Port Using the KVM API to Arm64
Work to port the x86 code in https://lwn.net/Articles/658511/ to Arm64.
Current commit is x86 code.
Signed-off-by: Fuad Tabba <tabba@google.com>
diff --git a/kvmtest/kvmtest-arm64.c b/kvmtest/kvmtest-arm64.c
new file mode 100644
index 0000000..dd4c714
--- /dev/null
+++ b/kvmtest/kvmtest-arm64.c
@@ -0,0 +1,146 @@
+/* Sample code for /dev/kvm API
+ *
+ * Copyright (c) 2015 Intel Corporation
+ * Author: Josh Triplett <josh@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 <err.h>
+#include <fcntl.h>
+#include <linux/kvm.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/types.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)
+ err(1, "/dev/kvm");
+
+ /* Make sure we have the stable version of the API */
+ ret = ioctl(kvm, KVM_GET_API_VERSION, NULL);
+ if (ret == -1)
+ err(1, "KVM_GET_API_VERSION");
+ if (ret != 12)
+ errx(1, "KVM_GET_API_VERSION %d, expected 12", ret);
+
+ vmfd = ioctl(kvm, KVM_CREATE_VM, (unsigned long)0);
+ if (vmfd == -1)
+ err(1, "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)
+ err(1, "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 = (uint64_t)mem,
+ };
+ ret = ioctl(vmfd, KVM_SET_USER_MEMORY_REGION, ®ion);
+ if (ret == -1)
+ err(1, "KVM_SET_USER_MEMORY_REGION");
+
+ vcpufd = ioctl(vmfd, KVM_CREATE_VCPU, (unsigned long)0);
+ if (vcpufd == -1)
+ err(1, "KVM_CREATE_VCPU");
+
+ /* Map the shared kvm_run structure and following data. */
+ ret = ioctl(kvm, KVM_GET_VCPU_MMAP_SIZE, NULL);
+ if (ret == -1)
+ err(1, "KVM_GET_VCPU_MMAP_SIZE");
+ mmap_size = ret;
+ if (mmap_size < sizeof(*run))
+ errx(1, "KVM_GET_VCPU_MMAP_SIZE unexpectedly small");
+ run = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED, vcpufd, 0);
+ if (!run)
+ err(1, "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)
+ err(1, "KVM_GET_SREGS");
+ sregs.cs.base = 0;
+ sregs.cs.selector = 0;
+ ret = ioctl(vcpufd, KVM_SET_SREGS, &sregs);
+ if (ret == -1)
+ err(1, "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)
+ err(1, "KVM_SET_REGS");
+
+ /* Repeatedly run code and handle VM exits. */
+ while (1) {
+ ret = ioctl(vcpufd, KVM_RUN, NULL);
+ if (ret == -1)
+ err(1, "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
+ errx(1, "unhandled KVM_EXIT_IO");
+ break;
+ case KVM_EXIT_FAIL_ENTRY:
+ errx(1, "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:
+ errx(1, "KVM_EXIT_INTERNAL_ERROR: suberror = 0x%x", run->internal.suberror);
+ default:
+ errx(1, "exit_reason = 0x%x", run->exit_reason);
+ }
+ }
+}
diff --git a/kvmtest/kvmtest.c b/kvmtest/kvmtest.c
new file mode 100644
index 0000000..dd4c714
--- /dev/null
+++ b/kvmtest/kvmtest.c
@@ -0,0 +1,146 @@
+/* Sample code for /dev/kvm API
+ *
+ * Copyright (c) 2015 Intel Corporation
+ * Author: Josh Triplett <josh@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 <err.h>
+#include <fcntl.h>
+#include <linux/kvm.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/types.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)
+ err(1, "/dev/kvm");
+
+ /* Make sure we have the stable version of the API */
+ ret = ioctl(kvm, KVM_GET_API_VERSION, NULL);
+ if (ret == -1)
+ err(1, "KVM_GET_API_VERSION");
+ if (ret != 12)
+ errx(1, "KVM_GET_API_VERSION %d, expected 12", ret);
+
+ vmfd = ioctl(kvm, KVM_CREATE_VM, (unsigned long)0);
+ if (vmfd == -1)
+ err(1, "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)
+ err(1, "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 = (uint64_t)mem,
+ };
+ ret = ioctl(vmfd, KVM_SET_USER_MEMORY_REGION, ®ion);
+ if (ret == -1)
+ err(1, "KVM_SET_USER_MEMORY_REGION");
+
+ vcpufd = ioctl(vmfd, KVM_CREATE_VCPU, (unsigned long)0);
+ if (vcpufd == -1)
+ err(1, "KVM_CREATE_VCPU");
+
+ /* Map the shared kvm_run structure and following data. */
+ ret = ioctl(kvm, KVM_GET_VCPU_MMAP_SIZE, NULL);
+ if (ret == -1)
+ err(1, "KVM_GET_VCPU_MMAP_SIZE");
+ mmap_size = ret;
+ if (mmap_size < sizeof(*run))
+ errx(1, "KVM_GET_VCPU_MMAP_SIZE unexpectedly small");
+ run = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED, vcpufd, 0);
+ if (!run)
+ err(1, "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)
+ err(1, "KVM_GET_SREGS");
+ sregs.cs.base = 0;
+ sregs.cs.selector = 0;
+ ret = ioctl(vcpufd, KVM_SET_SREGS, &sregs);
+ if (ret == -1)
+ err(1, "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)
+ err(1, "KVM_SET_REGS");
+
+ /* Repeatedly run code and handle VM exits. */
+ while (1) {
+ ret = ioctl(vcpufd, KVM_RUN, NULL);
+ if (ret == -1)
+ err(1, "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
+ errx(1, "unhandled KVM_EXIT_IO");
+ break;
+ case KVM_EXIT_FAIL_ENTRY:
+ errx(1, "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:
+ errx(1, "KVM_EXIT_INTERNAL_ERROR: suberror = 0x%x", run->internal.suberror);
+ default:
+ errx(1, "exit_reason = 0x%x", run->exit_reason);
+ }
+ }
+}
