:: commit 003a45c8056cd69f072227af7320a96816fb6e68

diff --git a/common/drivers/disk.s2.c b/common/drivers/disk.s2.c
index be838689..188f5ff0 100644
--- a/common/drivers/disk.s2.c
+++ b/common/drivers/disk.s2.c
@@ -126,6 +126,39 @@ int disk_read_sectors(struct volume *volume, void *buf, uint64_t block, size_t c
     return DISK_SUCCESS;
 }
 
+static int disk_write_sectors(struct volume *volume, void *buf, uint64_t block, size_t count) {
+    struct dap dap = {0};
+
+    if (count * volume->sector_size > XFER_BUF_SIZE)
+        panic(false, "XFER");
+
+    if (xfer_buf == NULL)
+        xfer_buf = conv_mem_alloc(XFER_BUF_SIZE);
+
+    dap.size    = 16;
+    dap.count   = count;
+    dap.segment = rm_seg(xfer_buf);
+    dap.offset  = rm_off(xfer_buf);
+    dap.lba     = block;
+
+    struct rm_regs r = {0};
+    r.eax = 0x4301;
+    r.edx = volume->drive;
+    r.esi = (uint32_t)rm_off(&dap);
+    r.ds  = rm_seg(&dap);
+
+    if (buf != NULL)
+        memcpy(xfer_buf, buf, count * volume->sector_size);
+
+    rm_int(0x13, &r, &r);
+
+    if (r.eflags & EFLAGS_CF) {
+        return DISK_FAILURE;
+    }
+
+    return DISK_SUCCESS;
+}
+
 static bool detect_sector_size(struct volume *volume) {
     struct dap dap = {0};
 
@@ -226,14 +259,14 @@ void disk_create_index(void) {
             continue;
         }
 
-        if (drive_params.info_flags & (1 << 2) && drive > 0x8f) {
-            // The medium could not be present (e.g.: CD-ROMs)
-            // Do a test run to see if we can actually read it
-            if (disk_read_sectors(block, NULL, 0, 1) != DISK_SUCCESS) {
-                continue;
-            }
+        if (disk_read_sectors(block, xfer_buf, 0, 1) != DISK_SUCCESS) {
+            continue;
+        }
+
+        block->is_optical = disk_write_sectors(block, xfer_buf, 0, 1) != DISK_SUCCESS;
+
+        if (block->is_optical) {
             block->index = optical_indices++;
-            block->is_optical = true;
         } else {
             block->index = hdd_indices++;
         }