KVM: add vmdos_buslock_de case

KVM/qemu/buslock_de.cfg

@@ -0,0 +1,58 @@
+- buslock_de:
+    type = buslock_de
+    only Linux
+    virt_test_type = qemu
+    vm_accelerator = kvm
+    force_create_image = no
+    remove_image = no
+    start_vm = yes
+    kill_vm = yes
+    auto_cpu_model = "no"
+    cpu_model = host
+    vga = std
+    test_dir = '/tmp'
+    reboot_settle_time = 20
+    cmdline_check_retry = 3
+    cmdline_check_retry_sleep = 5
+    cpuid_src_subdir = tools/cpuid_check
+    cpuid_source_file = 'cpuid_check.c'
+    cpuid_exec_file = 'cpuid_check'
+    cpuid = "7 0 0 0 c 24"
+    deps_subdir = "bus_lock"
+    bus_lock_source_file = bus_lock.c
+    bus_lock_exec_file = bus_lock.out
+    bus_lock_common_file = bus_lock_common.h
+    variants:
+        - buslock_de_warn:
+            split_lock_mode = warn
+            expected_msr_bit = 1
+            expected_dmesg_delta = ge1
+            check_core_dump = yes
+            expect_exception_nmi = yes
+        - buslock_de_off:
+            split_lock_mode = off
+            expected_msr_bit = 0
+            expected_dmesg_delta = zero
+            expect_exception_nmi = no
+        - buslock_de_fatal:
+            split_lock_mode = fatal
+            expected_msr_bit = 1
+            expected_dmesg_delta = zero
+            expect_bus_error = yes
+            expect_exception_nmi = yes
+        - buslock_de_ratelimit:
+            split_lock_mode = ratelimit:5
+            bus_lock_source_file = bus_lock_10.c
+            bus_lock_exec_file = bus_lock_10.out
+            expected_msr_bit = 1
+            expected_dmesg_delta = exact
+            expected_dmesg_count = 5
+            expect_exception_nmi = yes
+            ratelimit_retry = yes
+    variants:
+        - vm:
+        - td:
+            machine_type_extra_params = "kernel-irqchip=split"
+            vm_secure_guest_type = tdx
+            bus_lock_source_file_tdx = bus_lock_64.c
+            bus_lock_exec_file_tdx = bus_lock_64.out

KVM/qemu/deps/bus_lock/bus_lock.c

@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright (c) 2026 Intel Corporation
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "bus_lock_common.h"
+
+int main(void)
+{
+	unsigned char *buffer;
+	int *int_ptr;
+	int cache_line_size;
+
+	cache_line_size = get_cache_line_size_cpuid();
+	printf("The cache line size is %d bytes.\n", cache_line_size);
+
+	buffer = (unsigned char *)aligned_alloc(cache_line_size,
+			 2 * cache_line_size);
+	int_ptr = (int *)(buffer + cache_line_size - 1);
+	locked_add_1(int_ptr);
+
+	return 0;
+}

KVM/qemu/deps/bus_lock/bus_lock_10.c

@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright (c) 2026 Intel Corporation
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "bus_lock_common.h"
+
+int main(void)
+{
+	unsigned char *buffer;
+	int *int_ptr;
+	int cache_line_size;
+	int idx;
+
+	cache_line_size = get_cache_line_size_cpuid();
+	printf("The cache line size is %d bytes.\n", cache_line_size);
+
+	buffer = (unsigned char *)aligned_alloc(cache_line_size,
+			 2 * cache_line_size);
+	int_ptr = (int *)(buffer + cache_line_size - 1);
+
+	for (idx = 0; idx < 10; idx++)
+		locked_add_1(int_ptr);
+
+	return 0;
+}

