm_vmexit_do_stgi(regs, v); break; case VMEXIT_CLGI: - svm_vmexit_do_clgi(regs, v); + if ( !nsvm_efer_svm_enabled(v) ) + hvm_inject_hw_exception(X86_EXC_UD, X86_EVENT_NO_EC); + else + svm_vmexit_do_clgi(regs, v); break; case VMEXIT_XSETBV: diff --git a/xen/arch/x86/hvm/vmx/Makefile b/xen/arch/x86/hvm/vmx/Makefile index 04a29ce59d..902564b3e2 100644 --- a/xen/arch/x86/hvm/vmx/Makefile +++ b/xen/arch/x86/hvm/vmx/Makefile @@ -3,4 +3,4 @@ obj-y += intr.o obj-y += realmode.o obj-y += vmcs.o obj-y += vmx.o -obj-y += vvmx.o +obj-$(CONFIG_NESTED_VIRT) += vvmx.o diff --git a/xen/arch/x86/hvm/vmx/entry.S b/xen/arch/x86/hvm/vmx/entry.S index 2bfee715b3..4d62efddf4 100644 --- a/xen/arch/x86/hvm/vmx/entry.S +++ b/xen/arch/x86/hvm/vmx/entry.S @@ -83,7 +83,9 @@ FUNC(vmx_asm_vmexit_handler) .Lvmx_do_vmentry: call vmx_intr_assist +#ifdef CONFIG_NESTED_VIRT call nvmx_switch_guest +#endif ASSERT_NOT_IN_ATOMIC mov VCPU_processor(%rbx),%eax diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c index 82c55f49ae..4e3c8018d2 100644 --- a/xen/arch/x86/hvm/vmx/vmx.c +++ b/xen/arch/x86/hvm/vmx/vmx.c @@ -2014,33 +2014,6 @@ static void cf_check vmx_update_guest_efer(struct vcpu *v) vmx_set_msr_intercept(v, MSR_EFER, VMX_MSR_R); } -static void nvmx_enqueue_n2_exceptions(struct vcpu *v, - unsigned long intr_fields, int error_code, uint8_t source) -{ - struct nestedvmx *nvmx = &vcpu_2_nvmx(v); - - if ( !(nvmx->intr.intr_info & INTR_INFO_VALID_MASK) ) { - /* enqueue the exception till the VMCS switch back to L1 */ - nvmx->intr.intr_info = intr_fields; - nvmx->intr.error_code = error_code; - nvmx->intr.source = source; - vcpu_nestedhvm(v).nv_vmexit_pending = 1; - return; - } - else - gdprintk(XENLOG_ERR, "Double Fault on Nested Guest: exception %lx %x" - "on %lx %x\n", intr_fields, error_code, - nvmx->intr.intr_info, nvmx->intr.error_code); -} - -static int cf_check nvmx_vmexit_event( - struct vcpu *v, const struct x86_event *event) -{ - nvmx_enqueue_n2_exceptions(v, event->vector, event->error_code, - hvm_intsrc_none); - return NESTEDHVM_VMEXIT_DONE; -} - static void __vmx_inject_exception(int trap, int type, int error_code) { unsigned long intr_fields; @@ -2933,6 +2906,7 @@ static struct hvm_function_table __initdata_cf_clobber vmx_function_table = { .handle_cd = vmx_handle_cd, .set_info_guest = vmx_set_info_guest, .set_rdtsc_exiting = vmx_set_rdtsc_exiting, +#ifdef CONFIG_NESTED_VIRT .nhvm_vcpu_initialise = nvmx_vcpu_initialise, .nhvm_vcpu_destroy = nvmx_vcpu_destroy, .nhvm_vcpu_reset = nvmx_vcpu_reset, @@ -2942,8 +2916,9 @@ static struct hvm_function_table __initdata_cf_clobber vmx_function_table = { .nhvm_vcpu_vmexit_event = nvmx_vmexit_event, .nhvm_intr_blocked = nvmx_intr_blocked, .nhvm_domain_relinquish_resources = nvmx_domain_relinquish_resources, - .update_vlapic_mode = vmx_vlapic_msr_changed, .nhvm_hap_walk_L1_p2m = nvmx_hap_walk_L1_p2m, +#endif + .update_vlapic_mode = vmx_vlapic_msr_changed, #ifdef CONFIG_VM_EVENT .enable_msr_interception = vmx_enable_msr_interception, #endif diff --git a/xen/arch/x86/hvm/vmx/vvmx.c b/xen/arch/x86/hvm/vmx/vvmx.c index 38952f0696..2bb42678c5 100644 --- a/xen/arch/x86/hvm/vmx/vvmx.c +++ b/xen/arch/x86/hvm/vmx/vvmx.c @@ -2821,6 +2821,32 @@ void nvmx_set_cr_read_shadow(struct vcpu *v, unsigned int cr) __vmwrite(read_shadow_field, v->arch.hvm.nvcpu.guest_cr[cr]); } +void nvmx_enqueue_n2_exceptions(struct vcpu *v, + unsigned long intr_fields, int error_code, uint8_t source) +{ + struct nestedvmx *nvmx = &vcpu_2_nvmx(v); + + if ( !(nvmx->intr.intr_info & INTR_INFO_VALID_MASK) ) { + /* enqueue the exception till the VMCS switch back to L1 */ + nvmx->intr.intr_info = intr_fields; + nvmx->intr.error_code = error_code; + nvmx->intr.source = source; + vcpu_nestedhvm(v).nv_vmexit_pending = 1; + return; + } + else + gdprintk(XENLOG_ERR, "Double Fault on Nested Guest: exception %lx %x" + "on %lx %x\n", intr_fields, error_code, + nvmx->intr.intr_info, nvmx->intr.error_code); +} + +int cf_check nvmx_vmexit_event(struct vcpu *v, const struct x86_event *event) +{ + nvmx_enqueue_n2_exceptions(v, event->vector, event->error_code, + hvm_intsrc_none); + return NESTEDHVM_VMEXIT_DONE; +} + void __init start_nested_vmx(struct hvm_function_table *hvm_function_table) { /* TODO: Require hardware support before enabling nested virt */ diff --git a/xen/arch/x86/include/asm/hvm/hvm.h b/xen/arch/x86/include/asm/hvm/hvm.h index 7d9774df59..536a38b450 100644 --- a/xen/arch/x86/include/asm/hvm/hvm.h +++ b/xen/arch/x86/include/asm/hvm/hvm.h @@ -711,7 +711,7 @@ static inline bool hvm_altp2m_supported(void) /* Returns true if we have the minimum hardware requirements for nested virt */ static inline bool hvm_nested_virt_supported(void) { - return hvm_funcs.caps.nested_virt; + return IS_ENABLED(CONFIG_NESTED_VIRT) && hvm_funcs.caps.nested_virt; } #ifdef CONFIG_ALTP2M diff --git a/xen/arch/x86/include/asm/hvm/nestedhvm.h b/xen/arch/x86/include/asm/hvm/nestedhvm.h index ea2c1bc328..2f8209271a 100644 --- a/xen/arch/x86/include/asm/hvm/nestedhvm.h +++ b/xen/arch/x86/include/asm/hvm/nestedhvm.h @@ -25,9 +25,21 @@ enum nestedhvm_vmexits { /* Nested HVM on/off per domain */ static inline bool nestedhvm_enabled(const struct domain *d) { - return IS_ENABLED(CONFIG_HVM) && (d->options & XEN_DOMCTL_CDF_nested_virt); + return