Add a new KVM selftest, vgic_irq, for testing userspace IRQ injection. This
particular test injects an SPI using KVM_IRQ_LINE on GICv3 and verifies
that the IRQ is handled in the guest. The next commits will add more
types of IRQs and different modes.
Signed-off-by: Ricardo Koller <ricarkol@xxxxxxxxxx>
---
tools/testing/selftests/kvm/.gitignore | 1 +
tools/testing/selftests/kvm/Makefile | 1 +
.../testing/selftests/kvm/aarch64/vgic_irq.c | 244 ++++++++++++++++++
3 files changed, 246 insertions(+)
create mode 100644 tools/testing/selftests/kvm/aarch64/vgic_irq.c
diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore
index d4a830139683..7e59c94f8502 100644
--- a/tools/testing/selftests/kvm/.gitignore
+++ b/tools/testing/selftests/kvm/.gitignore
@@ -4,6 +4,7 @@
/aarch64/get-reg-list
/aarch64/psci_cpu_on_test
/aarch64/vgic_init
+/aarch64/vgic_irq
/s390x/memop
/s390x/resets
/s390x/sync_regs_test
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index c23e89dea0b6..b90e1c9f7c8d 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -93,6 +93,7 @@ TEST_GEN_PROGS_aarch64 += aarch64/debug-exceptions
TEST_GEN_PROGS_aarch64 += aarch64/get-reg-list
TEST_GEN_PROGS_aarch64 += aarch64/psci_cpu_on_test
TEST_GEN_PROGS_aarch64 += aarch64/vgic_init
+TEST_GEN_PROGS_aarch64 += aarch64/vgic_irq
TEST_GEN_PROGS_aarch64 += demand_paging_test
TEST_GEN_PROGS_aarch64 += dirty_log_test
TEST_GEN_PROGS_aarch64 += dirty_log_perf_test
diff --git a/tools/testing/selftests/kvm/aarch64/vgic_irq.c b/tools/testing/selftests/kvm/aarch64/vgic_irq.c
new file mode 100644
index 000000000000..e13e87427038
--- /dev/null
+++ b/tools/testing/selftests/kvm/aarch64/vgic_irq.c
@@ -0,0 +1,244 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * vgic_irq.c - Test userspace injection of IRQs
+ *
+ * This test validates the injection of IRQs from userspace using various
+ * methods (e.g., KVM_IRQ_LINE) and modes (e.g., EOI). The guest "asks" the
+ * host to inject a specific intid via a GUEST_SYNC call, and then checks that
+ * it received it.
+ */
+
+#include <asm/kvm.h>
+#include <asm/kvm_para.h>
+#include <linux/sizes.h>
+
+#include "processor.h"
+#include "test_util.h"
+#include "kvm_util.h"
+#include "gic.h"
+#include "gic_v3.h"
+#include "vgic.h"
+
+#define GICD_BASE_GPA 0x08000000ULL
+#define GICR_BASE_GPA 0x080A0000ULL
+#define VCPU_ID 0
+
+/*
+ * KVM implements 32 priority levels:
+ * 0x00 (highest priority) - 0xF8 (lowest priority), in steps of 8
+ *
+ * Note that these macros will still be correct in the case that KVM implements
+ * more priority levels. Also note that 32 is the minimum for GICv3 and GICv2.
+ */
+#define KVM_NUM_PRIOS 32
+#define KVM_PRIO_SHIFT 3 /* steps of 8 = 1 << 3 */
+#define LOWEST_PRIO (KVM_NUM_PRIOS - 1)
+#define CPU_PRIO_MASK (LOWEST_PRIO << KVM_PRIO_SHIFT) /* 0xf8 */
+#define IRQ_DEFAULT_PRIO (LOWEST_PRIO - 1)
+#define IRQ_DEFAULT_PRIO_REG (IRQ_DEFAULT_PRIO << KVM_PRIO_SHIFT) /* 0xf0 */
+
+static void *dist = (void *)GICD_BASE_GPA;
+static void *redist = (void *)GICR_BASE_GPA;
+
+/*
+ * The kvm_inject_* utilities are used by the guest to ask the host to inject
+ * interrupts (e.g., using the KVM_IRQ_LINE ioctl).
