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2020-04-03Merge tag 'spdx-5.7-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx Pull SPDX updates from Greg KH: "Here are three SPDX patches for 5.7-rc1. One fixes up the SPDX tag for a single driver, while the other two go through the tree and add SPDX tags for all of the .gitignore files as needed. Nothing too complex, but you will get a merge conflict with your current tree, that should be trivial to handle (one file modified by two things, one file deleted.) All three of these have been in linux-next for a while, with no reported issues other than the merge conflict" * tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx: ASoC: MT6660: make spdxcheck.py happy .gitignore: add SPDX License Identifier .gitignore: remove too obvious comments
2020-04-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree updates from Jiri Kosina: "My attempt to revitalize trivial queue I've been neglecting for years (what a disaster that was for this world, right? :) ) with patches collected from backlog that were still relevant and not applied elsewhere in the meantime" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: err.h: remove deprecated PTR_RET for good blk-mq: Fix typo in comment x86/boot: Fix comment spelling sh: mach-highlander: Fix comment spelling s390/dasd: Fix comment spelling mfd: wm8994: Fix comment spelling docs: Add reference in binfmt-misc.rst genirq: fix kerneldoc comment for irq_desc drm/amdgpu: fix two documentation mismatch issues HID: fix Kconfig word ordering list/hashtable: minor documentation corrections.
2020-03-31Merge branch 'x86-boot-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 boot updates from Ingo Molnar: "Misc cleanups and small enhancements all around the map" * 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot/compressed: Fix debug_puthex() parameter type x86/setup: Fix static memory detection x86/vmlinux: Drop unneeded linker script discard of .eh_frame x86/*/Makefile: Use -fno-asynchronous-unwind-tables to suppress .eh_frame sections x86/boot/compressed: Remove .eh_frame section from bzImage x86/boot/compressed/64: Remove .bss/.pgtable from bzImage x86/boot/compressed/64: Use 32-bit (zero-extended) MOV for z_output_len x86/boot/compressed/64: Use LEA to initialize boot stack pointer
2020-03-28x86/boot/compressed: Fix debug_puthex() parameter typeJoerg Roedel
In the CONFIG_X86_VERBOSE_BOOTUP=Y case, the debug_puthex() macro just turns into __puthex(), which takes 'unsigned long' as parameter. But in the CONFIG_X86_VERBOSE_BOOTUP=N case, it is a function which takes 'unsigned char *', causing compile warnings when the function is used. Fix the parameter type to get rid of the warnings. Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20200319091407.1481-11-joro@8bytes.org
2020-03-25.gitignore: add SPDX License IdentifierMasahiro Yamada
Add SPDX License Identifier to all .gitignore files. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17x86/boot: Fix comment spellingGeert Uytterhoeven
Fix misspelling of "disconnect". Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2020-03-08efi/x86: Don't relocate the kernel unless necessaryArvind Sankar
Add alignment slack to the PE image size, so that we can realign the decompression buffer within the space allocated for the image. Only relocate the kernel if it has been loaded at an unsuitable address: - Below LOAD_PHYSICAL_ADDR, or - Above 64T for 64-bit and 512MiB for 32-bit For 32-bit, the upper limit is conservative, but the exact limit can be difficult to calculate. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200303221205.4048668-6-nivedita@alum.mit.edu Link: https://lore.kernel.org/r/20200308080859.21568-20-ardb@kernel.org
2020-03-08efi/x86: Remove extra headroom for setup blockArvind Sankar
The following commit: 223e3ee56f77 ("efi/x86: add headroom to decompressor BSS to account for setup block") added headroom to the PE image to account for the setup block, which wasn't used for the decompression buffer. Now that the decompression buffer is located at the start of the image, and includes the setup block, this is no longer required. Add a check to make sure that the head section of the compressed kernel won't overwrite itself while relocating. This is only for future-proofing as with current limits on the setup and the actual size of the head section, this can never happen. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200303221205.4048668-5-nivedita@alum.mit.edu Link: https://lore.kernel.org/r/20200308080859.21568-19-ardb@kernel.org
2020-03-08efi/x86: Add kernel preferred address to PE headerArvind Sankar
