Pavel Machek wrote:
+ .code16 + .text + .globl intcall + .type intcall, @function +intcall: + /* Self-modify the INT instruction. Ugly, but works. */ + cmpb %al, 3f + je 1f + movb %al, 3f + jmp 1f /* Synchronize pipeline */ +1:There are various CPU bugs with self-modifying code, but I guess we are not using it heavily enough. Also we are single-threaded so that should be ok. Pavel
This case is extremely straightforward, so I'm not worried about it. The final JMP is actually not required (there is a LOOP instruction between the modify and the invocation point) but is there for extra safety.
FWIW, we already do SMC during the transfer to protected mode (pmjump.S), and hopefully got the issues worked out there.
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