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Inline load_segments

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This commit is contained in:
bjorn3
2025-09-16 19:58:56 +02:00
parent 647c87c5a0
commit 25d526e9a1
1 changed files with 10 additions and 18 deletions
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src/arch/x86_shared/gdt.rs
+10 -18
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@@ -254,23 +254,6 @@ pub unsafe fn set_userspace_io_allowed(pcr: *mut ProcessorControlRegion, allowed
}
}
#[cold]
#[cfg(target_arch = "x86_64")]
unsafe fn load_segments() {
unsafe {
segmentation::load_cs(SegmentSelector::new(GDT_KERNEL_CODE as u16, Ring::Ring0));
segmentation::load_ss(SegmentSelector::new(GDT_KERNEL_DATA as u16, Ring::Ring0));
segmentation::load_ds(SegmentSelector::from_raw(0));
segmentation::load_es(SegmentSelector::from_raw(0));
segmentation::load_fs(SegmentSelector::from_raw(0));
// What happens when GS is loaded with a NULL selector, is undefined on Intel CPUs. However,
// GSBASE is set later.
segmentation::load_gs(SegmentSelector::from_raw(0));
}
}
#[cold]
fn init_pcr(pcr: &mut ProcessorControlRegion, stack_end: usize) {
pcr.self_ref = pcr as *mut _;
@@ -341,7 +324,16 @@ pub unsafe fn install_pcr(pcr_ptr: *mut ProcessorControlRegion) {
#[cfg(target_arch = "x86_64")]
unsafe {
// Load segments again, possibly resetting FSBASE and GSBASE.
load_segments();
segmentation::load_cs(SegmentSelector::new(GDT_KERNEL_CODE as u16, Ring::Ring0));
segmentation::load_ss(SegmentSelector::new(GDT_KERNEL_DATA as u16, Ring::Ring0));
segmentation::load_ds(SegmentSelector::from_raw(0));
segmentation::load_es(SegmentSelector::from_raw(0));
segmentation::load_fs(SegmentSelector::from_raw(0));
// What happens when GS is loaded with a NULL selector, is undefined on Intel CPUs. However,
// GSBASE is set later.
segmentation::load_gs(SegmentSelector::from_raw(0));
// Ensure that GSBASE always points to the PCR in kernel space.
x86::msr::wrmsr(x86::msr::IA32_GS_BASE, pcr as *mut _ as usize as u64);