Store the kernel's link address as ImageBase in the PE header. Note that the PE specification requires the ImageBase to be 64k aligned. The preferred address should almost always satisfy that, except for 32-bit kernel if the configuration has been customized. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200303221205.4048668-4-nivedita@alum.mit.edu Link: https://lore.kernel.org/r/20200308080859.21568-18-ardb@kernel.org
2020-03-08efi/x86: Decompress at start of PE image load addressArvind Sankar
When booted via PE loader, define image_offset to hold the offset of startup_32() from the start of the PE image, and use it as the start of the decompression buffer. [ mingo: Fixed the grammar in the comments. ] Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200303221205.4048668-3-nivedita@alum.mit.edu Link: https://lore.kernel.org/r/20200308080859.21568-17-ardb@kernel.org
2020-03-08x86/boot/compressed/32: Save the output address instead of recalculating itArvind Sankar
In preparation for being able to decompress into a buffer starting at a different address than startup_32, save the calculated output address instead of recalculating it later. We now keep track of three addresses: %edx: startup_32 as we were loaded by bootloader %ebx: new location of compressed kernel %ebp: start of decompression buffer Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200303221205.4048668-2-nivedita@alum.mit.edu Link: https://lore.kernel.org/r/20200308080859.21568-16-ardb@kernel.org
2020-03-08x86/boot: Use unsigned comparison for addressesArvind Sankar
The load address is compared with LOAD_PHYSICAL_ADDR using a signed comparison currently (using jge instruction). When loading a 64-bit kernel using the new efi32_pe_entry() point added by: 97aa276579b2 ("efi/x86: Add true mixed mode entry point into .compat section") using Qemu with -m 3072, the firmware actually loads us above 2Gb, resulting in a very early crash. Use the JAE instruction to perform a unsigned comparison instead, as physical addresses should be considered unsigned. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200301230436.2246909-6-nivedita@alum.mit.edu Link: https://lore.kernel.org/r/20200308080859.21568-14-ardb@kernel.org
2020-03-08efi/x86: Avoid using code32_startArvind Sankar
code32_start is meant for 16-bit real-mode bootloaders to inform the kernel where the 32-bit protected mode code starts. Nothing in the protected mode kernel except the EFI stub uses it. efi_main() currently returns boot_params, with code32_start set inside it to tell efi_stub_entry() where startup_32 is located. Since it was invoked by efi_stub_entry() in the first place, boot_params is already known. Return the address of startup_32 instead. This will allow a 64-bit kernel to live above 4Gb, for example, and it's cleaner as well. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200301230436.2246909-5-nivedita@alum.mit.edu Link: https://lore.kernel.org/r/20200308080859.21568-13-ardb@kernel.org
2020-03-08efi/x86: Make efi32_pe_entry() more readableArvind Sankar
Set up a proper frame pointer in efi32_pe_entry() so that it's easier to calculate offsets for arguments. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200301230436.2246909-4-nivedita@alum.mit.edu Link: https://lore.kernel.org/r/20200308080859.21568-12-ardb@kernel.org
2020-03-08efi/x86: Respect 32-bit ABI in efi32_pe_entry()Arvind Sankar
verify_cpu() clobbers BX and DI. In case we have to return error, we need to preserve them to respect the 32-bit calling convention. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200301230436.2246909-3-nivedita@alum.mit.edu Link: https://lore.kernel.org/r/20200308080859.21568-11-ardb@kernel.org
2020-03-08efi/x86: Annotate the LOADED_IMAGE_PROTOCOL_GUID with SYM_DATAArvind Sankar
Use SYM_DATA*() macros to annotate this constant, and explicitly align it to 4-byte boundary. Use lower-case for hexadecimal data. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20200301230436.2246909-2-nivedita@alum.mit.edu Link: https://lore.kernel.org/r/20200308080859.21568-10-ardb@kernel.org
2020-02-29x86/boot/compressed: Fix reloading of GDTR post-relocationArvind Sankar
The following commit: ef5a7b5eb13e ("efi/x86: Remove GDT setup from efi_main") introduced GDT setup into the 32-bit kernel's startup_32, and reloads the GDTR after relocating the kernel for paranoia's sake. A followup commit: 32d009137a56 ("x86/boot: Reload GDTR after copying to the end of the buffer") introduced a similar GDTR reload in the 64-bit kernel as well. The GDTR is adjusted by (init_size-_end), however this may not be the correct offset to apply if the kernel was loaded at a misaligned address or below LOAD_PHYSICAL_ADDR, as in that case the decompression buffer has an additional offset from the original load address. This should never happen for a conformant bootloader, but we're being paranoid anyway, so just store the new GDT address in there instead of adding any offsets, which is simpler as well. Fixes: ef5a7b5eb13e ("efi/x86: Remove GDT setup from efi_main") Fixes: 32d009137a56 ("x86/boot: Reload GDTR after copying to the end of the buffer") Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: linux-efi@vger.kernel.org Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86@kernel.org Link: https://lore.kernel.org/r/20200226230031.3011645-2-nivedita@alum.mit.edu
