diff options
Diffstat (limited to 'arch/x86/platform/efi/efi_64.c')
-rw-r--r-- | arch/x86/platform/efi/efi_64.c | 317 |
1 files changed, 115 insertions, 202 deletions
diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index 08ce8177c3af..e2accfe636bd 100644 --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -57,142 +57,6 @@ static u64 efi_va = EFI_VA_START; struct efi_scratch efi_scratch; -static void __init early_code_mapping_set_exec(int executable) -{ - efi_memory_desc_t *md; - - if (!(__supported_pte_mask & _PAGE_NX)) - return; - - /* Make EFI service code area executable */ - for_each_efi_memory_desc(md) { - if (md->type == EFI_RUNTIME_SERVICES_CODE || - md->type == EFI_BOOT_SERVICES_CODE) - efi_set_executable(md, executable); - } -} - -pgd_t * __init efi_call_phys_prolog(void) -{ - unsigned long vaddr, addr_pgd, addr_p4d, addr_pud; - pgd_t *save_pgd, *pgd_k, *pgd_efi; - p4d_t *p4d, *p4d_k, *p4d_efi; - pud_t *pud; - - int pgd; - int n_pgds, i, j; - - if (!efi_enabled(EFI_OLD_MEMMAP)) { - efi_switch_mm(&efi_mm); - return efi_mm.pgd; - } - - early_code_mapping_set_exec(1); - - n_pgds = DIV_ROUND_UP((max_pfn << PAGE_SHIFT), PGDIR_SIZE); - save_pgd = kmalloc_array(n_pgds, sizeof(*save_pgd), GFP_KERNEL); - if (!save_pgd) - return NULL; - - /* - * Build 1:1 identity mapping for efi=old_map usage. Note that - * PAGE_OFFSET is PGDIR_SIZE aligned when KASLR is disabled, while - * it is PUD_SIZE ALIGNED with KASLR enabled. So for a given physical - * address X, the pud_index(X) != pud_index(__va(X)), we can only copy - * PUD entry of __va(X) to fill in pud entry of X to build 1:1 mapping. - * This means here we can only reuse the PMD tables of the direct mapping. - */ - for (pgd = 0; pgd < n_pgds; pgd++) { - addr_pgd = (unsigned long)(pgd * PGDIR_SIZE); - vaddr = (unsigned long)__va(pgd * PGDIR_SIZE); - pgd_efi = pgd_offset_k(addr_pgd); - save_pgd[pgd] = *pgd_efi; - - p4d = p4d_alloc(&init_mm, pgd_efi, addr_pgd); - if (!p4d) { - pr_err("Failed to allocate p4d table!\n"); - goto out; - } - - for (i = 0; i < PTRS_PER_P4D; i++) { - addr_p4d = addr_pgd + i * P4D_SIZE; - p4d_efi = p4d + p4d_index(addr_p4d); - - pud = pud_alloc(&init_mm, p4d_efi, addr_p4d); - if (!pud) { - pr_err("Failed to allocate pud table!\n"); - goto out; - } - - for (j = 0; j < PTRS_PER_PUD; j++) { - addr_pud = addr_p4d + j * PUD_SIZE; - - if (addr_pud > (max_pfn << PAGE_SHIFT)) - break; - - vaddr = (unsigned long)__va(addr_pud); - - pgd_k = pgd_offset_k(vaddr); - p4d_k = p4d_offset(pgd_k, vaddr); - pud[j] = *pud_offset(p4d_k, vaddr); - } - } - pgd_offset_k(pgd * PGDIR_SIZE)->pgd &= ~_PAGE_NX; - } - - __flush_tlb_all(); - return save_pgd; -out: - efi_call_phys_epilog(save_pgd); - return NULL; -} - -void __init efi_call_phys_epilog(pgd_t *save_pgd) -{ - /* - * After the lock is released, the original page table is restored. - */ - int pgd_idx, i; - int nr_pgds; - pgd_t *pgd; - p4d_t *p4d; - pud_t *pud; - - if (!efi_enabled(EFI_OLD_MEMMAP)) { - efi_switch_mm(efi_scratch.prev_mm); - return; - } - - nr_pgds = DIV_ROUND_UP((max_pfn << PAGE_SHIFT) , PGDIR_SIZE); - - for (pgd_idx = 0; pgd_idx < nr_pgds; pgd_idx++) { - pgd = pgd_offset_k(pgd_idx * PGDIR_SIZE); - set_pgd(pgd_offset_k(pgd_idx * PGDIR_SIZE), save_pgd[pgd_idx]); - - if (!pgd_present(*pgd)) - continue; - - for (i = 0; i < PTRS_PER_P4D; i++) { - p4d = p4d_offset(pgd, - pgd_idx * PGDIR_SIZE + i * P4D_SIZE); - - if (!p4d_present(*p4d)) - continue; - - pud = (pud_t *)p4d_page_vaddr(*p4d); - pud_free(&init_mm, pud); - } - - p4d = (p4d_t *)pgd_page_vaddr(*pgd); - p4d_free(&init_mm, p4d); - } - - kfree(save_pgd); - - __flush_tlb_all(); - early_code_mapping_set_exec(0); -} - EXPORT_SYMBOL_GPL(efi_mm); /* @@ -211,7 +75,7 @@ int __init efi_alloc_page_tables(void) pud_t *pud; gfp_t gfp_mask; - if (efi_enabled(EFI_OLD_MEMMAP)) + if (efi_have_uv1_memmap()) return 0; gfp_mask = GFP_KERNEL | __GFP_ZERO; @@ -252,7 +116,7 @@ void efi_sync_low_kernel_mappings(void) pud_t *pud_k, *pud_efi; pgd_t *efi_pgd = efi_mm.pgd; - if (efi_enabled(EFI_OLD_MEMMAP)) + if (efi_have_uv1_memmap()) return; /* @@ -346,7 +210,7 @@ int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) unsigned npages; pgd_t *pgd = efi_mm.pgd; - if (efi_enabled(EFI_OLD_MEMMAP)) + if (efi_have_uv1_memmap()) return 0; /* @@ -373,10 +237,6 @@ int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) * as trim_bios_range() will reserve the first page and isolate it away * from memory allocators anyway. */ - pf = _PAGE_RW; - if (sev_active()) - pf |= _PAGE_ENC; - if (kernel_map_pages_in_pgd(pgd, 0x0, 0x0, 1, pf)) { pr_err("Failed to create 1:1 mapping for the first page!\n"); return 1; @@ -388,21 +248,22 @@ int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) * text and allocate a new stack because we can't rely on the * stack pointer being < 4GB. */ - if (!IS_ENABLED(CONFIG_EFI_MIXED) || efi_is_native()) + if (!efi_is_mixed()) return 0; page = alloc_page(GFP_KERNEL|__GFP_DMA32); - if (!page) - panic("Unable to allocate EFI runtime stack < 4GB\n"); + if (!page) { + pr_err("Unable to allocate EFI runtime stack < 4GB\n"); + return 1; + } - efi_scratch.phys_stack = virt_to_phys(page_address(page)); - efi_scratch.phys_stack += PAGE_SIZE; /* stack grows down */ + efi_scratch.phys_stack = page_to_phys(page + 1); /* stack grows down */ - npages = (_etext - _text) >> PAGE_SHIFT; + npages = (__end_rodata_aligned - _text) >> PAGE_SHIFT; text = __pa(_text); pfn = text >> PAGE_SHIFT; - pf = _PAGE_RW | _PAGE_ENC; + pf = _PAGE_ENC; if (kernel_map_pages_in_pgd(pgd, pfn, text, npages, pf)) { pr_err("Failed to map kernel text 1:1\n"); return 1; @@ -417,6 +278,22 @@ static void __init __map_region(efi_memory_desc_t *md, u64 va) unsigned long pfn; pgd_t *pgd = efi_mm.pgd; + /* + * EFI_RUNTIME_SERVICES_CODE regions typically cover PE/COFF + * executable images in memory that consist of both R-X and + * RW- sections, so we cannot apply read-only or non-exec + * permissions just yet. However, modern EFI systems provide + * a memory attributes table that describes those sections + * with the appropriate restricted permissions, which are + * applied in efi_runtime_update_mappings() below. All other + * regions can be mapped non-executable at this point, with + * the exception of boot services code regions, but those will + * be unmapped again entirely in efi_free_boot_services(). + */ + if (md->type != EFI_BOOT_SERVICES_CODE && + md->type != EFI_RUNTIME_SERVICES_CODE) + flags |= _PAGE_NX; + if (!