Merge tag 'kvm-riscv-6.9-1' of https://github.com/kvm-riscv/linux into HEAD

KVM/riscv changes for 6.9

- Exception and interrupt handling for selftests
- Sstc (aka arch_timer) selftest
- Forward seed CSR access to KVM userspace
- Ztso extension support for Guest/VM
- Zacas extension support for Guest/VM

arch/riscv/include/uapi/asm/kvm.h

@@ -165,6 +165,8 @@ enum KVM_RISCV_ISA_EXT_ID {
 	KVM_RISCV_ISA_EXT_ZVFH,
 	KVM_RISCV_ISA_EXT_ZVFHMIN,
 	KVM_RISCV_ISA_EXT_ZFA,
+	KVM_RISCV_ISA_EXT_ZTSO,
+	KVM_RISCV_ISA_EXT_ZACAS,
 	KVM_RISCV_ISA_EXT_MAX,
 };
 

arch/riscv/kvm/vcpu_insn.c

@@ -7,6 +7,8 @@
 #include <linux/bitops.h>
 #include <linux/kvm_host.h>
 
+#include <asm/cpufeature.h>
+
 #define INSN_OPCODE_MASK	0x007c
 #define INSN_OPCODE_SHIFT	2
 #define INSN_OPCODE_SYSTEM	28
@@ -213,9 +215,20 @@ struct csr_func {
 		    unsigned long wr_mask);
 };
 
+static int seed_csr_rmw(struct kvm_vcpu *vcpu, unsigned int csr_num,
+			unsigned long *val, unsigned long new_val,
+			unsigned long wr_mask)
+{
+	if (!riscv_isa_extension_available(vcpu->arch.isa, ZKR))
+		return KVM_INSN_ILLEGAL_TRAP;
+
+	return KVM_INSN_EXIT_TO_USER_SPACE;
+}
+
 static const struct csr_func csr_funcs[] = {
 	KVM_RISCV_VCPU_AIA_CSR_FUNCS
 	KVM_RISCV_VCPU_HPMCOUNTER_CSR_FUNCS
+	{ .base = CSR_SEED, .count = 1, .func = seed_csr_rmw },
 };
 
 /**

arch/riscv/kvm/vcpu_onereg.c

@@ -40,6 +40,7 @@ static const unsigned long kvm_isa_ext_arr[] = {
 	KVM_ISA_EXT_ARR(SVINVAL),
 	KVM_ISA_EXT_ARR(SVNAPOT),
 	KVM_ISA_EXT_ARR(SVPBMT),
+	KVM_ISA_EXT_ARR(ZACAS),
 	KVM_ISA_EXT_ARR(ZBA),
 	KVM_ISA_EXT_ARR(ZBB),
 	KVM_ISA_EXT_ARR(ZBC),
@@ -66,6 +67,7 @@ static const unsigned long kvm_isa_ext_arr[] = {
 	KVM_ISA_EXT_ARR(ZKSED),
 	KVM_ISA_EXT_ARR(ZKSH),
 	KVM_ISA_EXT_ARR(ZKT),
+	KVM_ISA_EXT_ARR(ZTSO),
 	KVM_ISA_EXT_ARR(ZVBB),
 	KVM_ISA_EXT_ARR(ZVBC),
 	KVM_ISA_EXT_ARR(ZVFH),
@@ -117,6 +119,7 @@ static bool kvm_riscv_vcpu_isa_disable_allowed(unsigned long ext)
 	case KVM_RISCV_ISA_EXT_SSTC:
 	case KVM_RISCV_ISA_EXT_SVINVAL:
 	case KVM_RISCV_ISA_EXT_SVNAPOT:
+	case KVM_RISCV_ISA_EXT_ZACAS:
 	case KVM_RISCV_ISA_EXT_ZBA:
 	case KVM_RISCV_ISA_EXT_ZBB:
 	case KVM_RISCV_ISA_EXT_ZBC:
@@ -141,6 +144,7 @@ static bool kvm_riscv_vcpu_isa_disable_allowed(unsigned long ext)
 	case KVM_RISCV_ISA_EXT_ZKSED:
 	case KVM_RISCV_ISA_EXT_ZKSH:
 	case KVM_RISCV_ISA_EXT_ZKT:
+	case KVM_RISCV_ISA_EXT_ZTSO:
 	case KVM_RISCV_ISA_EXT_ZVBB:
 	case KVM_RISCV_ISA_EXT_ZVBC:
 	case KVM_RISCV_ISA_EXT_ZVFH:

tools/arch/riscv/include/asm/vdso/processor.h

+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef __ASM_VDSO_PROCESSOR_H
+#define __ASM_VDSO_PROCESSOR_H
+
+#ifndef __ASSEMBLY__
+
+#include <asm-generic/barrier.h>
+
+static inline void cpu_relax(void)
+{
+#ifdef __riscv_muldiv
+	int dummy;
+	/* In lieu of a halt instruction, induce a long-latency stall. */
+	__asm__ __volatile__ ("div %0, %0, zero" : "=r" (dummy));
+#endif
+
+#ifdef CONFIG_TOOLCHAIN_HAS_ZIHINTPAUSE
+	/*
+	 * Reduce instruction retirement.
+	 * This assumes the PC changes.
+	 */
+	__asm__ __volatile__ ("pause");
+#else
+	/* Encoding of the pause instruction */
+	__asm__ __volatile__ (".4byte 0x100000F");
+#endif
+	barrier();
+}
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* __ASM_VDSO_PROCESSOR_H */

tools/testing/selftests/kvm/Makefile

@@ -53,6 +53,7 @@ LIBKVM_s390x += lib/s390x/diag318_test_handler.c
 LIBKVM_s390x += lib/s390x/processor.c
 LIBKVM_s390x += lib/s390x/ucall.c
 
+LIBKVM_riscv += lib/riscv/handlers.S
 LIBKVM_riscv += lib/riscv/processor.c
 LIBKVM_riscv += lib/riscv/ucall.c
 
@@ -143,7 +144,6 @@ TEST_GEN_PROGS_x86_64 += system_counter_offset_test
 TEST_GEN_PROGS_EXTENDED_x86_64 += x86_64/nx_huge_pages_test
 
 TEST_GEN_PROGS_aarch64 += aarch64/aarch32_id_regs
-TEST_GEN_PROGS_aarch64 += aarch64/arch_timer
 TEST_GEN_PROGS_aarch64 += aarch64/debug-exceptions
 TEST_GEN_PROGS_aarch64 += aarch64/hypercalls
 TEST_GEN_PROGS_aarch64 += aarch64/page_fault_test
@@ -155,6 +155,7 @@ TEST_GEN_PROGS_aarch64 += aarch64/vgic_init
 TEST_GEN_PROGS_aarch64 += aarch64/vgic_irq
 TEST_GEN_PROGS_aarch64 += aarch64/vpmu_counter_access
 TEST_GEN_PROGS_aarch64 += access_tracking_perf_test
+TEST_GEN_PROGS_aarch64 += arch_timer
 TEST_GEN_PROGS_aarch64 += demand_paging_test
 TEST_GEN_PROGS_aarch64 += dirty_log_test
 TEST_GEN_PROGS_aarch64 += dirty_log_perf_test
@@ -184,6 +185,7 @@ TEST_GEN_PROGS_s390x += rseq_test
 TEST_GEN_PROGS_s390x += set_memory_region_test
 TEST_GEN_PROGS_s390x += kvm_binary_stats_test
 
+TEST_GEN_PROGS_riscv += arch_timer
 TEST_GEN_PROGS_riscv += demand_paging_test
 TEST_GEN_PROGS_riscv += dirty_log_test
 TEST_GEN_PROGS_riscv += get-reg-list
@@ -194,6 +196,7 @@ TEST_GEN_PROGS_riscv += kvm_page_table_test
 TEST_GEN_PROGS_riscv += set_memory_region_test
 TEST_GEN_PROGS_riscv += steal_time
 
