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path: root/drivers/firmware/efi/Kconfig
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2025-06-21x86/efi: Implement support for embedding SBAT data for x86Vitaly Kuznetsov
Similar to zboot architectures, implement support for embedding SBAT data for x86. Put '.sbat' section in between '.data' and '.text' as the former also covers '.bss' and '.pgtable' and thus must be the last one in the file. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/20250603091951.57775-1-vkuznets@redhat.com
2025-05-21efi: zboot specific mechanism for embedding SBAT sectionVitaly Kuznetsov
SBAT is a mechanism which improves SecureBoot revocations of UEFI binaries by introducing a generation-based technique. Compromised or vulnerable UEFI binaries can be prevented from booting by bumping the minimal required generation for the specific component in the bootloader. More information on the SBAT can be obtained here: https://github.com/rhboot/shim/blob/main/SBAT.md Upstream Linux kernel does not currently participate in any way in SBAT as there's no existing policy in how SBAT generation number should be defined. Keep the status quo and provide a mechanism for distro vendors and anyone else who signs their kernel for SecureBoot to include their own SBAT data. This leaves the decision on the policy to the vendor. Basically, each distro implementing SecureBoot today, will have an option to inject their own SBAT data during kernel build and before it gets signed by their SecureBoot CA. Different distro do not need to agree on the common SBAT component names or generation numbers as each distro ships its own 'shim' with their own 'vendor_cert'/'vendor_db' Implement support for embedding SBAT data for architectures using zboot (arm64, loongarch, riscv). Put '.sbat' section in between '.data' and '.text' as the former also covers '.bss' and thus must be the last one. Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-12-06efi/zboot: Limit compression options to GZIP and ZSTDArd Biesheuvel
For historical reasons, the legacy decompressor code on various architectures supports 7 different compression types for the compressed kernel image. EFI zboot is not a compression library museum, and so the options can be limited to what is likely to be useful in practice: - GZIP is tried and tested, and is still one of the fastest at decompression time, although the compression ratio is not very high; moreover, Fedora is already shipping EFI zboot kernels for arm64 that use GZIP, and QEMU implements direct support for it when booting a kernel without firmware loaded; - ZSTD has a very high compression ratio (although not the highest), and is almost as fast as GZIP at decompression time. Reducing the number of options makes it less of a hassle for other consumers of the EFI zboot format (such as QEMU today, and kexec in the future) to support it transparently without having to carry 7 different decompression libraries. Acked-by: Gerd Hoffmann <kraxel@redhat.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2024-11-15efi/zboot: Fix outdated comment about using LoadImage/StartImageArd Biesheuvel
EFI zboot no longer uses LoadImage/StartImage, but subsumes the arch code to load and start the bare metal image directly. Fix the Kconfig description accordingly. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2023-12-11efi: Add tee-based EFI variable driverMasahisa Kojima
When the flash is not owned by the non-secure world, accessing the EFI variables is straight-forward and done via EFI Runtime Variable Services. In this case, critical variables for system integrity and security are normally stored in the dedicated secure storage and can only be manipulated directly from the secure world. Usually, small embedded devices don't have the special dedicated secure storage. The eMMC device with an RPMB partition is becoming more common, and we can use this RPMB partition to store the EFI Variables. The eMMC device is typically owned by the non-secure world (Linux in our case). There is an existing solution utilizing eMMC RPMB partition for EFI Variables, it is implemented by interacting with TEE (OP-TEE in this case), StandaloneMM (as EFI Variable Service Pseudo TA), eMMC driver and tee-supplicant. The last piece is the tee-based variable access driver to interact with TEE and StandaloneMM. So let's add the kernel functions needed. This feature is implemented as a kernel module. StMM PTA has TA_FLAG_DEVICE_ENUM_SUPP flag when registered to OP-TEE so that this tee_stmm_efi module is probed after tee-supplicant starts, since "SetVariable" EFI Runtime Variable Service requires to interact with tee-supplicant. Acked-by: Sumit Garg <sumit.garg@linaro.org> Co-developed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2023-09-11arch: Remove Itanium (IA-64) architectureArd Biesheuvel
