diff options
Diffstat (limited to 'arch/x86/kernel/head64.c')
| -rw-r--r-- | arch/x86/kernel/head64.c | 175 |
1 files changed, 60 insertions, 115 deletions
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index dc09560679..a817ed0724 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -22,6 +22,8 @@ #include <linux/cc_platform.h> #include <linux/pgtable.h> +#include <asm/asm.h> +#include <asm/page_64.h> #include <asm/processor.h> #include <asm/proto.h> #include <asm/smp.h> @@ -67,42 +69,11 @@ unsigned long vmemmap_base __ro_after_init = __VMEMMAP_BASE_L4; EXPORT_SYMBOL(vmemmap_base); #endif -/* - * GDT used on the boot CPU before switching to virtual addresses. - */ -static struct desc_struct startup_gdt[GDT_ENTRIES] __initdata = { - [GDT_ENTRY_KERNEL32_CS] = GDT_ENTRY_INIT(DESC_CODE32, 0, 0xfffff), - [GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(DESC_CODE64, 0, 0xfffff), - [GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(DESC_DATA64, 0, 0xfffff), -}; - -/* - * Address needs to be set at runtime because it references the startup_gdt - * while the kernel still uses a direct mapping. - */ -static struct desc_ptr startup_gdt_descr __initdata = { - .size = sizeof(startup_gdt)-1, - .address = 0, -}; - -static void __head *fixup_pointer(void *ptr, unsigned long physaddr) -{ - return ptr - (void *)_text + (void *)physaddr; -} - -static unsigned long __head *fixup_long(void *ptr, unsigned long physaddr) +static inline bool check_la57_support(void) { - return fixup_pointer(ptr, physaddr); -} - -#ifdef CONFIG_X86_5LEVEL -static unsigned int __head *fixup_int(void *ptr, unsigned long physaddr) -{ - return fixup_pointer(ptr, physaddr); -} + if (!IS_ENABLED(CONFIG_X86_5LEVEL)) + return false; -static bool __head check_la57_support(unsigned long physaddr) -{ /* * 5-level paging is detected and enabled at kernel decompression * stage. Only check if it has been enabled there. @@ -110,21 +81,15 @@ static bool __head check_la57_support(unsigned long physaddr) if (!(native_read_cr4() & X86_CR4_LA57)) return false; - *fixup_int(&__pgtable_l5_enabled, physaddr) = 1; - *fixup_int(&pgdir_shift, physaddr) = 48; - *fixup_int(&ptrs_per_p4d, physaddr) = 512; - *fixup_long(&page_offset_base, physaddr) = __PAGE_OFFSET_BASE_L5; - *fixup_long(&vmalloc_base, physaddr) = __VMALLOC_BASE_L5; - *fixup_long(&vmemmap_base, physaddr) = __VMEMMAP_BASE_L5; + RIP_REL_REF(__pgtable_l5_enabled) = 1; + RIP_REL_REF(pgdir_shift) = 48; + RIP_REL_REF(ptrs_per_p4d) = 512; + RIP_REL_REF(page_offset_base) = __PAGE_OFFSET_BASE_L5; + RIP_REL_REF(vmalloc_base) = __VMALLOC_BASE_L5; + RIP_REL_REF(vmemmap_base) = __VMEMMAP_BASE_L5; return true; } -#else -static bool __head check_la57_support(unsigned long physaddr) -{ - return false; -} -#endif static unsigned long __head sme_postprocess_startup(struct boot_params *bp, pmdval_t *pmd) { @@ -173,23 +138,22 @@ static unsigned long __head sme_postprocess_startup(struct boot_params *bp, pmdv * doesn't have to generate PC-relative relocations when accessing globals from * that function. Clang actually does not generate them, which leads to * boot-time crashes. To work around this problem, every global pointer must - * be adjusted using fixup_pointer(). + * be accessed using RIP_REL_REF(). */ unsigned long __head __startup_64(unsigned long physaddr, struct boot_params *bp) { - unsigned long