x86/paravirt: Allow hypervisor-specific VMMCALL handling under SEV-ES (f6a9f8a4) · Commits · 戴 / test

arch/x86/include/asm/x86_init.h

+15 −1

Original line number	Diff line number	Diff line
		@@ -4,8 +4,10 @@

		#include <asm/bootparam.h>

		struct ghcb;
		struct mpc_bus;
		struct mpc_cpu;
		struct pt_regs;
		struct mpc_table;
		struct cpuinfo_x86;

		@@ -236,10 +238,22 @@ struct x86_legacy_features {
		/**
		* struct x86_hyper_runtime - x86 hypervisor specific runtime callbacks
		*
		* @pin_vcpu: pin current vcpu to specified physical cpu (run rarely)
		* @pin_vcpu: pin current vcpu to specified physical
		* cpu (run rarely)
		* @sev_es_hcall_prepare: Load additional hypervisor-specific
		* state into the GHCB when doing a VMMCALL under
		* SEV-ES. Called from the #VC exception handler.
		* @sev_es_hcall_finish: Copies state from the GHCB back into the
		* processor (or pt_regs). Also runs checks on the
		* state returned from the hypervisor after a
		* VMMCALL under SEV-ES. Needs to return 'false'
		* if the checks fail. Called from the #VC
		* exception handler.
		*/
		struct x86_hyper_runtime {
		void (*pin_vcpu)(int cpu);
		void (sev_es_hcall_prepare)(struct ghcb ghcb, struct pt_regs *regs);
		bool (sev_es_hcall_finish)(struct ghcb ghcb, struct pt_regs *regs);
		};

		/**

+12 −0

Original line number	Diff line number	Diff line
		@@ -897,6 +897,9 @@ static enum es_result vc_handle_vmmcall(struct ghcb *ghcb,
		ghcb_set_rax(ghcb, ctxt->regs->ax);
		ghcb_set_cpl(ghcb, user_mode(ctxt->regs) ? 3 : 0);

		if (x86_platform.hyper.sev_es_hcall_prepare)
		x86_platform.hyper.sev_es_hcall_prepare(ghcb, ctxt->regs);

		ret = sev_es_ghcb_hv_call(ghcb, ctxt, SVM_EXIT_VMMCALL, 0, 0);
		if (ret != ES_OK)
		return ret;
		@@ -906,6 +909,15 @@ static enum es_result vc_handle_vmmcall(struct ghcb *ghcb,

		ctxt->regs->ax = ghcb->save.rax;

		/*
		* Call sev_es_hcall_finish() after regs->ax is already set.
		* This allows the hypervisor handler to overwrite it again if
		* necessary.
		*/
		if (x86_platform.hyper.sev_es_hcall_finish &&
		!x86_platform.hyper.sev_es_hcall_finish(ghcb, ctxt->regs))
		return ES_VMM_ERROR;

		return ES_OK;
		}