efi: Bump stub image version for macOS HVF compatibility

The macOS hypervisor framework includes a host-side VMM called
VZLinuxBootLoader [1] which implements native support for booting the
Linux kernel inside a guest directly (instead of, e.g., via GRUB
installed inside the guest). On x86, it incorporates a BIOS style loader
that does not implement or expose EFI to the loaded kernel. However,
this loader appears to fail when the 'image minor version' field in the
kernel image's PE/COFF header (which is generally only used by EFI based
bootloaders) is set to any value other than 0x0. [2]

Commit e346bebbd36b1576 ("efi: libstub: Always enable initrd command
line loader and bump version") incremented the EFI stub image minor
version to convey that all EFI stub kernels now implement support for
the initrd= command line option, and do so in a way where it can load
initrd images from any filesystem known to the EFI firmware (as opposed
to prior implementations that could only load initrds from the same
volume that the kernel image was loaded from).

Unfortunately, bumping the version to v1.1 triggers this issue in
VZLinuxBootLoader, breaking the boot on x86. So let's keep the image
minor version at 0x0, and bump the image major version instead.

While at it, convert this field to a bit field, so that individual
features are discoverable from it, as suggested by Linus. So let's bump
the major version to v3, and document the initrd= command line loading
feature as being represented by bit 1 in the mask.

Note that, due to the prior interpretation as a monotonically increasing
version field, loaders are still permitted to assume that the LoadFile2
initrd loading feature is supported for any major version value >= 1,
even if bit 0 is not set.

[1] https://developer.apple.com/documentation/virtualization/vzlinuxbootloader
[2] https://lore.kernel.org/linux-efi/CAG8fp8Teu4G9JuenQrqGndFt2Gy+V4YgJ=hN1xX7AD940YKf3A@mail.gmail.com/

Fixes: e346bebbd36b1576 ("efi: libstub: Always enable initrd command ...")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217485
Signed-off-by: Akihiro Suda <suda.kyoto@gmail.com>
[ardb: rewrite comment and commit log]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi/pe: Import new BTI/IBT header flags from the spec

The latest version of your favorite fork of the PE/COFF spec includes a
new type of header flag that is intended to be used in the context of
EFI firmware to indicate to the image loader that the executable regions
of an image can be mapped with BTI/IBT enforcement enabled.

So let's import these definitions so we can use them in subsequent
patches.

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

efi: Put Linux specific magic number in the DOS header

GRUB currently relies on the magic number in the image header of ARM and
arm64 EFI kernel images to decide whether or not the image in question
is a bootable kernel.

However, the purpose of the magic number is to identify the image as one
that implements the bare metal boot protocol, and so GRUB, which only
does EFI boot, is limited unnecessarily to booting images that could
potentially be booted in a non-EFI manner as well.

This is problematic for the new zboot decompressor image format, as it
can only boot in EFI mode, and must therefore not use the bare metal
boot magic number in its header.

For this reason, the strict magic number was dropped from GRUB, to
permit essentially any kind of EFI executable to be booted via the
'linux' command, blurring the line between the linux loader and the
chainloader.

So let's use the same field in the DOS header that RISC-V and arm64
already use for their 'bare metal' magic numbers to store a 'generic
Linux kernel' magic number, which can be used to identify bootable
kernel images in PE format which don't necessarily implement a bare
metal boot protocol in the same binary. Note that, in the context of
EFI, the MS-DOS header is only described in terms of the fields that it
shares with the hybrid PE/COFF image format, (i.e., the MS-DOS EXE magic
number at offset #0 and the PE header offset at byte offset #0x3c).
Since we aim for compatibility with EFI only, and not with MS-DOS or
MS-Windows, we can use the remaining space in the MS-DOS header however
we want.

Let's set the generic magic number for x86 images as well: existing
bootloaders already have their own methods to identify x86 Linux images
that can be booted in a non-EFI manner, and having the magic number in
place there will ease any future transitions in loader implementations
to merge the x86 and non-x86 EFI boot paths.

Note that 32-bit ARM already uses the same location in the header for a
different purpose, but the ARM support is already widely implemented and
the EFI zboot decompressor is not available on ARM anyway, so we just
disregard it here.

Acked-by: Leif Lindholm <quic_llindhol@quicinc.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi: libstub: Always enable initrd command line loader and bump version

In preparation for setting a cross-architecture baseline for EFI boot
support, remove the Kconfig option that permits the command line initrd
loader to be disabled. Also, bump the minor version so that any image
built with the new version can be identified as supporting this.

Acked-by: Leif Lindholm <quic_llindhol@quicinc.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi/loongarch: Add efistub booting support

This patch adds efistub booting support, which is the standard UEFI boot
protocol for LoongArch to use.

We use generic efistub, which means we can pass boot information (i.e.,
system table, memory map, kernel command line, initrd) via a light FDT
and drop a lot of non-standard code.

We use a flat mapping to map the efi runtime in the kernel's address
space. In efi, VA = PA; in kernel, VA = PA + PAGE_OFFSET. As a result,
flat mapping is not identity mapping, SetVirtualAddressMap() is still
needed for the efi runtime.

Tested-by: Xi Ruoyao <xry111@xry111.site>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
[ardb: change fpic to fpie as suggested by Xi Ruoyao]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

include: pe.h: Add RISC-V related PE definition

Define RISC-V related machine types.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Link: https://lore.kernel.org/r/20200415195422.19866-3-atish.patra@wdc.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

efi: Bump the Linux EFI stub major version number to #1

Now that we have introduced new, generic ways for the OS loader to
interface with Linux kernels during boot, we need to record this
fact in a way that allows loaders to discover this information, and
fall back to the existing methods for older kernels.

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

efi/libstub: Introduce symbolic constants for the stub major/minor version

Now that we have added new ways to load the initrd or the mixed mode
kernel, we will also need a way to tell the loader about this. Add
symbolic constants for the PE/COFF major/minor version numbers (which
fortunately have always been 0x0 for all architectures), so that we
can bump them later to document the capabilities of the stub.

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

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 340

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation version 2 of the license this program
is distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not see http www gnu org
licenses

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 15 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000437.052642892@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

include: pe.h: remove message[] from mz header definition

message[] field won't be part of the definition of mz header.

This change is crucial for enabling kexec_file_load on arm64 because
arm64's "Image" binary, as in PE format, doesn't have any data for it and
accordingly the following check in pefile_parse_binary() will fail:

chkaddr(cursor, mz->peaddr, sizeof(*pe));

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Will Deacon <will.deacon@arm.com>

include: pe.h: add some missing definitions

Add the missing IMAGE_FILE_MACHINE_ARM64 and IMAGE_DEBUG_TYPE_CODEVIEW
definitions.

We'll need them for the arm64 EFI stub...

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
[ardb: add IMAGE_DEBUG_TYPE_CODEVIEW as well]
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

include: pe.h: allow for use in assembly

Some of the definitions in include/linux/pe.h would be useful for the
EFI stub headers, where values are currently open-coded. Unfortunately
they cannot be used as some structures are also defined in pe.h without
!__ASSEMBLY__ guards.

This patch moves the structure definitions into an #ifdef __ASSEMBLY__
block, so that the common value definitions can be used from assembly.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

Provide PE binary definitions

Provide some PE binary structural and constant definitions as taken from the
pesign package sources.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>