[PATCH v5 4/4] tests: check KVM ioctl commands decoding
Masatake YAMATO
yamato at redhat.com
Thu Dec 7 14:03:35 UTC 2017
* tests/Makefile.am (check_PROGRAMS): Add ioctl_kvm.
(DECODER_TESTS): Add ioctl_kvm.test.
(EXTRA_DIST): Add ioctl_kvm.expected.
* tests/ioctl_kvm.c: New test target file.
Taken from https://lwn.net/Articles/658512/.
* tests/ioctl_kvm.expected: New expected file.
* tests/ioctl_kvm.test: New test driver.
Changes in v2:
* Skip the test case if kvm.h is not available.
* Skip the test case if opening /dev/kvm is failed.
* Include sys/typtes.h first.
All items are suggested by ldv.
Highlights in v3:
* Build the new test case when __x86_64__ is defined.
* Don't use macros/functions in err.h.
Use macros/functions in tests.h instead.
* Remove redundant inclusion of header files.
All above items are suggested by ldv.
* Add .test and .expected file to Makefile.am.
No Change in v4.
Change in v5:
* Add missing closing curly bracket in the expected pattern.
---
tests/Makefile.am | 3 +
tests/ioctl_kvm.c | 173 +++++++++++++++++++++++++++++++++++++++++++++++
tests/ioctl_kvm.expected | 11 +++
tests/ioctl_kvm.test | 12 ++++
4 files changed, 199 insertions(+)
create mode 100644 tests/ioctl_kvm.c
create mode 100644 tests/ioctl_kvm.expected
create mode 100755 tests/ioctl_kvm.test
diff --git a/tests/Makefile.am b/tests/Makefile.am
index f2109fd4..ba4c0e2b 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -102,6 +102,7 @@ check_PROGRAMS = $(PURE_EXECUTABLES) \
int_0x80 \
ioctl_dm-v \
ioctl_evdev-v \
+ ioctl_kvm \
ioctl_loop-nv \
ioctl_loop-v \
ioctl_nsfs \
@@ -206,6 +207,7 @@ DECODER_TESTS = \
ioctl.test \
ioctl_dm-v.test \
ioctl_dm.test \
+ ioctl_kvm.test \
ioctl_loop-nv.test \
ioctl_nsfs.test \
ioctl_sock_gifconf.test \
@@ -332,6 +334,7 @@ EXTRA_DIST = \
init.sh \
init_delete_module.h \
ioctl-v.sh \
+ ioctl_kvm.expected \
ipc.sh \
ipc_msgbuf.expected \
ksysent.sed \
diff --git a/tests/ioctl_kvm.c b/tests/ioctl_kvm.c
new file mode 100644
index 00000000..9ac1b640
--- /dev/null
+++ b/tests/ioctl_kvm.c
@@ -0,0 +1,173 @@
+/* Based on the program explained on the page, https://lwn.net/Articles/658512/ */
+
+/* Sample code for /dev/kvm API
+ *
+ * Copyright (c) 2015 Intel Corporation
+ * Author: Josh Triplett <josh at joshtriplett.org>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "tests.h"
+
+#if defined(HAVE_LINUX_KVM_H) \
+ && defined(__x86_64__) \
+ && defined(HAVE_STRUCT_KVM_REGS) \
+ && defined(HAVE_STRUCT_KVM_SREGS) \
+ && defined(HAVE_STRUCT_KVM_USERSPACE_MEMORY_REGION)
+
+# include <fcntl.h>
+# include <stdint.h>
+# include <stdio.h>
+# include <stdlib.h>
+# include <string.h>
+# include <sys/ioctl.h>
+# include <sys/mman.h>
+# include <linux/kvm.h>
+
+int main(void)
+{
+ int kvm, vmfd, vcpufd, ret;
+ const uint8_t code[] = {
+ 0xba, 0xf8, 0x03, /* mov $0x3f8, %dx */
