[syslinux] Read disk not working in 3.35+

[H. Peter Anvin]

Ram Yalamanchili wrote:
> Thanks for the fix. I'm ok with waiting to 3.40.
> 
> Another question would be, would you want to provide a library
> function which can allocate the memory in the fashion 0x19h needs it:
> aligned and not crossing 64k boundaries?
> 
> I am not sure if static allocation of a variable and using it's
> address will work since it might be above the 16bit address range.

Not just might, but *will* be.

> eg: char sectorBuf[64*1024*2] and getting an address within it which
> is aligning to 64k.
> 
> If you dont think the lib function is a good idea, what options do i
> have other than using the bounce buffer?

None.  The bounce buffer is actually by definition *all* the memory 
below 1 MB available to the COM32 program.

Doing up a set of library functions for the COM32 API is something that 
is somewhere on the TODO list, but I don't really know how far down. 
This is something that would be an excellent volunteer project.

	-hpa