[PATCH 6/6] efi: Add EFI_SECURE_BOOT bit [ver #2]
From: David Howells <dhowells@redhat.com>
Date: 2016-11-23 00:24:22
Also in:
lkml
Subsystem:
extensible firmware interface (efi), the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Ard Biesheuvel, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
From: Josh Boyer <redacted> UEFI machines can be booted in Secure Boot mode. Add a EFI_SECURE_BOOT bit that can be passed to efi_enabled() to find out whether secure boot is enabled. This will be used by the SysRq+x handler, registered by the x86 arch, to find out whether secure boot mode is enabled so that it can be disabled. Signed-off-by: Josh Boyer <redacted> Signed-off-by: David Howells <dhowells@redhat.com> --- arch/x86/kernel/setup.c | 7 +++++++ include/linux/efi.h | 1 + 2 files changed, 8 insertions(+)
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 9c337b0e8ba7..522915d6de1f 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c@@ -1160,6 +1160,13 @@ void __init setup_arch(char **cmdline_p) io_delay_init(); +#ifdef CONFIG_EFI + if (boot_params.secure_boot) { + set_bit(EFI_SECURE_BOOT, &efi.flags); + pr_info("Secure boot enabled\n"); + } +#endif + /* * Parse the ACPI tables for possible boot-time SMP configuration. */
diff --git a/include/linux/efi.h b/include/linux/efi.h
index ff01ad6f2823..d95bb9e69974 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h@@ -1066,6 +1066,7 @@ extern int __init efi_setup_pcdp_console(char *); #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? */ +#define EFI_SECURE_BOOT 10 /* Are we in Secure Boot mode? */ #ifdef CONFIG_EFI /*