Covers fundamental tests for debug exceptions. The guest installs and
handle its debug exceptions itself, without KVM_SET_GUEST_DEBUG.
Signed-off-by: Ricardo Koller <ricarkol@xxxxxxxxxx>
---
tools/testing/selftests/kvm/.gitignore | 1 +
tools/testing/selftests/kvm/Makefile | 1 +
.../selftests/kvm/aarch64/debug-exceptions.c | 250 ++++++++++++++++++
.../selftests/kvm/include/aarch64/processor.h | 17 ++
4 files changed, 269 insertions(+)
create mode 100644 tools/testing/selftests/kvm/aarch64/debug-exceptions.c
diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore
index e65d5572aefc..f09ed908422b 100644
--- a/tools/testing/selftests/kvm/.gitignore
+++ b/tools/testing/selftests/kvm/.gitignore
@@ -1,4 +1,5 @@
# SPDX-License-Identifier: GPL-2.0-only
+/aarch64/debug-exceptions
/aarch64/get-reg-list
/aarch64/get-reg-list-sve
/aarch64/vgic_init
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index 618c5903f478..2f92442c0cc9 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -73,6 +73,7 @@ TEST_GEN_PROGS_x86_64 += memslot_modification_stress_test
TEST_GEN_PROGS_x86_64 += set_memory_region_test
TEST_GEN_PROGS_x86_64 += steal_time
+TEST_GEN_PROGS_aarch64 += aarch64/debug-exceptions
TEST_GEN_PROGS_aarch64 += aarch64/get-reg-list
TEST_GEN_PROGS_aarch64 += aarch64/get-reg-list-sve
TEST_GEN_PROGS_aarch64 += aarch64/vgic_init
diff --git a/tools/testing/selftests/kvm/aarch64/debug-exceptions.c b/tools/testing/selftests/kvm/aarch64/debug-exceptions.c
new file mode 100644
index 000000000000..18e8de2711d3
--- /dev/null
+++ b/tools/testing/selftests/kvm/aarch64/debug-exceptions.c
@@ -0,0 +1,250 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE /* for program_invocation_short_name */
+#include <fcntl.h>
+#include <pthread.h>
+#include <sched.h>
+#include <semaphore.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <asm/barrier.h>
+
+#include <linux/compiler.h>
+
+#include <test_util.h>
+#include <kvm_util.h>
+#include <processor.h>
+
+#define VCPU_ID 0
+
+extern unsigned char sw_bp, hw_bp, bp_svc, bp_brk, hw_wp, ss_start;
+static volatile uint64_t sw_bp_addr, hw_bp_addr;
+static volatile uint64_t wp_addr, wp_data_addr;
+static volatile uint64_t svc_addr;
+static volatile uint64_t ss_addr[4], ss_idx;
+#define CAST_TO_PC(v) ((uint64_t)&(v))
+
+static void reset_debug_state(void)
+{
+ asm volatile("msr daifset, #8");
+
+ write_sysreg(osdlr_el1, 0);
+ write_sysreg(oslar_el1, 0);
+ asm volatile("isb" : : : "memory");
+
+ write_sysreg(mdscr_el1, 0);
+ /* This test only uses the first bp and wp slot. */
+ write_sysreg(dbgbvr0_el1, 0);
+ write_sysreg(dbgbcr0_el1, 0);
+ write_sysreg(dbgwcr0_el1, 0);
+ write_sysreg(dbgwvr0_el1, 0);
+ asm volatile("isb" : : : "memory");
+}
+
