Made the bootloader search for both kernel_x86 and kernel_x86_64 when built for x86 or x86_64.

src/system/boot/loader/Jamfile

@@ -38,6 +38,18 @@ UsePrivateHeaders shared storage ;
 		case "x86" :
 		{
 			defines +=
+				ALTERNATE_BOOT_ARCH=\\\"x86_64\\\"
+
+				BOOT_SUPPORT_PARTITION_EFI
+
+				#BOOT_SUPPORT_FILE_SYSTEM_FAT
+			;
+		}
+		case "x86_64" :
+		{
+			defines +=
+				ALTERNATE_BOOT_ARCH=\\\"x86\\\"
+
 				BOOT_SUPPORT_PARTITION_EFI
 
 				#BOOT_SUPPORT_FILE_SYSTEM_FAT

src/system/boot/loader/loader.cpp

@@ -24,11 +24,24 @@
 #	error BOOT_ARCH has to be defined to differentiate the kernel per platform
 #endif
 
-#define KERNEL_IMAGE	"kernel_" BOOT_ARCH
+#define KERNEL_IMAGE			"kernel_" BOOT_ARCH
-#define KERNEL_PATH		"system/" KERNEL_IMAGE
+#define KERNEL_PATH				"system/" KERNEL_IMAGE
+
+#ifdef ALTERNATE_BOOT_ARCH
+# define ALTERNATE_KERNEL_IMAGE	"kernel_" ALTERNATE_BOOT_ARCH
+# define ALTERNATE_KERNEL_PATH	"system/" ALTERNATE_KERNEL_IMAGE
+#endif
 
 
-static const char *sPaths[] = {
+static const char *sKernelPaths[][2] = {
+	{ KERNEL_PATH, KERNEL_IMAGE },
+#ifdef ALTERNATE_BOOT_ARCH
+	{ ALTERNATE_KERNEL_PATH, ALTERNATE_KERNEL_IMAGE },
+#endif
+	{ NULL, NULL },
+};
+
+static const char *sAddonPaths[] = {
 	kVolumeLocalSystemKernelAddonsDirectory,
 	kVolumeLocalCommonKernelAddonsDirectory,
 	kVolumeLocalUserKernelAddonsDirectory,
@@ -36,6 +49,22 @@ static const char *sPaths[] = {
 };
 
 
+static int
+find_kernel(Directory *volume, const char **name = NULL)
+{
+	for (int32 i = 0; sKernelPaths[i][0] != NULL; i++) {
+		int fd = open_from(volume, sKernelPaths[i][0], O_RDONLY);
+		if (fd >= 0) {
+			if (name)
+				*name = sKernelPaths[i][1];
+
+			return fd;
+		}
+	}
+
+	return B_ENTRY_NOT_FOUND;
+}
+
 bool
 is_bootable(Directory *volume)
 {
@@ -43,7 +72,7 @@ is_bootable(Directory *volume)
 		return false;
 
 	// check for the existance of a kernel (for our platform)
-	int fd = open_from(volume, KERNEL_PATH, O_RDONLY);
+	int fd = find_kernel(volume);
 	if (fd < B_OK)
 		return false;
 
@@ -56,11 +85,12 @@ is_bootable(Directory *volume)
 status_t
 load_kernel(stage2_args *args, Directory *volume)
 {
-	int fd = open_from(volume, KERNEL_PATH, O_RDONLY);
+	const char *name;
+	int fd = find_kernel(volume, &name);
 	if (fd < B_OK)
 		return fd;
 
-	dprintf("load kernel...\n");
+	dprintf("load kernel %s...\n", name);
 
 	elf_init();
 	status_t status = elf_load_image(fd, &gKernelArgs.kernel_image);
@@ -78,7 +108,7 @@ load_kernel(stage2_args *args, Directory *volume)
 		return status;
 	}
 
-	gKernelArgs.kernel_image.name = kernel_args_strdup(KERNEL_IMAGE);
+	gKernelArgs.kernel_image.name = kernel_args_strdup(name);
 
 	return B_OK;
 }
@@ -129,9 +159,9 @@ load_module(Directory *volume, const char *name)
 	if (strlcpy(moduleName, name, sizeof(moduleName)) > sizeof(moduleName))
 		return B_NAME_TOO_LONG;
 
-	for (int32 i = 0; sPaths[i]; i++) {
+	for (int32 i = 0; sAddonPaths[i]; i++) {
 		// get base path
-		int baseFD = open_from(volume, sPaths[i], O_RDONLY);
+		int baseFD = open_from(volume, sAddonPaths[i], O_RDONLY);
 		if (baseFD < B_OK)
 			continue;
 
@@ -179,9 +209,9 @@ load_modules(stage2_args *args, Directory *volume)
 	// ToDo: this should be mostly replaced by a hardware oriented detection mechanism
 
 	int32 i = 0;
-	for (; sPaths[i]; i++) {
+	for (; sAddonPaths[i]; i++) {
 		char path[B_FILE_NAME_LENGTH];
-		snprintf(path, sizeof(path), "%s/boot", sPaths[i]);
+		snprintf(path, sizeof(path), "%s/boot", sAddonPaths[i]);
 
 		if (load_modules_from(volume, path) != B_OK)
 			failed++;
@@ -195,7 +225,7 @@ load_modules(stage2_args *args, Directory *volume)
 
 		for (int32 i = 0; paths[i]; i++) {
 			char path[B_FILE_NAME_LENGTH];
-			snprintf(path, sizeof(path), "%s/%s", sPaths[0], paths[i]);
+			snprintf(path, sizeof(path), "%s/%s", sAddonPaths[0], paths[i]);
 			load_modules_from(volume, path);
 		}
 	}
@@ -220,7 +250,7 @@ load_modules(stage2_args *args, Directory *volume)
 		//	as this piece will survive a more intelligent module
 		//	loading approach...
 		char path[B_FILE_NAME_LENGTH];
-		snprintf(path, sizeof(path), "%s/%s", sPaths[0], "file_systems");
+		snprintf(path, sizeof(path), "%s/%s", sAddonPaths[0], "file_systems");
 		load_modules_from(volume, path);
 	}