+ */
+
+typedef enum {
+ KVM_INJECT_EDGE_IRQ_LINE = 1,
+} kvm_inject_cmd;
+
+struct kvm_inject_args {
+ kvm_inject_cmd cmd;
+ uint32_t intid;
+};
+
+/* Used on the guest side to perform the hypercall. */
+static void kvm_inject_call(kvm_inject_cmd cmd, uint32_t intid);
+
+/* Used on the host side to get the hypercall info. */
+static void kvm_inject_get_call(struct kvm_vm *vm, struct ucall *uc,
+ struct kvm_inject_args *args);
+
+/* Shared between the guest main thread and the IRQ handlers. */
+volatile uint64_t irq_handled;
+volatile uint32_t irqnr_received[MAX_SPI + 1];
+
+static void reset_stats(void)
+{
+ int i;
+
+ irq_handled = 0;
+ for (i = 0; i <= MAX_SPI; i++)
+ irqnr_received[i] = 0;
+}
+
+static uint64_t gic_read_ap1r0(void)
+{
+ uint64_t reg = read_sysreg_s(SYS_ICV_AP1R0_EL1);
+
+ dsb(sy);
+ return reg;
+}
+
+static void guest_irq_handler(struct ex_regs *regs)
+{
+ uint32_t intid = gic_get_and_ack_irq();
+
+ if (intid == IAR_SPURIOUS)
+ return;
+
+ GUEST_ASSERT(gic_irq_get_active(intid));
+
+ GUEST_ASSERT(!gic_irq_get_pending(intid));
+
+ GUEST_ASSERT(intid < MAX_SPI);
+ irqnr_received[intid] += 1;
+ irq_handled += 1;
+
+ gic_set_eoi(intid);
+ GUEST_ASSERT_EQ(gic_read_ap1r0(), 0);
+
+ GUEST_ASSERT(!gic_irq_get_active(intid));
+ GUEST_ASSERT(!gic_irq_get_pending(intid));
+}
+
+static void kvm_inject_call(kvm_inject_cmd cmd, uint32_t intid)
+{
+ struct kvm_inject_args args = {
+ .cmd = cmd,
+ .intid = intid,
+ };
+ GUEST_SYNC(&args);
+}
+
+#define GUEST_ASSERT_IAR_EMPTY() \
+do { \
+ uint32_t _intid; \
+ _intid = gic_get_and_ack_irq(); \
+ GUEST_ASSERT(_intid == 0 || _intid == IAR_SPURIOUS); \
+} while (0)
+
+static void test_kvm_irq_line(uint32_t intid)
+{
+ reset_stats();
+
+ asm volatile("msr daifset, #2" : : : "memory");
+ kvm_inject_call(KVM_INJECT_EDGE_IRQ_LINE, intid);
+
+ while (irq_handled < 1) {
+ asm volatile("wfi\n"
+ "msr daifclr, #2\n"
+ /* handle IRQ */
+ "msr daifset, #2\n"
+ : : : "memory");
+ }
+ asm volatile("msr daifclr, #2" : : : "memory");
+
+ GUEST_ASSERT_EQ(irq_handled, 1);
+ GUEST_ASSERT_EQ(irqnr_received[intid], 1);
+ GUEST_ASSERT_IAR_EMPTY();
+}
+
+static void guest_code(void)
+{
+ uint32_t i;
+ uint32_t nr_irqs = 64; /* absolute minimum number of IRQs supported. */
+
+ gic_init(GIC_V3, 1, dist, redist);
+
+ for (i = 0; i < nr_irqs; i++) {
+ gic_irq_enable(i);
+ gic_set_priority(i, IRQ_DEFAULT_PRIO_REG);
+ }
+
+ gic_set_priority_mask(CPU_PRIO_MASK);
+
+ local_irq_enable();
+
+ test_kvm_irq_line(MIN_SPI);
+
+ GUEST_DONE();
+}
+
+static void run_guest_cmd(struct kvm_vm *vm, int gic_fd,
+ struct kvm_inject_args *inject_args)
+{
+ kvm_inject_cmd cmd = inject_args->cmd;
+ uint32_t intid = inject_args->intid;
+
+ switch (cmd) {
+ case KVM_INJECT_EDGE_IRQ_LINE:
+ kvm_arm_irq_line(vm, intid, 1);
+ kvm_arm_irq_line(vm, intid, 0);
+ break;
+ default:
+ break;
+ }
+}
+
+static void kvm_inject_get_call(struct kvm_vm *vm, struct ucall *uc,
+ struct kvm_inject_args *args)
+{
+ struct kvm_inject_args *kvm_args_hva;
+ vm_vaddr_t kvm_args_gva;
+
+ kvm_args_gva = uc->args[1];
+ kvm_args_hva = (struct kvm_inject_args *)addr_gva2hva(vm, kvm_args_gva);
+ memcpy(args, kvm_args_hva, sizeof(struct kvm_inject_args));
+}
+
+
+static void test_vgic(void)
+{
+ struct ucall uc;
+ int gic_fd;
+ struct kvm_vm *vm;
+ struct kvm_inject_args inject_args;
+
+ vm = vm_create_default(VCPU_ID, 0, guest_code);
+ ucall_init(vm, NULL);
+
+ vm_init_descriptor_tables(vm);
+ vcpu_init_descriptor_tables(vm, VCPU_ID);
+
+ gic_fd = vgic_v3_setup(vm, 1, GICD_BASE_GPA, GICR_BASE_GPA);
+
+ vm_install_exception_handler(vm, VECTOR_IRQ_CURRENT,
+ guest_irq_handler);
+
+ while (1) {
+ vcpu_run(vm, VCPU_ID);
+
+ switch (get_ucall(vm, VCPU_ID, &uc)) {
+ case UCALL_SYNC:
+ kvm_inject_get_call(vm, &uc, &inject_args);
+ run_guest_cmd(vm, gic_fd, &inject_args);
+ break;
+ case UCALL_ABORT:
+ TEST_FAIL("%s at %s:%ld\n\tvalues: %#lx, %#lx",
+ (const char *)uc.args[0],
+ __FILE__, uc.args[1], uc.args[2], uc.args[3]);
+ break;
+ case UCALL_DONE:
+ goto done;
+ default:
+ TEST_FAIL("Unknown ucall %lu", uc.cmd);
+ }
+ }
+
+done:
+ close(gic_fd);
+ kvm_vm_free(vm);
+}
+
+int main(int ac, char **av)
+{
+ /* Tell stdout not to buffer its content */
+ setbuf(stdout, NULL);
+
+ test_vgic();
+
+ return 0;
+}
--
2.34.0.rc0.344.g81b53c2807-goog