+SPLIT_TESTS += arch_timer
 SPLIT_TESTS += get-reg-list
 
 TEST_PROGS += $(TEST_PROGS_$(ARCH_DIR))
@@ -217,7 +220,7 @@ else
 LINUX_TOOL_ARCH_INCLUDE = $(top_srcdir)/tools/arch/$(ARCH)/include
 endif
 CFLAGS += -Wall -Wstrict-prototypes -Wuninitialized -O2 -g -std=gnu99 \
-	-Wno-gnu-variable-sized-type-not-at-end -MD -MP \
+	-Wno-gnu-variable-sized-type-not-at-end -MD -MP -DCONFIG_64BIT \
 	-fno-builtin-memcmp -fno-builtin-memcpy -fno-builtin-memset \
 	-fno-builtin-strnlen \
 	-fno-stack-protector -fno-PIE -I$(LINUX_TOOL_INCLUDE) \
@@ -260,32 +263,36 @@ LIBKVM_C_OBJ := $(patsubst %.c, $(OUTPUT)/%.o, $(LIBKVM_C))
 LIBKVM_S_OBJ := $(patsubst %.S, $(OUTPUT)/%.o, $(LIBKVM_S))
 LIBKVM_STRING_OBJ := $(patsubst %.c, $(OUTPUT)/%.o, $(LIBKVM_STRING))
 LIBKVM_OBJS = $(LIBKVM_C_OBJ) $(LIBKVM_S_OBJ) $(LIBKVM_STRING_OBJ)
-SPLIT_TESTS_TARGETS := $(patsubst %, $(OUTPUT)/%, $(SPLIT_TESTS))
-SPLIT_TESTS_OBJS := $(patsubst %, $(ARCH_DIR)/%.o, $(SPLIT_TESTS))
+SPLIT_TEST_GEN_PROGS := $(patsubst %, $(OUTPUT)/%, $(SPLIT_TESTS))
+SPLIT_TEST_GEN_OBJ := $(patsubst %, $(OUTPUT)/$(ARCH_DIR)/%.o, $(SPLIT_TESTS))
 
 TEST_GEN_OBJ = $(patsubst %, %.o, $(TEST_GEN_PROGS))
 TEST_GEN_OBJ += $(patsubst %, %.o, $(TEST_GEN_PROGS_EXTENDED))
 TEST_DEP_FILES = $(patsubst %.o, %.d, $(TEST_GEN_OBJ))
 TEST_DEP_FILES += $(patsubst %.o, %.d, $(LIBKVM_OBJS))
-TEST_DEP_FILES += $(patsubst %.o, %.d, $(SPLIT_TESTS_OBJS))
+TEST_DEP_FILES += $(patsubst %.o, %.d, $(SPLIT_TEST_GEN_OBJ))
 -include $(TEST_DEP_FILES)
 
-$(TEST_GEN_PROGS) $(TEST_GEN_PROGS_EXTENDED): %: %.o
+x := $(shell mkdir -p $(sort $(OUTPUT)/$(ARCH_DIR) $(dir $(LIBKVM_C_OBJ) $(LIBKVM_S_OBJ))))
+
+$(filter-out $(SPLIT_TEST_GEN_PROGS), $(TEST_GEN_PROGS)) \
+$(TEST_GEN_PROGS_EXTENDED): %: %.o
 	$(CC) $(CFLAGS) $(CPPFLAGS) $(LDFLAGS) $(TARGET_ARCH) $< $(LIBKVM_OBJS) $(LDLIBS) -o $@
 $(TEST_GEN_OBJ): $(OUTPUT)/%.o: %.c
 	$(CC) $(CFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c $< -o $@
 
-$(SPLIT_TESTS_TARGETS): %: %.o $(SPLIT_TESTS_OBJS)
+$(SPLIT_TEST_GEN_PROGS): $(OUTPUT)/%: $(OUTPUT)/%.o $(OUTPUT)/$(ARCH_DIR)/%.o
 	$(CC) $(CFLAGS) $(CPPFLAGS) $(LDFLAGS) $(TARGET_ARCH) $^ $(LDLIBS) -o $@
+$(SPLIT_TEST_GEN_OBJ): $(OUTPUT)/$(ARCH_DIR)/%.o: $(ARCH_DIR)/%.c
+	$(CC) $(CFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c $< -o $@
 
 EXTRA_CLEAN += $(GEN_HDRS) \
 	       $(LIBKVM_OBJS) \
-	       $(SPLIT_TESTS_OBJS) \
+	       $(SPLIT_TEST_GEN_OBJ) \
 	       $(TEST_DEP_FILES) \
 	       $(TEST_GEN_OBJ) \
 	       cscope.*
 
-x := $(shell mkdir -p $(sort $(dir $(LIBKVM_C_OBJ) $(LIBKVM_S_OBJ))))
 $(LIBKVM_C_OBJ): $(OUTPUT)/%.o: %.c $(GEN_HDRS)
 	$(CC) $(CFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c $< -o $@
 
@@ -299,7 +306,7 @@ $(LIBKVM_STRING_OBJ): $(OUTPUT)/%.o: %.c
 	$(CC) $(CFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c -ffreestanding $< -o $@
 
 x := $(shell mkdir -p $(sort $(dir $(TEST_GEN_PROGS))))
-$(SPLIT_TESTS_OBJS): $(GEN_HDRS)
+$(SPLIT_TEST_GEN_OBJ): $(GEN_HDRS)
 $(TEST_GEN_PROGS): $(LIBKVM_OBJS)
 $(TEST_GEN_PROGS_EXTENDED): $(LIBKVM_OBJS)
 $(TEST_GEN_OBJ): $(GEN_HDRS)

tools/testing/selftests/kvm/aarch64/arch_timer.c

 // SPDX-License-Identifier: GPL-2.0-only
 /*
- * arch_timer.c - Tests the aarch64 timer IRQ functionality
- *
  * The test validates both the virtual and physical timer IRQs using
- * CVAL and TVAL registers. This consitutes the four stages in the test.
- * The guest's main thread configures the timer interrupt for a stage
- * and waits for it to fire, with a timeout equal to the timer period.
- * It asserts that the timeout doesn't exceed the timer period.
- *
- * On the other hand, upon receipt of an interrupt, the guest's interrupt
- * handler validates the interrupt by checking if the architectural state
- * is in compliance with the specifications.
- *
- * The test provides command-line options to configure the timer's
- * period (-p), number of vCPUs (-n), and iterations per stage (-i).
- * To stress-test the timer stack even more, an option to migrate the
- * vCPUs across pCPUs (-m), at a particular rate, is also provided.
+ * CVAL and TVAL registers.
  *
  * Copyright (c) 2021, Google LLC.
  */
 #define _GNU_SOURCE
 
-#include <stdlib.h>
-#include <pthread.h>
-#include <linux/kvm.h>
-#include <linux/sizes.h>
-#include <linux/bitmap.h>
-#include <sys/sysinfo.h>
-
-#include "kvm_util.h"
-#include "processor.h"
-#include "delay.h"
 #include "arch_timer.h"
+#include "delay.h"
 #include "gic.h"
+#include "processor.h"
+#include "timer_test.h"
 #include "vgic.h"
 
-#define NR_VCPUS_DEF			4
-#define NR_TEST_ITERS_DEF		5
-#define TIMER_TEST_PERIOD_MS_DEF	10
-#define TIMER_TEST_ERR_MARGIN_US	100
-#define TIMER_TEST_MIGRATION_FREQ_MS	2
-
-struct test_args {
-	int nr_vcpus;
-	int nr_iter;
-	int timer_period_ms;
-	int migration_freq_ms;
-	struct kvm_arm_counter_offset offset;
-};
-
-static struct test_args test_args = {
-	.nr_vcpus = NR_VCPUS_DEF,
-	.nr_iter = NR_TEST_ITERS_DEF,
-	.timer_period_ms = TIMER_TEST_PERIOD_MS_DEF,
-	.migration_freq_ms = TIMER_TEST_MIGRATION_FREQ_MS,
-	.offset = { .reserved = 1 },
-};
-
-#define msecs_to_usecs(msec)		((msec) * 1000LL)
-
 #define GICD_BASE_GPA			0x8000000ULL
 #define GICR_BASE_GPA			0x80A0000ULL
 
