r/coreboot

Image 1 — I found the hidden Advanced BIOS menu
Image 2 — I found the hidden Advanced BIOS menu
▲ 103 r/coreboot+12 crossposts

I found the hidden Advanced BIOS menu

I have been reverse-engineering the InsydeH2O firmware used by the Lenovo IdeaPad Gaming 3 15ARH05 (82EY / IP3GAMING-15ARH).

The project started because this model exposes only a very limited BIOS interface, while common unlock sequences such as Fn+R+N do not appear to work reliably on this generation.

So far, I have:

  • extracted Lenovo’s official FCCN21WW Windows update package;
  • recovered the complete 16 MiB update ROM;
  • parsed its AMD PSP directory;
  • decompressed and executed the x86 reset-stage image;
  • traced its reset loop under QEMU;
  • extracted the Setup Utility and reconstructed its IFR;
  • confirmed the existence of a separate hidden Advanced form set;
  • recovered its GUID, variable stores, offsets and option inventory;
  • tested an experimental SREP runtime patch without permanently modifying the firmware.

The hidden menu contains controls for:

  • PCIe GPP and power policies;
  • SATA/AHCI and RAID configuration;
  • TPM and fTPM;
  • USB controllers and individual ports;
  • ACPI features;
  • SVM, SVM Lock and SMM Code Lock;
  • DASH and AMD remote KVM;
  • Above 4 GB MMIO.

One particularly interesting result is that the Advanced form set is not surrounded by a top-level IFR SuppressIf condition. My current hypothesis is that Lenovo/Insyde hides it through a visibility table or registration logic inside H2OFormBrowserDxe, rather than through a simple “unlock” setup variable.

I also recovered this form-set GUID:

C6D4769E-7F48-4D2A-98E9-87ADCCF35CCC

However, the runtime SREP patch has not exposed the menu yet. The laptop currently runs FCCN19WW, while the analyzed update is FCCN21WW, so differences in modules, patterns or variable semantics may explain the failure.

The repository documents the full process, hashes, extraction commands, QEMU findings, IFR inventory, experimental SREP configuration and suggested next steps:

https://github.com/root-hunter/lenovo_bios

Update: the hidden Advanced BIOS menu has now been successfully unlocked on the test machine using SREP. This is a runtime unlock and does not require flashing a modified BIOS image.

The method remains experimental and model/firmware-specific. Hidden settings can still cause a brick, boot failure or no-display condition, so do not change unfamiliar options without a verified SPI backup and recovery plan.

I would especially appreciate help from anyone who:

  • owns the same 15ARH05 / 82EY model and can reproduce the unlock;
  • can test it on other FCCN firmware versions;
  • has experience with InsydeH2O, SREP or H2OFormBrowserDxe;
  • can help validate and document the exposed settings safely.

Issues, corrections and reproducible test results are welcome.

u/roothunter-dev — 19 hours ago
▲ 17 r/coreboot+2 crossposts

An Open Letter to AMI Firmware Engineers: It’s Time to Bring Screen Reader Accessibility to Aptio UEFI BIOS

To the firmware engineering teams at American Megatrends (AMI) and other major UEFI developers:Millions of computers worldwide rely on AMI**'s Aptio firmware to boot and manage hardware. Yet, entering the pre-OS environment remains a complete blackout for blind and visually impaired users who rely on screen readers like NVDA.We are fully capable of managing our devices, configuring systems, and performing maintenance. What we lack is not technical skill, but basic accessibility engineering in the BIOS. Relying exclusively on graphical, visual-only interfaces creates an unnecessary barrier and locks blind users out of fundamental hardware controlWith modern UEFI frameworks, it is entirely feasible to integrate lightweight text-to-speech or basic audio/screen-reader hooks into the pre-boot environment. We urge AMI engineers and firmware developers to prioritize accessibility in future Aptio releases. Technology should empower everyone equally, starting from the moment the power button is pressed."**

reddit.com
u/obaida2026 — 1 day ago

HP ProBook 6460b full Windows support

So I have an HP ProBook 6460b and I can already run Linux perfectly with coreboot. I originally installed coreboot because I wanted to be able to run an i7-3840qm, along with circumventing the WiFi card whitelist (currently I have a BE200 installed too).

To use coreboot, which has no preset for the 6460b, I selected the EliteBook 8460p under the assumption that the two systems are close enough.

Obviously, I know it's frowned upon to run Windows with coreboot, and I already have got it almost totally working with SeaBIOS. I used the option rom v2170 instead of libgfxinit, and even ripped an ME 8 blob from a ProBook 6470b BIOS, which surprisingly still POSTed.

Anyway, the main issue I'm having currently is that in Windows 10, the battery icon reports that there are no batteries physically installed. This is not the case in Linux; it has no trouble reading the battery meter. I want to at least have the ability to run Windows 7, hence my choice of SeaBIOS, and currently the installer does not boot (it gets stuck on the glowy logo). In Windows 10, I have yet to get power management working correctly either; the system gets stuck when attempting to shutdown, sleep, or reboot, and nothing happens.

What do I need to do to fix my install to finally get it working fully?

reddit.com
u/ProGamer154 — 1 day ago

Buying a motherboard with Coreboot

I am looking to build a new PC and want Coreboot installed. However, all I can find online are vendors selling prebuilt machines with Coreboot, such as System76, in which case I am paying for components I don't need. From what I read online, it sounds like building Coreboot for a modern motherboard is unreasonably hard and not practical. I am looking specifically for a mobo that supports ECC memory, and also not Intel, which further narrows my options. Are there any options out there that fit the bill?

reddit.com
u/tic-tac135 — 5 days ago

Building coreboot on Gentoo

Hey there!

I've been trying to build coreboot on my Gentoo installation, but have been running into various issues.

I made sure that my gcc compile has ada support (for gnat), and that I have (roughly) the dependencies listed as requirements for Fedora.

I believe that I have gnat through my gcc install, but I don't have any packages/dependencies for gnat. gnat does, however, seem to be a viable command in CLI.

Despite this, I've still been hitting into some issues and can't seem to compile any final images.

Things like ifdtool and deguard work, though, even when compiled on my system. I compared sha256 sums from progress made on my current system with identical work done on a Debian system, and the sums match, so it seems that it can build most tools properly, and it just can't install.

I'm currently recloning coreboot's repo and building every possible cpu arch/toolchain (I only build i386 as instructed beforehand) just to be thorough on my end. If it works, I'll update the post.

Asides that, is there any known issues with Gentoo that would force me to use a VM to build in, or are there any necessary workarounds needed to build with Gentoo?

Running stable branch, excluding packages that only have an ~amd64 release.

reddit.com
u/LowKeyBrit36 — 5 days ago

What's the process to update libreboot on a T420 thinkpad?

I have libreboot pre-installed on this Thinkpad T420, but I am unsure of how to update the installation since the T420 has the BUP and ROMP blobs. Are these distributed in the release ROM?

reddit.com
u/Tricky-Engineer-9755 — 6 days ago

Tri booting

Is it possible to triple boot Chrome OS, then two Linux distros? I couldn’t find anything online on if and how you can do it. Let me know if you need any more information from me.

Edit: Sorry about posting here, wasn’t sure where to post

reddit.com
u/Ok_Royal7459 — 9 days ago