2020-02-26Merge tag 'efi-next' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi into efi/core Pull EFI updates for v5.7 from Ard Biesheuvel: This time, the set of changes for the EFI subsystem is much larger than usual. The main reasons are: - Get things cleaned up before EFI support for RISC-V arrives, which will increase the size of the validation matrix, and therefore the threshold to making drastic changes, - After years of defunct maintainership, the GRUB project has finally started to consider changes from the distros regarding UEFI boot, some of which are highly specific to the way x86 does UEFI secure boot and measured boot, based on knowledge of both shim internals and the layout of bootparams and the x86 setup header. Having this maintenance burden on other architectures (which don't need shim in the first place) is hard to justify, so instead, we are introducing a generic Linux/UEFI boot protocol. Summary of changes: - Boot time GDT handling changes (Arvind) - Simplify handling of EFI properties table on arm64 - Generic EFI stub cleanups, to improve command line handling, file I/O, memory allocation, etc. - Introduce a generic initrd loading method based on calling back into the firmware, instead of relying on the x86 EFI handover protocol or device tree. - Introduce a mixed mode boot method that does not rely on the x86 EFI handover protocol either, and could potentially be adopted by other architectures (if another one ever surfaces where one execution mode is a superset of another) - Clean up the contents of struct efi, and move out everything that doesn't need to be stored there. - Incorporate support for UEFI spec v2.8A changes that permit firmware implementations to return EFI_UNSUPPORTED from UEFI runtime services at OS runtime, and expose a mask of which ones are supported or unsupported via a configuration table. - Various documentation updates and minor code cleanups (Heinrich) - Partial fix for the lack of by-VA cache maintenance in the decompressor on 32-bit ARM. Note that these patches were deliberately put at the beginning so they can be used as a stable branch that will be shared with a PR containing the complete fix, which I will send to the ARM tree. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-02-25x86/vmlinux: Drop unneeded linker script discard of .eh_frameArvind Sankar
Now that .eh_frame sections for the files in setup.elf and realmode.elf are not generated anymore, the linker scripts don't need the special output section name /DISCARD/ any more. Remove the one in the main kernel linker script as well, since there are no .eh_frame sections already, and fix up a comment referencing .eh_frame. Update the comment in asm/dwarf2.h referring to .eh_frame so it continues to make sense, as well as being more specific. [ bp: Touch up commit message. ] Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Tested-by: Nathan Chancellor <natechancellor@gmail.com> Link: https://lkml.kernel.org/r/20200224232129.597160-3-nivedita@alum.mit.edu
2020-02-25x86/*/Makefile: Use -fno-asynchronous-unwind-tables to suppress .eh_frame ↵Arvind Sankar
sections While discussing a patch to discard .eh_frame from the compressed vmlinux using the linker script, Fangrui Song pointed out [1] that these sections shouldn't exist in the first place because arch/x86/Makefile uses -fno-asynchronous-unwind-tables. It turns out this is because the Makefiles used to build the compressed kernel redefine KBUILD_CFLAGS, dropping this flag. Add the flag to the Makefile for the compressed kernel, as well as the EFI stub Makefile to fix this. Also add the flag to boot/Makefile and realmode/rm/Makefile so that the kernel's boot code (boot/setup.elf) and realmode trampoline (realmode/rm/realmode.elf) won't be compiled with .eh_frame sections, since their linker scripts also just discard them. [1] https://lore.kernel.org/lkml/20200222185806.ywnqhfqmy67akfsa@google.com/ Suggested-by: Fangrui Song <maskray@google.com> Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Tested-by: Nathan Chancellor <natechancellor@gmail.com> Link: https://lkml.kernel.org/r/20200224232129.597160-2-nivedita@alum.mit.edu
2020-02-24x86/boot/compressed: Remove .eh_frame section from bzImageArvind Sankar