IS_ENABLED(CONFIG_NESTED_VIRT) && + (d->options & XEN_DOMCTL_CDF_nested_virt); } +/* Nested paging */ +#define NESTEDHVM_PAGEFAULT_DONE 0 +#define NESTEDHVM_PAGEFAULT_INJECT 1 +#define NESTEDHVM_PAGEFAULT_L1_ERROR 2 +#define NESTEDHVM_PAGEFAULT_L0_ERROR 3 +#define NESTEDHVM_PAGEFAULT_MMIO 4 +#define NESTEDHVM_PAGEFAULT_RETRY 5 +#define NESTEDHVM_PAGEFAULT_DIRECT_MMIO 6 + +#ifdef CONFIG_NESTED_VIRT + /* Nested VCPU */ int nestedhvm_vcpu_initialise(struct vcpu *v); void nestedhvm_vcpu_destroy(struct vcpu *v); @@ -38,14 +50,6 @@ bool nestedhvm_vcpu_in_guestmode(struct vcpu *v); #define nestedhvm_vcpu_exit_guestmode(v) \ vcpu_nestedhvm(v).nv_guestmode = 0 -/* Nested paging */ -#define NESTEDHVM_PAGEFAULT_DONE 0 -#define NESTEDHVM_PAGEFAULT_INJECT 1 -#define NESTEDHVM_PAGEFAULT_L1_ERROR 2 -#define NESTEDHVM_PAGEFAULT_L0_ERROR 3 -#define NESTEDHVM_PAGEFAULT_MMIO 4 -#define NESTEDHVM_PAGEFAULT_RETRY 5 -#define NESTEDHVM_PAGEFAULT_DIRECT_MMIO 6 int nestedhvm_hap_nested_page_fault(struct vcpu *v, paddr_t *L2_gpa, struct npfec npfec); @@ -59,6 +63,48 @@ unsigned long *nestedhvm_vcpu_iomap_get(bool ioport_80, bool ioport_ed); void nestedhvm_vmcx_flushtlb(struct p2m_domain *p2m); +#else /* !CONFIG_NESTED_VIRT */ + +static inline int nestedhvm_vcpu_initialise(struct vcpu *v) +{ + ASSERT_UNREACHABLE(); + return -EOPNOTSUPP; +} +static inline void nestedhvm_vcpu_destroy(struct vcpu *v) { } +static inline void nestedhvm_vcpu_reset(struct vcpu *v) +{ + ASSERT_UNREACHABLE(); +} +static inline bool nestedhvm_vcpu_in_guestmode(struct vcpu *v) { return false; } +static inline int nestedhvm_hap_nested_page_fault(struct vcpu *v, paddr_t *L2_gpa, + struct npfec npfec) +{ + ASSERT_UNREACHABLE(); + return NESTEDHVM_PAGEFAULT_L0_ERROR; +} +static inline void nestedhvm_vcpu_enter_guestmode(struct vcpu *v) +{ + ASSERT_UNREACHABLE(); +} +static inline void nestedhvm_vcpu_exit_guestmode(struct vcpu *v) +{ + ASSERT_UNREACHABLE(); +} +static inline bool nestedhvm_paging_mode_hap(struct vcpu *v) +{ + return false; +} +static inline bool nestedhvm_vmswitch_in_progress(struct vcpu *v) +{ + return false; +} +static inline void nestedhvm_vmcx_flushtlb(struct p2m_domain *p2m) +{ + ASSERT_UNREACHABLE(); +} + +#endif /* CONFIG_NESTED_VIRT */ + static inline bool nestedhvm_is_n2(struct vcpu *v) { if ( !nestedhvm_enabled(v->domain) || diff --git a/xen/arch/x86/include/asm/hvm/vmx/vvmx.h b/xen/arch/x86/include/asm/hvm/vmx/vvmx.h index da10d3fa96..d0c1ae29f6 100644 --- a/xen/arch/x86/include/asm/hvm/vmx/vvmx.h +++ b/xen/arch/x86/include/asm/hvm/vmx/vvmx.h @@ -73,6 +73,8 @@ union vmx_inst_info { u32 word; }; +#ifdef