@@ -70,22 +25,8 @@ enum guest_stage {
 	GUEST_STAGE_MAX,
 };
 
-/* Shared variables between host and guest */
-struct test_vcpu_shared_data {
-	int nr_iter;
-	enum guest_stage guest_stage;
-	uint64_t xcnt;
-};
-
-static struct kvm_vcpu *vcpus[KVM_MAX_VCPUS];
-static pthread_t pt_vcpu_run[KVM_MAX_VCPUS];
-static struct test_vcpu_shared_data vcpu_shared_data[KVM_MAX_VCPUS];
-
 static int vtimer_irq, ptimer_irq;
 
-static unsigned long *vcpu_done_map;
-static pthread_mutex_t vcpu_done_map_lock;
-
 static void
 guest_configure_timer_action(struct test_vcpu_shared_data *shared_data)
 {
@@ -190,10 +131,14 @@ static void guest_run_stage(struct test_vcpu_shared_data *shared_data,
 
 		/* Setup a timeout for the interrupt to arrive */
 		udelay(msecs_to_usecs(test_args.timer_period_ms) +
-			TIMER_TEST_ERR_MARGIN_US);
+			test_args.timer_err_margin_us);
 
 		irq_iter = READ_ONCE(shared_data->nr_iter);
-		GUEST_ASSERT_EQ(config_iter + 1, irq_iter);
+		__GUEST_ASSERT(config_iter + 1 == irq_iter,
+				"config_iter + 1 = 0x%lx, irq_iter = 0x%lx.\n"
+				"  Guest timer interrupt was not trigged within the specified\n"
+				"  interval, try to increase the error margin by [-e] option.\n",
+				config_iter + 1, irq_iter);
 	}
 }
 
@@ -222,137 +167,6 @@ static void guest_code(void)
 	GUEST_DONE();
 }
 
-static void *test_vcpu_run(void *arg)
-{
-	unsigned int vcpu_idx = (unsigned long)arg;
-	struct ucall uc;
-	struct kvm_vcpu *vcpu = vcpus[vcpu_idx];
-	struct kvm_vm *vm = vcpu->vm;
-	struct test_vcpu_shared_data *shared_data = &vcpu_shared_data[vcpu_idx];
-
-	vcpu_run(vcpu);
-
-	/* Currently, any exit from guest is an indication of completion */
-	pthread_mutex_lock(&vcpu_done_map_lock);
-	__set_bit(vcpu_idx, vcpu_done_map);
-	pthread_mutex_unlock(&vcpu_done_map_lock);
-
-	switch (get_ucall(vcpu, &uc)) {
-	case UCALL_SYNC:
-	case UCALL_DONE:
-		break;
-	case UCALL_ABORT:
-		sync_global_from_guest(vm, *shared_data);
-		fprintf(stderr, "Guest assert failed,  vcpu %u; stage; %u; iter: %u\n",
-			vcpu_idx, shared_data->guest_stage, shared_data->nr_iter);
-		REPORT_GUEST_ASSERT(uc);
-		break;
-	default:
-		TEST_FAIL("Unexpected guest exit");
-	}
-
-	return NULL;
-}
-
-static uint32_t test_get_pcpu(void)
-{
-	uint32_t pcpu;
-	unsigned int nproc_conf;
-	cpu_set_t online_cpuset;
-
-	nproc_conf = get_nprocs_conf();
-	sched_getaffinity(0, sizeof(cpu_set_t), &online_cpuset);
-
-	/* Randomly find an available pCPU to place a vCPU on */
-	do {
-		pcpu = rand() % nproc_conf;
-	} while (!CPU_ISSET(pcpu, &online_cpuset));
-
-	return pcpu;
-}
-
-static int test_migrate_vcpu(unsigned int vcpu_idx)
-{
-	int ret;
-	cpu_set_t cpuset;
-	uint32_t new_pcpu = test_get_pcpu();
-
-	CPU_ZERO(&cpuset);
-	CPU_SET(new_pcpu, &cpuset);
-
-	pr_debug("Migrating vCPU: %u to pCPU: %u\n", vcpu_idx, new_pcpu);
-
-	ret = pthread_setaffinity_np(pt_vcpu_run[vcpu_idx],
-				     sizeof(cpuset), &cpuset);
-
-	/* Allow the error where the vCPU thread is already finished */
-	TEST_ASSERT(ret == 0 || ret == ESRCH,
-		    "Failed to migrate the vCPU:%u to pCPU: %u; ret: %d",
-		    vcpu_idx, new_pcpu, ret);
-
-	return ret;
-}
-
-static void *test_vcpu_migration(void *arg)
-{
-	unsigned int i, n_done;
-	bool vcpu_done;
-
-	do {
-		usleep(msecs_to_usecs(test_args.migration_freq_ms));
-
-		for (n_done = 0, i = 0; i < test_args.nr_vcpus; i++) {
-			pthread_mutex_lock(&vcpu_done_map_lock);
-			vcpu_done = test_bit(i, vcpu_done_map);
-			pthread_mutex_unlock(&vcpu_done_map_lock);
-
-			if (vcpu_done) {
-				n_done++;
-				continue;
-			}
-
-			test_migrate_vcpu(i);
-		}
-	} while (test_args.nr_vcpus != n_done);
-
-	return NULL;
-}
-
-static void test_run(struct kvm_vm *vm)
-{
-	pthread_t pt_vcpu_migration;
-	unsigned int i;
-	int ret;
-
-	pthread_mutex_init(&vcpu_done_map_lock, NULL);
-	vcpu_done_map = bitmap_zalloc(test_args.nr_vcpus);
-	TEST_ASSERT(vcpu_done_map, "Failed to allocate vcpu done bitmap");
-
-	for (i = 0; i < (unsigned long)test_args.nr_vcpus; i++) {
-		ret = pthread_create(&pt_vcpu_run[i], NULL, test_vcpu_run,
-				     (void *)(unsigned long)i);
-		TEST_ASSERT(!ret, "Failed to create vCPU-%d pthread", i);
-	}
-
-	/* Spawn a thread to control the vCPU migrations */
-	if (test_args.migration_freq_ms) {
-		srand(time(NULL));
-
-		ret = pthread_create(&pt_vcpu_migration, NULL,
-					test_vcpu_migration, NULL);
-		TEST_ASSERT(!ret, "Failed to create the migration pthread");
-	}
-
-
-	for (i = 0; i < test_args.nr_vcpus; i++)
-		pthread_join(pt_vcpu_run[i], NULL);
-
-	if (test_args.migration_freq_ms)
-		pthread_join(pt_vcpu_migration, NULL);
-
-	bitmap_free(vcpu_done_map);
-}
-
 static void test_init_timer_irq(struct kvm_vm *vm)
 {
 	/* Timer initid should be same for all the vCPUs, so query only vCPU-0 */
@@ -369,7 +183,7 @@ static void test_init_timer_irq(struct kvm_vm *vm)
 
 static int gic_fd;
 
-static struct kvm_vm *test_vm_create(void)
+struct kvm_vm *test_vm_create(void)
 {
 	struct kvm_vm *vm;
 	unsigned int i;
@@ -380,10 +194,14 @@ static struct kvm_vm *test_vm_create(void)
 	vm_init_descriptor_tables(vm);
 	vm_install_exception_handler(vm, VECTOR_IRQ_CURRENT, guest_irq_handler);
 
