diff --git a/src/userland/mbr/main.c b/src/userland/mbr/main.c
index 7ae4f5e..280807c 100644
--- a/src/userland/mbr/main.c
+++ b/src/userland/mbr/main.c
@@ -15,7 +15,17 @@
     void *dataHere = requestMemory(1, NULL, firstSector);
     device->mbr = malloc(sizeof(ClassicMBR));
     memcpy(dataHere + 446, device->mbr, sizeof(ClassicMBR));
-    printf("MBR signature: 0x%x%x\n", device->mbr->signature[0], device->mbr->signature[1]);
+    if (device->mbr->signature[0] != 0x55 || device->mbr->signature[1] != 0xAA) {
+        printf("MBR signature did not match, got: 0x%x%x\n", device->mbr->signature[0], device->mbr->signature[1]);
+        return;
+    }
+    for (uint32_t entry = 0; entry < 4; entry++) {
+        PartitionTableEntry *partition = &device->mbr->entries[entry];
+        printf("partition %i: %i: start: %i, end: %i, active: %i\n", entry, partition->type, partition->lbaStart, partition->lbaStart + partition->sectorCount, partition->active);
+        if (partition->type == 0xEE) {
+            printf("partition %i is a GPT\n", entry);
+        }
+    }
 }
 
 int32_t main() {

diff --git a/src/userland/mbr/main.c b/src/userland/mbr/main.c
index 7ae4f5e..280807c 100644
--- a/src/userland/mbr/main.c
+++ b/src/userland/mbr/main.c
@@ -15,7 +15,17 @@
     void *dataHere = requestMemory(1, NULL, firstSector);
     device->mbr = malloc(sizeof(ClassicMBR));
     memcpy(dataHere + 446, device->mbr, sizeof(ClassicMBR));
-    printf("MBR signature: 0x%x%x\n", device->mbr->signature[0], device->mbr->signature[1]);
+    if (device->mbr->signature[0] != 0x55 || device->mbr->signature[1] != 0xAA) {
+        printf("MBR signature did not match, got: 0x%x%x\n", device->mbr->signature[0], device->mbr->signature[1]);
+        return;
+    }
+    for (uint32_t entry = 0; entry < 4; entry++) {
+        PartitionTableEntry *partition = &device->mbr->entries[entry];
+        printf("partition %i: %i: start: %i, end: %i, active: %i\n", entry, partition->type, partition->lbaStart, partition->lbaStart + partition->sectorCount, partition->active);
+        if (partition->type == 0xEE) {
+            printf("partition %i is a GPT\n", entry);
+        }
+    }
 }
 
 int32_t main() {
diff --git a/src/userland/usb/xhci/xhci.c b/src/userland/usb/xhci/xhci.c
index 35c1feb..1f9556c 100644
--- a/src/userland/usb/xhci/xhci.c
+++ b/src/userland/usb/xhci/xhci.c
@@ -5,6 +5,8 @@
 #include <hlib.h>
 #include <usb.h>
 
+// see https://www.intel.com/content/dam/www/public/us/en/documents/technical-specifications/extensible-host-controler-interface-usb-xhci.pdf
+
 XHCIInputContext *createInputContext(SlotXHCI *slot) {
     XHCIInputContext *inputContext = requestMemory(1, 0, 0);
     inputContext->inputControl.addContextFlags = 3;