[solved]why syser lose one gdt entry...

[gxm]

hi guys...i have some questions with GDT and syser debugger...
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i>photo as follows.

the two descriptors between 50h---60h lose.
ii>
it is very strange that...in the 3f030h offset...
*0*PS:gdtr=8003f000;i use the page instruction to convert it to physcal address[3f000].BUT I DO NOT KNOW IS THIS RIGHT...BECAUSE I DO NOT KNOW WHICH KIND OF ADDRESS OF GDTR IS???VIRTUAL ADDRESS OF PHYSICAL ADDRESS;I DO NOT KNOW... :P*0*
*1*now i got to know that the gdtr provide a linear address,and the response physical address is truly 3f000.Though in the syser command help manaul said "page xxx means convert virtual address to physical address",but it work fine with this linear address... :8),wondering why it will works fine.is the PA of VA 8003f000 also 3f000???*1*

*1*and another question,since the descriptor is 8 byte long,so the selector of  the GDT table  in Syser should a multiple of 8, anyway,so why there is one 23h...etc....*1*
Anyway if i got the right physical address,then
we can get one descriptor--->ffc093dff0000001h.
base address:ffdff000;limit:00001;then why syser said it was 1|ff|ffh.
and isn't the descriptor limitation should only be 20 bits...so what the hell does ff|ff|ff|ff|h do???[in the above entries]
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by the way why the descriptor limitation should be 20 bits???
*1*i am a bit afraid that here isn't a good place to talk this kind of question,since there are so many os develop forum,and even the support forum of syser...but i posted it here the first of all....and if it is not sutiable to talk this kind of question here since there is not so much link bettween masm32 and GDT/os dev/etc...please let me know...i'll remove it rightway...thx in advance....*1*.
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regs
gxm

[gxm]

*2*finally i managed to know that the PA of VA 8003f000 and PA of LA 8003f000 was the same,because the Page Directory Entry-->Page Entry-->Page Base is 0...*2*

[gxm]

*3*softice did the same thing as syser*3*

[gxm]

thx to xIkUg.i finally got the answer.
silly question.
i mix up the segment selector with gdt offset(they resemble at the first and end :wallbash:
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anyway thx for your time...