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2014-12-09Merge tag 'arm64-upstream' of ↵Linus Torvalds
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 Rutland
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 Biesheuvel
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 Zyngier
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 Salter
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>