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2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner1-5/+1
Based on 2 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 version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-12arm64: Add software workaround for Falkor erratum 1041Shanker Donthineni1-0/+2
The ARM architecture defines the memory locations that are permitted to be accessed as the result of a speculative instruction fetch from an exception level for which all stages of translation are disabled. Specifically, the core is permitted to speculatively fetch from the 4KB region containing the current program counter 4K and next 4K. When translation is changed from enabled to disabled for the running exception level (SCTLR_ELn[M] changed from a value of 1 to 0), the Falkor core may errantly speculatively access memory locations outside of the 4KB region permitted by the architecture. The errant memory access may lead to one of the following unexpected behaviors. 1) A System Error Interrupt (SEI) being raised by the Falkor core due to the errant memory access attempting to access a region of memory that is protected by a slave-side memory protection unit. 2) Unpredictable device behavior due to a speculative read from device memory. This behavior may only occur if the instruction cache is disabled prior to or coincident with translation being changed from enabled to disabled. The conditions leading to this erratum will not occur when either of the following occur: 1) A higher exception level disables translation of a lower exception level (e.g. EL2 changing SCTLR_EL1[M] from a value of 1 to 0). 2) An exception level disabling its stage-1 translation if its stage-2 translation is enabled (e.g. EL1 changing SCTLR_EL1[M] from a value of 1 to 0 when HCR_EL2[VM] has a value of 1). To avoid the errant behavior, software must execute an ISB immediately prior to executing the MSR that will change SCTLR_ELn[M] from 1 to 0. Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-01-17arm64: efi-entry.S: avoid open-coded adr_lMark Rutland1-6/+3
Some places in the kernel open-code sequences using ADRP for a symbol another instruction using a :lo12: relocation for that same symbol. These sequences are easy to get wrong, and more painful to read than is necessary. For these reasons, it is preferable to use the {adr,ldr,str}_l macros for these cases. This patch makes use of these in efi-entry.S, removing open-coded sequences using adrp. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-14arm64: move early boot code to the .init segmentArd Biesheuvel1-1/+1
Apart from the arm64/linux and EFI header data structures, there is nothing in the .head.text section that must reside at the beginning of the Image. So let's move it to the .init section where it belongs. Note that this involves some minor tweaking of the EFI header, primarily because the address of 'stext' no longer coincides with the start of the .text section. It also requires a couple of relocated symbol references to be slightly rewritten or their definition moved to the linker script. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-03-04arm64: efi: add missing frame pointer assignmentArd Biesheuvel1-0/+1
The prologue of the EFI entry point pushes x29 and x30 onto the stack but fails to create the stack frame correctly by omitting the assignment of x29 to the new value of the stack pointer. So fix that. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-24arm64: avoid dynamic relocations in early boot codeArd Biesheuvel1-1/+1
Before implementing KASLR for arm64 by building a self-relocating PIE executable, we have to ensure that values we use before the relocation routine is executed are not subject to dynamic relocation themselves. This applies not only to virtual addresses, but also to values that are supplied by the linker at build time and relocated using R_AARCH64_ABS64 relocations. So instead, use assemble time constants, or force the use of static relocations by folding the constants into the instructions. Reviewed-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>
2015-10-12arm64/efi: isolate EFI stub from the kernel properArd Biesheuvel1-5/+5
Since arm64 does not use a builtin decompressor, the EFI stub is built into the kernel proper. So far, this has been working fine, but actually, since the stub is in fact a PE/COFF relocatable binary that is executed at an unknown offset in the 1:1 mapping provided by the UEFI firmware, we should not be seamlessly sharing code with the kernel proper, which is a position dependent executable linked at a high virtual offset. So instead, separate the contents of libstub and its dependencies, by putting them into their own namespace by prefixing all of its symbols with __efistub. This way, we have tight control over what parts of the kernel proper are referenced by the stub. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-12-09Merge tag 'arm64-upstream' of ↵Linus Torvalds1-1/+2
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "Here's the usual mixed bag of arm64 updates, also including some related EFI changes (Acked by Matt) and the MMU gather range cleanup (Acked by you). Changes include: - support for alternative instruction patching from Andre - seccomp from Akashi - some AArch32 instruction emulation, required by the Android folks - optimisations for exception entry/exit code, cmpxchg, pcpu atomics - mmu_gather range calculations moved into core code - EFI updates from Ard, including long-awaited SMBIOS support - /proc/cpuinfo fixes to align with the format used by arch/arm/ - a few non-critical fixes across the architecture" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (70 commits) arm64: remove the unnecessary arm64_swiotlb_init() arm64: add module support for alternatives fixups arm64: perf: Prevent wraparound during overflow arm64/include/asm: Fixed a warning about 'struct pt_regs' arm64: Provide a namespace to NCAPS arm64: bpf: lift restriction on last instruction arm64: Implement support for read-mostly sections arm64: compat: align cacheflush syscall with arch/arm arm64: add seccomp support arm64: add SIGSYS siginfo for compat task arm64: add seccomp syscall for compat task asm-generic: add generic seccomp.h for secure computing mode 1 arm64: ptrace: allow tracer to skip a system call arm64: ptrace: add NT_ARM_SYSTEM_CALL regset arm64: Move some head.text functions to executable section arm64: jump labels: NOP out NOP -> NOP replacement arm64: add support to dump the kernel page tables arm64: Add FIX_HOLE to permanent fixed addresses arm64: alternatives: fix pr_fmt string for consistency arm64: vmlinux.lds.S: don't discard .exit.* sections at link-time ...