Discarding unnecessary sections with "*(*)" (see thread at Link: below) works fine with the bfd linker but fails with lld: $ make -j$(nproc) -s CC=clang LD=ld.lld O=out.x86_64 distclean defconfig bzImage ld.lld: error: discarding .shstrtab section is not allowed lld tries to also discard essential sections like .shstrtab, .symtab and .strtab, which results in the link failing since .shstrtab is required by the ELF specification: the e_shstrndx field in the ELF header is the index of .shstrtab, and each section in the section table is required to have an sh_name that points into the .shstrtab. .symtab and .strtab are also necessary to generate the zoffset.h file for the bzImage header. Since the only sizeable section that can be discarded is .eh_frame, restrict the discard to only .eh_frame to be safe. [ bp: Flesh out commit message and replace offending commit with this one. ] Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Borislav Petkov <bp@suse.de> Tested-by: Nathan Chancellor <natechancellor@gmail.com> Link: https://lkml.kernel.org/r/20200109150218.16544-2-nivedita@alum.mit.edu
2020-02-23efi/libstub: Introduce symbolic constants for the stub major/minor versionArd Biesheuvel
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>
2020-02-23efi/x86: Use symbolic constants in PE header instead of bare numbersArd Biesheuvel
Replace bare numbers in the PE/COFF header structure with symbolic constants so they become self documenting. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23efi/x86: Add true mixed mode entry point into .compat sectionArd Biesheuvel
Currently, mixed mode is closely tied to the EFI handover protocol and relies on intimate knowledge of the bootparams structure, setup header etc, all of which are rather byzantine and entirely specific to x86. Even though no other EFI supported architectures are currently known that could support something like mixed mode, it still makes sense to abstract a bit from this, and make it part of a generic Linux on EFI boot protocol. To that end, add a .compat section to the mixed mode binary, and populate it with the PE machine type and entry point address, allowing firmware implementations to match it to their native machine type, and invoke non-native binaries using a secondary entry point. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23efi/x86: Implement mixed mode boot without the handover protocolArd Biesheuvel
Add support for booting 64-bit x86 kernels from 32-bit firmware running on 64-bit capable CPUs without requiring the bootloader to implement the EFI handover protocol or allocate the setup block, etc etc, all of which can be done by the stub itself, using code that already exists. Instead, create an ordinary EFI application entrypoint but implemented in 32-bit code [so that it can be invoked by 32-bit firmware], and stash the address of this 32-bit entrypoint in the .compat section where the bootloader can find it. Note that we use the setup block embedded in the binary to go through startup_32(), but it gets reallocated and copied in efi_pe_entry(), using the same code that runs when the x86 kernel is booted in EFI mode from native firmware. This requires the loaded image protocol to be installed on the kernel image's EFI handle, and point to the kernel image itself and not to its loader. This, in turn, requires the bootloader to use the LoadImage() boot service to load the 64-bit image from 32-bit firmware, which is in fact supported by firmware based on EDK2. (Only StartImage() will fail, and instead, the newly added entrypoint needs to be invoked) Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23efi/x86: Drop redundant .bss sectionArd Biesheuvel
In commit c7fb93ec51d462ec ("x86/efi: Include a .bss section within the PE/COFF headers") we added a separate .bss section to the PE/COFF header of the compressed kernel describing the static memory footprint of the decompressor, to ensure that it has enough headroom to decompress itself. We can achieve the exact same result by increasing the virtual size of the .text section, without changing the raw size, which, as per the PE/COFF specification, requires the loader to zero initialize the delta. Doing so frees up a slot in the section table, which we will use later to describe the mixed mode entrypoint. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23efi/x86: add headroom to decompressor BSS to account for setup blockArd Biesheuvel
