diff options
-rw-r--r-- | arch/x86/include/asm/microcode.h | 2 | ||||
-rw-r--r-- | arch/x86/kernel/head32.c | 54 |
2 files changed, 54 insertions, 2 deletions
diff --git a/arch/x86/include/asm/microcode.h b/arch/x86/include/asm/microcode.h index bbbe9d744977..5216bf1acc3b 100644 --- a/arch/x86/include/asm/microcode.h +++ b/arch/x86/include/asm/microcode.h @@ -23,6 +23,8 @@ static inline void load_ucode_ap(void) { } static inline void microcode_bsp_resume(void) { } #endif +extern unsigned long initrd_start_early; + #ifdef CONFIG_CPU_SUP_INTEL /* Intel specific microcode defines. Public for IFS */ struct microcode_header_intel { diff --git a/arch/x86/kernel/head32.c b/arch/x86/kernel/head32.c index bdce6321fabd..abdbfd335e13 100644 --- a/arch/x86/kernel/head32.c +++ b/arch/x86/kernel/head32.c @@ -29,11 +29,33 @@ static void __init i386_default_early_setup(void) x86_init.mpparse.setup_ioapic_ids = setup_ioapic_ids_from_mpc; } +#ifdef CONFIG_MICROCODE_INITRD32 +unsigned long __initdata initrd_start_early; +static pte_t __initdata *initrd_pl2p_start, *initrd_pl2p_end; + +static void zap_early_initrd_mapping(void) +{ + pte_t *pl2p = initrd_pl2p_start; + + for (; pl2p < initrd_pl2p_end; pl2p++) { + *pl2p = (pte_t){ .pte = 0 }; + + if (!IS_ENABLED(CONFIG_X86_PAE)) + *(pl2p + ((PAGE_OFFSET >> PGDIR_SHIFT))) = (pte_t) {.pte = 0}; + } +} +#else +static inline void zap_early_initrd_mapping(void) { } +#endif + asmlinkage __visible void __init __noreturn i386_start_kernel(void) { /* Make sure IDT is set up before any exception happens */ idt_setup_early_handler(); + /* load_ucode_bsp() */ + zap_early_initrd_mapping(); + cr4_init_shadow(); sanitize_boot_params(&boot_params); @@ -105,9 +127,9 @@ static __init __no_stack_protector pte_t init_map(pte_t pte, pte_t **ptep, pl2_t void __init __no_stack_protector mk_early_pgtbl_32(void) { /* Enough space to fit pagetables for the low memory linear map */ - const unsigned long limit = __pa_nodebug(_end) + - (PAGE_TABLE_SIZE(LOWMEM_PAGES) << PAGE_SHIFT); + unsigned long limit = __pa_nodebug(_end) + (PAGE_TABLE_SIZE(LOWMEM_PAGES) << PAGE_SHIFT); pte_t pte, *ptep = (pte_t *)__pa_nodebug(__brk_base); + struct boot_params __maybe_unused *params; pl2_t *pl2p = (pl2_t *)__pa_nodebug(pl2_base); unsigned long *ptr; @@ -120,4 +142,32 @@ void __init __no_stack_protector mk_early_pgtbl_32(void) ptr = (unsigned long *)__pa_nodebug(&_brk_end); *ptr = (unsigned long)ptep + PAGE_OFFSET; + +#ifdef CONFIG_MICROCODE_INITRD32 + /* Running on a hypervisor? */ + if (native_cpuid_ecx(1) & BIT(31)) + return; + + params = (struct boot_params *)__pa_nodebug(&boot_params); + if (!params->hdr.ramdisk_size || !params->hdr.ramdisk_image) + return; + + /* Save the virtual start address */ + ptr = (unsigned long *)__pa_nodebug(&initrd_start_early); + *ptr = (pte.pte & PTE_PFN_MASK) + PAGE_OFFSET; + *ptr += ((unsigned long)params->hdr.ramdisk_image) & ~PAGE_MASK; + + /* Save PLP2 for cleanup */ + ptr = (unsigned long *)__pa_nodebug(&initrd_pl2p_start); + *ptr = (unsigned long)pl2p + PAGE_OFFSET; + + limit = (unsigned long)params->hdr.ramdisk_image; + pte.pte = PTE_IDENT_ATTR | PFN_ALIGN(limit); + limit = (unsigned long)params->hdr.ramdisk_image + params->hdr.ramdisk_size; + + init_map(pte, &ptep, &pl2p, limit); + + ptr = (unsigned long *)__pa_nodebug(&initrd_pl2p_end); + *ptr = (unsigned long)pl2p + PAGE_OFFSET; +#endif } |