[linux] Fix SIGILL on Jetson

fujitsu · Sep 10, 2023 · 3702f0d · 3702f0d
1 parent ffaa99b
commit 3702f0d
Showing 1 changed file with 21 additions and 1 deletion.
diff --git a/src/util_impl_linux.h b/src/util_impl_linux.h
@@ -73,6 +73,7 @@ class CpuInfoLinux : public CpuInfo {
 private:
   static constexpr int max_path_len = 1024;
   static constexpr int buf_size = 1024;
+  const char *path_midr_el1 = "/sys/devices/system/cpu/cpu0/regs/identification/midr_el1";
   const struct cacheInfo_v2_t cacheInfoDict[2] = {{/* A64FX */ XBYAK_AARCH64_MIDR_EL1(0x46, 0x1, 0xf, 0x1, 0x0),
                                                    {{/* L1 */ SeparateCache, {1024 * 64, 1024 * 64, 0}, {1, 1, 0}},
                                                     {/* L2 */ UnifiedCache, {0, 0, 1024 * 1024 * 8}, {0, 0, 12}},
@@ -428,7 +429,26 @@ class CpuInfoLinux : public CpuInfo {
     numCores_[0] = numCores_[1] = sysconf(_SC_NPROCESSORS_ONLN);
   }
 
-  void setSysRegVal() { XBYAK_AARCH64_READ_SYSREG(cacheInfo_.midr_el1, MIDR_EL1); }
+  void setSysRegVal() {
+    /* Some Linux does not permit to access MIDR_EL1 register
+       from user program. The register value is disclosed
+       in /sys/devices/system/cpu/cpu?/regs/identification/midr_el1 */
+    char buf[64];
+    char *stop;
+
+    FILE *file = fopen(path_midr_el1, "r");
+    if (file == nullptr) {
+      throw Error(ERR_INTERNAL);
+      return;
+    }
+
+    if (fread(buf, sizeof(char), 64, file) == 0) {
+      throw Error(ERR_INTERNAL);
+      return;
+    }
+
+    cacheInfo_.midr_el1 = strtoull(buf, &stop, 16);
+  }
 };
 
 #undef XBYAK_AARCH64_ERROR_