Commit 056c52f5 authored by H. Peter Anvin (Intel)'s avatar H. Peter Anvin (Intel) Committed by Thomas Gleixner
Browse files

x86/kexec: Set_[gi]dt() -> native_[gi]dt_invalidate() in machine_kexec_*.c 



These files contain private set_gdt() functions which are only used to
invalid the gdt; machine_kexec_64.c also contains a set_idt()
function to invalidate the idt.

phys_to_virt(0) *really* doesn't make any sense for creating an
invalid GDT. A NULL pointer (virtual 0) makes a lot more sense;
although neither will allow any actual memory reference, a NULL
pointer stands out more.

Replace these calls with native_[gi]dt_invalidate().

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/20210519212154.511983-7-hpa@zytor.com
parent 283fa3b6

arch/x86/kernel/machine_kexec_32.c

+2 −13
Original line number Diff line number Diff line
@@ -23,17 +23,6 @@ 
#include <asm/set_memory.h>

#include <asm/debugreg.h>



static void set_gdt(void *newgdt, __u16 limit)

{

	struct desc_ptr curgdt;



	/* ia32 supports unaligned loads & stores */

	curgdt.size    = limit;

	curgdt.address = (unsigned long)newgdt;



	load_gdt(&curgdt);

}



static void load_segments(void)

{

#define __STR(X) #X
@@ -232,8 +221,8 @@ void machine_kexec(struct kimage *image) 
	 * The gdt & idt are now invalid.

	 * If you want to load them you must set up your own idt & gdt.

	 */

	idt_invalidate();

	set_gdt(phys_to_virt(0), 0);

	native_idt_invalidate();

	native_gdt_invalidate();



	/* now call it */

	image->start = relocate_kernel_ptr((unsigned long)image->head,

arch/x86/kernel/machine_kexec_64.c

+2 −31
Original line number Diff line number Diff line
@@ -256,35 +256,6 @@ static int init_pgtable(struct kimage *image, unsigned long start_pgtable) 
	return init_transition_pgtable(image, level4p);

}



static void set_idt(void *newidt, u16 limit)

{

	struct desc_ptr curidt;



	/* x86-64 supports unaligned loads & stores */

	curidt.size    = limit;

	curidt.address = (unsigned long)newidt;



	__asm__ __volatile__ (

		"lidtq %0\n"

		: : "m" (curidt)

		);

};





static void set_gdt(void *newgdt, u16 limit)

{

	struct desc_ptr curgdt;



	/* x86-64 supports unaligned loads & stores */

	curgdt.size    = limit;

	curgdt.address = (unsigned long)newgdt;



	__asm__ __volatile__ (

		"lgdtq %0\n"

		: : "m" (curgdt)

		);

};



static void load_segments(void)

{

	__asm__ __volatile__ (
@@ -379,8 +350,8 @@ void machine_kexec(struct kimage *image) 
	 * The gdt & idt are now invalid.

	 * If you want to load them you must set up your own idt & gdt.

	 */

	set_gdt(phys_to_virt(0), 0);

	set_idt(phys_to_virt(0), 0);

	native_idt_invalidate();

	native_gdt_invalidate();



	/* now call it */

	image->start = relocate_kernel((unsigned long)image->head,