KVM/qemu/deps/bus_lock/bus_lock_64.c

@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright (c) 2026 Intel Corporation
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "bus_lock_common.h"
+
+int main(void)
+{
+	unsigned char *buffer;
+	int *int_ptr;
+	int cache_line_size;
+	int idx;
+
+	cache_line_size = 64;
+	printf("The cache line size is %d bytes.\n", cache_line_size);
+
+	/* allocate a cache_line_size aligned memory */
+	buffer = (unsigned char *)aligned_alloc(cache_line_size,
+			 2 * cache_line_size);
+
+	/*
+	 * Increment the pointer by cache_line_size - 1, making it 4-byte int_ptr that
+	 * across two cache line
+	 */
+	int_ptr = (int *)(buffer + cache_line_size - 1);
+
+	for (idx = 0; idx < 10; idx++)
+		locked_add_1(int_ptr);
+
+	return 0;
+}

KVM/qemu/deps/bus_lock/bus_lock_common.h

@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright (c) 2026 Intel Corporation */
+
+#ifndef BUS_LOCK_COMMON_H
+#define BUS_LOCK_COMMON_H
+
+#define CPUID_80000006_ECX_CACHE_LINE_SIZE 0x000000FF
+
+static inline void do_cpuid(int leaf, int subleaf, int *eax, int *ebx,
+			    int *ecx, int *edx)
+{
+	asm volatile("cpuid"
+		 : "=a" (*eax),
+		   "=b" (*ebx),
+		   "=c" (*ecx),
+		   "=d" (*edx)
+		 : "0" (leaf), "2" (subleaf)
+		 : "memory");
+}
+
+static inline void locked_add_1(int *ptr)
+{
+	asm volatile("lock; addl $1,%0\n\t"
+		 : "+m"(*ptr)
+		 :
+		 : "memory");
+}
+
+static inline int get_cache_line_size_cpuid(void)
+{
+	int eax, ecx;
+
+	do_cpuid(0x80000006, 0, &eax, &eax, &ecx, &eax);
+	return ecx & CPUID_80000006_ECX_CACHE_LINE_SIZE;
+}
+
+#endif

KVM/qemu/provider/cpuid_utils.py

@@ -0,0 +1,63 @@
+#!/usr/bin/python3
+
+# SPDX-License-Identifier: GPL-2.0-only
+# Copyright (c) 2026 Intel Corporation
+
+"""Shared helpers for compiling and running cpuid check tools."""
+
+from avocado.core import exceptions
+from avocado.utils import process
+
+from virttest import utils_package
+
+
+def prepare_cpuid(test, params, src_dir, vm=None, session=None):
+    """
+    Compile the cpuid test tool in host or guest.
+
+    :param test: QEMU test object
+    :param params: Dictionary with the test parameters
+    :param src_dir: Test tool source code directory of absolute path
+    :param vm: The VM object
+    :param session: Guest session
+    :return: The executable test tool with absolute path
+    """
+    source_file = params["source_file"]
+    exec_file = params["exec_file"]
+    src_cpuid = src_dir + "/" + source_file
+    if session:
+        test_dir = params["test_dir"]
+        vm.copy_files_to(src_cpuid, test_dir)
+    else:
+        test_dir = src_dir
+
+    if not utils_package.package_install("gcc", session):
+        test.cancel("Failed to install package gcc.")
+
+    compile_cmd = "cd %s && gcc %s -o %s" % (test_dir, source_file, exec_file)
+    if session:
+        status = session.cmd_status(compile_cmd)
+    else:
+        status = process.system(compile_cmd, shell=True)
+    if status:
+        raise exceptions.TestError("Test suite compile failed.")
+
+    return test_dir + "/" + exec_file
+
+
+def check_cpuid(cpuid_arg, exec_bin, session=None):
+    """
+    Run cpuid test in host or guest.
+
+    :param cpuid_arg: The feature to be checked
+    :param exec_bin: The executable binary tool with absolute path
+    :param session: Guest session
+    :return: Command exit status
+    """
+    check_cmd = "%s %s" % (exec_bin, cpuid_arg)
+    func = process.getstatusoutput
+    if session:
+        func = session.cmd_status_output
+    status, output = func(check_cmd)
+
+    return status