The Itanium architecture is obsolete, and an informal survey [0] reveals that any residual use of Itanium hardware in production is mostly HP-UX or OpenVMS based. The use of Linux on Itanium appears to be limited to enthusiasts that occasionally boot a fresh Linux kernel to see whether things are still working as intended, and perhaps to churn out some distro packages that are rarely used in practice. None of the original companies behind Itanium still produce or support any hardware or software for the architecture, and it is listed as 'Orphaned' in the MAINTAINERS file, as apparently, none of the engineers that contributed on behalf of those companies (nor anyone else, for that matter) have been willing to support or maintain the architecture upstream or even be responsible for applying the odd fix. The Intel firmware team removed all IA-64 support from the Tianocore/EDK2 reference implementation of EFI in 2018. (Itanium is the original architecture for which EFI was developed, and the way Linux supports it deviates significantly from other architectures.) Some distros, such as Debian and Gentoo, still maintain [unofficial] ia64 ports, but many have dropped support years ago. While the argument is being made [1] that there is a 'for the common good' angle to being able to build and run existing projects such as the Grid Community Toolkit [2] on Itanium for interoperability testing, the fact remains that none of those projects are known to be deployed on Linux/ia64, and very few people actually have access to such a system in the first place. Even if there were ways imaginable in which Linux/ia64 could be put to good use today, what matters is whether anyone is actually doing that, and this does not appear to be the case. There are no emulators widely available, and so boot testing Itanium is generally infeasible for ordinary contributors. GCC still supports IA-64 but its compile farm [3] no longer has any IA-64 machines. GLIBC would like to get rid of IA-64 [4] too because it would permit some overdue code cleanups. In summary, the benefits to the ecosystem of having IA-64 be part of it are mostly theoretical, whereas the maintenance overhead of keeping it supported is real. So let's rip off the band aid, and remove the IA-64 arch code entirely. This follows the timeline proposed by the Debian/ia64 maintainer [5], which removes support in a controlled manner, leaving IA-64 in a known good state in the most recent LTS release. Other projects will follow once the kernel support is removed. [0] https://lore.kernel.org/all/CAMj1kXFCMh_578jniKpUtx_j8ByHnt=s7S+yQ+vGbKt9ud7+kQ@mail.gmail.com/ [1] https://lore.kernel.org/all/0075883c-7c51-00f5-2c2d-5119c1820410@web.de/ [2] https://gridcf.org/gct-docs/latest/index.html [3] https://cfarm.tetaneutral.net/machines/list/ [4] https://lore.kernel.org/all/87bkiilpc4.fsf@mid.deneb.enyo.de/ [5] https://lore.kernel.org/all/ff58a3e76e5102c94bb5946d99187b358def688a.camel@physik.fu-berlin.de/ Acked-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2023-06-06efi/libstub: Implement support for unaccepted memoryKirill A. Shutemov
UEFI Specification version 2.9 introduces the concept of memory acceptance: Some Virtual Machine platforms, such as Intel TDX or AMD SEV-SNP, requiring memory to be accepted before it can be used by the guest. Accepting happens via a protocol specific for the Virtual Machine platform. Accepting memory is costly and it makes VMM allocate memory for the accepted guest physical address range. It's better to postpone memory acceptance until memory is needed. It lowers boot time and reduces memory overhead. The kernel needs to know what memory has been accepted. Firmware communicates this information via memory map: a new memory type -- EFI_UNACCEPTED_MEMORY -- indicates such memory. Range-based tracking works fine for firmware, but it gets bulky for the kernel: e820 (or whatever the arch uses) has to be modified on every page acceptance. It leads to table fragmentation and there's a limited number of entries in the e820 table. Another option is to mark such memory as usable in e820 and track if the range has been accepted in a bitmap. One bit in the bitmap represents a naturally aligned power-2-sized region of address space -- unit. For x86, unit size is 2MiB: 4k of the bitmap is enough to track 64GiB or physical address space. In the worst-case scenario -- a huge hole in the middle of the address space -- It needs 256MiB to handle 4PiB of the address space. Any unaccepted memory that is not aligned to unit_size gets accepted upfront. The bitmap is allocated and constructed in the EFI stub and passed down to the kernel via EFI configuration table. allocate_e820() allocates the bitmap if unaccepted memory is present, according to the size of unaccepted region. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20230606142637.5171-4-kirill.shutemov@linux.intel.com
2022-12-01efi: libstub: Always enable initrd command line loader and bump versionArd Biesheuvel
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>
2022-11-18efi: x86: Move EFI runtime map sysfs code to arch/x86Ard Biesheuvel
The EFI runtime map code is only wired up on x86, which is the only architecture that has a need for it in its implementation of kexec. So let's move this code under arch/x86 and drop all references to it from generic code. To ensure that the efi_runtime_map_init() is invoked at the appropriate time use a 'sync' subsys_initcall() that will be called right after the EFI initcall made from generic code where the original invocation of efi_runtime_map_init() resided. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Dave Young <dyoung@redhat.com>
2022-11-18efi: runtime-maps: Clarify purpose and enable by default for kexecArd Biesheuvel
The current Kconfig logic for CONFIG_EFI_RUNTIME_MAPS does not convey that without it, a kexec kernel is not able to boot in EFI mode at all. So clarify this, and make the option only configurable via the menu system if CONFIG_EXPERT is set. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Dave Young <dyoung@redhat.com>
2022-11-18efi: memmap: Move EFI fake memmap support into x86 arch treeArd Biesheuvel
