multiboot2: ignore unsupported tags if they are marked optional
diff --git a/common/protos/multiboot2.c b/common/protos/multiboot2.c
index fe15059f..d6791613 100644
--- a/common/protos/multiboot2.c
+++ b/common/protos/multiboot2.c
@@ -119,12 +119,12 @@ noreturn void multiboot2_load(char *config, char* cmdline) {
for (struct multiboot_header_tag *tag = (struct multiboot_header_tag*)(header + 1); // header + 1 to skip the header struct.
tag < (struct multiboot_header_tag *)((uintptr_t)header + header->header_length) && tag->type != MULTIBOOT_HEADER_TAG_END;
tag = (struct multiboot_header_tag *)((uintptr_t)tag + ALIGN_UP(tag->size, MULTIBOOT_TAG_ALIGN))) {
+ bool is_required = !(tag->flags & MULTIBOOT_HEADER_TAG_OPTIONAL);
switch (tag->type) {
case MULTIBOOT_HEADER_TAG_INFORMATION_REQUEST: {
// Iterate the requests and check if they are supported by or not.
struct multiboot_header_tag_information_request *request = (void *)tag;
uint32_t size = (request->size - sizeof(struct multiboot_header_tag_information_request)) / sizeof(uint32_t);
- bool is_required = !(request->flags & MULTIBOOT_HEADER_TAG_OPTIONAL);
for (uint32_t i = 0; i < size; i++) {
uint32_t r = request->requests[i];
@@ -192,7 +192,9 @@ noreturn void multiboot2_load(char *config, char* cmdline) {
has_reloc_header = true;
break;
- default: panic(true, "multiboot2: Unknown header tag type: %u\n", tag->type);
+ default:
+ if (is_required)
+ panic(true, "multiboot2: Unknown header tag type: %u\n", tag->type);
}
}
