diff options
| -rw-r--r-- | pc-bios/s390-ccw/bootmap.c | 27 |
1 files changed, 23 insertions, 4 deletions
diff --git a/pc-bios/s390-ccw/bootmap.c b/pc-bios/s390-ccw/bootmap.c index 56411ab3b6..994e59c0b0 100644 --- a/pc-bios/s390-ccw/bootmap.c +++ b/pc-bios/s390-ccw/bootmap.c @@ -780,18 +780,37 @@ static void ipl_iso_el_torito(void) } } +/** + * Detect whether we're trying to boot from an .ISO image. + * These always have a signature string "CD001" at offset 0x8001. + */ +static bool has_iso_signature(void) +{ + int blksize = virtio_get_block_size(); + + if (!blksize || virtio_read(0x8000 / blksize, sec)) { + return false; + } + + return !memcmp("CD001", &sec[1], 5); +} + /*********************************************************************** * Bus specific IPL sequences */ static void zipl_load_vblk(void) { - if (virtio_guessed_disk_nature()) { - virtio_assume_iso9660(); + int blksize = virtio_get_block_size(); + + if (blksize == VIRTIO_ISO_BLOCK_SIZE || has_iso_signature()) { + if (blksize != VIRTIO_ISO_BLOCK_SIZE) { + virtio_assume_iso9660(); + } + ipl_iso_el_torito(); } - ipl_iso_el_torito(); - if (virtio_guessed_disk_nature()) { + if (blksize != VIRTIO_DASD_DEFAULT_BLOCK_SIZE) { sclp_print("Using guessed DASD geometry.\n"); virtio_assume_eckd(); } |