Added support for Linux hosts

.gitignore

@@ -1,2 +1,6 @@
 # macOS
 .DS_Store
+
+# Linux
+*.o
+*.cmd

.travis.yml

@@ -13,6 +13,20 @@ matrix:
         - cd platforms/darwin
         - xcodebuild -configuration Debug -sdk macosx10.14
 
+    - name: "haxm-linux"
+      os: linux
+      dist: trusty
+      sudo: false
+      before_install:
+        - sudo apt-get update
+        - sudo apt-get install -y linux-headers-`uname -r`
+        - wget http://mirrors.kernel.org/ubuntu/pool/universe/n/nasm/nasm_2.13.02-0.1_amd64.deb
+        - sudo apt-get install -y dpkg
+        - sudo dpkg -i nasm_2.13.02-0.1_amd64.deb
+      script:
+        - cd platforms/linux
+        - make -j$(nproc)
+
   exclude: # TODO: Currently TravisCI does not support full VS/EWDK on Windows
     - name: "haxm-windows"
       os: windows

README.md

@@ -13,6 +13,7 @@ release, you can get it [here][github-haxm-latest-release].
 ## Usage
 
 Detailed instructions for building and testing HAXM can be found at:
+* [Manual for Linux](docs/manual-linux.md)
 * [Manual for macOS](docs/manual-macos.md)
 * [Manual for Windows](docs/manual-windows.md)
 

core/cpu.c

@@ -520,7 +520,7 @@ uint32_t load_vmcs(struct vcpu_t *vcpu, preempt_flag *flags)
     /* when wake up from sleep, we need the barrier, as vm operation
      * are not serialized instructions.
      */
-    smp_mb();
+    hax_smp_mb();
 
     cpu_data = current_cpu_data();
 

core/ept.c

@@ -328,7 +328,7 @@ static void invept_smpfunc(struct invept_bundle *bundle)
 {
     struct per_cpu_data *cpu_data;
 
-    smp_mb();
+    hax_smp_mb();
     cpu_data = current_cpu_data();
     cpu_data->invept_res = VMX_SUCCEED;
 
@@ -373,7 +373,7 @@ void invept(hax_vm_t *hax_vm, uint type)
 
     bundle.type = type;
     bundle.desc = &desc;
-    smp_call_function(&cpu_online_map, (void (*)(void *))invept_smpfunc,
+    hax_smp_call_function(&cpu_online_map, (void (*)(void *))invept_smpfunc,
                       &bundle);
 
     /*

core/hax.c

@@ -61,12 +61,12 @@ struct hax_t *hax;
 extern hax_atomic_t vmx_cpu_num, vmx_enabled_num;
 static void hax_enable_vmx(void)
 {
-    smp_call_function(&cpu_online_map, cpu_init_vmx, NULL);
+    hax_smp_call_function(&cpu_online_map, cpu_init_vmx, NULL);
 }
 
 static void hax_disable_vmx(void)
 {
-    smp_call_function(&cpu_online_map, cpu_exit_vmx, NULL);
+    hax_smp_call_function(&cpu_online_map, cpu_exit_vmx, NULL);
 }
 
 static void free_cpu_vmxon_region(void)
@@ -410,7 +410,7 @@ static void hax_pmu_init(void)
     int ref_cpu_id = -1;
 
     // Execute cpu_pmu_init() on each logical processor of the host CPU
-    smp_call_function(&cpu_online_map, cpu_pmu_init, NULL);
+    hax_smp_call_function(&cpu_online_map, cpu_pmu_init, NULL);
 