The EFI fake memmap support is specific to x86, which manipulates the EFI memory map in various different ways after receiving it from the EFI stub. On other architectures, we have managed to push back on this, and the EFI memory map is kept pristine. So let's move the fake memmap code into the x86 arch tree, where it arguably belongs. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-11-18efi: libstub: Undeprecate the command line initrd loaderArd Biesheuvel
The initrd= command line loader can be useful for development, but it was limited to loading files from the same file system as the loaded kernel (and it didn't work on x86 mixed mode). As both issues have been fixed, and the initrd= can now be used with files residing on any simple file system exposed by the EFI firmware, let's permit it to be enabled on RISC-V and LoongArch, which did not support it up to this point. Note that LoadFile2 remains the preferred option, as it is much simpler to use and implement, but generic loaders (including the UEFI shell) may not implement this so there, initrd= can now be used as well (if enabled in the build) Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-10-21efi: libstub: Remove zboot signing from build optionsArd Biesheuvel
The zboot decompressor series introduced a feature to sign the PE/COFF kernel image for secure boot as part of the kernel build. This was necessary because there are actually two images that need to be signed: the kernel with the EFI stub attached, and the decompressor application. This is a bit of a burden, because it means that the images must be signed on the the same system that performs the build, and this is not realistic for distros. During the next cycle, we will introduce changes to the zboot code so that the inner image no longer needs to be signed. This means that the outer PE/COFF image can be handled as usual, and be signed later in the release process. Let's remove the associated Kconfig options now so that they don't end up in a LTS release while already being deprecated. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-09-20efi/libstub: implement generic EFI zbootArd Biesheuvel
Implement a minimal EFI app that decompresses the real kernel image and launches it using the firmware's LoadImage and StartImage boot services. This removes the need for any arch-specific hacks. Note that on systems that have UEFI secure boot policies enabled, LoadImage/StartImage require images to be signed, or their hashes known a priori, in order to be permitted to boot. There are various possible strategies to work around this requirement, but they all rely either on overriding internal PI/DXE protocols (which are not part of the EFI spec) or omitting the firmware provided LoadImage() and StartImage() boot services, which is also undesirable, given that they encapsulate platform specific policies related to secure boot and measured boot, but also related to memory permissions (whether or not and which types of heap allocations have both write and execute permissions.) The only generic and truly portable way around this is to simply sign both the inner and the outer image with the same key/cert pair, so this is what is implemented here. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-09-06efi/loongarch: Add efistub booting supportHuacai Chen
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>
2022-06-24efi: vars: Remove deprecated 'efivars' sysfs interfaceArd Biesheuvel
Commit 5d9db883761a ("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>
2022-06-24efi: pstore: Omit efivars caching EFI varstore access layerArd Biesheuvel
Avoid the efivars layer and simply call the newly introduced EFI varstore helpers instead. This simplifies the code substantially, and also allows us to remove some hacks in the shared efivars layer that were added for efi-pstore specifically. In order to be able to delete the EFI variable associated with a record, store the UTF-16 name of the variable in the pstore record's priv field. That way, we don't have to make guesses regarding which variable the record may have been loaded from. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-06-20efi: efibc: avoid efivar API for setting variablesArd Biesheuvel
Avoid abusing the efivar API by passing locally instantiated efivar_entry structs into efivar_set_entry_safe(), rather than using the API as intended. Instead, just call efi.set_variable() directly. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-06-01efi: clean up Kconfig dependencies on CONFIG_EFIArd Biesheuvel
Geert reports that the new option CONFIG_EFI_DISABLE_RUNTIME is user visible even when EFI support is disabled, which is unnecessary and clutters the Kconfig interface. So let's move this option into the existing Kconfig submenu that already depends on CONFIG_EFI, and while at it, give some other options the same treatment. Also clean up a small wart where the efi/ subdirectory is listed twice. Let's just list it unconditionally so that both EFI and UEFI_CPER based pieces will be built independently (the latter only depends on the former on !X86) Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-05-03efi: libstub: ensure allocated memory to be executableBaskov Evgeniy
There are UEFI versions that restrict execution of memory regions, preventing the kernel from booting. Parts that needs to be executable are: * Area used for trampoline placement. * All memory regions that the kernel may be relocated before and during extraction. Use DXE services to ensure aforementioned address ranges to be executable. Only modify attributes that does not have appropriate attributes. Signed-off-by: Baskov Evgeniy <baskov@ispras.ru> Link: https://lore.kernel.org/r/20220303142120.1975-3-baskov@ispras.ru Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-04-13efi: Save location of EFI confidential computing areaDov Murik