+ 0x00, 0xd8, /* add %bl, %al */
+ 0x04, '0', /* add $'0', %al */
+ 0xee, /* out %al, (%dx) */
+ 0xb0, '\n', /* mov $'\n', %al */
+ 0xee, /* out %al, (%dx) */
+ 0xf4, /* hlt */
+ };
+ uint8_t *mem;
+ struct kvm_sregs sregs;
+ size_t mmap_size;
+ struct kvm_run *run;
+
+ kvm = open("/dev/kvm", O_RDWR | O_CLOEXEC);
+ if (kvm == -1)
+ perror_msg_and_skip("open: %s", "/dev/kvm");
+
+ /* Make sure we have the stable version of the API */
+ ret = ioctl(kvm, KVM_GET_API_VERSION, NULL);
+ if (ret == -1)
+ perror_msg_and_skip("Error at KVM_GET_API_VERSION");
+ if (ret != KVM_API_VERSION)
+ error_msg_and_skip("Unexpected KVM_GET_API_VERSION value");
+
+ vmfd = ioctl(kvm, KVM_CREATE_VM, (unsigned long)0);
+ if (vmfd == -1)
+ perror_msg_and_skip("KVM_CREATE_VM");
+
+ /* Allocate one aligned page of guest memory to hold the code. */
+ mem = mmap(NULL, 0x1000, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0);
+ if (mem == MAP_FAILED)
+ perror_msg_and_skip("allocating guest memory");
+ memcpy(mem, code, sizeof(code));
+
+ /* Map it to the second page frame (to avoid the real-mode IDT at 0). */
+ struct kvm_userspace_memory_region region = {
+ .slot = 0,
+ .guest_phys_addr = 0x1000,
+ .memory_size = 0x1000,
+ .userspace_addr = (uintptr_t)mem,
+ };
+ ret = ioctl(vmfd, KVM_SET_USER_MEMORY_REGION, ®ion);
+ if (ret == -1)
+ perror_msg_and_skip("KVM_SET_USER_MEMORY_REGION");
+
+ vcpufd = ioctl(vmfd, KVM_CREATE_VCPU, 0UL);
+ if (vcpufd == -1)
+ perror_msg_and_skip("KVM_CREATE_VCPU");
+
+ /* Map the shared kvm_run structure and following data. */
+ ret = ioctl(kvm, KVM_GET_VCPU_MMAP_SIZE, NULL);
+ if (ret == -1)
+ perror_msg_and_skip("KVM_GET_VCPU_MMAP_SIZE");
+ mmap_size = ret;
+ if (mmap_size < sizeof(*run))
+ error_msg_and_skip("KVM_GET_VCPU_MMAP_SIZE unexpectedly small");
+ run = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED, vcpufd, 0);
+ if (run == MAP_FAILED)
+ perror_msg_and_skip("mmap vcpu");
+
+ /* Initialize CS to point at 0, via a read-modify-write of sregs. */
+ ret = ioctl(vcpufd, KVM_GET_SREGS, &sregs);
+ if (ret == -1)
+ perror_msg_and_skip("KVM_GET_SREGS");
+ sregs.cs.base = 0;
+ sregs.cs.selector = 0;
+ ret = ioctl(vcpufd, KVM_SET_SREGS, &sregs);
+ if (ret == -1)
+ perror_msg_and_skip("KVM_SET_SREGS");
+
+ /* Initialize registers: instruction pointer for our code, addends, and
+ * initial flags required by x86 architecture. */
+ struct kvm_regs regs = {
+ .rip = 0x1000,
+ .rax = 2,
+ .rbx = 2,
+ .rflags = 0x2,
+ };
+ ret = ioctl(vcpufd, KVM_SET_REGS, ®s);
+ if (ret == -1)
+ perror_msg_and_skip("KVM_SET_REGS");
+
+ /* Repeatedly run code and handle VM exits. */
+ while (1) {
+ ret = ioctl(vcpufd, KVM_RUN, NULL);
+ if (ret == -1)
+ perror_msg_and_skip("KVM_RUN");
+ switch (run->exit_reason) {
+ case KVM_EXIT_HLT:
+ puts("KVM_EXIT_HLT");