     // Find the common APM version supported by all host logical processors
     // TODO: Theoretically we should do the same for other APM parameters

core/ia32.c

@@ -70,7 +70,7 @@ void ia32_wrmsr(uint32_t reg, uint64_t val)
 #endif
 }
 
-uint64_t rdtsc(void)
+uint64_t ia32_rdtsc(void)
 {
 #ifdef HAX_ARCH_X86_32
     struct qword_val val = { 0 };

core/ia32_ops.asm

@@ -161,7 +161,7 @@ function __nmi, 0
     int 2h
     ret
 
-function __fls, 1
+function asm_fls, 1
     xor reg_ret_32, reg_ret_32
     bsr reg_ret_32, reg_arg1_32
     ret

core/include/cpu.h

@@ -108,12 +108,12 @@ struct per_cpu_data {
 
     /*
      * These fields are used to record the result of certain VMX instructions
-     * when they are used in a function wrapped by smp_call_function(). This is
+     * when they are used in a function wrapped by hax_smp_call_function(). This is
      * because it is not safe to call hax_error(), etc. (whose underlying
      * implementation may use a lock) from the wrapped function to log a
      * failure; doing so may cause a deadlock and thus a host reboot, especially
      * on macOS, where mp_rendezvous_no_intrs() (the legacy Darwin API used by
-     * HAXM to implement smp_call_function()) is known to be prone to deadlocks:
+     * HAXM to implement hax_smp_call_function()) is known to be prone to deadlocks:
      * https://lists.apple.com/archives/darwin-kernel/2006/Dec/msg00006.html
      */
     vmx_result_t    vmxon_res;

core/include/emulate_ops.h

@@ -39,7 +39,7 @@
                     (0 * FASTOP_ALIGN))
 
 /* Instruction handlers */
-typedef void(__cdecl em_handler_t)(void);
+typedef void(ASMCALL em_handler_t)(void);
 em_handler_t em_not;
 em_handler_t em_neg;
 em_handler_t em_inc;
@@ -72,7 +72,7 @@ em_handler_t em_bextr;
 em_handler_t em_andn;
 
 /* Dispatch handlers */
-void __cdecl fastop_dispatch(void *handler, uint64_t *dst,
+void ASMCALL fastop_dispatch(void *handler, uint64_t *dst,
                              uint64_t *src1, uint64_t *src2, uint64_t *flags);
 
 #endif /* HAX_CORE_EMULATE_OPS_H_ */

core/include/ia32.h

@@ -78,12 +78,12 @@ void ASMCALL asm_fxrstor(mword *addr);
 void ASMCALL asm_cpuid(union cpuid_args_t *state);
 
 void ASMCALL __nmi(void);
-uint32_t ASMCALL __fls(uint32_t bit32);
+uint32_t ASMCALL asm_fls(uint32_t bit32);
 
 uint64_t ia32_rdmsr(uint32_t reg);
 void ia32_wrmsr(uint32_t reg, uint64_t val);
 
-uint64_t rdtsc(void);
+uint64_t ia32_rdtsc(void);
 
 void fxinit(void);
 void fxsave(mword *addr);

core/include/vmx.h

@@ -681,7 +681,7 @@ void vmx_vmwrite(struct vcpu_t *vcpu, const char *name,
             vmwrite(vcpu, GUEST_##seg##_AR, tmp_ar);               \
         }
 
-#elif defined(HAX_PLATFORM_DARWIN)
+#else
 #define VMWRITE_SEG(vcpu, seg, val) ({                             \
             uint32_t tmp_ar = val.ar;                              \
             if (tmp_ar == 0)                                       \

core/intr_exc.c

@@ -48,7 +48,7 @@ uint32_t vcpu_get_pending_intrs(struct vcpu_t *vcpu)
 
     for (i = 7; i >= 0; i--) {
         if (intr_pending[i]) {
-            offset = __fls(intr_pending[i]);
+            offset = asm_fls(intr_pending[i]);
             break;
         }
     }

core/memory.c

@@ -342,7 +342,7 @@ int hax_vm_set_ram(struct vm_t *vm, struct hax_set_ram_info *info)
             hva = 0;
 #endif
 #endif
-            cur_va += page_size;
+            cur_va += HAX_PAGE_SIZE;
         }
 
         if (!hax_core_set_p2m(vm, gpfn, hpfn, hva, info->flags)) {

core/vcpu.c

@@ -565,7 +565,7 @@ static void vcpu_init(struct vcpu_t *vcpu)
 
     vcpu->ref_count = 1;
 