Confidential computing (coco) hardware such as AMD SEV (Secure Encrypted Virtualization) allows a guest owner to inject secrets into the VMs memory without the host/hypervisor being able to read them. Firmware support for secret injection is available in OVMF, which reserves a memory area for secret injection and includes a pointer to it the in EFI config table entry LINUX_EFI_COCO_SECRET_TABLE_GUID. If EFI exposes such a table entry, uefi_init() will keep a pointer to the EFI config table entry in efi.coco_secret, so it can be used later by the kernel (specifically drivers/virt/coco/efi_secret). It will also appear in the kernel log as "CocoSecret=ADDRESS"; for example: [ 0.000000] efi: EFI v2.70 by EDK II [ 0.000000] efi: CocoSecret=0x7f22e680 SMBIOS=0x7f541000 ACPI=0x7f77e000 ACPI 2.0=0x7f77e014 MEMATTR=0x7ea0c018 The new functionality can be enabled with CONFIG_EFI_COCO_SECRET=y. Signed-off-by: Dov Murik <dovmurik@linux.ibm.com> Reviewed-by: Gerd Hoffmann <kraxel@redhat.com> Link: https://lore.kernel.org/r/20220412212127.154182-2-dovmurik@linux.ibm.com Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2022-04-13efi: Allow to enable EFI runtime services by default on RTJavier Martinez Canillas
Commit d9f283ae71af ("efi: Disable runtime services on RT") disabled EFI runtime services by default when the CONFIG_PREEMPT_RT option is enabled. The rationale for that commit is that some EFI calls could take too much time, leading to large latencies which is an issue for Real-Time kernels. But a side effect of that change was that now is not possible anymore to enable the EFI runtime services by default when CONFIG_PREEMPT_RT is set, without passing an efi=runtime command line parameter to the kernel. Instead, let's add a new EFI_DISABLE_RUNTIME boolean Kconfig option, that would be set to n by default but to y if CONFIG_PREEMPT_RT is enabled. That way, the current behaviour is preserved but gives users a mechanism to enable the EFI runtimes services in their kernels if that is required. For example, if the firmware could guarantee bounded time for EFI calls. Also, having a separate boolean config could allow users to disable the EFI runtime services by default even when CONFIG_PREEMPT_RT is not set. Reported-by: Alexander Larsson <alexl@redhat.com> Fixes: d9f283ae71af ("efi: Disable runtime services on RT") Signed-off-by: Javier Martinez Canillas <javierm@redhat.com> Link: https://lore.kernel.org/r/20220331151654.184433-1-javierm@redhat.com Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-12-24Merge tag 'efi_updates_for_v5.11' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull EFI updates from Borislav Petkov: "These got delayed due to a last minute ia64 build issue which got fixed in the meantime. EFI updates collected by Ard Biesheuvel: - Don't move BSS section around pointlessly in the x86 decompressor - Refactor helper for discovering the EFI secure boot mode - Wire up EFI secure boot to IMA for arm64 - Some fixes for the capsule loader - Expose the RT_PROP table via the EFI test module - Relax DT and kernel placement restrictions on ARM with a few followup fixes: - fix the build breakage on IA64 caused by recent capsule loader changes - suppress a type mismatch build warning in the expansion of EFI_PHYS_ALIGN on ARM" * tag 'efi_updates_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: efi: arm: force use of unsigned type for EFI_PHYS_ALIGN efi: ia64: disable the capsule loader efi: stub: get rid of efi_get_max_fdt_addr() efi/efi_test: read RuntimeServicesSupported efi: arm: reduce minimum alignment of uncompressed kernel efi: capsule: clean scatter-gather entries from the D-cache efi: capsule: use atomic kmap for transient sglist mappings efi: x86/xen: switch to efi_get_secureboot_mode helper arm64/ima: add ima_arch support ima: generalize x86/EFI arch glue for other EFI architectures efi: generalize efi_get_secureboot efi/libstub: EFI_GENERIC_STUB_INITRD_CMDLINE_LOADER should not default to yes efi/x86: Only copy the compressed kernel image in efi_relocate_kernel() efi/libstub/x86: simplify efi_is_native()
2020-12-14efi: ia64: disable the capsule loaderArd Biesheuvel
EFI capsule loading is a feature that was introduced into EFI long after its initial introduction on Itanium, and it is highly unlikely that IA64 systems are receiving firmware updates in the first place, let alone using EFI capsules. So let's disable capsule support altogether on IA64. This fixes a build error on IA64 due to a recent change that added an unconditional include of asm/efi.h, which IA64 does not provide. While at it, tweak the make rules a bit so that the EFI capsule component that is always builtin (even if the EFI capsule loader itself is built as a module) is omitted for all architectures if the module is not enabled in the build. Cc: Tony Luck <tony.luck@intel.com> Link: https://lore.kernel.org/linux-efi/20201214152200.38353-1-ardb@kernel.org Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-11-25efi: EFI_EARLYCON should depend on EFIGeert Uytterhoeven