In the bootparams struct, init_size defines the static footprint of the bzImage, counted from the start of the kernel image, i.e., startup_32(). The PE/COFF metadata declares the same size for the entire image, but this time, the image includes the setup block as well, and so the space reserved by UEFI is a bit too small. This usually doesn't matter, since we normally relocate the kernel into a memory allocation of the correct size. But in the unlikely case that the image happens to be loaded at exactly the preferred offset, we skip this relocation, and execute the image in place, stepping on memory beyond the provided allocation, which may be in use for other purposes. Let's fix this by adding the size of the setup block to the image size as declared in the PE/COFF header. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-23efi/libstub/x86: Incorporate eboot.c into libstubArd Biesheuvel
Most of the EFI stub source files of all architectures reside under drivers/firmware/efi/libstub, where they share a Makefile with special CFLAGS and an include file with declarations that are only relevant for stub code. Currently, we carry a lot of stub specific stuff in linux/efi.h only because eboot.c in arch/x86 needs them as well. So let's move eboot.c into libstub/, and move the contents of eboot.h that we still care about into efistub.h Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-22efi/libstub/x86: Avoid overflowing code32_start on PE entryArd Biesheuvel
When using the native PE entry point (as opposed to the EFI handover protocol entry point that is used more widely), we set code32_start, which is a 32-bit wide field, to the effective symbol address of startup_32, which could overflow given that the EFI loader may have located the running image anywhere in memory, and we haven't reached the point yet where we relocate ourselves. Since we relocate ourselves if code32_start != pref_address, this isn't likely to lead to problems in practice, given how unlikely it is that the truncated effective address of startup_32 happens to equal pref_address. But it is better to defer the assignment of code32_start to after the relocation, when it is guaranteed to fit. While at it, move the call to efi_relocate_kernel() to an earlier stage so it is more likely that our preferred offset in memory has not been occupied by other memory allocations done in the mean time. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-22efi/libstub/x86: Remove pointless zeroing of apm_bios_infoArd Biesheuvel
We have some code in the EFI stub entry point that takes the address of the apm_bios_info struct in the newly allocated and zeroed out boot_params structure, only to zero it out again. This is pointless so remove it. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-22efi/x86: Mark setup_graphics staticArvind Sankar
This function is only called from efi_main in the same source file. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Link: https://lore.kernel.org/r/20200130222004.1932152-1-nivedita@alum.mit.edu Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-22x86/boot: Micro-optimize GDT loading instructionsArvind Sankar
Rearrange the instructions a bit to use a 32-bit displacement once instead of 2/3 times. This saves 8 bytes of machine code. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Link: https://lore.kernel.org/r/20200202171353.3736319-8-nivedita@alum.mit.edu Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-22x86/boot: GDT limit value should be size - 1Arvind Sankar
The limit value for the GDTR should be such that adding it to the base address gives the address of the last byte of the GDT, i.e. it should be one less than the size, not the size. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Link: https://lore.kernel.org/r/20200202171353.3736319-7-nivedita@alum.mit.edu Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-22efi/x86: Remove GDT setup from efi_mainArvind Sankar
The 64-bit kernel will already load a GDT in startup_64, which is the next function to execute after return from efi_main. Add GDT setup code to the 32-bit kernel's startup_32 as well. Doing it in the head code has the advantage that we can avoid potentially corrupting the GDT during copy/decompression. This also removes dependence on having a specific GDT layout setup by the bootloader. Both startup_32 and startup_64 now clear interrupts on entry, so we can remove that from efi_main as well. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Link: https://lore.kernel.org/r/20200202171353.3736319-6-nivedita@alum.mit.edu Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-22x86/boot: Clear direction and interrupt flags in startup_64Arvind Sankar
startup_32 already clears these flags on entry, do it in startup_64 as well for consistency. The direction flag in particular is not specified to be cleared in the boot protocol documentation, and we currently call into C code (paging_prepare) without explicitly clearing it. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Link: https://lore.kernel.org/r/20200202171353.3736319-5-nivedita@alum.mit.edu Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-22x86/boot: Reload GDTR after copying to the end of the bufferArvind Sankar
