feat: Enhance SVM support and improve PIT handling for Linux guests

os/axvisor/configs/vms/linux-x86_64-qemu-smp1-svm.toml

@@ -0,0 +1,81 @@
+# Vm base info configs
+#
+[base]
+# Guest vm id.
+id = 1
+# Guest vm name.
+name = "linux-x86_64-qemu-svm"
+# Virtualization type.
+vm_type = 1
+# The number of virtual CPUs.
+cpu_num = 1
+# Guest vm physical cpu sets.
+phys_cpu_sets = [1]
+
+#
+# Vm kernel configs
+#
+[kernel]
+# The entry point of the kernel image.
+# Linux direct boot uses the Linux-specific boot stub at this GPA.
+entry_point = 0x8000
+# The location of image: "memory" | "fs".
+image_location = "fs"
+# The file path of the kernel image.
+kernel_path = "/guest/linux/linux-qemu"
+# The load address of the kernel image.
+kernel_load_addr = 0x20_0000
+# Whether to enable BIOS boot flow.
+enable_bios = false
+# SVM phase-1 smoke keeps a dedicated command line so later stages can
+# adjust SVM bring-up independently from the VMX baseline.
+cmdline = "console=ttyS0 root=/dev/vda rw rootwait devtmpfs.mount=1 init=/sbin/getty acpi=off pci=conf1 pci=nomsi nox2apic tsc=unstable initcall_blacklist=ahci_pci_driver_init,i8042_init -- -n -l /bin/sh -L 115200 ttyS0 dumb"
+
+## The path of the disk image.
+# disk_path = ""
+
+# Memory regions with format (`base_paddr`, `size`, `flags`, `map_type`).
+# For `map_type`, 0 means `MAP_ALLOC`, 1 means `MAP_IDENTICAL`, 2 means `MAP_RESERVED`.
+memory_regions = [
+  [0x0000_0000, 0x0800_0000, 0x7, 1], # System RAM 128M MAP_IDENTICAL for DMA-capable passthrough
+  [0x0000_0000, 0x0010_0000, 0x7, 0], # Low boot scratch for real-mode stub and boot_params
+]
+
+#
+# Device specifications
+#
+[devices]
+# The interrupt mode.
+interrupt_mode = "passthrough"
+
+# Emu_devices.
+# Name Base-Ipa Ipa_len Alloc-Irq Emu-Type EmuConfig.
+emu_devices = [
+  ["x86-com1", 0x3f8, 0x8, 0x0, 0x2, []],
+  ["x86-ioapic", 0xfec0_0000, 0x1000, 0x0, 0x23, []],
+  ["x86-pit", 0x40, 0x22, 0x0, 0x24, []],
+]
+
+# Pass-through devices.
+# Name Base-Ipa Base-Pa Length Alloc-Irq.
+passthrough_devices = [
+  [
+    "HPET",
+    0xfed0_0000,
+    0xfed0_0000,
+    0x1000,
+    0x1,
+  ],
+]
+
+# Passthrough addresses.
+# Base-GPA  Length.
+passthrough_addresses = [
+  # QEMU q35 low MMIO window needed by PCI/virtio-blk probing.
+  [0xfe00_0000, 0x00c0_0000],
+  # Linux probes a q35/ICH system MMIO page at 0xfed8_03c0 after the PIT/HLT path is fixed.
+  [0xfed8_0000, 0x1000],
+]
+
+# Devices that are not desired to be passed through to the guest
+excluded_devices = []

os/axvisor/src/vmm/devices/x86.rs

@@ -13,7 +13,6 @@ const IOAPIC_VECTOR_END: usize = IOAPIC_VECTOR_BASE + IOAPIC_GSI_COUNT;
 
 const PIT_TIMER_GSI: usize = 0;
 const COM1_GSI: usize = 4;
-
 static IOAPIC_IRQ_FORWARDING_ENABLED: AtomicBool = AtomicBool::new(false);
 static IOAPIC_IRQ_HOOK_REGISTERED: AtomicBool = AtomicBool::new(false);
 static IOAPIC_IRQ_FORWARD_VM_ID: AtomicUsize = AtomicUsize::new(usize::MAX);

os/axvisor/src/vmm/vcpus.rs

@@ -467,6 +467,7 @@ fn vcpu_run() {
                     }
                 }
                 AxVCpuExitReason::PreemptionTimer => {
+                    super::timer::check_events();
                     #[cfg(target_arch = "x86_64")]
                     super::devices::x86::inject_due_pit_irq0(&vm, &vcpu);
                     #[cfg(target_arch = "x86_64")]

test-suit/axvisor/svm/qemu/build-x86_64-unknown-none.toml

@@ -8,4 +8,4 @@ features = [
 ]
 log = "Info"
 target = "x86_64-unknown-none"
-vm_configs = ["os/axvisor/configs/vms/nimbos-x86_64-qemu-smp1.toml"]
+vm_configs = ["os/axvisor/configs/vms/linux-x86_64-qemu-smp1-svm.toml"]

test-suit/axvisor/svm/qemu/smoke/qemu-x86_64.toml

@@ -1,28 +1,36 @@
 args = [
-  "-nographic",
+  "-nodefaults",
+  "-no-user-config",
+  "-display",
+  "none",
+  "-serial",
+  "stdio",
+  "-monitor",
+  "none",
   "-cpu",
   "host",
   "-machine",
-  "q35",
+  "q35,sata=off,smbus=off,i8042=off,usb=off,graphics=off",
   "-smp",
   "1",
   "-accel",
   "kvm",
   "-device",
-  "virtio-blk-pci,drive=disk0",
+  "virtio-blk-pci,drive=disk0,addr=03.0",
   "-drive",
   "id=disk0,if=none,format=raw,file=${workspace}/tmp/axbuild/rootfs/rootfs-x86_64-alpine.img",
   "-m",
-  "128M",
+  "512M",
 ]
+timeout = 180
 fail_regex = [
   "(?i)\\bpanic(?:ked)?\\b",
   "(?i)kernel panic",
   "(?i)login incorrect",
   "(?i)permission denied",
 ]
-success_regex = ["Hello world from user mode program!"]
-shell_prefix = ">>"
-shell_init_cmd = "hello_world"
+success_regex = ["(?m)^guest linux test pass!\\s*$"]
+shell_prefix = "~ #"
+shell_init_cmd = "pwd && echo 'guest linux test pass!'"
 to_bin = false
 uefi = false