CONFIG_EFI_EARLYCON defaults to yes, and thus is enabled on systems that do not support EFI, or do not have EFI support enabled, but do satisfy the symbol's other dependencies. While drivers/firmware/efi/ won't be entered during the build phase if CONFIG_EFI=n, and drivers/firmware/efi/earlycon.c itself thus won't be built, enabling EFI_EARLYCON does force-enable CONFIG_FONT_SUPPORT and CONFIG_ARCH_USE_MEMREMAP_PROT, and CONFIG_FONT_8x16, which is undesirable. Fix this by making CONFIG_EFI_EARLYCON depend on CONFIG_EFI. This reduces kernel size on headless systems by more than 4 KiB. Fixes: 69c1f396f25b805a ("efi/x86: Convert x86 EFI earlyprintk into generic earlycon implementation") Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Link: https://lore.kernel.org/r/20201124191646.3559757-1-geert@linux-m68k.org Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-10-29efi/libstub: EFI_GENERIC_STUB_INITRD_CMDLINE_LOADER should not default to yesGeert Uytterhoeven
EFI_GENERIC_STUB_INITRD_CMDLINE_LOADER is deprecated, so it should not be enabled by default. In light of commit 4da0b2b7e67524cc ("efi/libstub: Re-enable command line initrd loading for x86"), keep the default for X86. Fixes: cf6b83664895a5c7 ("efi/libstub: Make initrd file loader configurable") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/20201028153402.1736103-1-geert+renesas@glider.be Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-10-19Merge tag 'riscv-for-linus-5.10-mw0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: "A handful of cleanups and new features: - A handful of cleanups for our page fault handling - Improvements to how we fill out cacheinfo - Support for EFI-based systems" * tag 'riscv-for-linus-5.10-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (22 commits) RISC-V: Add page table dump support for uefi RISC-V: Add EFI runtime services RISC-V: Add EFI stub support. RISC-V: Add PE/COFF header for EFI stub RISC-V: Implement late mapping page table allocation functions RISC-V: Add early ioremap support RISC-V: Move DT mapping outof fixmap RISC-V: Fix duplicate included thread_info.h riscv/mm/fault: Set FAULT_FLAG_INSTRUCTION flag in do_page_fault() riscv/mm/fault: Fix inline placement in vmalloc_fault() declaration riscv: Add cache information in AUX vector riscv: Define AT_VECTOR_SIZE_ARCH for ARCH_DLINFO riscv: Set more data to cacheinfo riscv/mm/fault: Move access error check to function riscv/mm/fault: Move FAULT_FLAG_WRITE handling in do_page_fault() riscv/mm/fault: Simplify mm_fault_error() riscv/mm/fault: Move fault error handling to mm_fault_error() riscv/mm/fault: Simplify fault error handling riscv/mm/fault: Move vmalloc fault handling to vmalloc_fault() riscv/mm/fault: Move bad area handling to bad_area() ...
2020-10-02RISC-V: Add EFI stub support.Atish Patra
Add a RISC-V architecture specific stub code that actually copies the actual kernel image to a valid address and jump to it after boot services are terminated. Enable UEFI related kernel configs as well for RISC-V. Signed-off-by: Atish Patra <atish.patra@wdc.com> Link: https://lore.kernel.org/r/20200421033336.9663-4-atish.patra@wdc.com [ardb: - move hartid fetch into check_platform_features() - use image_size not reserve_size - select ISA_C - do not use dram_base] Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-09-29efi: efivars: limit availability to X86 buildsArd Biesheuvel
CONFIG_EFI_VARS controls the code that exposes EFI variables via sysfs entries, which was deprecated before support for non-Intel architectures was added to EFI. So let's limit its availability to Intel architectures for the time being, and hopefully remove it entirely in the not too distant future. While at it, let's remove the module alias so that the module is no longer loaded automatically. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-09-29efi: remove some false dependencies on CONFIG_EFI_VARSArd Biesheuvel
Remove some false dependencies on CONFIG_EFI_VARS, which only controls the creation of the sysfs entries, whereas the underlying functionality that these modules rely on is enabled unconditionally when CONFIG_EFI is set. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-09-29efi: pstore: disentangle from deprecated efivars moduleArd Biesheuvel
The EFI pstore implementation relies on the 'efivars' abstraction, which encapsulates the EFI variable store in a way that can be overridden by other backing stores, like the Google SMI one. On top of that, the EFI pstore implementation also relies on the efivars.ko module, which is a separate layer built on top of the 'efivars' abstraction that exposes the [deprecated] sysfs entries for each variable that exists in the backing store. Since the efivars.ko module is deprecated, and all users appear to have moved to the efivarfs file system instead, let's prepare for its removal, by removing EFI pstore's dependency on it. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-06-16efi: Make it possible to disable efivar_ssdt entirelyPeter Jones
In most cases, such as CONFIG_ACPI_CUSTOM_DSDT and CONFIG_ACPI_TABLE_UPGRADE, boot-time modifications to firmware tables are tied to specific Kconfig options. Currently this is not the case for modifying the ACPI SSDT via the efivar_ssdt kernel command line option and associated EFI variable. This patch adds CONFIG_EFI_CUSTOM_SSDT_OVERLAYS, which defaults disabled, in order to allow enabling or disabling that feature during the build. Cc: <stable@vger.kernel.org> Signed-off-by: Peter Jones <pjones@redhat.com> Link: https://lore.kernel.org/r/20200615202408.2242614-1-pjones@redhat.com Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-06-14treewide: replace '---help---' in Kconfig files with 'help'Masahiro Yamada
