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read/only pages not protected in DosBox?

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First post, by japheth

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Hello,

I'm using DosBox for testing some protected-mode apps and just discovered that pages marked as readonly can be written to from ring 3 protected mode, which on a real cpu is not possible.

Is this by design or is this a bug? I can imagine that some dos-extender apps may rely on getting page faults if someone tries to write such pages.

Regards

Japheth

Reply 1 of 6, by h-a-l-9000

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all cores?

1+1=10

Reply 2 of 6, by wd

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dosbox doesn't care about page protection (only for the
first access to a non-present page), doesn't care about
segment limits etc. all because those would greatly
reduce the speed.

Reply 3 of 6, by japheth

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> all because those would greatly reduce the speed.

that's understandable, but at least optionally (possibly not at runtime if it is a speed issue, but at compiletime) it would be good to have these things included.

Reply 4 of 6, by wd

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That'd require a lot of changes, so i doubt anybody will do this,
yet maybe somebody has a lot of time...

Reply 5 of 6, by Lofty

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It's a shame the PC is such a complicated machine to emulate fully...

Reply 6 of 6, by wd

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BOCHS does a good job, so if something like that is really needed
there's always the bochs- and others option.

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