CONFIG_NESTED_VIRT + int cf_check nvmx_vcpu_initialise(struct vcpu *v); void cf_check nvmx_vcpu_destroy(struct vcpu *v); int cf_check nvmx_vcpu_reset(struct vcpu *v); @@ -199,5 +201,77 @@ int nept_translate_l2ga(struct vcpu *v, paddr_t l2ga, uint64_t *exit_qual, uint32_t *exit_reason); int nvmx_cpu_up_prepare(unsigned int cpu); void nvmx_cpu_dead(unsigned int cpu); +int cf_check nvmx_vmexit_event(struct vcpu *v, const struct x86_event *event); +void nvmx_enqueue_n2_exceptions(struct vcpu *v, + unsigned long intr_fields, int error_code, uint8_t source); + +#else /* !CONFIG_NESTED_VIRT */ + +static inline void nvmx_update_exec_control(struct vcpu *v, u32 value) +{ + ASSERT_UNREACHABLE(); +} +static inline void nvmx_update_secondary_exec_control(struct vcpu *v, + unsigned long value) +{ + ASSERT_UNREACHABLE(); +} +static inline void nvmx_update_exception_bitmap(struct vcpu *v, + unsigned long value) +{ + ASSERT_UNREACHABLE(); +} +static inline u64 nvmx_get_tsc_offset(struct vcpu *v) +{ + ASSERT_UNREACHABLE(); + return 0; +} +static inline void nvmx_set_cr_read_shadow(struct vcpu *v, unsigned int cr) +{ + ASSERT_UNREACHABLE(); +} +static inline bool nvmx_intercepts_exception(struct vcpu *v, unsigned int vector, + int error_code) +{ + ASSERT_UNREACHABLE(); + return false; +} +static inline int nvmx_n2_vmexit_handler(struct cpu_user_regs *regs, + unsigned int exit_reason) +{ + ASSERT_UNREACHABLE(); + return 0; +} +static inline void nvmx_idtv_handling(void) +{ + ASSERT_UNREACHABLE(); +} +static inline int nvmx_msr_read_intercept(unsigned int msr, u64 *msr_content) +{ + /* return 0 to trigger #GP */ + return 0; +} +static inline int nvmx_handle_vmx_insn(struct cpu_user_regs *regs, + unsigned int exit_reason) +{ + ASSERT_UNREACHABLE(); + return X86EMUL_EXCEPTION; +} +static inline int nvmx_cpu_up_prepare(unsigned int cpu) { return 0; } +static inline void nvmx_cpu_dead(unsigned int cpu) { } +static inline void nvmx_enqueue_n2_exceptions(struct vcpu *v, + unsigned long intr_fields, int error_code, uint8_t source) +{ + ASSERT_UNREACHABLE(); +} + +static inline u64 get_vvmcs(const struct vcpu *vcpu, u32 encoding) +{ + ASSERT_UNREACHABLE(); + return 0; +} + +#endif /* CONFIG_NESTED_VIRT */ + #endif /* __ASM_X86_HVM_VVMX_H__ */ diff --git a/xen/arch/x86/mm/Makefile b/xen/arch/x86/mm/Makefile index 960f6e8409..aa15811c2e 100644 --- a/xen/arch/x86/mm/Makefile +++ b/xen/arch/x86/mm/Makefile @@ -7,7 +7,7 @@ obj-$(CONFIG_SHADOW_PAGING) += guest_walk_4.o obj-$(CONFIG_VM_EVENT) += mem_access.o obj-$(CONFIG_MEM_PAGING) += mem_paging.o obj-$(CONFIG_MEM_SHARING) += mem_sharing.o -obj-$(CONFIG_HVM) += nested.o +obj-$(CONFIG_NESTED_VIRT) += nested.o obj-$(CONFIG_HVM) += p2m.o obj-y += p2m-basic.o obj-$(CONFIG_INTEL_VMX) += p2m-ept.o diff --git a/xen/arch/x86/mm/hap/Makefile b/xen/arch/x86/mm/hap/Makefile index 67c29b2162..efdc91ea82 100644 --- a/xen/arch/x86/mm/hap/Makefile +++ b/xen/arch/x86/mm/hap/Makefile @@ -2,5 +2,6 @@ obj-y += hap.o obj-y += guest_walk_2.o obj-y += guest_walk_3.o obj-y += guest_walk_4.o -obj-y += nested_hap.o -obj-$(CONFIG_INTEL_VMX) += nested_ept.o +nested-y := nested_hap.o +nested-$(CONFIG_INTEL_VMX) += nested_ept.o +obj-$(CONFIG_NESTED_VIRT) += $(nested-y) diff --git a/xen/arch/x86/mm/p2m.h b/xen/arch/x86/mm/p2m.h index 635f5a7f45..63808dddcc 100644 --- a/xen/arch/x86/mm/p2m.h +++ b/xen/arch/x86/mm/p2m.h @@ -25,9 +25,15 @@ void p2m_teardown_altp2m(struct domain *d); void p2m_flush_table_locked(struct p2m_domain *p2m); int __must_check p2m_remove_entry(struct p2m_domain *p2m, gfn_t gfn, mfn_t mfn, unsigned int page_order); +#ifdef CONFIG_NESTED_VIRT void p2m_nestedp2m_init(struct p2m_domain *p2m); int p2m_init_nestedp2m(struct domain *d); void p2m_teardown_nestedp2m(struct domain *d); +#else +static inline void p2m_nestedp2m_init(struct p2m_domain *p2m) { } +static inline int p2m_init_nestedp2m(struct domain *d) { return 0; } +static inline void p2m_teardown_nestedp2m(struct domain *d) { } +#endif int ept_p2m_init(struct p2m_domain *p2m); void ept_p2m_uninit(struct p2m_domain *p2m); diff --git a/xen/arch/x86/sysctl.c b/xen/arch/x86/sysctl.c index 1b04947516..b1d865e1c8 100644 --- a/xen/arch/x86/sysctl.c +++ b/xen/arch/x86/sysctl.c @@ -103,6 +103,8 @@ void arch_do_physinfo(struct xen_sysctl_physinfo *pi) pi->capabilities |= XEN_SYSCTL_PHYSCAP_hap; if ( IS_ENABLED(CONFIG_SHADOW_PAGING) ) pi->capabilities |= XEN_SYSCTL_PHYSCAP_shadow; + if ( hvm_nested_virt_supported() ) + pi->capabilities |= XEN_SYSCTL_PHYSCAP_nestedhvm; } long arch_do_sysctl( diff --git a/xen/include/public/sysctl.h b/xen/include/public/sysctl.h index 66c9b65465..b4bd1dd7b2 100644 --- a/xen/include/public/sysctl.h +++ b/xen/include/public/sysctl.h @@ -100,9 +100,11 @@ struct xen_sysctl_tbuf_op { /* Xen supports the Grant v1 and/or v2 ABIs. */ #define XEN_SYSCTL_PHYSCAP_gnttab_v1 (1u << 8) #define XEN_SYSCTL_PHYSCAP_gnttab_v2 (1u << 9) +/* The platform supports nested HVM. */ +#define XEN_SYSCTL_PHYSCAP_nestedhvm (1u << 10) /* Max XEN_SYSCTL_PHYSCAP_* constant. Used for ABI checking. */ -#define XEN_SYSCTL_PHYSCAP_MAX XEN_SYSCTL_PHYSCAP_gnttab_v2 +#define XEN_SYSCTL_PHYSCAP_MAX XEN_SYSCTL_PHYSCAP_nestedhvm #if defined(__arm__) || defined(__aarch64__) #define XEN_SYSCTL_PHYSCAP_ARM_SVE_MASK (0x1FU) -- 2.25.1