The GDT may get overwritten during the copy or during extract_kernel, which will cause problems if any segment register is touched before the GDTR is reloaded by the decompressed kernel. For safety update the GDTR to point to the GDT within the copied kernel. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Link: https://lore.kernel.org/r/20200202171353.3736319-4-nivedita@alum.mit.edu Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-22efi/x86: Don't depend on firmware GDT layoutArvind Sankar
When booting in mixed mode, the firmware's GDT is still installed at handover entry in efi32_stub_entry. We save the GDTR for later use in __efi64_thunk but we are assuming that descriptor 2 (__KERNEL_CS) is a valid 32-bit code segment descriptor and that descriptor 3 (__KERNEL_DS/__BOOT_DS) is a valid data segment descriptor. This happens to be true for OVMF (it actually uses descriptor 1 for data segments, but descriptor 3 is also setup as data), but we shouldn't depend on this being the case. Fix this by saving the code and data selectors in addition to the GDTR in efi32_stub_entry, and restoring them in __efi64_thunk before calling the firmware. The UEFI specification guarantees that selectors will be flat, so using the DS selector for all the segment registers should be enough. We also need to install our own GDT before initializing segment registers in startup_32, so move the GDT load up to the beginning of the function. [ardb: mention mixed mode in the commit log] Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Link: https://lore.kernel.org/r/20200202171353.3736319-3-nivedita@alum.mit.edu Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-22x86/boot: Remove KEEP_SEGMENTS supportArvind Sankar
Commit a24e785111a3 ("i386: paravirt boot sequence") added this flag for use by paravirtualized environments such as Xen. However, Xen never made use of this flag [1], and it was only ever used by lguest [2]. Commit ecda85e70277 ("x86/lguest: Remove lguest support") removed lguest, so KEEP_SEGMENTS has lost its last user. [1] https://lore.kernel.org/lkml/4D4B097C.5050405@goop.org [2] https://www.mail-archive.com/lguest@lists.ozlabs.org/msg00469.html Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Link: https://lore.kernel.org/r/20200202171353.3736319-2-nivedita@alum.mit.edu Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2020-02-19x86/boot/compressed/64: Remove .bss/.pgtable from bzImageArvind Sankar
Commit 5b11f1cee579 ("x86, boot: straighten out ranges to copy/zero in compressed/head*.S") introduced a separate .pgtable section, splitting it out from the rest of .bss. This section was added without the writeable flag, marking it as read-only. This results in the linker putting the .rela.dyn section (containing bogus dynamic relocations from head_64.o) after the .bss and .pgtable sections. When objcopy is used to convert compressed/vmlinux into a binary for the bzImage: $ objcopy -O binary -R .note -R .comment -S arch/x86/boot/compressed/vmlinux \ arch/x86/boot/vmlinux.bin the .bss and .pgtable sections get materialized as ~176KiB of zero bytes in the binary in order to place .rela.dyn at the correct location. Fix this by marking .pgtable as writeable. This moves the .rela.dyn section up in the ELF image layout so that .bss and .pgtable are the last allocated sections and so don't appear in bzImage. [ bp: Massage commit message. ] Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Kees Cook <keescook@chromium.org> Link: https://lkml.kernel.org/r/20200109150218.16544-1-nivedita@alum.mit.edu
2020-02-19x86/boot/compressed: Don't declare __force_order in kaslr_64.cH.J. Lu
GCC 10 changed the default to -fno-common, which leads to LD arch/x86/boot/compressed/vmlinux ld: arch/x86/boot/compressed/pgtable_64.o:(.bss+0x0): multiple definition of `__force_order'; \ arch/x86/boot/compressed/kaslr_64.o:(.bss+0x0): first defined here make[2]: *** [arch/x86/boot/compressed/Makefile:119: arch/x86/boot/compressed/vmlinux] Error 1 Since __force_order is already provided in pgtable_64.c, there is no need to declare __force_order in kaslr_64.c. Signed-off-by: H.J. Lu <hjl.tools@gmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20200124181811.4780-1-hjl.tools@gmail.com
2020-02-12x86/boot/compressed/64: Use 32-bit (zero-extended) MOV for z_output_lenArvind Sankar
