Chuck Ebbert wrote: >> Have fun, this code: >> - do not open the fast A20 gate before checking if the slow A20 gate is >> open or closed.
As does the current code; this is highly intentional behaviour since there are machines (in particular a whole series of machines made by Olivetti) which lock up if you do it differently. >> - uses in asm("") inputs which may or may not be set by the compiler in the >> stack, >> after modifying the stack pointer in the asm block: at least has_eflag() Point. "g" should be "ri". I will send a patch. >> - The VGA recalc has the same bug as the assembly version where a VGA write >> protected >> register is written (Overflow register) without setting the enable bit >> (see VGA docs). OK, that would be a bug ported directly from the assembly version. The fact that the bug can be seen now is part of why I did this work. Please feel free to submit a patch. >> - Does not save and restore %ds when printing a char on the screen (%ds is >> destroyed >> only when the content of the screen scroll - only for some video cards) %ds? Aren't you confusing it with the old bug which would destroy %bp? If you have any references to %ds being destroyed I would be very surprised. I can guarantee that very little if any assembly code I've ever seen that deals with INT 10h -- and I've seen a lot of it -- guards against %ds being randomly trashed. However, the trashing of %bp is a well-known bug (although only for machines older than the ones that can run Linux) -- the Interrupt List has: BUGS: some implementations (including the original IBM PC) have a bug which destroys BP >> - Has a "dn" for outl() which sliped in instead of "dN" That's a bug, although currently nonmanifest -- there are no users of outl() at the present. I will send a patch. >> and probably few other problems - just seen those by reading the patches >> (the asm("") >> are inlined in the C code - I find it more difficult to check). >> >> Also, I do not know if "m" is right in here: >> static inline u8 rdfs8(addr_t addr) >> { >> u8 v; >> asm("movb %%fs:%1,%0" : "=r" (v) : "m" (*(u8 *)addr)); >> return v; >> } The "m" is correct right there. >> I may repeat me, but to find these kind of problems, it is very nice to >> have an ELF >> file to do a readelf/objdump -D -m i8086 (even after final link). There is such a file (arch/i386/boot/setup.elf) which is retained, for exactly this reason. -hpa - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/