load_delta, *p; + pmd_t (*early_pgts)[PTRS_PER_PMD] = RIP_REL_REF(early_dynamic_pgts); unsigned long pgtable_flags; + unsigned long load_delta; pgdval_t *pgd; p4dval_t *p4d; pudval_t *pud; pmdval_t *pmd, pmd_entry; - pteval_t *mask_ptr; bool la57; int i; - unsigned int *next_pgt_ptr; - la57 = check_la57_support(physaddr); + la57 = check_la57_support(); /* Is the address too large? */ if (physaddr >> MAX_PHYSMEM_BITS) @@ -200,6 +164,7 @@ unsigned long __head __startup_64(unsigned long physaddr, * and the address I am actually running at. */ load_delta = physaddr - (unsigned long)(_text - __START_KERNEL_map); + RIP_REL_REF(phys_base) = load_delta; /* Is the address not 2M aligned? */ if (load_delta & ~PMD_MASK) @@ -210,26 +175,21 @@ unsigned long __head __startup_64(unsigned long physaddr, /* Fixup the physical addresses in the page table */ - pgd = fixup_pointer(early_top_pgt, physaddr); - p = pgd + pgd_index(__START_KERNEL_map); - if (la57) - *p = (unsigned long)level4_kernel_pgt; - else - *p = (unsigned long)level3_kernel_pgt; - *p += _PAGE_TABLE_NOENC - __START_KERNEL_map + load_delta; + pgd = &RIP_REL_REF(early_top_pgt)->pgd; + pgd[pgd_index(__START_KERNEL_map)] += load_delta; if (la57) { - p4d = fixup_pointer(level4_kernel_pgt, physaddr); - p4d[511] += load_delta; + p4d = (p4dval_t *)&RIP_REL_REF(level4_kernel_pgt); + p4d[MAX_PTRS_PER_P4D - 1] += load_delta; + + pgd[pgd_index(__START_KERNEL_map)] = (pgdval_t)p4d | _PAGE_TABLE; } - pud = fixup_pointer(level3_kernel_pgt, physaddr); - pud[510] += load_delta; - pud[511] += load_delta; + RIP_REL_REF(level3_kernel_pgt)[PTRS_PER_PUD - 2].pud += load_delta; + RIP_REL_REF(level3_kernel_pgt)[PTRS_PER_PUD - 1].pud += load_delta; - pmd = fixup_pointer(level2_fixmap_pgt, physaddr); for (i = FIXMAP_PMD_TOP; i > FIXMAP_PMD_TOP - FIXMAP_PMD_NUM; i--) - pmd[i] += load_delta; + RIP_REL_REF(level2_fixmap_pgt)[i].pmd += load_delta; /* * Set up the identity mapping for the switchover. These @@ -238,15 +198,14 @@ unsigned long __head __startup_64(unsigned long physaddr, * it avoids problems around wraparound. */ - next_pgt_ptr = fixup_pointer(&next_early_pgt, physaddr); - pud = fixup_pointer(early_dynamic_pgts[(*next_pgt_ptr)++], physaddr); - pmd = fixup_pointer(early_dynamic_pgts[(*next_pgt_ptr)++], physaddr); + pud = &early_pgts[0]->pmd; + pmd = &early_pgts[1]->pmd; + RIP_REL_REF(next_early_pgt) = 2; pgtable_flags = _KERNPG_TABLE_NOENC + sme_get_me_mask(); if (la57) { - p4d = fixup_pointer(early_dynamic_pgts[(*next_pgt_ptr)++], - physaddr); + p4d = &early_pgts[RIP_REL_REF(next_early_pgt)++]->pmd; i = (physaddr >> PGDIR_SHIFT) % PTRS_PER_PGD; pgd[i + 0] = (pgdval_t)p4d + pgtable_flags; @@ -267,8 +226,7 @@ unsigned long __head __startup_64(unsigned long physaddr, pmd_entry = __PAGE_KERNEL_LARGE_EXEC & ~_PAGE_GLOBAL; /* Filter out unsupported __PAGE_KERNEL_* bits: */ - mask_ptr = fixup_pointer(&__supported_pte_mask, physaddr); - pmd_entry &= *mask_ptr; + pmd_entry &= RIP_REL_REF(__supported_pte_mask); pmd_entry += sme_get_me_mask(); pmd_entry += physaddr; @@ -294,7 +252,7 @@ unsigned long __head __startup_64(unsigned long physaddr, * error, causing the BIOS to halt the system. */ - pmd = fixup_pointer(level2_kernel_pgt, physaddr); + pmd = &RIP_REL_REF(level2_kernel_pgt)->pmd; /* invalidate pages before the kernel image */ for (i = 0; i < pmd_index((unsigned long)_text); i++) @@ -309,12 +267,6 @@ unsigned long __head __startup_64(unsigned long physaddr, for (; i < PTRS_PER_PMD; i++) pmd[i] &= ~_PAGE_PRESENT; - /* - * Fixup phys_base - remove the memory encryption mask to obtain - * the true physical address. - */ - *fixup_long(&phys_base, physaddr) += load_delta - sme_get_me_mask(); - return sme_postprocess_startup(bp, pmd); } @@ -569,62 +521,52 @@ void __init __noreturn x86_64_start_reservations(char *real_mode_data) */ static gate_desc bringup_idt_table[NUM_EXCEPTION_VECTORS] __page_aligned_data; -static struct desc_ptr bringup_idt_descr = { - .size = (NUM_EXCEPTION_VECTORS * sizeof(gate_desc)) - 1, - .address = 0, /* Set at runtime */ -}; - -static void set_bringup_idt_handler(gate_desc *idt, int n, void *handler) +/* This may run while still in the direct mapping */ +static void __head startup_64_load_idt(void *vc_handler) { -#ifdef CONFIG_AMD_MEM_ENCRYPT + struct desc_ptr desc = { + .address = (unsigned long)&RIP_REL_REF(bringup_idt_table), + .size = sizeof(bringup_idt_table) - 1, + }; struct idt_data data; - gate_desc desc; - - init_idt_data(&data, n, handler); - idt_init_desc(&desc, &data); - native_write_idt_entry(idt, n, &desc); -#endif -} + gate_desc idt_desc; -/* This runs while still in the direct mapping */ -static void __head startup_64_load_idt(unsigned long physbase) -{ - struct desc_ptr *desc = fixup_pointer(&bringup_idt_descr, physbase); - gate_desc *idt = fixup_pointer(bringup_idt_table, physbase); - - - if (IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT)) { - void *handler; - - /* VMM Communication Exception */ - handler = fixup_pointer(vc_no_ghcb, physbase); - set_bringup_idt_handler(idt, X86_TRAP_VC, handler); + /* @vc_handler is set only for a VMM Communication Exception */ + if (vc_handler) { + init_idt_data(&data, X86_TRAP_VC, vc_handler); + idt_init_desc(&idt_desc, &data); + native_write_idt_entry((gate_desc *)desc.address, X86_TRAP_VC, &idt_desc); } - desc->address = (unsigned long)idt; - native_load_idt(desc); + native_load_idt(&desc); } /* This is used when running on kernel addresses */ void early_setup_idt(void) { - /* VMM Communication Exception */ + void *handler = NULL; + if (IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT)) { setup_ghcb(); - set_bringup_idt_handler(bringup_idt_table, X86_TRAP_VC, vc_boot_ghcb); + handler = vc_boot_ghcb; } - bringup_idt_descr.address = (unsigned long)bringup_idt_table; - native_load_idt(&bringup_idt_descr); + startup_64_load_idt(handler); } /* * Setup boot CPU state needed before kernel switches to virtual addresses. */ -void __head startup_64_setup_env(unsigned long physbase) +void __head startup_64_setup_gdt_idt(void) { + void *handler = NULL; + + struct desc_ptr startup_gdt_descr = { + .address = (unsigned long)&RIP_REL_REF(init_per_cpu_var(gdt_page.gdt)), + .size = GDT_SIZE - 1, + }; + /* Load GDT */ - startup_gdt_descr.address = (unsigned long)fixup_pointer(startup_gdt, physbase); native_load_gdt(&startup_gdt_descr); /* New GDT is live - reload data segment registers */ @@ -632,5 +574,8 @@ void __head startup_64_setup_env(unsigned long physbase) "movl %%eax, %%ss\n" "movl %%eax, %%es\n" : : "a"(__KERNEL_DS) : "memory"); - startup_64_load_idt(physbase); + if (IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT)) + handler = &RIP_REL_REF(vc_no_ghcb); + + startup_64_load_idt(handler); } |