Commit 283fa3b6 authored by H. Peter Anvin (Intel)'s avatar H. Peter Anvin (Intel) Committed by Thomas Gleixner
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x86: Add native_[ig]dt_invalidate() 



In some places, the native forms of descriptor table invalidation is
required. Rather than open-coding them, add explicitly native functions to
invalidate the GDT and IDT.

Signed-off-by: default avatarH. Peter Anvin (Intel) <hpa@zytor.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210519212154.511983-6-hpa@zytor.com
parent 8ec9069a

arch/x86/include/asm/desc.h

+20 −0
Original line number Diff line number Diff line
@@ -224,6 +224,26 @@ static inline void store_idt(struct desc_ptr *dtr) 
	asm volatile("sidt %0":"=m" (*dtr));

}



static inline void native_gdt_invalidate(void)

{

	const struct desc_ptr invalid_gdt = {

		.address = 0,

		.size = 0

	};



	native_load_gdt(&invalid_gdt);

}



static inline void native_idt_invalidate(void)

{

	const struct desc_ptr invalid_idt = {

		.address = 0,

		.size = 0

	};



	native_load_idt(&invalid_idt);

}



/*

 * The LTR instruction marks the TSS GDT entry as busy. On 64-bit, the GDT is

 * a read-only remapping. To prevent a page fault, the GDT is switched to the