Bail to interpreted mode on self-modified code

[donno2048]

As mentioned in #1561, self-modified code that isn't being jumped into isn't being handled (for the same page it's being only logged and for other reachable pages where if we don't jump into it but rather read into it "sequentially" it's not being handled at all).

Should maybe just add a "was overwritten" flag to any block, and if the write was to a an address between instruction_pointer and the end of the current block bail, otherwise set the relevant block's flag, and whenever transitioning between blocks, bail if the flag is set..?

[copy]

Should maybe just add a "was overwritten" flag to any block, and if the write was to a an address between instruction_pointer and the end of the current block bail, otherwise set the relevant block's flag, and whenever transitioning between blocks, bail if the flag is set..?

I think it would be both simpler and more performant to add a new bail-out path from safe_write_slow_jit:

• It already has a path to bail out on pagefaults and to delete generated jit code. The bail out path needs to be changed to "do nothing" (continue executing at the next instruction)
• I don't think the SMC check in safe_write_slow_jit is complete: It needs to be based on physical addresses (it would be hit anyway, because all writes to a page that contains code go into the slow path)

Just as a heads-up, I probably won't have time to review this.

[donno2048]

Just as a heads-up, I probably won't have time to review this.

I don't have much time for it either currently, so might work on it next month.

[copy]

FYI, I will have a fix for this

[donno2048]

Awesome!