Merge pull request #19 from rota1001/add-rv64-support

Add riscv64 support

Author: jserv

README.md

@@ -267,6 +267,7 @@ with
 
 - x86_64
 - aarch64
+- riscv64 (Only the trap mode and the seccomp mode are available)
 
 ## License
 

docs/architecture.md

@@ -174,6 +174,8 @@ host-kernel calls. `mmap` and `epoll_*` are deliberately excluded
 because they need W^X enforcement, shadow validation, or FD-table
 gating that the fast-path cannot perform.
 
+On **riscv64**, the rewrite mode is not available now.
+
 Each site is classified as WRAPPER (simple `syscall; ret` pattern,
 eligible for inline virtualized return: getpid=1, gettid=1, getppid=0)
 or COMPLEX (result consumed internally by helpers like `raise()` that

mk/toolchain.mk

@@ -29,6 +29,11 @@ CFLAGS  += -Wno-unused-parameter
 CFLAGS  += -Iinclude -Isrc
 LDFLAGS += -Wl,-z,noexecstack -Wl,-z,separate-code
 
+# Disable link relaxation of riscv64 architecture to prevent long link time
+ifeq ($(ARCH),riscv64)
+	LDFLAGS += -Wl,--no-relax
+endif
+
 # Build mode from Kconfig (fallback to BUILD= for unconfigured builds)
 ifeq ($(CONFIG_BUILD_RELEASE),y)
   CFLAGS  += -O2 -DNDEBUG

scripts/alpine-sha256.txt

@@ -1,2 +1,3 @@
 55ea3e5a7c2c35e6268c5dcbb8e45a9cd5b0e372e7b4e798499a526834f7ed90  alpine-minirootfs-3.21.0-x86_64.tar.gz
 f31202c4070c4ef7de9e157e1bd01cb4da3a2150035d74ea5372c5e86f1efac1  alpine-minirootfs-3.21.0-aarch64.tar.gz
+b2c5ed2be586aebd2da5dd13dbc96bc8cc41b72e517d0726dfbbb0a9810e66d6  alpine-minirootfs-3.21.0-riscv64.tar.gz

src/dispatch-misc.c

@@ -239,6 +239,8 @@ struct kbox_dispatch forward_uname(const struct kbox_syscall_request *req,
     snprintf(uts.machine, sizeof(uts.machine), "x86_64");
 #elif defined(__aarch64__)
     snprintf(uts.machine, sizeof(uts.machine), "aarch64");
+#elif (defined(__riscv) && __riscv_xlen == 64)
+    snprintf(uts.machine, sizeof(uts.machine), "riscv64");
 #else
     snprintf(uts.machine, sizeof(uts.machine), "unknown");
 #endif

src/elf.c

@@ -417,7 +417,7 @@ int kbox_build_elf_load_plan(const unsigned char *buf,
         p_memsz = read_le64(buf + off + P_MEMSZ_OFF);
         p_align = read_le64(buf + off + P_ALIGN_OFF);
 
-        if (p_filesz > p_memsz)
+        if (p_memsz && p_filesz > p_memsz)
             return -1;
 
         /* Validate that p_offset + p_filesz does not overflow.  We do

src/image.c

@@ -490,8 +490,8 @@ static const struct kbox_host_nrs *select_host_nrs(void)
 {
 #if defined(__x86_64__)
     return &HOST_NRS_X86_64;
-#elif defined(__aarch64__)
-    return &HOST_NRS_AARCH64;
+#elif defined(__aarch64__) || (defined(__riscv) && (__riscv_xlen == 64))
+    return &HOST_NRS_GENERIC;
 #else
     return NULL;
 #endif

src/loader-entry.c

@@ -17,6 +17,9 @@ static int machine_to_entry_arch(uint16_t machine,
     case 0xb7:
         *arch_out = KBOX_LOADER_ENTRY_ARCH_AARCH64;
         return 0;
+    case 0xf3:
+        *arch_out = KBOX_LOADER_ENTRY_ARCH_RISCV64;
+        return 0;
     default:
         return -1;
     }

src/loader-entry.h

@@ -9,6 +9,7 @@
 enum kbox_loader_entry_arch {
     KBOX_LOADER_ENTRY_ARCH_X86_64,
     KBOX_LOADER_ENTRY_ARCH_AARCH64,
+    KBOX_LOADER_ENTRY_ARCH_RISCV64
 };
 
 struct kbox_loader_entry_state {

src/loader-transfer.c

@@ -89,6 +89,24 @@ kbox_loader_transfer_to_guest(const struct kbox_loader_transfer_state *state)
         : "r"(sp), "r"(x0), "r"(x1), "r"(x2), "r"(x3), "r"(x4), "r"(x5),
           "r"(x16)
         : "memory");
+#elif defined(__riscv) && (__riscv_xlen == 64)
+    if (state->arch != KBOX_LOADER_ENTRY_ARCH_RISCV64)
+        __builtin_trap();
+    register uint64_t a0 __asm__("a0") = state->regs[0];
+    register uint64_t a1 __asm__("a1") = state->regs[1];
+    register uint64_t a2 __asm__("a2") = state->regs[2];
+    register uint64_t a3 __asm__("a3") = state->regs[3];
+    register uint64_t a4 __asm__("a4") = state->regs[4];
+    register uint64_t a5 __asm__("a5") = state->regs[5];
+    register uint64_t t0 __asm__("t0") = state->pc;
+    uint64_t sp = state->sp;
+
+    __asm__ volatile(
+        "mv sp, %0\n\t"
+        "jr t0\n\t"
+        :
+        : "r"(sp), "r"(a0), "r"(a1), "r"(a2), "r"(a3), "r"(a4), "r"(a5), "r"(t0)
+        : "memory");
 #else
     (void) state;
     __builtin_trap();