x86: doc: Document the -cdrom issues I ran into

Add a note about using -cdrom with QEMU.

Suggested-by: Bin Meng <bmeng@tinylab.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng@tinylab.org>

diff --git a/doc/board/emulation/qemu-x86.rst b/doc/board/emulation/qemu-x86.rst
index 15f56b6bc706c2d82ae8d74f6119352f82efbec8..c604e42990ed3757ecd99d377a5accc74559d262 100644 (file)
--- a/doc/board/emulation/qemu-x86.rst
+++ b/doc/board/emulation/qemu-x86.rst
@@ -193,6 +193,9 @@ Linux is selected from grub, e.g. with `debian-12.1.0-i386-netinst.iso`::
 The bochs video driver also seems to cause problems before the OS is able to
 show a display.
 
+The QEMU `-cdrom` option is intended to work with the original ISO-format
+images, not the recently invented ISOHybrid image.
+
 Finally, the use of `-M accel=kvm` is intended to use the native CPU's
 virtual-machine features to accelerate operation, but this causes U-Boot to hang
 when jumping 64-bit mode, at least on AMD machines. This may be a bug in U-Boot