-	if (!test_args.offset.reserved) {
-		if (kvm_has_cap(KVM_CAP_COUNTER_OFFSET))
-			vm_ioctl(vm, KVM_ARM_SET_COUNTER_OFFSET, &test_args.offset);
-		else
+	if (!test_args.reserved) {
+		if (kvm_has_cap(KVM_CAP_COUNTER_OFFSET)) {
+			struct kvm_arm_counter_offset offset = {
+				.counter_offset = test_args.counter_offset,
+				.reserved = 0,
+			};
+			vm_ioctl(vm, KVM_ARM_SET_COUNTER_OFFSET, &offset);
+		} else
 			TEST_FAIL("no support for global offset");
 	}
 
@@ -400,81 +218,8 @@ static struct kvm_vm *test_vm_create(void)
 	return vm;
 }
 
-static void test_vm_cleanup(struct kvm_vm *vm)
+void test_vm_cleanup(struct kvm_vm *vm)
 {
 	close(gic_fd);
 	kvm_vm_free(vm);
 }
-
-static void test_print_help(char *name)
-{
-	pr_info("Usage: %s [-h] [-n nr_vcpus] [-i iterations] [-p timer_period_ms]\n",
-		name);
-	pr_info("\t-n: Number of vCPUs to configure (default: %u; max: %u)\n",
-		NR_VCPUS_DEF, KVM_MAX_VCPUS);
-	pr_info("\t-i: Number of iterations per stage (default: %u)\n",
-		NR_TEST_ITERS_DEF);
-	pr_info("\t-p: Periodicity (in ms) of the guest timer (default: %u)\n",
-		TIMER_TEST_PERIOD_MS_DEF);
-	pr_info("\t-m: Frequency (in ms) of vCPUs to migrate to different pCPU. 0 to turn off (default: %u)\n",
-		TIMER_TEST_MIGRATION_FREQ_MS);
-	pr_info("\t-o: Counter offset (in counter cycles, default: 0)\n");
-	pr_info("\t-h: print this help screen\n");
-}
-
-static bool parse_args(int argc, char *argv[])
-{
-	int opt;
-
-	while ((opt = getopt(argc, argv, "hn:i:p:m:o:")) != -1) {
-		switch (opt) {
-		case 'n':
-			test_args.nr_vcpus = atoi_positive("Number of vCPUs", optarg);
-			if (test_args.nr_vcpus > KVM_MAX_VCPUS) {
-				pr_info("Max allowed vCPUs: %u\n",
-					KVM_MAX_VCPUS);
-				goto err;
-			}
-			break;
-		case 'i':
-			test_args.nr_iter = atoi_positive("Number of iterations", optarg);
-			break;
-		case 'p':
-			test_args.timer_period_ms = atoi_positive("Periodicity", optarg);
-			break;
-		case 'm':
-			test_args.migration_freq_ms = atoi_non_negative("Frequency", optarg);
-			break;
-		case 'o':
-			test_args.offset.counter_offset = strtol(optarg, NULL, 0);
-			test_args.offset.reserved = 0;
-			break;
-		case 'h':
-		default:
-			goto err;
-		}
-	}
-
-	return true;
-
-err:
-	test_print_help(argv[0]);
-	return false;
-}
-
-int main(int argc, char *argv[])
-{
-	struct kvm_vm *vm;
-
-	if (!parse_args(argc, argv))
-		exit(KSFT_SKIP);
-
-	__TEST_REQUIRE(!test_args.migration_freq_ms || get_nprocs() >= 2,
-		       "At least two physical CPUs needed for vCPU migration");
-
-	vm = test_vm_create();
-	test_run(vm);
-	test_vm_cleanup(vm);
-
-	return 0;
-}

