Commit a1041713 authored by Ard Biesheuvel's avatar Ard Biesheuvel Committed by Matt Fleming
Browse files

efi: Introduce EFI_NX_PE_DATA bit and set it from properties table 



UEFI v2.5 introduces a runtime memory protection feature that splits
PE/COFF runtime images into separate code and data regions. Since this
may require special handling by the OS, allocate a EFI_xxx bit to
keep track of whether this feature is currently active or not.

Signed-off-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: default avatarMatt Fleming <matt.fleming@intel.com>
parent bf924863

drivers/firmware/efi/efi.c

+18 −0
Original line number Diff line number Diff line
@@ -426,6 +426,24 @@ int __init efi_config_parse_tables(void *config_tables, int count, int sz, 
	}

	pr_cont("\n");

	set_bit(EFI_CONFIG_TABLES, &efi.flags);



	/* Parse the EFI Properties table if it exists */

	if (efi.properties_table != EFI_INVALID_TABLE_ADDR) {

		efi_properties_table_t *tbl;



		tbl = early_memremap(efi.properties_table, sizeof(*tbl));

		if (tbl == NULL) {

			pr_err("Could not map Properties table!\n");

			return -ENOMEM;

		}



		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));

	}



	return 0;

}

include/linux/efi.h

+1 −0
Original line number Diff line number Diff line
@@ -973,6 +973,7 @@ extern int __init efi_setup_pcdp_console(char *); 
#define EFI_PARAVIRT		6	/* Access is via a paravirt interface */

#define EFI_ARCH_1		7	/* First arch-specific bit */

#define EFI_DBG			8	/* Print additional debug info at runtime */

#define EFI_NX_PE_DATA		9	/* Can runtime data regions be mapped non-executable? */



#ifdef CONFIG_EFI

/*

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