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Description of problem:
Editing of long lines in PXE grub and similar environments is difficult to impossible

Version-Release number of selected component (if applicable):
seabios-0.6.1.2-19.el6.x86_64

How reproducible:
always

Steps to Reproduce:
1. edit very long kernel line in grub or pxe, use shortcuts like ctrl-w if possible
2.
3.
  
Actual results:
displayed text gets out of sync with what is actually is there

Expected results:
no such problems occur

Additional info:
see the screencast, note the weird things that happen with the cursor (arrow keys are only used for navigation in grub edit area)

given that I encountered this only in qemu VMs and in various versions of both gPXE in grub, I'm inclined to blame seabios. If it is not the case, please reassign

Created attachment 604974 [details]
screen recording

screen recording via cellphone, once in grub edit, only arrows and backspace changed cursor position...

More likely a vgabios bug.

Nevertheless I can't reproduce it.  Editing in grub works just fine for me (RHEL-6 guest, i.e. grub1).  Pressing Ctrl-W has no effect at all.  Details please.

(In reply to comment #2)
> More likely a vgabios bug.
> 
> Nevertheless I can't reproduce it.  Editing in grub works just fine for me
> (RHEL-6 guest, i.e. grub1).  Pressing Ctrl-W has no effect at all.  Details
> please.

I've sent you an email with instructions how to reproduce on my setup.

With the two attached binaries installed I see screen editing behavior becoming worse, on both virtual and real hardware.  So it is clearly pxelinux at fault here.

Running strings on the pxelinux binary says "PXELINUX 3.86 2010-04-01".  RHEL-6 ships 4.02 (this is what I'm running in my local setup).  I strongly recommend to update the pxelinux binaries on the boot server.