From 7eb4e1dd71009472215bc1f8226ee9a041da8d37 Mon Sep 17 00:00:00 2001 From: Nicolas Saenz Julienne Date: Tue, 12 Nov 2024 18:52:16 +0000 Subject: x86/efi: Drop support for the EFI_PROPERTIES_TABLE Drop support for the EFI_PROPERTIES_TABLE. It was a failed, short-lived experiment that broke the boot both on Linux and Windows, and was replaced by the EFI_MEMORY_ATTRIBUTES_TABLE shortly after. Suggested-by: Ard Biesheuvel Signed-off-by: Nicolas Saenz Julienne Signed-off-by: Ard Biesheuvel --- arch/x86/platform/efi/efi.c | 19 ------------------- arch/x86/platform/efi/efi_64.c | 42 ------------------------------------------ 2 files changed, 61 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index 88a96816de9a..375ebd78296a 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -54,14 +54,12 @@ #include static unsigned long efi_systab_phys __initdata; -static unsigned long prop_phys = EFI_INVALID_TABLE_ADDR; static unsigned long uga_phys = EFI_INVALID_TABLE_ADDR; static unsigned long efi_runtime, efi_nr_tables; unsigned long efi_fw_vendor, efi_config_table; static const efi_config_table_type_t arch_tables[] __initconst = { - {EFI_PROPERTIES_TABLE_GUID, &prop_phys, "PROP" }, {UGA_IO_PROTOCOL_GUID, &uga_phys, "UGA" }, #ifdef CONFIG_X86_UV {UV_SYSTEM_TABLE_GUID, &uv_systab_phys, "UVsystab" }, @@ -82,7 +80,6 @@ static const unsigned long * const efi_tables[] = { &efi_runtime, &efi_config_table, &efi.esrt, - &prop_phys, &efi_mem_attr_table, #ifdef CONFIG_EFI_RCI2_TABLE &rci2_table_phys, @@ -502,22 +499,6 @@ void __init efi_init(void) return; } - /* Parse the EFI Properties table if it exists */ - if (prop_phys != EFI_INVALID_TABLE_ADDR) { - efi_properties_table_t *tbl; - - tbl = early_memremap_ro(prop_phys, sizeof(*tbl)); - if (tbl == NULL) { - pr_err("Could not map Properties table!\n"); - } else { - if (tbl->memory_protection_attribute & - EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA) - set_bit(EFI_NX_PE_DATA, &efi.flags); - - early_memunmap(tbl, sizeof(*tbl)); - } - } - set_bit(EFI_RUNTIME_SERVICES, &efi.flags); efi_clean_memmap(); diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index 91d31ac422d6..ac57259a432b 100644 --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -412,51 +412,9 @@ static int __init efi_update_mem_attr(struct mm_struct *mm, efi_memory_desc_t *m void __init efi_runtime_update_mappings(void) { - efi_memory_desc_t *md; - - /* - * Use the EFI Memory Attribute Table for mapping permissions if it - * exists, since it is intended to supersede EFI_PROPERTIES_TABLE. - */ if (efi_enabled(EFI_MEM_ATTR)) { efi_disable_ibt_for_runtime = false; efi_memattr_apply_permissions(NULL, efi_update_mem_attr); - return; - } - - /* - * EFI_MEMORY_ATTRIBUTES_TABLE is intended to replace - * EFI_PROPERTIES_TABLE. So, use EFI_PROPERTIES_TABLE to update - * permissions only if EFI_MEMORY_ATTRIBUTES_TABLE is not - * published by the firmware. Even if we find a buggy implementation of - * EFI_MEMORY_ATTRIBUTES_TABLE, don't fall back to - * EFI_PROPERTIES_TABLE, because of the same reason. - */ - - if (!efi_enabled(EFI_NX_PE_DATA)) - return; - - for_each_efi_memory_desc(md) { - unsigned long pf = 0; - - if (!(md->attribute & EFI_MEMORY_RUNTIME)) - continue; - - if (!(md->attribute & EFI_MEMORY_WB)) - pf |= _PAGE_PCD; - - if ((md->attribute & EFI_MEMORY_XP) || - (md->type == EFI_RUNTIME_SERVICES_DATA)) - pf |= _PAGE_NX; - - if (!(md->attribute & EFI_MEMORY_RO) && - (md->type != EFI_RUNTIME_SERVICES_CODE)) - pf |= _PAGE_RW; - - if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) - pf |= _PAGE_ENC; - - efi_update_mappings(md, pf); } } -- cgit v1.2.3 From 21b1a7f7ae2f53c914f584a72a85cb4f71227e28 Mon Sep 17 00:00:00 2001 From: Nicolas Saenz Julienne Date: Tue, 12 Nov 2024 18:52:17 +0000 Subject: x86/efi: Apply EFI Memory Attributes after kexec Kexec bypasses EFI's switch to virtual mode. In exchange, it has its own routine, kexec_enter_virtual_mode(), which replays the mappings made by the original kernel. Unfortunately, that function fails to reinstate EFI's memory attributes, which would've otherwise been set after entering virtual mode. Remediate this by calling efi_runtime_update_mappings() within kexec's routine. Signed-off-by: Nicolas Saenz Julienne Signed-off-by: Ard Biesheuvel --- arch/x86/platform/efi/efi.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/x86') diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index 375ebd78296a..a7ff189421c3 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -765,6 +765,7 @@ static void __init kexec_enter_virtual_mode(void) efi_sync_low_kernel_mappings(); efi_native_runtime_setup(); + efi_runtime_update_mappings(); #endif } -- cgit v1.2.3