On Sun, Nov 07, 2004 at 00:14:25 +0900, aq wrote: > I think there is one question of Kannan unanswered: CS has attribute > of "READ-ONLY", and DS has attribute of "READ-WRITE". And we all know > that CS and DS point to the same address range (they have the same > base address of 0, and same size of 4GB). So they overlap, but how can > we still write data in DS segment? Writing to DS, so we write to CS, > but CS is READ-ONLY, so the problem would occur, right ?? The read-only flag is on the descriptor, *NOT* the memory! You *don't* write to CS. You write to memory, that can be accessed by CS. But you don't write to it through CS. CS does not apply. It's in fact the same with pages. There can be two linear addresses, that point to the same physical address -- and each of them can have different access permissions. ------------------------------------------------------------------------------- Jan 'Bulb' Hudec <bulb@xxxxxx>
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