linux/arch/x86/boot/compressed/idt_64.c
Joerg Roedel 597cfe4821 x86/boot/compressed/64: Setup a GHCB-based VC Exception handler
Install an exception handler for #VC exception that uses a GHCB. Also
add the infrastructure for handling different exit-codes by decoding
the instruction that caused the exception and error handling.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200907131613.12703-24-joro@8bytes.org
2020-09-07 19:45:25 +02:00

55 lines
1.3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
#include <asm/trap_pf.h>
#include <asm/segment.h>
#include <asm/trapnr.h>
#include "misc.h"
static void set_idt_entry(int vector, void (*handler)(void))
{
unsigned long address = (unsigned long)handler;
gate_desc entry;
memset(&entry, 0, sizeof(entry));
entry.offset_low = (u16)(address & 0xffff);
entry.segment = __KERNEL_CS;
entry.bits.type = GATE_TRAP;
entry.bits.p = 1;
entry.offset_middle = (u16)((address >> 16) & 0xffff);
entry.offset_high = (u32)(address >> 32);
memcpy(&boot_idt[vector], &entry, sizeof(entry));
}
/* Have this here so we don't need to include <asm/desc.h> */
static void load_boot_idt(const struct desc_ptr *dtr)
{
asm volatile("lidt %0"::"m" (*dtr));
}
/* Setup IDT before kernel jumping to .Lrelocated */
void load_stage1_idt(void)
{
boot_idt_desc.address = (unsigned long)boot_idt;
if (IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT))
set_idt_entry(X86_TRAP_VC, boot_stage1_vc);
load_boot_idt(&boot_idt_desc);
}
/* Setup IDT after kernel jumping to .Lrelocated */
void load_stage2_idt(void)
{
boot_idt_desc.address = (unsigned long)boot_idt;
set_idt_entry(X86_TRAP_PF, boot_page_fault);
#ifdef CONFIG_AMD_MEM_ENCRYPT
set_idt_entry(X86_TRAP_VC, boot_stage2_vc);
#endif
load_boot_idt(&boot_idt_desc);
}