Since commit 84af7a6194e4 ("checkpatch: kconfig: prefer 'help' over '---help---'"), the number of '---help---' has been gradually decreasing, but there are still more than 2400 instances. This commit finishes the conversion. While I touched the lines, I also fixed the indentation. There are a variety of indentation styles found. a) 4 spaces + '---help---' b) 7 spaces + '---help---' c) 8 spaces + '---help---' d) 1 space + 1 tab + '---help---' e) 1 tab + '---help---' (correct indentation) f) 1 tab + 1 space + '---help---' g) 1 tab + 2 spaces + '---help---' In order to convert all of them to 1 tab + 'help', I ran the following commend: $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/' Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-04-25efi/libstub: Re-enable command line initrd loading for x86Ard Biesheuvel
Commit: cf6b83664895a5 ("efi/libstub: Make initrd file loader configurable") inadvertently disabled support on x86 for loading an initrd passed via the initrd= option on the kernel command line. Add X86 to the newly introduced Kconfig option's title and depends declarations, so it gets enabled by default, as before. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: linux-efi@vger.kernel.org
2020-04-23efi/libstub: Make initrd file loader configurableArd Biesheuvel
Loading an initrd passed via the kernel command line is deprecated: it is limited to files that reside in the same volume as the one the kernel itself was loaded from, and we have more flexible ways to achieve the same. So make it configurable so new architectures can decide not to enable it. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-04-23efi/libstub: Move arm-stub to a common fileAtish Patra
Most of the arm-stub code is written in an architecture independent manner. As a result, RISC-V can reuse most of the arm-stub code. Rename the arm-stub.c to efi-stub.c so that ARM, ARM64 and RISC-V can use it. This patch doesn't introduce any functional changes. Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Link: https://lore.kernel.org/r/20200415195422.19866-2-atish.patra@wdc.com Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-03-03efi: Add embedded peripheral firmware supportHans de Goede
Just like with PCI options ROMs, which we save in the setup_efi_pci* functions from arch/x86/boot/compressed/eboot.c, the EFI code / ROM itself sometimes may contain data which is useful/necessary for peripheral drivers to have access to. Specifically the EFI code may contain an embedded copy of firmware which needs to be (re)loaded into the peripheral. Normally such firmware would be part of linux-firmware, but in some cases this is not feasible, for 2 reasons: 1) The firmware is customized for a specific use-case of the chipset / use with a specific hardware model, so we cannot have a single firmware file for the chipset. E.g. touchscreen controller firmwares are compiled specifically for the hardware model they are used with, as they are calibrated for a specific model digitizer. 2) Despite repeated attempts we have failed to get permission to redistribute the firmware. This is especially a problem with customized firmwares, these get created by the chip vendor for a specific ODM and the copyright may partially belong with the ODM, so the chip vendor cannot give a blanket permission to distribute these. This commit adds support for finding peripheral firmware embedded in the EFI code and makes the found firmware available through the new efi_get_embedded_fw() function. Support for loading these firmwares through the standard firmware loading mechanism is added in a follow-up commit in this patch-series. Note we check the EFI_BOOT_SERVICES_CODE for embedded firmware near the end of start_kernel(), just before calling rest_init(), this is on purpose because the typical EFI_BOOT_SERVICES_CODE memory-segment is too large for early_memremap(), so the check must be done after mm_init(). This relies on EFI_BOOT_SERVICES_CODE not being free-ed until efi_free_boot_services() is called, which means that this will only work on x86 for now. Reported-by: Dave Olsthoorn <dave@bewaar.me> Suggested-by: Peter Jones <pjones@redhat.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20200115163554.101315-3-hdegoede@redhat.com Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-01-10efi: Allow disabling PCI busmastering on bridges during bootMatthew Garrett
Add an option to disable the busmaster bit in the control register on all PCI bridges before calling ExitBootServices() and passing control to the runtime kernel. System firmware may configure the IOMMU to prevent malicious PCI devices from being able to attack the OS via DMA. However, since firmware can't guarantee that the OS is IOMMU-aware, it will tear down IOMMU configuration when ExitBootServices() is called. This leaves a window between where a hostile device could still cause damage before Linux configures the IOMMU again. If CONFIG_EFI_DISABLE_PCI_DMA is enabled or "efi=disable_early_pci_dma" is passed on the command line, the EFI stub will clear the busmaster bit on all PCI bridges before ExitBootServices() is called. This will prevent any malicious PCI devices from being able to perform DMA until the kernel reenables busmastering after configuring the IOMMU. This option may cause failures with some poorly behaved hardware and should not be enabled without testing. The kernel commandline options "efi=disable_early_pci_dma" or "efi=no_disable_early_pci_dma" may be used to override the default. Note that PCI devices downstream from PCI bridges are disconnected from their drivers first, using the UEFI driver model API, so that DMA can be disabled safely at the bridge level. [ardb: disconnect PCI I/O handles first, as suggested by Arvind] Co-developed-by: Matthew Garrett <mjg59@google.com> Signed-off-by: Matthew Garrett <mjg59@google.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Matthew Garrett <matthewgarrett@google.com> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20200103113953.9571-18-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-07efi: Common enable/disable infrastructure for EFI soft reservationDan Williams
