what is the fatest way to trigger ring 0 code?

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jtlb
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what is the fatest way to trigger ring 0 code?

Post by jtlb »

I am looking for the fastest method for user code to trigger supervisor code. From what i read i think it is the syenter/sysexit and syscall/sysret pairsbut i'm not sure.
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AJ
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Re: what is the fatest way to trigger ring 0 code?

Post by AJ »

Moved topic and I believe you are correct - it's sysenter/exit and syscall/ret.

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Re: what is the fatest way to trigger ring 0 code?

Post by Combuster »

At least, they were designed to be faster than conventional methods. The problem is, they aren't supported on all systems while far calls (brendan's next favorite) are.
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jtlb
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Re: what is the fatest way to trigger ring 0 code?

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Combuster wrote:At least, they were designed to be faster than conventional methods. The problem is, they aren't supported on all systems while far calls (brendan's next favorite) are.
Are far calls, calls using a special gate in the GDT? And how slower is it?
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Re: what is the fatest way to trigger ring 0 code?

Post by Combuster »

"Certainly avoid yourself. He is a newbie and might not realize it. You'll hate his code deeply a few years down the road." - Sortie
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