+static void install_wp(uint64_t addr)
+{
+ uint32_t wcr;
+ uint32_t mdscr;
+
+ wcr = DBGWCR_LEN8 | DBGWCR_RD | DBGWCR_WR | DBGWCR_EL1 | DBGWCR_E;
+ write_sysreg(dbgwcr0_el1, wcr);
+ write_sysreg(dbgwvr0_el1, addr);
+ asm volatile("isb" : : : "memory");
+
+ asm volatile("msr daifclr, #8");
+
+ mdscr = read_sysreg(mdscr_el1) | MDSCR_KDE | MDSCR_MDE;
+ write_sysreg(mdscr_el1, mdscr);
+}
+
+static void install_hw_bp(uint64_t addr)
+{
+ uint32_t bcr;
+ uint32_t mdscr;
+
+ bcr = DBGBCR_LEN8 | DBGBCR_EXEC | DBGBCR_EL1 | DBGBCR_E;
+ write_sysreg(dbgbcr0_el1, bcr);
+ write_sysreg(dbgbvr0_el1, addr);
+ asm volatile("isb" : : : "memory");
+
+ asm volatile("msr daifclr, #8");
+
+ mdscr = read_sysreg(mdscr_el1) | MDSCR_KDE | MDSCR_MDE;
+ write_sysreg(mdscr_el1, mdscr);
+}
+
+static void install_ss(void)
+{
+ uint32_t mdscr;
+
+ asm volatile("msr daifclr, #8");
+
+ mdscr = read_sysreg(mdscr_el1) | MDSCR_KDE | MDSCR_SS;
+ write_sysreg(mdscr_el1, mdscr);
+}
+
+static volatile char write_data;
+
+#define GUEST_ASSERT_EQ(arg1, arg2) \
+ GUEST_ASSERT_2((arg1) == (arg2), (arg1), (arg2))
+
+static void guest_code(void)
+{
+ GUEST_SYNC(0);
+
+ /* Software-breakpoint */
+ asm volatile("sw_bp: brk #0");
+ GUEST_ASSERT_EQ(sw_bp_addr, CAST_TO_PC(sw_bp));
+
+ GUEST_SYNC(1);
+
+ /* Hardware-breakpoint */
+ reset_debug_state();
+ install_hw_bp(CAST_TO_PC(hw_bp));
+ asm volatile("hw_bp: nop");
+ GUEST_ASSERT_EQ(hw_bp_addr, CAST_TO_PC(hw_bp));
+
+ GUEST_SYNC(2);
+
+ /* Hardware-breakpoint + svc */
+ reset_debug_state();
+ install_hw_bp(CAST_TO_PC(bp_svc));
+ asm volatile("bp_svc: svc #0");
+ GUEST_ASSERT_EQ(hw_bp_addr, CAST_TO_PC(bp_svc));
+ GUEST_ASSERT_EQ(svc_addr, CAST_TO_PC(bp_svc) + 4);
+
+ GUEST_SYNC(3);
+
+ /* Hardware-breakpoint + software-breakpoint */
+ reset_debug_state();
+ install_hw_bp(CAST_TO_PC(bp_brk));
+ asm volatile("bp_brk: brk #0");
+ GUEST_ASSERT_EQ(sw_bp_addr, CAST_TO_PC(bp_brk));
+ GUEST_ASSERT_EQ(hw_bp_addr, CAST_TO_PC(bp_brk));
+
+ GUEST_SYNC(4);
+
+ /* Watchpoint */
+ reset_debug_state();
+ install_wp(CAST_TO_PC(write_data));
+ write_data = 'x';
+ GUEST_ASSERT_EQ(write_data, 'x');
+ GUEST_ASSERT_EQ(wp_data_addr, CAST_TO_PC(write_data));
+
+ GUEST_SYNC(5);
+
+ /* Single-step */
+ reset_debug_state();
+ install_ss();
+ ss_idx = 0;
+ asm volatile("ss_start:\n"
+ "mrs x0, esr_el1\n"
+ "add x0, x0, #1\n"
+ "msr daifset, #8\n"
+ : : : "x0");
+ GUEST_ASSERT_EQ(ss_addr[0], CAST_TO_PC(ss_start));
+ GUEST_ASSERT_EQ(ss_addr[1], CAST_TO_PC(ss_start) + 4);
+ GUEST_ASSERT_EQ(ss_addr[2], CAST_TO_PC(ss_start) + 8);
+
+ GUEST_DONE();
+}
+
+static void guest_sw_bp_handler(struct ex_regs *regs)
+{
+ sw_bp_addr = regs->pc;
+ regs->pc += 4;
+}
+
+static void guest_hw_bp_handler(struct ex_regs *regs)
