Hi Steve, Here's an updated patch to enable serial console in grub when using debian-installer on an EFI based system. Sorry it took longer than anticipated - got pulled into some other things.
The patch has been updated based on your feedback (and some experimentation). Notably, this version does not touch other configuration but uses the "--append" option of terminal_output/terminal_input to add serial port support. I've tested this on Qemu and it solves the problem I was hitting. If the changes look OK, do consider including the patch to get wider coverage / testing in more scenarios. Thanks, Punit
0001-x86-grub-efi-Enable-serial-console.patch
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