z_output_len is the size of the decompressed payload (i.e. vmlinux + vmlinux.relocs) and is generated as an unsigned 32-bit quantity by mkpiggy.c. The current movq $z_output_len, %r9 instruction generates a sign-extended move to %r9. Using movl $z_output_len, %r9d will instead zero-extend into %r9, which is appropriate for an unsigned 32-bit quantity. This is also what is already done for z_input_len, the size of the compressed payload. [ bp: Also, z_output_len cannot be a 64-bit quantity because it participates in: init_size: .long INIT_SIZE # kernel initialization size through INIT_SIZE which is a 32-bit quantity determined by the .long directive (vs .quad for 64-bit). Furthermore, if it really must be a 64-bit quantity, then the insn must be MOVABS which can accommodate a 64-bit immediate and which the toolchain does not generate automatically. ] Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20200211173333.1722739-1-nivedita@alum.mit.edu
2020-02-12x86/boot/compressed/64: Use LEA to initialize boot stack pointerArvind Sankar
It's shorter, and it's what is used in every other place, so make it consistent. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20200107194436.2166846-2-nivedita@alum.mit.edu
2020-02-09Merge tag 'kbuild-v5.6-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull more Kbuild updates from Masahiro Yamada: - fix randconfig to generate a sane .config - rename hostprogs-y / always to hostprogs / always-y, which are more natual syntax. - optimize scripts/kallsyms - fix yes2modconfig and mod2yesconfig - make multiple directory targets ('make foo/ bar/') work * tag 'kbuild-v5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kbuild: make multiple directory targets work kconfig: Invalidate all symbols after changing to y or m. kallsyms: fix type of kallsyms_token_table[] scripts/kallsyms: change table to store (strcut sym_entry *) scripts/kallsyms: rename local variables in read_symbol() kbuild: rename hostprogs-y/always to hostprogs/always-y kbuild: fix the document to use extra-y for vmlinux.lds kconfig: fix broken dependency in randconfig-generated .config
2020-02-09Merge tag 'x86-urgent-2020-02-09' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "A set of fixes for X86: - Ensure that the PIT is set up when the local APIC is disable or configured in legacy mode. This is caused by an ordering issue introduced in the recent changes which skip PIT initialization when the TSC and APIC frequencies are already known. - Handle malformed SRAT tables during early ACPI parsing which caused an infinite loop anda boot hang. - Fix a long standing race in the affinity setting code which affects PCI devices with non-maskable MSI interrupts. The problem is caused by the non-atomic writes of the MSI address (destination APIC id) and data (vector) fields which the device uses to construct the MSI message. The non-atomic writes are mandated by PCI. If both fields change and the device raises an interrupt after writing address and before writing data, then the MSI block constructs a inconsistent message which causes interrupts to be lost and subsequent malfunction of the device. The fix is to redirect the interrupt to the new vector on the current CPU first and then switch it over to the new target CPU. This allows to observe an eventually raised interrupt in the transitional stage (old CPU, new vector) to be observed in the APIC IRR and retriggered on the new target CPU and the new vector. The potential spurious interrupts caused by this are harmless and can in the worst case expose a buggy driver (all handlers have to be able to deal with spurious interrupts as they can and do happen for various reasons). - Add the missing suspend/resume mechanism for the HYPERV hypercall page which prevents resume hibernation on HYPERV guests. This change got lost before the merge window. - Mask the IOAPIC before disabling the local APIC to prevent potentially stale IOAPIC remote IRR bits which cause stale interrupt lines after resume" * tag 'x86-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic: Mask IOAPIC entries when disabling the local APIC x86/hyperv: Suspend/resume the hypercall page for hibernation x86/apic/msi: Plug non-maskable MSI affinity race x86/boot: Handle malformed SRAT tables during early ACPI parsing x86/timer: Don't skip PIT setup when APIC is disabled or in legacy mode
2020-02-04kbuild: rename hostprogs-y/always to hostprogs/always-yMasahiro Yamada
In old days, the "host-progs" syntax was used for specifying host programs. It was renamed to the current "hostprogs-y" in 2004. It is typically useful in scripts/Makefile because it allows Kbuild to selectively compile host programs based on the kernel configuration. This commit renames like follows: always -> always-y hostprogs-y -> hostprogs So, scripts/Makefile will look like this: always-$(CONFIG_BUILD_BIN2C) += ... always-$(CONFIG_KALLSYMS) += ... ... hostprogs := $(always-y) $(always-m) I think this makes more sense because a host program is always a host program, irrespective of the kernel configuration. We want to specify which ones to compile by CONFIG options, so always-y will be handier. The "always", "hostprogs-y", "hostprogs-m" will be kept for backward compatibility for a while. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-01-31x86/boot: Handle malformed SRAT tables during early ACPI parsingSteven Clarkson