2014-11-13arm64: efi: Fix stub cache maintenanceMark Rutland1-6/+21
While efi-entry.S mentions that efi_entry() will have relocated the kernel image, it actually means that efi_entry will have placed a copy of the kernel in the appropriate location, and until this is branched to at the end of efi_entry.S, all instructions are executed from the original image. Thus while the flush in efi_entry.S does ensure that the copy is visible to noncacheable accesses, it does not guarantee that this is true for the image instructions are being executed from. This could have disasterous effects when the MMU and caches are disabled if the image has not been naturally evicted to the PoC. Additionally, due to a missing dsb following the ic ialluis, the new kernel image is not necessarily clean in the I-cache when it is branched to, with similar potentially disasterous effects. This patch adds additional flushing to ensure that the currently executing stub text is flushed to the PoC and is thus visible to noncacheable accesses. As it is placed after the instructions cache maintenance for the new image and __flush_dcache_area already contains a dsb, we do not need to add a separate barrier to ensure completion of the icache maintenance. Comments are updated to clarify the situation with regard to the two images and the maintenance required for both. Fixes: 3c7f255039a2ad6ee1e3890505caf0d029b22e29 Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Joel Schopp <joel.schopp@amd.com> Reviewed-by: Roy Franz <roy.franz@linaro.org> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Ian Campbell <ijc@hellion.org.uk> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Mark Salter <msalter@redhat.com> Cc: Will Deacon <will.deacon@arm.com> Cc: stable@vger.kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-11-05arm64/efi: efistub: jump to 'stext' directly, not through the headerArd Biesheuvel1-1/+2
After the EFI stub has done its business, it jumps into the kernel by branching to offset #0 of the loaded Image, which is where it expects to find the header containing a 'branch to stext' instruction. However, the UEFI spec 2.1.1 states the following regarding PE/COFF image loading: "A UEFI image is loaded into memory through the LoadImage() Boot Service. This service loads an image with a PE32+ format into memory. This PE32+ loader is required to load all sections of the PE32+ image into memory." In other words, it is /not/ required to load parts of the image that are not covered by a PE/COFF section, so it may not have loaded the header at the expected offset, as it is not covered by any PE/COFF section. So instead, jump to 'stext' directly, which is at the base of the PE/COFF .text section, by supplying a symbol 'stext_offset' to efi-entry.o which contains the relative offset of stext into the Image. Also replace other open coded calculations of the same value with a reference to 'stext_offset' Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Roy Franz <roy.franz@linaro.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2014-07-04arm64: fix el2_setup check of CurrentELMarc Zyngier1-2/+1
The CurrentEL system register reports the Current Exception Level of the CPU. It doesn't say anything about the stack handling, and yet we compare it to PSR_MODE_EL2t and PSR_MODE_EL2h. It works by chance because PSR_MODE_EL2t happens to match the right bits, but that's otherwise a very bad idea. Just check for the EL value instead. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> [catalin.marinas@arm.com: fixed arch/arm64/kernel/efi-entry.S] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-04-30arm64: efi: add EFI stubMark Salter1-0/+109
This patch adds PE/COFF header fields to the start of the kernel Image so that it appears as an EFI application to UEFI firmware. An EFI stub is included to allow direct booting of the kernel Image. Signed-off-by: Mark Salter <msalter@redhat.com> [Add support in PE/COFF header for signed images] Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>