UEFI 2.8 defines an EFI_MEMORY_SP attribute bit to augment the interpretation of the EFI Memory Types as "reserved for a specific purpose". The proposed Linux behavior for specific purpose memory is that it is reserved for direct-access (device-dax) by default and not available for any kernel usage, not even as an OOM fallback. Later, through udev scripts or another init mechanism, these device-dax claimed ranges can be reconfigured and hot-added to the available System-RAM with a unique node identifier. This device-dax management scheme implements "soft" in the "soft reserved" designation by allowing some or all of the reservation to be recovered as typical memory. This policy can be disabled at compile-time with CONFIG_EFI_SOFT_RESERVE=n, or runtime with efi=nosoftreserve. As for this patch, define the common helpers to determine if the EFI_MEMORY_SP attribute should be honored. The determination needs to be made early to prevent the kernel from being loaded into soft-reserved memory, or otherwise allowing early allocations to land there. Follow-on changes are needed per architecture to leverage these helpers in their respective mem-init paths. Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-31efi: Make CONFIG_EFI_RCI2_TABLE selectable on x86 onlyNarendra K
For the EFI_RCI2_TABLE Kconfig option, 'make oldconfig' asks the user for input on platforms where the option may not be applicable. This patch modifies the Kconfig option to ask the user for input only when CONFIG_X86 or CONFIG_COMPILE_TEST is set to y. Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Narendra K <Narendra.K@dell.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191029173755.27149-2-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-08-08efi: Export Runtime Configuration Interface table to sysfsNarendra K
System firmware advertises the address of the 'Runtime Configuration Interface table version 2 (RCI2)' via an EFI Configuration Table entry. This code retrieves the RCI2 table from the address and exports it to sysfs as a binary attribute 'rci2' under /sys/firmware/efi/tables directory. The approach adopted is similar to the attribute 'DMI' under /sys/firmware/dmi/tables. RCI2 table contains BIOS HII in XML format and is used to populate BIOS setup page in Dell EMC OpenManage Server Administrator tool. The BIOS setup page contains BIOS tokens which can be configured. Signed-off-by: Narendra K <Narendra.K@dell.com> Reviewed-by: Mario Limonciello <mario.limonciello@dell.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2019-05-21treewide: Add SPDX license identifier - Makefile/KconfigThomas Gleixner
Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-04efi/x86: Convert x86 EFI earlyprintk into generic earlycon implementationArd Biesheuvel
Move the x86 EFI earlyprintk implementation to a shared location under drivers/firmware and tweak it slightly so we can expose it as an earlycon implementation (which is generic) rather than earlyprintk (which is only implemented for a few architectures) This also involves switching to write-combine mappings by default (which is required on ARM since device mappings lack memory semantics, and so memcpy/memset may not be used on them), and adding support for shared memory framebuffers on cache coherent non-x86 systems (which do not tolerate mismatched attributes). Note that 32-bit ARM does not populate its struct screen_info early enough for earlycon=efifb to work, so it is disabled there. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Alexander Graf <agraf@suse.de> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Bjorn Andersson <bjorn.andersson@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Heinrich Schuchardt <xypron.glpk@gmx.de> Cc: Jeffrey Hugo <jhugo@codeaurora.org> Cc: Lee Jones <lee.jones@linaro.org> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20190202094119.13230-10-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-12efi/libstub/arm: default EFI_ARMSTUB_DTB_LOADER to yScott Branden
Default EFI_ARMSTUB_DTB_LOADER to y to allow the dtb= command line parameter to function with efi loader. Required for development purposes and to boot on existing bootloaders that do not support devicetree provided by the firmware or by the bootloader. Fixes: 3d7ee348aa41 ("efi/libstub/arm: Add opt-in Kconfig option ...") Signed-off-by: Scott Branden <scott.branden@broadcom.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2018-07-16efi/libstub/arm: Add opt-in Kconfig option for the DTB loaderArd Biesheuvel