+{
+ hw_bp_addr = regs->pc;
+ regs->pstate |= SPSR_D;
+}
+
+static void guest_wp_handler(struct ex_regs *regs)
+{
+ wp_data_addr = read_sysreg(far_el1);
+ wp_addr = regs->pc;
+ regs->pstate |= SPSR_D;
+}
+
+static void guest_ss_handler(struct ex_regs *regs)
+{
+ GUEST_ASSERT_1(ss_idx < 4, ss_idx);
+ ss_addr[ss_idx++] = regs->pc;
+ regs->pstate |= SPSR_SS;
+}
+
+static void guest_svc_handler(struct ex_regs *regs)
+{
+ svc_addr = regs->pc;
+}
+
+static int debug_version(struct kvm_vm *vm)
+{
+ uint64_t id_aa64dfr0;
+
+ get_reg(vm, VCPU_ID, ARM64_SYS_REG(ID_AA64DFR0_EL1), &id_aa64dfr0);
+ return id_aa64dfr0 & 0xf;
+}
+
+int main(int argc, char *argv[])
+{
+ struct kvm_vm *vm;
+ struct ucall uc;
+ int stage;
+ int ret;
+
+ 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);
+
+ if (debug_version(vm) < 6) {
+ print_skip("Armv8 debug architecture not supported.");
+ kvm_vm_free(vm);
+ exit(KSFT_SKIP);
+ }
+
+ vm_handle_exception(vm, VECTOR_SYNC_EL1,
+ ESR_EC_BRK_INS, guest_sw_bp_handler);
+ vm_handle_exception(vm, VECTOR_SYNC_EL1,
+ ESR_EC_HW_BP_EL1, guest_hw_bp_handler);
+ vm_handle_exception(vm, VECTOR_SYNC_EL1,
+ ESR_EC_WP_EL1, guest_wp_handler);
+ vm_handle_exception(vm, VECTOR_SYNC_EL1,
+ ESR_EC_SSTEP_EL1, guest_ss_handler);
+ vm_handle_exception(vm, VECTOR_SYNC_EL1,
+ ESR_EC_SVC64, guest_svc_handler);
+
+ for (stage = 0; stage < 7; stage++) {
+ ret = _vcpu_run(vm, VCPU_ID);
+
+ TEST_ASSERT(ret == 0, "vcpu_run failed: %d\n", ret);
+ switch (get_ucall(vm, VCPU_ID, &uc)) {
+ case UCALL_SYNC:
+ TEST_ASSERT(uc.args[1] == stage,
+ "Stage %d: Unexpected sync ucall, got %lx",
+ stage, (ulong)uc.args[1]);
+
+ 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:
+ kvm_vm_free(vm);
+ return 0;
+}
diff --git a/tools/testing/selftests/kvm/include/aarch64/processor.h b/tools/testing/selftests/kvm/include/aarch64/processor.h
index 5c902ad95c35..eee69b92e01e 100644
--- a/tools/testing/selftests/kvm/include/aarch64/processor.h
+++ b/tools/testing/selftests/kvm/include/aarch64/processor.h
@@ -21,6 +21,8 @@
#define SCTLR_EL1 3, 0, 1, 0, 0
#define VBAR_EL1 3, 0, 12, 0, 0
+#define ID_AA64DFR0_EL1 3, 0, 0, 5, 0
+
/*
* Default MAIR
* index attribute
@@ -125,4 +127,19 @@ void vm_handle_exception(struct kvm_vm *vm, int vector, int ec,
val; \
})
+#define MDSCR_KDE (1 << 13)
+#define MDSCR_MDE (1 << 15)
+#define MDSCR_SS (1 << 0)
+
+#define DBGBCR_LEN8 (0xff << 5)
+#define DBGBCR_EXEC (0x0 << 3)
+#define DBGBCR_EL1 (0x1 << 1)
+#define DBGBCR_E (0x1 << 0)
+
+#define DBGWCR_LEN8 (0xff << 5)
+#define DBGWCR_RD (0x1 << 3)
+#define DBGWCR_WR (0x2 << 3)
+#define DBGWCR_EL1 (0x1 << 1)
+#define DBGWCR_E (0x1 << 0)
+
#endif /* SELFTEST_KVM_PROCESSOR_H */
--
2.31.1.498.g6c1eba8ee3d-goog
