Commit 0f5b2c69 authored Jun 20, 2022 by Ard Biesheuvel

efi: vars: Remove deprecated 'efivars' sysfs interface

Commit 5d9db883 ("efi: Add support for a UEFI variable filesystem")
dated Oct 5, 2012, introduced a new efivarfs pseudo-filesystem to
replace the efivars sysfs interface that was used up to that point to
expose EFI variables to user space.

The main problem with the sysfs interface was that it only supported up
to 1024 bytes of payload per file, whereas the underlying variables
themselves are only bounded by a platform specific per-variable and
global limit that is typically much higher than 1024 bytes.

The deprecated sysfs interface is only enabled on x86 and Itanium, other
EFI enabled architectures only support the efivarfs pseudo-filesystem.

So let's finally rip off the band aid, and drop the old interface
entirely. This will make it easier to refactor and clean up the
underlying infrastructure that is shared between efivars, efivarfs and
efi-pstore, and is long overdue for a makeover.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

parent 5ac94136

Documentation/x86/x86_64/uefi.rst

+1 −1

Original line number	Original line	Diff line number	Diff line
	@@ -29,7 +29,7 @@ Mechanics
	be selected::		be selected::

	CONFIG_EFI=y		CONFIG_EFI=y
	CONFIG_EFI_VARS=y or m # optional		CONFIG_EFIVAR_FS=y or m # optional

	- Create a VFAT partition on the disk		- Create a VFAT partition on the disk
	- Copy the following to the VFAT partition:		- Copy the following to the VFAT partition:

arch/arm/configs/milbeaut_m10v_defconfig

+0 −1

Original line number	Original line	Diff line number	Diff line
	@@ -44,7 +44,6 @@ CONFIG_ARM_CPUIDLE=y
	CONFIG_VFP=y		CONFIG_VFP=y
	CONFIG_NEON=y		CONFIG_NEON=y
	CONFIG_KERNEL_MODE_NEON=y		CONFIG_KERNEL_MODE_NEON=y
	CONFIG_EFI_VARS=m
	CONFIG_EFI_CAPSULE_LOADER=m		CONFIG_EFI_CAPSULE_LOADER=m
	CONFIG_ARM_CRYPTO=y		CONFIG_ARM_CRYPTO=y
	CONFIG_CRYPTO_SHA1_ARM_NEON=m		CONFIG_CRYPTO_SHA1_ARM_NEON=m

arch/ia64/configs/bigsur_defconfig

+0 −1

Original line number	Original line	Diff line number	Diff line
	@@ -10,7 +10,6 @@ CONFIG_SMP=y
	CONFIG_NR_CPUS=2		CONFIG_NR_CPUS=2
	CONFIG_PREEMPT=y		CONFIG_PREEMPT=y
	CONFIG_IA64_PALINFO=y		CONFIG_IA64_PALINFO=y
	CONFIG_EFI_VARS=y
	CONFIG_BINFMT_MISC=m		CONFIG_BINFMT_MISC=m
	CONFIG_ACPI_BUTTON=m		CONFIG_ACPI_BUTTON=m
	CONFIG_ACPI_FAN=m		CONFIG_ACPI_FAN=m

arch/ia64/configs/generic_defconfig

+0 −1

Original line number	Original line	Diff line number	Diff line
	@@ -21,7 +21,6 @@ CONFIG_IA64_MCA_RECOVERY=y
	CONFIG_IA64_PALINFO=y		CONFIG_IA64_PALINFO=y
	CONFIG_KEXEC=y		CONFIG_KEXEC=y
	CONFIG_CRASH_DUMP=y		CONFIG_CRASH_DUMP=y
	CONFIG_EFI_VARS=y
	CONFIG_BINFMT_MISC=m		CONFIG_BINFMT_MISC=m
	CONFIG_ACPI_BUTTON=m		CONFIG_ACPI_BUTTON=m
	CONFIG_ACPI_FAN=m		CONFIG_ACPI_FAN=m

arch/ia64/configs/gensparse_defconfig

+0 −1

Original line number	Original line	Diff line number	Diff line
	@@ -18,7 +18,6 @@ CONFIG_HOTPLUG_CPU=y
	CONFIG_SPARSEMEM_MANUAL=y		CONFIG_SPARSEMEM_MANUAL=y
	CONFIG_IA64_MCA_RECOVERY=y		CONFIG_IA64_MCA_RECOVERY=y
	CONFIG_IA64_PALINFO=y		CONFIG_IA64_PALINFO=y
	CONFIG_EFI_VARS=y
	CONFIG_BINFMT_MISC=m		CONFIG_BINFMT_MISC=m
	CONFIG_ACPI_BUTTON=m		CONFIG_ACPI_BUTTON=m
	CONFIG_ACPI_FAN=m		CONFIG_ACPI_FAN=m