(md->attribute & EFI_MEMORY_WB)) flags |= _PAGE_PCD; @@ -434,7 +311,7 @@ void __init efi_map_region(efi_memory_desc_t *md) unsigned long size = md->num_pages << PAGE_SHIFT; u64 pa = md->phys_addr; - if (efi_enabled(EFI_OLD_MEMMAP)) + if (efi_have_uv1_memmap()) return old_map_region(md); /* @@ -449,7 +326,7 @@ void __init efi_map_region(efi_memory_desc_t *md) * booting in EFI mixed mode, because even though we may be * running a 64-bit kernel, the firmware may only be 32-bit. */ - if (!efi_is_native () && IS_ENABLED(CONFIG_EFI_MIXED)) { + if (efi_is_mixed()) { md->virt_addr = md->phys_addr; return; } @@ -491,26 +368,6 @@ void __init efi_map_region_fixed(efi_memory_desc_t *md) __map_region(md, md->virt_addr); } -void __iomem *__init efi_ioremap(unsigned long phys_addr, unsigned long size, - u32 type, u64 attribute) -{ - unsigned long last_map_pfn; - - if (type == EFI_MEMORY_MAPPED_IO) - return ioremap(phys_addr, size); - - last_map_pfn = init_memory_mapping(phys_addr, phys_addr + size); - if ((last_map_pfn << PAGE_SHIFT) < phys_addr + size) { - unsigned long top = last_map_pfn << PAGE_SHIFT; - efi_ioremap(top, size - (top - phys_addr), type, attribute); - } - - if (!(attribute & EFI_MEMORY_WB)) - efi_memory_uc((u64)(unsigned long)__va(phys_addr), size); - - return (void __iomem *)__va(phys_addr); -} - void __init parse_efi_setup(u64 phys_addr, u32 data_len) { efi_setup = phys_addr + sizeof(struct setup_data); @@ -559,7 +416,7 @@ void __init efi_runtime_update_mappings(void) { efi_memory_desc_t *md; - if (efi_enabled(EFI_OLD_MEMMAP)) { + if (efi_have_uv1_memmap()) { if (__supported_pte_mask & _PAGE_NX) runtime_code_page_mkexec(); return; @@ -613,7 +470,7 @@ void __init efi_runtime_update_mappings(void) void __init efi_dump_pagetable(void) { #ifdef CONFIG_EFI_PGT_DUMP - if (efi_enabled(EFI_OLD_MEMMAP)) + if (efi_have_uv1_memmap()) ptdump_walk_pgd_level(NULL, swapper_pg_dir); else ptdump_walk_pgd_level(NULL, efi_mm.pgd); @@ -634,63 +491,74 @@ void efi_switch_mm(struct mm_struct *mm) switch_mm(efi_scratch.prev_mm, mm, NULL); } -#ifdef CONFIG_EFI_MIXED -extern efi_status_t efi64_thunk(u32, ...); - static DEFINE_SPINLOCK(efi_runtime_lock); -#define runtime_service32(func) \ -({ \ - u32 table = (u32)(unsigned long)efi.systab; \ - u32 *rt, *___f; \ - \ - rt = (u32 *)(table + offsetof(efi_system_table_32_t, runtime)); \ - ___f = (u32 *)(*rt + offsetof(efi_runtime_services_32_t, func)); \ - *___f; \ +/* + * DS and ES contain user values. We need to save them. + * The 32-bit EFI code needs a valid DS, ES, and SS. There's no + * need to save the old SS: __KERNEL_DS is always acceptable. + */ +#define __efi_thunk(func, ...) \ +({ \ + efi_runtime_services_32_t *__rt; \ + unsigned short __ds, __es; \ + efi_status_t ____s; \ + \ + __rt = (void *)(unsigned long)efi.systab->mixed_mode.runtime; \ + \ + savesegment(ds, __ds); \ + savesegment(es, __es); \ + \ + loadsegment(ss, __KERNEL_DS); \ + loadsegment(ds, __KERNEL_DS); \ + loadsegment(es, __KERNEL_DS); \ + \ + ____s = efi64_thunk(__rt->func, __VA_ARGS__); \ + \ + loadsegment(ds, __ds); \ + loadsegment(es, __es); \ + \ + ____s ^= (____s & BIT(31)) | (____s & BIT_ULL(31)) << 32; \ + ____s; \ }) /* * Switch to the EFI page tables early so that we can access the 1:1 * runtime services mappings which are not mapped in any other page - * tables. This function must be called before runtime_service32(). + * tables. * * Also, disable interrupts because the IDT points to 64-bit handlers, * which aren't going to function correctly when we switch to 32-bit. */ -#define efi_thunk(f, ...) \ +#define efi_thunk(func...) \ ({ \ efi_status_t __s; \ - u32 __func; \ \ arch_efi_call_virt_setup(); \ \ - __func = runtime_service32(f); \ - __s = efi64_thunk(__func, __VA_ARGS__); \ + __s = __efi_thunk(func); \ \ arch_efi_call_virt_teardown(); \ \ __s; \ }) -efi_status_t efi_thunk_set_virtual_address_map( - void *phys_set_virtual_address_map, - unsigned long memory_map_size, - unsigned long descriptor_size, - u32 descriptor_version, - efi_memory_desc_t *virtual_map) +static efi_status_t __init __no_sanitize_address +efi_thunk_set_virtual_address_map(unsigned long memory_map_size, + unsigned long descriptor_size, + u32 descriptor_version, + efi_memory_desc_t *virtual_map) { efi_status_t status; unsigned long flags; - u32 func; efi_sync_low_kernel_mappings(); local_irq_save(flags); efi_switch_mm(&efi_mm); - func = (u32)(unsigned long)phys_set_virtual_address_map; - status = efi64_thunk(func, memory_map_size, descriptor_size, - descriptor_version, virtual_map); + status = __efi_thunk(set_virtual_address_map, memory_map_size, + descriptor_size, descriptor_version, virtual_map); efi_switch_mm(efi_scratch.prev_mm); local_irq_restore(flags); @@ -993,8 +861,11 @@ efi_thunk_query_capsule_caps(efi_capsule_header_t **capsules, return EFI_UNSUPPORTED; } -void efi_thunk_runtime_setup(void) +void __init efi_thunk_runtime_setup(void) { + if (!IS_ENABLED(CONFIG_EFI_MIXED)) + return; + efi.get_time = efi_thunk_get_time; efi.set_time = efi_thunk_set_time; efi.get_wakeup_time = efi_thunk_get_wakeup_time; @@ -1010,4 +881,46 @@ void efi_thunk_runtime_setup(void) efi.update_capsule = efi_thunk_update_capsule; efi.query_capsule_caps = efi_thunk_query_capsule_caps; } -#endif /* CONFIG_EFI_MIXED */ + +efi_status_t __init __no_sanitize_address +efi_set_virtual_address_map(unsigned long memory_map_size, + unsigned long descriptor_size, + u32 descriptor_version, + efi_memory_desc_t *virtual_map) +{ + efi_status_t status; + unsigned long flags; + pgd_t *save_pgd = NULL; + + if (efi_is_mixed()) + return efi_thunk_set_virtual_address_map(memory_map_size, + descriptor_size, + descriptor_version, + virtual_map); + + if (efi_have_uv1_memmap()) { + save_pgd = efi_uv1_memmap_phys_prolog(); + if (!save_pgd) + return EFI_ABORTED; + } else { + efi_switch_mm(&efi_mm); + } + + kernel_fpu_begin(); + + /* Disable interrupts around EFI calls: */ + local_irq_save(flags); + status = efi_call(efi.systab->runtime->set_virtual_address_map, + memory_map_size, descriptor_size, + descriptor_version, virtual_map); + local_irq_restore(flags); + + kernel_fpu_end(); + + if (save_pgd) + efi_uv1_memmap_phys_epilog(save_pgd); + else + efi_switch_mm(efi_scratch.prev_mm); + + return status; +} |