x86/sev-es: Support CPU offline/online (094794f5) · Commits · 戴 / test

arch/x86/include/uapi/asm/svm.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -84,6 +84,7 @@
		/* SEV-ES software-defined VMGEXIT events */
		#define SVM_VMGEXIT_MMIO_READ 0x80000001
		#define SVM_VMGEXIT_MMIO_WRITE 0x80000002
		#define SVM_VMGEXIT_AP_HLT_LOOP 0x80000004
		#define SVM_VMGEXIT_AP_JUMP_TABLE 0x80000005
		#define SVM_VMGEXIT_SET_AP_JUMP_TABLE 0
		#define SVM_VMGEXIT_GET_AP_JUMP_TABLE 1

arch/x86/kernel/sev-es.c

+63 −0

Original line number	Diff line number	Diff line
		@@ -29,6 +29,8 @@
		#include <asm/realmode.h>
		#include <asm/traps.h>
		#include <asm/svm.h>
		#include <asm/smp.h>
		#include <asm/cpu.h>

		#define DR7_RESET_VALUE 0x400

		@@ -518,6 +520,65 @@ static bool __init sev_es_setup_ghcb(void)
		return true;
		}

		#ifdef CONFIG_HOTPLUG_CPU
		static void sev_es_ap_hlt_loop(void)
		{
		struct ghcb_state state;
		struct ghcb *ghcb;

		ghcb = sev_es_get_ghcb(&state);

		while (true) {
		vc_ghcb_invalidate(ghcb);
		ghcb_set_sw_exit_code(ghcb, SVM_VMGEXIT_AP_HLT_LOOP);
		ghcb_set_sw_exit_info_1(ghcb, 0);
		ghcb_set_sw_exit_info_2(ghcb, 0);

		sev_es_wr_ghcb_msr(__pa(ghcb));
		VMGEXIT();

		/* Wakeup signal? */
		if (ghcb_sw_exit_info_2_is_valid(ghcb) &&
		ghcb->save.sw_exit_info_2)
		break;
		}

		sev_es_put_ghcb(&state);
		}

		/*
		* Play_dead handler when running under SEV-ES. This is needed because
		* the hypervisor can't deliver an SIPI request to restart the AP.
		* Instead the kernel has to issue a VMGEXIT to halt the VCPU until the
		* hypervisor wakes it up again.
		*/
		static void sev_es_play_dead(void)
		{
		play_dead_common();

		/* IRQs now disabled */

		sev_es_ap_hlt_loop();

		/*
		* If we get here, the VCPU was woken up again. Jump to CPU
		* startup code to get it back online.
		*/
		start_cpu0();
		}
		#else /* CONFIG_HOTPLUG_CPU */
		#define sev_es_play_dead native_play_dead
		#endif /* CONFIG_HOTPLUG_CPU */

		#ifdef CONFIG_SMP
		static void __init sev_es_setup_play_dead(void)
		{
		smp_ops.play_dead = sev_es_play_dead;
		}
		#else
		static inline void sev_es_setup_play_dead(void) { }
		#endif

		static void __init alloc_runtime_data(int cpu)
		{
		struct sev_es_runtime_data *data;
		@@ -566,6 +627,8 @@ void __init sev_es_init_vc_handling(void)
		setup_vc_stacks(cpu);
		}

		sev_es_setup_play_dead();

		/* Secondary CPUs use the runtime #VC handler */
		initial_vc_handler = (unsigned long)safe_stack_exc_vmm_communication;
		}

Admin message