On Tue, Jan 06, 2026 at 12:49:01AM +0000, Alexander Graf via SeaBIOS wrote: > Implement catch-all mechanism to handle invalid boot loaders that execute > random instructions and reach the VGA hole at 0xa0000, which would lead to > VM crashes with KVM_INTERNAL_ERROR. > > When a BIOS boot loader gets corrupted, it can end up jumping across > address space and execute stray code. The typical symptom of that is > that it executes 0x0 (addw) instructions until the code reaches an MMIO > region, such as the VGA window. When running in KVM, attempting to > execute code from the MMIO window results in KVM_INTERNAL_ERROR exits > which crash the VM. > > To prevent VM crashes before we reach such an MMIO window, introduce an > internal int 0xf0 handler and call it at strategic locations that should > never get executed in the first place. When we now have stray code > executing, these int calls cause an emergency print of "BIOS failed to > boot volume" and cleanly shut down the machine.
Does it make sense to include a hint in the error message that a corrupted disk / boot loader might be the root cause? I've never seen that, care to share some real world examples where this actually happens? take care, Gerd _______________________________________________ SeaBIOS mailing list -- [email protected] To unsubscribe send an email to [email protected]
