From: Joerg Roedel <jroe...@suse.de> Load the IDT right after switching to virtual addresses in head_64.S so that the kernel can handle #VC exceptions.
Signed-off-by: Joerg Roedel <jroe...@suse.de> Link: https://lore.kernel.org/r/20200724160336.5435-36-j...@8bytes.org --- arch/x86/include/asm/setup.h | 3 +++ arch/x86/kernel/head64.c | 3 +++ arch/x86/kernel/head_64.S | 5 +++++ arch/x86/kernel/idt.c | 23 +++++++++++++++++++++++ 4 files changed, 34 insertions(+) diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h index 8aa6ba0427b0..5c09f50ecf1c 100644 --- a/arch/x86/include/asm/setup.h +++ b/arch/x86/include/asm/setup.h @@ -50,6 +50,8 @@ extern unsigned long __startup_64(unsigned long physaddr, struct boot_params *bp extern unsigned long __startup_secondary_64(void); extern void startup_64_setup_env(unsigned long physbase); extern int early_make_pgtable(unsigned long address); +extern void early_idt_setup_early_handler(unsigned long physaddr); +extern void early_load_idt(void); #ifdef CONFIG_X86_INTEL_MID extern void x86_intel_mid_early_setup(void); @@ -66,6 +68,7 @@ static inline void x86_ce4100_early_setup(void) { } #ifndef _SETUP #include <asm/espfix.h> +#include <asm/sections.h> #include <linux/kernel.h> /* diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 8703292a35e9..096b09d06d1c 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -286,6 +286,9 @@ unsigned long __head __startup_64(unsigned long physaddr, } } + /* Setup IDT with early handlers */ + early_idt_setup_early_handler(physaddr); + /* * Return the SME encryption mask (if SME is active) to be used as a * modifier for the initial pgdir entry programmed into CR3. diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index a5e1939d1dc9..28de83fecda3 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -206,6 +206,11 @@ SYM_CODE_START(secondary_startup_64) */ movq initial_stack(%rip), %rsp + /* Load IDT */ + pushq %rsi + call early_load_idt + popq %rsi + /* Check if nx is implemented */ movl $0x80000001, %eax cpuid diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c index c19773174221..e2777cc264f5 100644 --- a/arch/x86/kernel/idt.c +++ b/arch/x86/kernel/idt.c @@ -10,6 +10,7 @@ #include <asm/proto.h> #include <asm/desc.h> #include <asm/hw_irq.h> +#include <asm/setup.h> struct idt_data { unsigned int vector; @@ -385,3 +386,25 @@ void __init alloc_intr_gate(unsigned int n, const void *addr) if (!WARN_ON(test_and_set_bit(n, system_vectors))) set_intr_gate(n, addr); } + +void __init early_idt_setup_early_handler(unsigned long physaddr) +{ + gate_desc *idt; + int i; + + idt = fixup_pointer(idt_table, physaddr); + + for (i = 0; i < NUM_EXCEPTION_VECTORS; i++) { + struct idt_data data; + gate_desc desc; + + init_idt_data(&data, i, early_idt_handler_array[i]); + idt_init_desc(&desc, &data); + native_write_idt_entry(idt, i, &desc); + } +} + +void early_load_idt(void) +{ + load_idt(&idt_descr); +} -- 2.28.0