tools/testing/selftests/kvm/arch_timer.c

+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * arch_timer.c - Tests the arch timer IRQ functionality
+ *
+ * The guest's main thread configures the timer interrupt and waits
+ * for it to fire, with a timeout equal to the timer period.
+ * It asserts that the timeout doesn't exceed the timer period plus
+ * a user configurable error margin(default to 100us)
+ *
+ * On the other hand, upon receipt of an interrupt, the guest's interrupt
+ * handler validates the interrupt by checking if the architectural state
+ * is in compliance with the specifications.
+ *
+ * The test provides command-line options to configure the timer's
+ * period (-p), number of vCPUs (-n), iterations per stage (-i) and timer
+ * interrupt arrival error margin (-e). To stress-test the timer stack
+ * even more, an option to migrate the vCPUs across pCPUs (-m), at a
+ * particular rate, is also provided.
+ *
+ * Copyright (c) 2021, Google LLC.
+ */
+
+#define _GNU_SOURCE
+
+#include <stdlib.h>
+#include <pthread.h>
+#include <linux/sizes.h>
+#include <linux/bitmap.h>
+#include <sys/sysinfo.h>
+
+#include "timer_test.h"
+
+struct test_args test_args = {
+	.nr_vcpus = NR_VCPUS_DEF,
+	.nr_iter = NR_TEST_ITERS_DEF,
+	.timer_period_ms = TIMER_TEST_PERIOD_MS_DEF,
+	.migration_freq_ms = TIMER_TEST_MIGRATION_FREQ_MS,
+	.timer_err_margin_us = TIMER_TEST_ERR_MARGIN_US,
+	.reserved = 1,
+};
+
+struct kvm_vcpu *vcpus[KVM_MAX_VCPUS];
+struct test_vcpu_shared_data vcpu_shared_data[KVM_MAX_VCPUS];
+
+static pthread_t pt_vcpu_run[KVM_MAX_VCPUS];
+static unsigned long *vcpu_done_map;
+static pthread_mutex_t vcpu_done_map_lock;
+
+static void *test_vcpu_run(void *arg)
+{
+	unsigned int vcpu_idx = (unsigned long)arg;
+	struct ucall uc;
+	struct kvm_vcpu *vcpu = vcpus[vcpu_idx];
+	struct kvm_vm *vm = vcpu->vm;
+	struct test_vcpu_shared_data *shared_data = &vcpu_shared_data[vcpu_idx];
+
+	vcpu_run(vcpu);
+
+	/* Currently, any exit from guest is an indication of completion */
+	pthread_mutex_lock(&vcpu_done_map_lock);
+	__set_bit(vcpu_idx, vcpu_done_map);
+	pthread_mutex_unlock(&vcpu_done_map_lock);
+
+	switch (get_ucall(vcpu, &uc)) {
+	case UCALL_SYNC:
+	case UCALL_DONE:
+		break;
+	case UCALL_ABORT:
+		sync_global_from_guest(vm, *shared_data);
+		fprintf(stderr, "Guest assert failed,  vcpu %u; stage; %u; iter: %u\n",
+			vcpu_idx, shared_data->guest_stage, shared_data->nr_iter);
+		REPORT_GUEST_ASSERT(uc);
+		break;
+	default:
+		TEST_FAIL("Unexpected guest exit");
+	}
+
+	pr_info("PASS(vCPU-%d).\n", vcpu_idx);
+
+	return NULL;
+}
+
+static uint32_t test_get_pcpu(void)
+{
+	uint32_t pcpu;
+	unsigned int nproc_conf;
+	cpu_set_t online_cpuset;
+
+	nproc_conf = get_nprocs_conf();
+	sched_getaffinity(0, sizeof(cpu_set_t), &online_cpuset);
+
+	/* Randomly find an available pCPU to place a vCPU on */
+	do {
+		pcpu = rand() % nproc_conf;
+	} while (!CPU_ISSET(pcpu, &online_cpuset));
+
+	return pcpu;
+}
+
+static int test_migrate_vcpu(unsigned int vcpu_idx)
+{
+	int ret;
+	cpu_set_t cpuset;
+	uint32_t new_pcpu = test_get_pcpu();
+
+	CPU_ZERO(&cpuset);
+	CPU_SET(new_pcpu, &cpuset);
+
+	pr_debug("Migrating vCPU: %u to pCPU: %u\n", vcpu_idx, new_pcpu);
+
+	ret = pthread_setaffinity_np(pt_vcpu_run[vcpu_idx],
+				     sizeof(cpuset), &cpuset);
+
+	/* Allow the error where the vCPU thread is already finished */
+	TEST_ASSERT(ret == 0 || ret == ESRCH,
+		    "Failed to migrate the vCPU:%u to pCPU: %u; ret: %d",
+		    vcpu_idx, new_pcpu, ret);
+
+	return ret;
+}
+
+static void *test_vcpu_migration(void *arg)
+{
+	unsigned int i, n_done;
+	bool vcpu_done;
+
+	do {
+		usleep(msecs_to_usecs(test_args.migration_freq_ms));
+
+		for (n_done = 0, i = 0; i < test_args.nr_vcpus; i++) {
+			pthread_mutex_lock(&vcpu_done_map_lock);
+			vcpu_done = test_bit(i, vcpu_done_map);
+			pthread_mutex_unlock(&vcpu_done_map_lock);
+
+			if (vcpu_done) {
+				n_done++;
+				continue;
+			}
+
+			test_migrate_vcpu(i);
+		}
+	} while (test_args.nr_vcpus != n_done);
+
+	return NULL;
+}
+
+static void test_run(struct kvm_vm *vm)
+{
+	pthread_t pt_vcpu_migration;
+	unsigned int i;
+	int ret;
+
+	pthread_mutex_init(&vcpu_done_map_lock, NULL);
+	vcpu_done_map = bitmap_zalloc(test_args.nr_vcpus);
+	TEST_ASSERT(vcpu_done_map, "Failed to allocate vcpu done bitmap");
+
+	for (i = 0; i < (unsigned long)test_args.nr_vcpus; i++) {
+		ret = pthread_create(&pt_vcpu_run[i], NULL, test_vcpu_run,
+				     (void *)(unsigned long)i);
+		TEST_ASSERT(!ret, "Failed to create vCPU-%d pthread", i);
+	}
+
+	/* Spawn a thread to control the vCPU migrations */
+	if (test_args.migration_freq_ms) {
+		srand(time(NULL));
+
+		ret = pthread_create(&pt_vcpu_migration, NULL,
+					test_vcpu_migration, NULL);
+		TEST_ASSERT(!ret, "Failed to create the migration pthread");
+	}
+
+
+	for (i = 0; i < test_args.nr_vcpus; i++)
+		pthread_join(pt_vcpu_run[i], NULL);
+
+	if (test_args.migration_freq_ms)
+		pthread_join(pt_vcpu_migration, NULL);
+
+	bitmap_free(vcpu_done_map);
+}
+
+static void test_print_help(char *name)
+{
+	pr_info("Usage: %s [-h] [-n nr_vcpus] [-i iterations] [-p timer_period_ms]\n"
+		"\t\t    [-m migration_freq_ms] [-o counter_offset]\n"
+		"\t\t    [-e timer_err_margin_us]\n", name);
+	pr_info("\t-n: Number of vCPUs to configure (default: %u; max: %u)\n",
+		NR_VCPUS_DEF, KVM_MAX_VCPUS);
+	pr_info("\t-i: Number of iterations per stage (default: %u)\n",
+		NR_TEST_ITERS_DEF);
+	pr_info("\t-p: Periodicity (in ms) of the guest timer (default: %u)\n",
+		TIMER_TEST_PERIOD_MS_DEF);
+	pr_info("\t-m: Frequency (in ms) of vCPUs to migrate to different pCPU. 0 to turn off (default: %u)\n",
+		TIMER_TEST_MIGRATION_FREQ_MS);
+	pr_info("\t-o: Counter offset (in counter cycles, default: 0) [aarch64-only]\n");
+	pr_info("\t-e: Interrupt arrival error margin (in us) of the guest timer (default: %u)\n",
+		TIMER_TEST_ERR_MARGIN_US);
+	pr_info("\t-h: print this help screen\n");
+}
+
+static bool parse_args(int argc, char *argv[])
+{
+	int opt;
+
+	while ((opt = getopt(argc, argv, "hn:i:p:m:o:e:")) != -1) {
+		switch (opt) {
+		case 'n':
+			test_args.nr_vcpus = atoi_positive("Number of vCPUs", optarg);
+			if (test_args.nr_vcpus > KVM_MAX_VCPUS) {
+				pr_info("Max allowed vCPUs: %u\n",
+					KVM_MAX_VCPUS);
+				goto err;
+			}
+			break;
+		case 'i':
+			test_args.nr_iter = atoi_positive("Number of iterations", optarg);
+			break;
+		case 'p':
+			test_args.timer_period_ms = atoi_positive("Periodicity", optarg);
+			break;
+		case 'm':
+			test_args.migration_freq_ms = atoi_non_negative("Frequency", optarg);
+			break;
+		case 'e':
+			test_args.timer_err_margin_us = atoi_non_negative("Error Margin", optarg);
+			break;
+		case 'o':
+			test_args.counter_offset = strtol(optarg, NULL, 0);
+			test_args.reserved = 0;
+			break;
+		case 'h':
+		default:
+			goto err;
+		}
+	}
+
+	return true;
+
+err:
+	test_print_help(argv[0]);
+	return false;
+}
+
+int main(int argc, char *argv[])
+{
+	struct kvm_vm *vm;
+
+	if (!parse_args(argc, argv))
+		exit(KSFT_SKIP);
+
+	__TEST_REQUIRE(!test_args.migration_freq_ms || get_nprocs() >= 2,
+		       "At least two physical CPUs needed for vCPU migration");
+
+	vm = test_vm_create();
+	test_run(vm);
+	test_vm_cleanup(vm);
+
+	return 0;
+}

tools/testing/selftests/kvm/include/aarch64/processor.h

@@ -226,8 +226,4 @@ void smccc_smc(uint32_t function_id, uint64_t arg0, uint64_t arg1,
 	       uint64_t arg2, uint64_t arg3, uint64_t arg4, uint64_t arg5,
 	       uint64_t arg6, struct arm_smccc_res *res);
 
-
-
-uint32_t guest_get_vcpuid(void);
-
 #endif /* SELFTEST_KVM_PROCESSOR_H */

tools/testing/selftests/kvm/include/kvm_util_base.h

@@ -1081,4 +1081,6 @@ void kvm_selftest_arch_init(void);
 
 void kvm_arch_vm_post_create(struct kvm_vm *vm);
 
+uint32_t guest_get_vcpuid(void);
+
 #endif /* SELFTEST_KVM_UTIL_BASE_H */

tools/testing/selftests/kvm/include/riscv/arch_timer.h

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * RISC-V Arch Timer(sstc) specific interface
+ *
+ * Copyright (c) 2024 Intel Corporation
+ */
+
+#ifndef SELFTEST_KVM_ARCH_TIMER_H
+#define SELFTEST_KVM_ARCH_TIMER_H
+
+#include <asm/csr.h>
+#include <asm/vdso/processor.h>
+
+static unsigned long timer_freq;
+
+#define msec_to_cycles(msec)	\
+	((timer_freq) * (uint64_t)(msec) / 1000)
+
+#define usec_to_cycles(usec)	\
+	((timer_freq) * (uint64_t)(usec) / 1000000)
+
+#define cycles_to_usec(cycles) \
+	((uint64_t)(cycles) * 1000000 / (timer_freq))
+
+static inline uint64_t timer_get_cycles(void)
+{
+	return csr_read(CSR_TIME);
+}
+
+static inline void timer_set_cmp(uint64_t cval)
+{
+	csr_write(CSR_STIMECMP, cval);
+}
+
+static inline uint64_t timer_get_cmp(void)
+{
+	return csr_read(CSR_STIMECMP);
+}
+
+static inline void timer_irq_enable(void)
+{
+	csr_set(CSR_SIE, IE_TIE);
+}
+
+static inline void timer_irq_disable(void)
+{
+	csr_clear(CSR_SIE, IE_TIE);
+}
+
+static inline void timer_set_next_cmp_ms(uint32_t msec)
+{
+	uint64_t now_ct = timer_get_cycles();
+	uint64_t next_ct = now_ct + msec_to_cycles(msec);
+
+	timer_set_cmp(next_ct);
+}
+
+static inline void __delay(uint64_t cycles)
+{
+	uint64_t start = timer_get_cycles();
+
+	while ((timer_get_cycles() - start) < cycles)
+		cpu_relax();
+}
+
+static inline void udelay(unsigned long usec)
+{
+	__delay(usec_to_cycles(usec));
+}
+
+#endif /* SELFTEST_KVM_ARCH_TIMER_H */

tools/testing/selftests/kvm/include/riscv/processor.h

@@ -7,8 +7,9 @@
 #ifndef SELFTEST_KVM_PROCESSOR_H
 #define SELFTEST_KVM_PROCESSOR_H
 
