On Mon, Jan 12, 2015 at 09:59:49AM -0600, Richard Laager wrote:
On Mon, 2015-01-12 at 10:32 -0500, Kevin O'Connor wrote:
Interesting. Does your original business app then also work with CONFIG_VGA_ALLOCATE_EXTRA_STACK disabled?
Yes. I couldn't be sure if I tested before, since I didn't write it down. But I just tested now.
Obviously this extra stack feature exists for a reason. What are the implications of turning it off?
There is a high-level description of the feature at:
http://seabios.org/Execution_and_code_flow#Extra_16bit_stack
Basically, SeaVGABIOS is capable of allocating space for an internal stack at startup and then switching to that stack on each vgabios call so that it can work with some really old DOS-era programs that used ridiculously small stacks. If things work for you with the feature off, then it's not a problem to leave it off.
I'm trying to reproduce the fault with skifree locally. If I can't, it would be helpful if you can run some additional tests and grab some additional logs. I'll let you know.
-Kevin