Break an infinite loop when early parsing of the SRAT table is caused by a subtable with zero length. Known to affect the ASUS WS X299 SAGE motherboard with firmware version 1201 which has a large block of zeros in its SRAT table. The kernel could boot successfully on this board/firmware prior to the introduction of early parsing this table or after a BIOS update. [ bp: Fixup whitespace damage and commit message. Make it return 0 to denote that there are no immovable regions because who knows what else is broken in this BIOS. ] Fixes: 02a3e3cdb7f1 ("x86/boot: Parse SRAT table and count immovable memory regions") Signed-off-by: Steven Clarkson <sc@lambdal.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: linux-acpi@vger.kernel.org Link: https://bugzilla.kernel.org/show_bug.cgi?id=206343 Link: https://lkml.kernel.org/r/CAHKq8taGzj0u1E_i=poHUam60Bko5BpiJ9jn0fAupFUYexvdUQ@mail.gmail.com
2020-01-28Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpu-features updates from Ingo Molnar: "The biggest change in this cycle was a large series from Sean Christopherson to clean up the handling of VMX features. This both fixes bugs/inconsistencies and makes the code more coherent and future-proof. There are also two cleanups and a minor TSX syslog messages enhancement" * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) x86/cpu: Remove redundant cpu_detect_cache_sizes() call x86/cpu: Print "VMX disabled" error message iff KVM is enabled KVM: VMX: Allow KVM_INTEL when building for Centaur and/or Zhaoxin CPUs perf/x86: Provide stubs of KVM helpers for non-Intel CPUs KVM: VMX: Use VMX_FEATURE_* flags to define VMCS control bits KVM: VMX: Check for full VMX support when verifying CPU compatibility KVM: VMX: Use VMX feature flag to query BIOS enabling KVM: VMX: Drop initialization of IA32_FEAT_CTL MSR x86/cpufeatures: Add flag to track whether MSR IA32_FEAT_CTL is configured x86/cpu: Set synthetic VMX cpufeatures during init_ia32_feat_ctl() x86/cpu: Print VMX flags in /proc/cpuinfo using VMX_FEATURES_* x86/cpu: Detect VMX features on Intel, Centaur and Zhaoxin CPUs x86/vmx: Introduce VMX_FEATURES_* x86/cpu: Clear VMX feature flag if VMX is not fully enabled x86/zhaoxin: Use common IA32_FEAT_CTL MSR initialization x86/centaur: Use common IA32_FEAT_CTL MSR initialization x86/mce: WARN once if IA32_FEAT_CTL MSR is left unlocked x86/intel: Initialize IA32_FEAT_CTL MSR at boot tools/x86: Sync msr-index.h from kernel sources selftests, kvm: Replace manual MSR defs with common msr-index.h ...
2020-01-28Merge branch 'x86-boot-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 boot update from Ingo Molnar: "Two minor changes: fix an atypical binutils combination build bug, and also fix a VRAM size check for simplefb" * 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/sysfb: Fix check for bad VRAM size x86/boot: Discard .eh_frame sections
2020-01-28Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 asm updates from Ingo Molnar: "Misc updates: - Remove last remaining calls to exception_enter/exception_exit() and simplify the entry code some more. - Remove force_iret() - Add support for "Fast Short Rep Mov", which is available starting with Ice Lake Intel CPUs - and make the x86 assembly version of memmove() use REP MOV for all sizes when FSRM is available. - Micro-optimize/simplify the 32-bit boot code a bit. - Use a more future-proof SYSRET instruction mnemonic" * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot: Simplify calculation of output address x86/entry/64: Add instruction suffix to SYSRET x86: Remove force_iret() x86/cpufeatures: Add support for fast short REP; MOVSB x86/context-tracking: Remove exception_enter/exit() from KVM_PV_REASON_PAGE_NOT_PRESENT async page fault x86/context-tracking: Remove exception_enter/exit() from do_page_fault()
2020-01-25efi/libstub/x86: Fix EFI server boot failureQian Cai
x86_64 EFI systems are unable to boot due to a typo in a recent commit: EFI config tables not found. -- System halted This was probably due to the absense of CONFIG_EFI_MIXED=y in testing. Fixes: 796eb8d26a57 ("efi/libstub/x86: Use const attribute for efi_is_64bit()") Signed-off-by: Qian Cai <cai@lca.pw> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: tglx@linutronix.de Cc: linux-efi@vger.kernel.org Link: https://lore.kernel.org/r/20200122191430.4888-1-cai@lca.pw
generated by cgit (git 2.34.1) at 2024-05-23 21:49:42 +0000