Struct x86_64::registers::model_specific::Star

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pub struct Star;

Expand description

Syscall Register: STAR

Implementations§

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impl Star

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pub fn read_raw() -> (u16, u16)

Read the Ring 0 and Ring 3 segment bases. The remaining fields are ignored because they are not valid for long mode.

Returns

Field 1 (SYSRET): The CS selector is set to this field + 16. SS.Sel is set to this field + 8. Because SYSRET always returns to CPL 3, the RPL bits 1:0 should be initialized to 11b.
Field 2 (SYSCALL): This field is copied directly into CS.Sel. SS.Sel is set to this field + 8. Because SYSCALL always switches to CPL 0, the RPL bits 33:32 should be initialized to 00b.

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pub fn read( ) -> (SegmentSelector, SegmentSelector, SegmentSelector, SegmentSelector)

Read the Ring 0 and Ring 3 segment bases. Returns

CS Selector SYSRET
SS Selector SYSRET
CS Selector SYSCALL
SS Selector SYSCALL

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pub unsafe fn write_raw(sysret: u16, syscall: u16)

Write the Ring 0 and Ring 3 segment bases. The remaining fields are ignored because they are not valid for long mode.

Parameters

sysret: The CS selector is set to this field + 16. SS.Sel is set to this field + 8. Because SYSRET always returns to CPL 3, the RPL bits 1:0 should be initialized to 11b.
syscall: This field is copied directly into CS.Sel. SS.Sel is set to this field + 8. Because SYSCALL always switches to CPL 0, the RPL bits 33:32 should be initialized to 00b.

Safety

Unsafe because this can cause system instability if passed in the wrong values for the fields.

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pub fn write( cs_sysret: SegmentSelector, ss_sysret: SegmentSelector, cs_syscall: SegmentSelector, ss_syscall: SegmentSelector ) -> Result<(), &'static str>

Write the Ring 0 and Ring 3 segment bases. The remaining fields are ignored because they are not valid for long mode. This function will fail if the segment selectors are not in the correct offset of each other or if the segment selectors do not have correct privileges.

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