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include vmm.inc
 
VMMcall _SetDescriptor, <Selector, VM, DescDWORD1, DescDWORD2, flags>
 
or      eax, eax        ; nonzero if set, zero if error
jz      not_set
 
The _SetDescriptor service sets (changes) the descriptor of the given
selector.
 
Parameter   Description
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Selector    Specifies the GDT or LDT selector to set.
 
VM          Specifies a handle identifying the virtual machine to which the
            specified LDT selector belongs. The service ignores this
            parameter if Selector is a GDT selector. Otherwise, the handle
            must be valid for LDT selectors.
 
DescDWORD1  Specifies the high doubleword of the descriptor for the
            selector. This parameter contains the high 16 bits of the base
            address, the high 4 bits of the limit, and the status and type
            bits.
 
DescDWORD2  Specifies the low doubleword of the descriptor for the selector.
            This parameter contains the low 16 bits of the base address and
            limit.
 
flags       Specifies the operation flags. This parameter must be set to 0.
 
Return Value
 
The EAX register contains a nonzero value if the service is successful.
Otherwise, EAX contains zero to indicate an error, such as an invalid
selector or an invalid virtual machine handle.
 
Comments
 
This service ignores the high 16-bits of the Selector parameter; the 80386
CPU often sets these bits to random values when doubleword operations are
performed on segment registers.
 
The service ignores the RPL bits of the selector.
 
Uses
 
EAX
 
See Also
 
_GetDescriptor
 
 
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