+ return 0;
+ case KVM_EXIT_IO:
+ if (run->io.direction == KVM_EXIT_IO_OUT
+ && run->io.size == 1
+ && run->io.port == 0x3f8
+ && run->io.count == 1)
+ putchar(*(((char *)run) + run->io.data_offset));
+ else
+ error_msg_and_skip("unhandled KVM_EXIT_IO");
+ break;
+ case KVM_EXIT_FAIL_ENTRY:
+ error_msg_and_skip("KVM_EXIT_FAIL_ENTRY: hardware_entry_failure_reason = 0x%llx",
+ (unsigned long long)run->fail_entry.hardware_entry_failure_reason);
+ case KVM_EXIT_INTERNAL_ERROR:
+ error_msg_and_skip("KVM_EXIT_INTERNAL_ERROR: suberror = 0x%x",
+ run->internal.suberror);
+ default:
+ error_msg_and_skip("exit_reason = 0x%x", run->exit_reason);
+ }
+ }
+}
+#else
+
+#if !defined(HAVE_LINUX_KVM_H)
+SKIP_MAIN_UNDEFINED("HAVE_LINUX_KVM_H")
+#elif !defined( __x86_64__)
+SKIP_MAIN_UNDEFINED("__x86_64__")
+#elif !defined(HAVE_STRUCT_KVM_REGS)
+SKIP_MAIN_UNDEFINED("HAVE_STRUCT_KVM_REGS")
+#elif !defined(HAVE_STRUCT_KVM_SREGS)
+SKIP_MAIN_UNDEFINED("HAVE_STRUCT_KVM_SREGS")
+#elif !defined(HAVE_STRUCT_KVM_USERSPACE_MEMORY_REGION)
+SKIP_MAIN_UNDEFINED("HAVE_STRUCT_KVM_USERSPACE_MEMORY_REGION")
+#endif
+
+#endif
diff --git a/tests/ioctl_kvm.expected b/tests/ioctl_kvm.expected
new file mode 100644
index 00000000..e90ab16e
--- /dev/null
+++ b/tests/ioctl_kvm.expected
@@ -0,0 +1,11 @@
+ioctl\([0-9]+</dev/kvm>, KVM_GET_API_VERSION, 0\) *= 12
+ioctl\([0-9]+</dev/kvm>, KVM_CREATE_VM, 0\) *= [0-9]+<anon_inode:kvm-vm>
+ioctl\([0-9]+<anon_inode:kvm-vm>, KVM_SET_USER_MEMORY_REGION, {slot=0, flags=0, guest_phys_addr=0x1000, memory_size=4096, userspace_addr=0x[0-9a-f]+}\) *= 0
+ioctl\([0-9]+<anon_inode:kvm-vm>, KVM_CREATE_VCPU, 0\) *= [0-9]+<anon_inode:kvm-vcpu>
+ioctl\([0-9]+</dev/kvm>, KVM_GET_VCPU_MMAP_SIZE, 0\) *= [0-9]+
+ioctl\([0-9]+<anon_inode:kvm-vcpu>, KVM_GET_SREGS, {cs={base=0x[0-9a-f]+, limit=[0-9]+, selector=[0-9]+, type=[0-9]+, present=[0-9]+, dpl=[0-9]+, db=[0-9]+, s=[0-9]+, l=[0-9]+, g=[0-9]+, avl=[0-9]+}, ...}\) *= 0
+ioctl\([0-9]+<anon_inode:kvm-vcpu>, KVM_SET_SREGS, {cs={base=0, limit=[0-9]+, selector=0, type=[0-9]+, present=[0-9]+, dpl=[0-9]+, db=[0-9]+, s=[0-9]+, l=[0-9]+, g=[0-9]+, avl=[0-9]+}, ...}\) *= 0
+ioctl\([0-9]+<anon_inode:kvm-vcpu>, KVM_SET_REGS, {rax=0x2, ..., rsp=0, rbp=0, ..., rip=0x1000, rflags=0x2}\) *= 0
+ioctl\([0-9]+<anon_inode:kvm-vcpu>, KVM_RUN, 0\) *= 0
+ioctl\([0-9]+<anon_inode:kvm-vcpu>, KVM_RUN, 0\) *= 0
+ioctl\([0-9]+<anon_inode:kvm-vcpu>, KVM_RUN, 0\) *= 0
diff --git a/tests/ioctl_kvm.test b/tests/ioctl_kvm.test
new file mode 100755
index 00000000..32a40a99
--- /dev/null
+++ b/tests/ioctl_kvm.test
@@ -0,0 +1,12 @@
+#!/bin/sh
+
+# Check decoding of KVM* ioctls.
+
+. "${srcdir=.}/init.sh"
+
+check_prog grep
+run_prog > /dev/null
+run_strace -y -eioctl $args
+match_grep
+
+exit 0
--
2.13.6
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