-    vcpu->tsc_offset = 0ULL - rdtsc();
+    vcpu->tsc_offset = 0ULL - ia32_rdtsc();
 
     // Prepare the vcpu state to Power-up
     state->_rflags = 2;
@@ -3247,7 +3247,7 @@ static int handle_msr_read(struct vcpu_t *vcpu, uint32_t msr, uint64_t *val)
 
     switch (msr) {
         case IA32_TSC: {
-            *val = vcpu->tsc_offset + rdtsc();
+            *val = vcpu->tsc_offset + ia32_rdtsc();
             break;
         }
         case IA32_FEATURE_CONTROL: {
@@ -3503,7 +3503,7 @@ static int handle_msr_write(struct vcpu_t *vcpu, uint32_t msr, uint64_t val)
 
     switch (msr) {
         case IA32_TSC: {
-            vcpu->tsc_offset = val - rdtsc();
+            vcpu->tsc_offset = val - ia32_rdtsc();
             if (vmx(vcpu, pcpu_ctls) & USE_TSC_OFFSETTING) {
                 vmwrite(vcpu, VMX_TSC_OFFSET, vcpu->tsc_offset);
             }
@@ -4160,9 +4160,9 @@ int vcpu_pause(struct vcpu_t *vcpu)
         return -1;
 
     vcpu->paused = 1;
-    smp_mb();
+    hax_smp_mb();
     if (vcpu->is_running) {
-        smp_call_function(&cpu_online_map, _vcpu_take_off, NULL);
+        hax_smp_call_function(&cpu_online_map, _vcpu_take_off, NULL);
     }
 
     return 0;
@@ -4171,15 +4171,15 @@ int vcpu_pause(struct vcpu_t *vcpu)
 int vcpu_takeoff(struct vcpu_t *vcpu)
 {
     int cpu_id;
-    cpumap_t targets;
+    hax_cpumap_t targets;
 
     // Don't change the sequence unless you are sure
     if (vcpu->is_running) {
         cpu_id = vcpu->cpu_id;
         assert(cpu_id != hax_cpuid());
         targets = cpu2cpumap(cpu_id);
         // If not considering Windows XP, definitely we don't need this
-        smp_call_function(&targets, _vcpu_take_off, NULL);
+        hax_smp_call_function(&targets, _vcpu_take_off, NULL);
     }
 
     return 0;

docs/manual-linux.md

@@ -0,0 +1,50 @@
+## Building for Linux
+
+**Disclaimer: Support for Linux is experimental.**
+
+### Prerequisites
+* Linux headers
+* NASM 2.11 or later
+
+### Build steps
+1. `cd platforms/linux/`
+1. `make`
+
+## Testing on Linux
+### System requirements
+Note that these are requirements for the _test_ environment, which does not
+have to be the same as the _build_ environment.
+
+1. Hardware requirements are the same as those for Windows.
+1. Linux 4.x or later.
+
+### Loading and unloading the kernel module
+To load the kernel module:
+1. Make sure no other HAXM kernel module is loaded. If the output of
+`lsmod | grep haxm` is not empty, you must unload the existing HAXM module
+first: `sudo make uninstall`.
+1. Run `sudo make install`.
+
+To unload the kernel module:
+1. Run `sudo make uninstall`.
+
+Additionally, if you want to use HAXM as a non-privileged user,
+you can enter the following command to make the current user
+part of the *haxm* group (requires logging out and back in!):
+
+```bash
+sudo adduser `id -un` haxm
+```
+
+Note that in recent Linux distributions, you might get a `sign-file` error
+since it kernel Makefiles will attempt to sign the kernel module with
+`certs/signing_key.pem`. Unless driver signature enforcement has been enabled,
+you can safely ignore this warning. Alternatively, you can follow
+[this guide][linux-module-signing] to self-sign your drivers.
+
+### Viewing logs
+On Linux, HAXM debug output goes to the system log database, and can be
+retrieved via `dmesg` (if supported, the `-w` flag will update the output).
+You might filter these entries via: `dmesg | grep haxm`.
+
+[linux-module-signing]: https://www.kernel.org/doc/html/v4.18/admin-guide/module-signing.html

