Messages in this thread | | | From | shaggy@jade ... | Subject | Call Gates | Date | Fri, 20 Jun 1997 07:39:20 -0400 (EDT) |
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Hi there,
I am trying to understand how call gates work and as usual the Intel documentation sucks. Can someone tell me or point me to a reference that says EXACTLY what happens when a call gate is used, eg: from the moment the CALL 0007:00000000 (for example) is executed to the time it is handled. I was looking through another OS's source code and they use 0x07 as the designated call gate for system calls, however when looking at how they initted the LDT, the table entry was the first line in the descriptor array initialization. Is 0x07 an index into the LDT or is it some other number (I dont think it is realted to the type, though). I would think that once executed, the CALL makes the processor goto LDT[7] and pull out that call gate then do the funky address computation and stack change and do the other code...
-S
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