There are various ways a platform can provide a device tree binary to the kernel, with different levels of sophistication: - ideally, the UEFI firmware, which is tightly coupled with the platform, provides a device tree image directly as a UEFI configuration table, and typically permits the contents to be manipulated either via menu options or via UEFI environment variables that specify a replacement image, - GRUB for ARM has a 'devicetree' directive which allows a device tree image to be loaded from any location accessible to GRUB, and supersede the one provided by the firmware, - the EFI stub implements a dtb= command line option that allows a device tree image to be loaded from a file residing in the same file system as the one the kernel image was loaded from. The dtb= command line option was never intended to be more than a development feature, to allow the other options to be implemented in parallel. So let's make it an opt-in feature that is disabled by default, but can be re-enabled at will. Note that we already disable the dtb= command line option when we detect that we are running with UEFI Secure Boot enabled. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Alexander Graf <agraf@suse.de> Acked-by: Leif Lindholm <leif.lindholm@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20180711094040.12506-7-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-14efi: Decode IA32/X64 Processor Error SectionYazen Ghannam
Recognize the IA32/X64 Processor Error Section. Do the section decoding in a new "cper-x86.c" file and add this to the Makefile depending on a new "UEFI_CPER_X86" config option. Print the Local APIC ID and CPUID info from the Processor Error Record. The "Processor Error Info" and "Processor Context" fields will be decoded in following patches. Based on UEFI 2.7 Table 252. Processor Error Record. Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20180504060003.19618-5-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-01Merge tag 'kconfig-v4.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kconfig updates from Masahiro Yamada: "A pretty big batch of Kconfig updates. I have to mention the lexer and parser of Kconfig are now built from real .l and .y sources. So, flex and bison are the requirement for building the kernel. Both of them (unlike gperf) have been stable for a long time. This change has been tested several weeks in linux-next, and I did not receive any problem report about this. Summary: - add checks for mistakes, like the choice default is not in choice, help is doubled - document data structure and complex code - fix various memory leaks - change Makefile to build lexer and parser instead of using pre-generated C files - drop 'boolean' keyword, which is equivalent to 'bool' - use default 'yy' prefix and remove unneeded Make variables - fix gettext() check for xconfig - announce that oldnoconfig will be finally removed - make 'Selected by:' and 'Implied by' readable in help and search result - hide silentoldconfig from 'make help' to stop confusing people - fix misc things and cleanups" * tag 'kconfig-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (37 commits) kconfig: Remove silentoldconfig from help and docs; fix kconfig/conf's help kconfig: make "Selected by:" and "Implied by:" readable kconfig: announce removal of oldnoconfig if used kconfig: fix make xconfig when gettext is missing kconfig: Clarify menu and 'if' dependency propagation kconfig: Document 'if' flattening logic kconfig: Clarify choice dependency propagation kconfig: Document SYMBOL_OPTIONAL logic kbuild: remove unnecessary LEX_PREFIX and YACC_PREFIX kconfig: use default 'yy' prefix for lexer and parser kconfig: make conf_unsaved a local variable of conf_read() kconfig: make xfgets() really static kconfig: make input_mode static kconfig: Warn if there is more than one help text kconfig: drop 'boolean' keyword kconfig: use bool instead of boolean for type definition attributes, again kconfig: Remove menu_end_entry() kconfig: Document important expression functions kconfig: Document automatic submenu creation code kconfig: Fix choice symbol expression leak ...
2018-01-22kconfig: use bool instead of boolean for type definition attributes, againMasahiro Yamada
Commit 6341e62b212a ("kconfig: use bool instead of boolean for type definition attributes") did treewide replacement of 'boolean', and also mentioned the keyword 'boolean' would be dropped later on. Some years have passed, but it has not happened yet. Meanwhile, some new instances have come up. I am really going to drop this keyword. I need to do the replacement once again. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-19x86/efi: Clarify that reset attack mitigation needs appropriate userspaceMatthew Garrett
Some distributions have turned on the reset attack mitigation feature, which is designed to force the platform to clear the contents of RAM if the machine is shut down uncleanly. However, in order for the platform to be able to determine whether the shutdown was clean or not, userspace has to be configured to clear the MemoryOverwriteRequest flag on shutdown - otherwise the firmware will end up clearing RAM on every reboot, which is unnecessarily time consuming. Add some additional clarity to the kconfig text to reduce the risk of systems being configured this way. Signed-off-by: Matthew Garrett <mjg59@google.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-03efi: Move ARM CPER code to new fileTyler Baicar
The ARM CPER code is currently mixed in with the other CPER code. Move it to a new file to separate it from the rest of the CPER code. Signed-off-by: Tyler Baicar <tbaicar@codeaurora.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Arvind Yadav <arvind.yadav.cs@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasyl Gomonovych <gomonovych@gmail.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20180102181042.19074-5-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>