include/darwin/hax_mac.h

@@ -205,4 +205,14 @@ static inline bool cpu_is_online(int cpu)
     return !!(((uint64_t)1 << cpu) & cpu_online_map);
 }
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern int cpu_number(void);
+
+#ifdef __cplusplus
+}
+#endif
+
 #endif  // HAX_DARWIN_HAX_MAC_H_

include/darwin/hax_types_mac.h

@@ -82,10 +82,10 @@ static hax_atomic_t hax_atomic_dec(hax_atomic_t *address)
 
 /*
  * According to kernel programming, the Atomic function is barrier
- * Although we can write a smp_mb from scrach, this simple one can resolve our
+ * Although we can write a hax_smp_mb from scrach, this simple one can resolve our
  * issue
  */
-static inline void smp_mb(void)
+static inline void hax_smp_mb(void)
 {
     SInt32 atom;
     OSAddAtomic(1, &atom);
@@ -132,10 +132,10 @@ typedef struct hax_kmap_phys {
 
 typedef ulong mword;
 typedef mword preempt_flag;
-typedef uint64_t cpumap_t;
+typedef uint64_t hax_cpumap_t;
 typedef uint64_t HAX_VADDR_T;
 
-static inline cpumap_t cpu2cpumap(int cpu)
+static inline hax_cpumap_t cpu2cpumap(int cpu)
 {
     return (0x1UL << cpu);
 }

include/hax.h

@@ -39,8 +39,6 @@
 // declaration
 struct vcpu_t;
 
-extern int hax_page_size;
-
 #define HAX_CUR_VERSION    0x0004
 #define HAX_COMPAT_VERSION 0x0001
 
@@ -207,7 +205,7 @@ void hax_set_page(phax_page page);
 
 static inline uint64_t hax_page2pa(phax_page page)
 {
-    return hax_page2pfn(page) << PAGE_SHIFT;
+    return hax_page2pfn(page) << HAX_PAGE_SHIFT;
 }
 
 #define hax_page_pa hax_page2pa
@@ -232,15 +230,15 @@ static inline unsigned char *hax_page_va(struct hax_page *page)
 #define HAX_MAX_CPUS (sizeof(uint64_t) * 8)
 
 /* Host SMP */
-extern cpumap_t cpu_online_map;
+extern hax_cpumap_t cpu_online_map;
 extern int max_cpus;
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-int smp_call_function(cpumap_t *cpus, void(*scfunc)(void *param), void *param);
-extern int cpu_number(void);
+int hax_smp_call_function(hax_cpumap_t *cpus, void(*scfunc)(void *param),
+                          void *param);
 
 uint32_t hax_cpuid(void);
 int proc_event_pending(struct vcpu_t *vcpu);
@@ -268,6 +266,9 @@ int hax_em64t_enabled(void);
 #ifdef HAX_PLATFORM_DARWIN
 #include "darwin/hax_mac.h"
 #endif
+#ifdef HAX_PLATFORM_LINUX
+#include "linux/hax_linux.h"
+#endif
 #ifdef HAX_PLATFORM_WINDOWS
 #include "windows/hax_windows.h"
 #endif

include/hax_interface.h

@@ -42,6 +42,9 @@
 #ifdef HAX_PLATFORM_DARWIN
 #include "darwin/hax_interface_mac.h"
 #endif
+#ifdef HAX_PLATFORM_LINUX
+#include "linux/hax_interface_linux.h"
+#endif
 #ifdef HAX_PLATFORM_WINDOWS
 #include "windows/hax_interface_windows.h"
 #endif