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* arm64: kexec: remove cpu-reset.hPasha Tatashin2021-10-011-4/+3
| | | | | | | | | | | | This header contains only cpu_soft_restart() which is never used directly anymore. So, remove this header, and rename the helper to be cpu_soft_restart(). Suggested-by: James Morse <james.morse@arm.com> Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20210930143113.1502553-15-pasha.tatashin@soleen.com Signed-off-by: Will Deacon <will@kernel.org>
* arm64: Use INIT_SCTLR_EL1_MMU_OFF to disable the MMU on CPU restartMarc Zyngier2021-03-181-4/+1
| | | | | | | | | Instead of doing a RMW on SCTLR_EL1 to disable the MMU, use the existing define that loads the right set of bits. Acked-by: Will Deacon <will@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org>
* arm64/relocate_kernel: remove redundant codePingfan Liu2020-09-111-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Kernel startup entry point requires disabling MMU and D-cache. As for kexec-reboot, taking a close look at "msr sctlr_el1, x12" in __cpu_soft_restart as the following: -1. booted at EL1 The instruction is enough to disable MMU and I/D cache for EL1 regime. -2. booted at EL2, using VHE Access to SCTLR_EL1 is redirected to SCTLR_EL2 in EL2. So the instruction is enough to disable MMU and clear I+C bits for EL2 regime. -3. booted at EL2, not using VHE The instruction itself can not affect EL2 regime. But The hyp-stub doesn't enable the MMU and I/D cache for EL2 regime. And KVM also disable them for EL2 regime when its unloaded, or execute a HVC_SOFT_RESTART call. So when kexec-reboot, the code in KVM has prepare the requirement. As a conclusion, disabling MMU and clearing I+C bits in SYM_CODE_START(arm64_relocate_new_kernel) is redundant, and can be removed Signed-off-by: Pingfan Liu <kernelfans@gmail.com> Cc: James Morse <james.morse@arm.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Remi Denis-Courmont <remi.denis.courmont@huawei.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: kvmarm@lists.cs.columbia.edu Link: https://lore.kernel.org/r/1598621998-20563-1-git-send-email-kernelfans@gmail.com To: linux-arm-kernel@lists.infradead.org Signed-off-by: Will Deacon <will@kernel.org>
* arm64: kernel: Convert to modern annotations for assembly functionsMark Brown2020-05-041-2/+2
| | | | | | | | | | | | | In an effort to clarify and simplify the annotation of assembly functions in the kernel new macros have been introduced. These replace ENTRY and ENDPROC and also add a new annotation for static functions which previously had no ENTRY equivalent. Update the annotations in the core kernel code to the new macros. Signed-off-by: Mark Brown <broonie@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20200501115430.37315-3-broonie@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
* arm64: use mov_q instead of literal ldrRemi Denis-Courmont2020-03-241-1/+1
| | | | | | | | | | | In practice, this requires only 2 instructions, or even only 1 for the idmap_pg_dir size (with 4 or 64 KiB pages). Only the MAIR values needed more than 2 instructions and it was already converted to mov_q by 95b3f74bec203804658e17f86fe20755bb8abcb9. Signed-off-by: Remi Denis-Courmont <remi.denis.courmont@huawei.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com>
* arm64: kernel: avoid x18 in __cpu_soft_restartArd Biesheuvel2020-01-161-2/+2
| | | | | | | | | | | | | The code in __cpu_soft_restart() uses x18 as an arbitrary temp register, which will shortly be disallowed. So use x8 instead. Link: https://patchwork.kernel.org/patch/9836877/ Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> [Sami: updated commit message] Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Will Deacon <will@kernel.org>
* treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner2019-06-191-4/+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>
* arm64: kexec_file: invoke the kernel without purgatoryAKASHI Takahiro2018-12-061-4/+4
| | | | | | | | | | | | | | | On arm64, purgatory would do almost nothing. So just invoke secondary kernel directly by jumping into its entry code. While, in this case, cpu_soft_restart() must be called with dtb address in the fifth argument, the behavior still stays compatible with kexec_load case as long as the argument is null. Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Reviewed-by: James Morse <james.morse@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
* arm64: idmap: Use "awx" flags for .idmap.text .pushsection directivesWill Deacon2018-02-061-1/+1
| | | | | | | | | | | The identity map is mapped as both writeable and executable by the SWAPPER_MM_MMUFLAGS and this is relied upon by the kpti code to manage a synchronisation flag. Update the .pushsection flags to reflect the actual mapping attributes. Reported-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* arm64: Add software workaround for Falkor erratum 1041Shanker Donthineni2018-02-061-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* arm64: Add back cpu reset routinesGeoff Levand2016-06-271-0/+54
Commit 68234df4ea79 ("arm64: kill flush_cache_all()") removed the global arm64 routines cpu_reset() and cpu_soft_restart() needed by the arm64 kexec and kdump support. Add back a simplified version of cpu_soft_restart() with some changes needed for kexec in the new files cpu_reset.S, and cpu_reset.h. When a CPU is reset it needs to be put into the exception level it had when it entered the kernel. Update cpu_soft_restart() to accept an argument which signals if the reset address should be entered at EL1 or EL2, and add a new hypercall HVC_SOFT_RESTART which is used for the EL2 switch. Signed-off-by: Geoff Levand <geoff@infradead.org> Reviewed-by: James Morse <james.morse@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>