-#include "kvm_util.h"
 #include <linux/stringify.h>
+#include <asm/csr.h>
+#include "kvm_util.h"
 
 static inline uint64_t __kvm_reg_id(uint64_t type, uint64_t subtype,
 				    uint64_t idx, uint64_t size)
@@ -47,6 +48,58 @@ static inline uint64_t __kvm_reg_id(uint64_t type, uint64_t subtype,
 						     KVM_REG_RISCV_SBI_SINGLE,		\
 						     idx, KVM_REG_SIZE_ULONG)
 
+bool __vcpu_has_ext(struct kvm_vcpu *vcpu, uint64_t ext);
+
+struct ex_regs {
+	unsigned long ra;
+	unsigned long sp;
+	unsigned long gp;
+	unsigned long tp;
+	unsigned long t0;
+	unsigned long t1;
+	unsigned long t2;
+	unsigned long s0;
+	unsigned long s1;
+	unsigned long a0;
+	unsigned long a1;
+	unsigned long a2;
+	unsigned long a3;
+	unsigned long a4;
+	unsigned long a5;
+	unsigned long a6;
+	unsigned long a7;
+	unsigned long s2;
+	unsigned long s3;
+	unsigned long s4;
+	unsigned long s5;
+	unsigned long s6;
+	unsigned long s7;
+	unsigned long s8;
+	unsigned long s9;
+	unsigned long s10;
+	unsigned long s11;
+	unsigned long t3;
+	unsigned long t4;
+	unsigned long t5;
+	unsigned long t6;
+	unsigned long epc;
+	unsigned long status;
+	unsigned long cause;
+};
+
+#define NR_VECTORS  2
+#define NR_EXCEPTIONS  32
+#define EC_MASK  (NR_EXCEPTIONS - 1)
+
+typedef void(*exception_handler_fn)(struct ex_regs *);
+
+void vm_init_vector_tables(struct kvm_vm *vm);
+void vcpu_init_vector_tables(struct kvm_vcpu *vcpu);
+
+void vm_install_exception_handler(struct kvm_vm *vm, int vector, exception_handler_fn handler);
+
+void vm_install_interrupt_handler(struct kvm_vm *vm, exception_handler_fn handler);
+
 /* L3 index Bit[47:39] */
 #define PGTBL_L3_INDEX_MASK			0x0000FF8000000000ULL
 #define PGTBL_L3_INDEX_SHIFT			39
@@ -101,13 +154,6 @@ static inline uint64_t __kvm_reg_id(uint64_t type, uint64_t subtype,
 #define PGTBL_PAGE_SIZE				PGTBL_L0_BLOCK_SIZE
 #define PGTBL_PAGE_SIZE_SHIFT			PGTBL_L0_BLOCK_SHIFT
 
-#define SATP_PPN				_AC(0x00000FFFFFFFFFFF, UL)
-#define SATP_MODE_39				_AC(0x8000000000000000, UL)
-#define SATP_MODE_48				_AC(0x9000000000000000, UL)
-#define SATP_ASID_BITS				16
-#define SATP_ASID_SHIFT				44
-#define SATP_ASID_MASK				_AC(0xFFFF, UL)
-
 /* SBI return error codes */
 #define SBI_SUCCESS				0
 #define SBI_ERR_FAILURE				-1
@@ -147,4 +193,14 @@ struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0,
 
 bool guest_sbi_probe_extension(int extid, long *out_val);
 
+static inline void local_irq_enable(void)
+{
+	csr_set(CSR_SSTATUS, SR_SIE);
+}
+
+static inline void local_irq_disable(void)
+{
+	csr_clear(CSR_SSTATUS, SR_SIE);
+}
+
 #endif /* SELFTEST_KVM_PROCESSOR_H */

tools/testing/selftests/kvm/include/test_util.h

@@ -20,6 +20,8 @@
 #include <sys/mman.h>
 #include "kselftest.h"
 
+#define msecs_to_usecs(msec)    ((msec) * 1000ULL)
+
 static inline int _no_printf(const char *format, ...) { return 0; }
 
 #ifdef DEBUG

tools/testing/selftests/kvm/include/timer_test.h

+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * timer test specific header
+ *
+ * Copyright (C) 2018, Google LLC
+ */
+
+#ifndef SELFTEST_KVM_TIMER_TEST_H
+#define SELFTEST_KVM_TIMER_TEST_H
+
+#include "kvm_util.h"
+
+#define NR_VCPUS_DEF            4
+#define NR_TEST_ITERS_DEF       5
+#define TIMER_TEST_PERIOD_MS_DEF    10
+#define TIMER_TEST_ERR_MARGIN_US    100
+#define TIMER_TEST_MIGRATION_FREQ_MS    2
+
+/* Timer test cmdline parameters */
+struct test_args {
+	uint32_t nr_vcpus;
+	uint32_t nr_iter;
+	uint32_t timer_period_ms;
+	uint32_t migration_freq_ms;
+	uint32_t timer_err_margin_us;
+	/* Members of struct kvm_arm_counter_offset */
+	uint64_t counter_offset;
+	uint64_t reserved;
+};
+
+/* Shared variables between host and guest */
+struct test_vcpu_shared_data {
+	uint32_t nr_iter;
+	int guest_stage;
+	uint64_t xcnt;
+};
+
+extern struct test_args test_args;
+extern struct kvm_vcpu *vcpus[];
+extern struct test_vcpu_shared_data vcpu_shared_data[];
+
+struct kvm_vm *test_vm_create(void);
+void test_vm_cleanup(struct kvm_vm *vm);
+
+#endif /* SELFTEST_KVM_TIMER_TEST_H */

