Merge branches 'pm-core', 'pm-qos', 'pm-domains' and 'pm-opp'

[linux.git] / arch / x86 / platform / efi / efi_64.c

diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
index 319148bd4b05091d24576a7535b10aad7bec0c2d..a4695da42d77b39cec3b65083c7b7115b1faa32d 100644 (file)
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c
@@ -268,6 +268,22 @@ int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)
 
        efi_scratch.use_pgd = true;
 
+       /*
+        * Certain firmware versions are way too sentimential and still believe
+        * they are exclusive and unquestionable owners of the first physical page,
+        * even though they explicitly mark it as EFI_CONVENTIONAL_MEMORY
+        * (but then write-access it later during SetVirtualAddressMap()).
+        *
+        * Create a 1:1 mapping for this page, to avoid triple faults during early
+        * boot with such firmware. We are free to hand this page to the BIOS,
+        * as trim_bios_range() will reserve the first page and isolate it away
+        * from memory allocators anyway.
+        */
+       if (kernel_map_pages_in_pgd(pgd, 0x0, 0x0, 1, _PAGE_RW)) {
+               pr_err("Failed to create 1:1 mapping for the first page!\n");
+               return 1;
+       }
+
        /*
         * When making calls to the firmware everything needs to be 1:1
         * mapped and addressable with 32-bit pointers. Map the kernel
@@ -398,10 +414,44 @@ void __init parse_efi_setup(u64 phys_addr, u32 data_len)
        efi_setup = phys_addr + sizeof(struct setup_data);
 }
 
-void __init efi_runtime_update_mappings(void)
+static int __init efi_update_mappings(efi_memory_desc_t *md, unsigned long pf)
 {
        unsigned long pfn;
        pgd_t *pgd = efi_pgd;
+       int err1, err2;
+
+       /* Update the 1:1 mapping */
+       pfn = md->phys_addr >> PAGE_SHIFT;
+       err1 = kernel_map_pages_in_pgd(pgd, pfn, md->phys_addr, md->num_pages, pf);
+       if (err1) {
+               pr_err("Error while updating 1:1 mapping PA 0x%llx -> VA 0x%llx!\n",
+                          md->phys_addr, md->virt_addr);
+       }
+
+       err2 = kernel_map_pages_in_pgd(pgd, pfn, md->virt_addr, md->num_pages, pf);
+       if (err2) {
+               pr_err("Error while updating VA mapping PA 0x%llx -> VA 0x%llx!\n",
+                          md->phys_addr, md->virt_addr);
+       }
+
+       return err1 || err2;
+}
+
+static int __init efi_update_mem_attr(struct mm_struct *mm, efi_memory_desc_t *md)
+{
+       unsigned long pf = 0;
+
+       if (md->attribute & EFI_MEMORY_XP)
+               pf |= _PAGE_NX;
+
+       if (!(md->attribute & EFI_MEMORY_RO))
+               pf |= _PAGE_RW;
+
+       return efi_update_mappings(md, pf);
+}
+
+void __init efi_runtime_update_mappings(void)
+{
        efi_memory_desc_t *md;
 
        if (efi_enabled(EFI_OLD_MEMMAP)) {
@@ -410,6 +460,24 @@ void __init efi_runtime_update_mappings(void)
                return;
        }
 
+       /*
+        * 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_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;
 
@@ -430,15 +498,7 @@ void __init efi_runtime_update_mappings(void)
                        (md->type != EFI_RUNTIME_SERVICES_CODE))
                        pf |= _PAGE_RW;
 
-               /* Update the 1:1 mapping */
-               pfn = md->phys_addr >> PAGE_SHIFT;
-               if (kernel_map_pages_in_pgd(pgd, pfn, md->phys_addr, md->num_pages, pf))
-                       pr_warn("Error mapping PA 0x%llx -> VA 0x%llx!\n",
-                                  md->phys_addr, md->virt_addr);
-
-               if (kernel_map_pages_in_pgd(pgd, pfn, md->virt_addr, md->num_pages, pf))
-                       pr_warn("Error mapping PA 0x%llx -> VA 0x%llx!\n",
-                                  md->phys_addr, md->virt_addr);
+               efi_update_mappings(md, pf);
        }
 }