Add config option to permit running option roms with bad checksums.HEADmaster

Based on a patch by: Stefan Reinauer <reinauer@google.com>

2 files changed, 13 insertions, 1 deletions

diff --git a/src/Kconfig b/src/Kconfig
index f064b27..6d55b23 100644
--- a/src/Kconfig
+++ b/src/Kconfig
@@ -250,6 +250,17 @@ menu "BIOS interfaces"
             Select this if option ROMs are already copied to
             0xc0000-0xf0000.  This must only be selected when using
             Bochs or QEMU versions older than 0.12.
+    config OPTIONROMS_CHECKSUM
+        depends on OPTIONROMS
+        bool "Require correct checksum on option ROMs"
+        default y
+        help
+            Option ROMs are required to have correct checksums.
+            However, some option ROMs in the wild don't correctly
+            follow the specifications and have bad checksums.
+            Say N here to allow SeaBIOS to execute them anyways.
+
+            If unsure, say Y.
     config PMM
         depends on OPTIONROMS
         bool "PMM interface"
diff --git a/src/optionroms.c b/src/optionroms.c
index a94b46c..37a4e6c 100644
--- a/src/optionroms.c
+++ b/src/optionroms.c
@@ -131,7 +131,8 @@ is_valid_rom(struct rom_header *rom)
     if (sum != 0) {
         dprintf(1, "Found option rom with bad checksum: loc=%p len=%d sum=%x\n"
                 , rom, len, sum);
-        return 0;
+        if (CONFIG_OPTIONROMS_CHECKSUM)
+            return 0;
     }
     return 1;
 }