Support ESPs on ISO images

jmbaur · Jul 4, 2024 · e5f7552 · e5f7552
1 parent 3beac42
commit e5f7552
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Showing 2 changed files with 7 additions and 2 deletions.
diff --git a/src/boot/disk.zig b/src/boot/disk.zig
@@ -101,13 +101,16 @@ pub fn probe(
         for (mbr.partitions(), 1..) |part, mbr_partn| {
             const part_type = MbrPartitionType.fromValue(part.partType()) orelse continue;
 
-            if (part.isBootable() and
+            if ((part.isBootable() and
                 // BootLoaderSpec uses this partition type for MBR, see
                 // https://uapi-group.org/specifications/specs/boot_loader_specification/#the-partitionsl.
                 (part_type == .LinuxExtendedBoot or
                 // QEMU uses this partition type when using a FAT
                 // emulated drive with `-drive file=fat:rw:some/directory`.
-                part_type == .Fat16))
+                part_type == .Fat16)) or
+                // Many ISOs have this MBR table setup where the partition type
+                // is ESP and it is marked as non-bootable.
+                part_type == .EfiSystemPartition)
             {
                 break :b mbr_partn;
             }

diff --git a/src/disk/partition_table.zig b/src/disk/partition_table.zig
@@ -959,12 +959,14 @@ pub const MbrPartitionType = enum {
     Fat16,
     ProtectedMbr,
     LinuxExtendedBoot,
+    EfiSystemPartition,
 
     pub fn fromValue(val: u8) ?@This() {
         return switch (val) {
             0x06 => .Fat16,
             0xea => .LinuxExtendedBoot,
             0xee => .ProtectedMbr,
+            0xef => .EfiSystemPartition,
             else => return null,
         };
     }