tools/testing/selftests/kvm/lib/riscv/handlers.S

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2023 Intel Corporation
+ */
+
+#ifndef __ASSEMBLY__
+#define __ASSEMBLY__
+#endif
+
+#include <asm/csr.h>
+
+.macro save_context
+	addi  sp, sp, (-8*34)
+	sd    x1, 0(sp)
+	sd    x2, 8(sp)
+	sd    x3, 16(sp)
+	sd    x4, 24(sp)
+	sd    x5, 32(sp)
+	sd    x6, 40(sp)
+	sd    x7, 48(sp)
+	sd    x8, 56(sp)
+	sd    x9, 64(sp)
+	sd    x10, 72(sp)
+	sd    x11, 80(sp)
+	sd    x12, 88(sp)
+	sd    x13, 96(sp)
+	sd    x14, 104(sp)
+	sd    x15, 112(sp)
+	sd    x16, 120(sp)
+	sd    x17, 128(sp)
+	sd    x18, 136(sp)
+	sd    x19, 144(sp)
+	sd    x20, 152(sp)
+	sd    x21, 160(sp)
+	sd    x22, 168(sp)
+	sd    x23, 176(sp)
+	sd    x24, 184(sp)
+	sd    x25, 192(sp)
+	sd    x26, 200(sp)
+	sd    x27, 208(sp)
+	sd    x28, 216(sp)
+	sd    x29, 224(sp)
+	sd    x30, 232(sp)
+	sd    x31, 240(sp)
+	csrr  s0, CSR_SEPC
+	csrr  s1, CSR_SSTATUS
+	csrr  s2, CSR_SCAUSE
+	sd    s0, 248(sp)
+	sd    s1, 256(sp)
+	sd    s2, 264(sp)
+.endm
+
+.macro restore_context
+	ld    s2, 264(sp)
+	ld    s1, 256(sp)
+	ld    s0, 248(sp)
+	csrw  CSR_SCAUSE, s2
+	csrw  CSR_SSTATUS, s1
+	csrw  CSR_SEPC, s0
+	ld    x31, 240(sp)
+	ld    x30, 232(sp)
+	ld    x29, 224(sp)
+	ld    x28, 216(sp)
+	ld    x27, 208(sp)
+	ld    x26, 200(sp)
+	ld    x25, 192(sp)
+	ld    x24, 184(sp)
+	ld    x23, 176(sp)
+	ld    x22, 168(sp)
+	ld    x21, 160(sp)
+	ld    x20, 152(sp)
+	ld    x19, 144(sp)
+	ld    x18, 136(sp)
+	ld    x17, 128(sp)
+	ld    x16, 120(sp)
+	ld    x15, 112(sp)
+	ld    x14, 104(sp)
+	ld    x13, 96(sp)
+	ld    x12, 88(sp)
+	ld    x11, 80(sp)
+	ld    x10, 72(sp)
+	ld    x9, 64(sp)
+	ld    x8, 56(sp)
+	ld    x7, 48(sp)
+	ld    x6, 40(sp)
+	ld    x5, 32(sp)
+	ld    x4, 24(sp)
+	ld    x3, 16(sp)
+	ld    x2, 8(sp)
+	ld    x1, 0(sp)
+	addi  sp, sp, (8*34)
+.endm
+
+.balign 4
+.global exception_vectors
+exception_vectors:
+	save_context
+	move  a0, sp
+	call  route_exception
+	restore_context
+	sret

tools/testing/selftests/kvm/lib/riscv/processor.c

@@ -13,6 +13,18 @@
 
 #define DEFAULT_RISCV_GUEST_STACK_VADDR_MIN	0xac0000
 
+static vm_vaddr_t exception_handlers;
+
+bool __vcpu_has_ext(struct kvm_vcpu *vcpu, uint64_t ext)
+{
+	unsigned long value = 0;
+	int ret;
+
+	ret = __vcpu_get_reg(vcpu, ext, &value);
+
+	return !ret && !!value;
+}
+
 static uint64_t page_align(struct kvm_vm *vm, uint64_t v)
 {
 	return (v + vm->page_size) & ~(vm->page_size - 1);
@@ -314,6 +326,9 @@ struct kvm_vcpu *vm_arch_vcpu_add(struct kvm_vm *vm, uint32_t vcpu_id,
 	vcpu_set_reg(vcpu, RISCV_CORE_REG(regs.sp), stack_vaddr + stack_size);
 	vcpu_set_reg(vcpu, RISCV_CORE_REG(regs.pc), (unsigned long)guest_code);
 
+	/* Setup sscratch for guest_get_vcpuid() */
+	vcpu_set_reg(vcpu, RISCV_GENERAL_CSR_REG(sscratch), vcpu_id);
+
 	/* Setup default exception vector of guest */
 	vcpu_set_reg(vcpu, RISCV_GENERAL_CSR_REG(stvec), (unsigned long)guest_unexp_trap);
 
@@ -364,8 +379,80 @@ void vcpu_args_set(struct kvm_vcpu *vcpu, unsigned int num, ...)
 	va_end(ap);
 }
 
+void kvm_exit_unexpected_exception(int vector, int ec)
+{
+	ucall(UCALL_UNHANDLED, 2, vector, ec);
+}
+
 void assert_on_unhandled_exception(struct kvm_vcpu *vcpu)
 {
+	struct ucall uc;
+
+	if (get_ucall(vcpu, &uc) == UCALL_UNHANDLED) {
+		TEST_FAIL("Unexpected exception (vector:0x%lx, ec:0x%lx)",
+			uc.args[0], uc.args[1]);
+	}
+}
+
+struct handlers {
+	exception_handler_fn exception_handlers[NR_VECTORS][NR_EXCEPTIONS];
+};
+
+void route_exception(struct ex_regs *regs)
+{
+	struct handlers *handlers = (struct handlers *)exception_handlers;
+	int vector = 0, ec;
+
+	ec = regs->cause & ~CAUSE_IRQ_FLAG;
+	if (ec >= NR_EXCEPTIONS)
+		goto unexpected_exception;
+
+	/* Use the same handler for all the interrupts */
+	if (regs->cause & CAUSE_IRQ_FLAG) {
+		vector = 1;
+		ec = 0;
+	}
+
+	if (handlers && handlers->exception_handlers[vector][ec])
+		return handlers->exception_handlers[vector][ec](regs);
+
+unexpected_exception:
+	return kvm_exit_unexpected_exception(vector, ec);
+}
+
+void vcpu_init_vector_tables(struct kvm_vcpu *vcpu)
+{
+	extern char exception_vectors;
+
+	vcpu_set_reg(vcpu, RISCV_GENERAL_CSR_REG(stvec), (unsigned long)&exception_vectors);
+}
+
+void vm_init_vector_tables(struct kvm_vm *vm)
+{
+	vm->handlers = __vm_vaddr_alloc(vm, sizeof(struct handlers),
+				   vm->page_size, MEM_REGION_DATA);
+
+	*(vm_vaddr_t *)addr_gva2hva(vm, (vm_vaddr_t)(&exception_handlers)) = vm->handlers;
+}
+
+void vm_install_exception_handler(struct kvm_vm *vm, int vector, exception_handler_fn handler)
+{
+	struct handlers *handlers = addr_gva2hva(vm, vm->handlers);
+
+	assert(vector < NR_EXCEPTIONS);
+	handlers->exception_handlers[0][vector] = handler;
+}
+
+void vm_install_interrupt_handler(struct kvm_vm *vm, exception_handler_fn handler)
+{
+	struct handlers *handlers = addr_gva2hva(vm, vm->handlers);
+
+	handlers->exception_handlers[1][0] = handler;
+}
+
+uint32_t guest_get_vcpuid(void)
+{
+	return csr_read(CSR_SSCRATCH);
 }
 
 struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0,

tools/testing/selftests/kvm/riscv/arch_timer.c

+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * arch_timer.c - Tests the riscv64 sstc timer IRQ functionality
+ *
+ * The test validates the sstc timer IRQs using vstimecmp registers.
+ * It's ported from the aarch64 arch_timer test.
+ *
+ * Copyright (c) 2024, Intel Corporation.
+ */
+
+#define _GNU_SOURCE
+
+#include "arch_timer.h"
+#include "kvm_util.h"
+#include "processor.h"
+#include "timer_test.h"
+
+static int timer_irq = IRQ_S_TIMER;
+
+static void guest_irq_handler(struct ex_regs *regs)
+{
+	uint64_t xcnt, xcnt_diff_us, cmp;
+	unsigned int intid = regs->cause & ~CAUSE_IRQ_FLAG;
+	uint32_t cpu = guest_get_vcpuid();
+	struct test_vcpu_shared_data *shared_data = &vcpu_shared_data[cpu];
+
+	timer_irq_disable();
+
+	xcnt = timer_get_cycles();
+	cmp = timer_get_cmp();
+	xcnt_diff_us = cycles_to_usec(xcnt - shared_data->xcnt);
+
+	/* Make sure we are dealing with the correct timer IRQ */
+	GUEST_ASSERT_EQ(intid, timer_irq);
+
+	__GUEST_ASSERT(xcnt >= cmp,
+			"xcnt = 0x%"PRIx64", cmp = 0x%"PRIx64", xcnt_diff_us = 0x%" PRIx64,
+			xcnt, cmp, xcnt_diff_us);
+
+	WRITE_ONCE(shared_data->nr_iter, shared_data->nr_iter + 1);
+}
+
+static void guest_run(struct test_vcpu_shared_data *shared_data)
+{
+	uint32_t irq_iter, config_iter;
+
+	shared_data->nr_iter = 0;
+	shared_data->guest_stage = 0;
+
+	for (config_iter = 0; config_iter < test_args.nr_iter; config_iter++) {
+		/* Setup the next interrupt */
+		timer_set_next_cmp_ms(test_args.timer_period_ms);
+		shared_data->xcnt = timer_get_cycles();
+		timer_irq_enable();
+
+		/* Setup a timeout for the interrupt to arrive */
+		udelay(msecs_to_usecs(test_args.timer_period_ms) +
+			test_args.timer_err_margin_us);
+
+		irq_iter = READ_ONCE(shared_data->nr_iter);
+		__GUEST_ASSERT(config_iter + 1 == irq_iter,
+				"config_iter + 1 = 0x%x, irq_iter = 0x%x.\n"
+				"  Guest timer interrupt was not trigged within the specified\n"
+				"  interval, try to increase the error margin by [-e] option.\n",
+				config_iter + 1, irq_iter);
+	}
+}
+
+static void guest_code(void)
+{
+	uint32_t cpu = guest_get_vcpuid();
+	struct test_vcpu_shared_data *shared_data = &vcpu_shared_data[cpu];
+
+	timer_irq_disable();
+	local_irq_enable();
+
+	guest_run(shared_data);
+
+	GUEST_DONE();
+}
+
+struct kvm_vm *test_vm_create(void)
+{
+	struct kvm_vm *vm;
+	int nr_vcpus = test_args.nr_vcpus;
+
+	vm = vm_create_with_vcpus(nr_vcpus, guest_code, vcpus);
+	__TEST_REQUIRE(__vcpu_has_ext(vcpus[0], RISCV_ISA_EXT_REG(KVM_RISCV_ISA_EXT_SSTC)),
+				   "SSTC not available, skipping test\n");
+
+	vm_init_vector_tables(vm);
+	vm_install_interrupt_handler(vm, guest_irq_handler);
+
+	for (int i = 0; i < nr_vcpus; i++)
+		vcpu_init_vector_tables(vcpus[i]);
+
+	/* Initialize guest timer frequency. */
+	vcpu_get_reg(vcpus[0], RISCV_TIMER_REG(frequency), &timer_freq);
+	sync_global_to_guest(vm, timer_freq);
+	pr_debug("timer_freq: %lu\n", timer_freq);
+
+	/* Make all the test's cmdline args visible to the guest */
+	sync_global_to_guest(vm, test_args);
+
+	return vm;
+}
+
+void test_vm_cleanup(struct kvm_vm *vm)
+{
+	kvm_vm_free(vm);
+}

tools/testing/selftests/kvm/riscv/get-reg-list.c

@@ -47,6 +47,7 @@ bool filter_reg(__u64 reg)
 	case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_SVINVAL:
 	case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_SVNAPOT:
 	case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_SVPBMT:
+	case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_ZACAS:
 	case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_ZBA:
 	case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_ZBB:
 	case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_ZBC:
@@ -73,6 +74,7 @@ bool filter_reg(__u64 reg)
 	case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_ZKSED:
 	case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_ZKSH:
 	case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_ZKT:
+	case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_ZTSO:
 	case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_ZVBB:
 	case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_ZVBC:
 	case KVM_REG_RISCV_ISA_EXT | KVM_REG_RISCV_ISA_SINGLE | KVM_RISCV_ISA_EXT_ZVFH:
@@ -123,15 +125,6 @@ bool check_reject_set(int err)
 	return err == EINVAL;
 }
 
-static bool vcpu_has_ext(struct kvm_vcpu *vcpu, uint64_t ext_id)
-{
-	int ret;
-	unsigned long value;
-
-	ret = __vcpu_get_reg(vcpu, ext_id, &value);
-	return (ret) ? false : !!value;
-}
-
 void finalize_vcpu(struct kvm_vcpu *vcpu, struct vcpu_reg_list *c)
 {
 	unsigned long isa_ext_state[KVM_RISCV_ISA_EXT_MAX] = { 0 };
@@ -176,7 +169,7 @@ void finalize_vcpu(struct kvm_vcpu *vcpu, struct vcpu_reg_list *c)
 		__vcpu_set_reg(vcpu, feature, 1);
 
 		/* Double check whether the desired extension was enabled */
-		__TEST_REQUIRE(vcpu_has_ext(vcpu, feature),
+		__TEST_REQUIRE(__vcpu_has_ext(vcpu, feature),
 			       "%s not available, skipping tests", s->name);
 	}
 }
@@ -419,6 +412,7 @@ static const char *isa_ext_single_id_to_str(__u64 reg_off)
 		KVM_ISA_EXT_ARR(SVINVAL),
 		KVM_ISA_EXT_ARR(SVNAPOT),
 		KVM_ISA_EXT_ARR(SVPBMT),
+		KVM_ISA_EXT_ARR(ZACAS),
 		KVM_ISA_EXT_ARR(ZBA),
 		KVM_ISA_EXT_ARR(ZBB),
 		KVM_ISA_EXT_ARR(ZBC),
@@ -445,6 +439,7 @@ static const char *isa_ext_single_id_to_str(__u64 reg_off)
 		KVM_ISA_EXT_ARR(ZKSED),
 		KVM_ISA_EXT_ARR(ZKSH),
 		KVM_ISA_EXT_ARR(ZKT),
+		KVM_ISA_EXT_ARR(ZTSO),
 		KVM_ISA_EXT_ARR(ZVBB),
 		KVM_ISA_EXT_ARR(ZVBC),
 		KVM_ISA_EXT_ARR(ZVFH),
@@ -940,6 +935,7 @@ KVM_ISA_EXT_SIMPLE_CONFIG(sstc, SSTC);
 KVM_ISA_EXT_SIMPLE_CONFIG(svinval, SVINVAL);
 KVM_ISA_EXT_SIMPLE_CONFIG(svnapot, SVNAPOT);
 KVM_ISA_EXT_SIMPLE_CONFIG(svpbmt, SVPBMT);
+KVM_ISA_EXT_SIMPLE_CONFIG(zacas, ZACAS);
 KVM_ISA_EXT_SIMPLE_CONFIG(zba, ZBA);
 KVM_ISA_EXT_SIMPLE_CONFIG(zbb, ZBB);
 KVM_ISA_EXT_SIMPLE_CONFIG(zbc, ZBC);
@@ -966,6 +962,7 @@ KVM_ISA_EXT_SIMPLE_CONFIG(zkr, ZKR);
 KVM_ISA_EXT_SIMPLE_CONFIG(zksed, ZKSED);
 KVM_ISA_EXT_SIMPLE_CONFIG(zksh, ZKSH);
 KVM_ISA_EXT_SIMPLE_CONFIG(zkt, ZKT);
+KVM_ISA_EXT_SIMPLE_CONFIG(ztso, ZTSO);
 KVM_ISA_EXT_SIMPLE_CONFIG(zvbb, ZVBB);
 KVM_ISA_EXT_SIMPLE_CONFIG(zvbc, ZVBC);
 KVM_ISA_EXT_SIMPLE_CONFIG(zvfh, ZVFH);
@@ -993,6 +990,7 @@ struct vcpu_reg_list *vcpu_configs[] = {
 	&config_svinval,
 	&config_svnapot,
 	&config_svpbmt,
+	&config_zacas,
 	&config_zba,
 	&config_zbb,
 	&config_zbc,
@@ -1019,6 +1017,7 @@ struct vcpu_reg_list *vcpu_configs[] = {
 	&config_zksed,
 	&config_zksh,
 	&config_zkt,
+	&config_ztso,
 	&config_zvbb,
 	&config_zvbc,
 	&config_zvfh,