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2019-08-30Merge branches 'for-next/52-bit-kva', 'for-next/cpu-topology', ↵Will Deacon
'for-next/error-injection', 'for-next/perf', 'for-next/psci-cpuidle', 'for-next/rng', 'for-next/smpboot', 'for-next/tbi' and 'for-next/tlbi' into for-next/core * for-next/52-bit-kva: (25 commits) Support for 52-bit virtual addressing in kernel space * for-next/cpu-topology: (9 commits) Move CPU topology parsing into core code and add support for ACPI 6.3 * for-next/error-injection: (2 commits) Support for function error injection via kprobes * for-next/perf: (8 commits) Support for i.MX8 DDR PMU and proper SMMUv3 group validation * for-next/psci-cpuidle: (7 commits) Move PSCI idle code into a new CPUidle driver * for-next/rng: (4 commits) Support for 'rng-seed' property being passed in the devicetree * for-next/smpboot: (3 commits) Reduce fragility of secondary CPU bringup in debug configurations * for-next/tbi: (10 commits) Introduce new syscall ABI with relaxed requirements for pointer tags * for-next/tlbi: (6 commits) Handle spurious page faults arising from kernel space
2019-08-27arm64: smp: Don't enter kernel with NULL stack pointer or task structWill Deacon
Although SMP bringup is inherently racy, we can significantly reduce the window during which secondary CPUs can unexpectedly enter the kernel by sanity checking the 'stack' and 'task' fields of the 'secondary_data' structure. If the booting CPU gave up waiting for us, then they will have been cleared to NULL and we should spin in a WFE; WFI loop instead. Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-08-09arm64: mm: Remove vabits_userSteve Capper
Previous patches have enabled 52-bit kernel + user VAs and there is no longer any scenario where user VA != kernel VA size. This patch removes the, now redundant, vabits_user variable and replaces usage with vabits_actual where appropriate. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Steve Capper <steve.capper@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-08-09arm64: mm: Introduce 52-bit Kernel VAsSteve Capper
Most of the machinery is now in place to enable 52-bit kernel VAs that are detectable at boot time. This patch adds a Kconfig option for 52-bit user and kernel addresses and plumbs in the requisite CONFIG_ macros as well as sets TCR.T1SZ, physvirt_offset and vmemmap at early boot. To simplify things this patch also removes the 52-bit user/48-bit kernel kconfig option. Signed-off-by: Steve Capper <steve.capper@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-08-09arm64: mm: Logic to make offset_ttbr1 conditionalSteve Capper
When running with a 52-bit userspace VA and a 48-bit kernel VA we offset ttbr1_el1 to allow the kernel pagetables with a 52-bit PTRS_PER_PGD to be used for both userspace and kernel. Moving on to a 52-bit kernel VA we no longer require this offset to ttbr1_el1 should we be running on a system with HW support for 52-bit VAs. This patch introduces conditional logic to offset_ttbr1 to query SYS_ID_AA64MMFR2_EL1 whenever 52-bit VAs are selected. If there is HW support for 52-bit VAs then the ttbr1 offset is skipped. We choose to read a system register rather than vabits_actual because offset_ttbr1 can be called in places where the kernel data is not actually mapped. Calls to offset_ttbr1 appear to be made from rarely called code paths so this extra logic is not expected to adversely affect performance. Signed-off-by: Steve Capper <steve.capper@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-08-09arm64: mm: Introduce vabits_actualSteve Capper
In order to support 52-bit kernel addresses detectable at boot time, one needs to know the actual VA_BITS detected. A new variable vabits_actual is introduced in this commit and employed for the KVM hypervisor layout, KASAN, fault handling and phys-to/from-virt translation where there would normally be compile time constants. In order to maintain performance in phys_to_virt, another variable physvirt_offset is introduced. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Steve Capper <steve.capper@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-08-09arm64: mm: Introduce VA_BITS_MINSteve Capper
In order to support 52-bit kernel addresses detectable at boot time, the kernel needs to know the most conservative VA_BITS possible should it need to fall back to this quantity due to lack of hardware support. A new compile time constant VA_BITS_MIN is introduced in this patch and it is employed in the KASAN end address, KASLR, and EFI stub. For Arm, if 52-bit VA support is unavailable the fallback is to 48-bits. In other words: VA_BITS_MIN = min (48, VA_BITS) Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Steve Capper <steve.capper@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-08-05arm64: Add support for relocating the kernel with RELR relocationsPeter Collingbourne
RELR is a relocation packing format for relative relocations. The format is described in a generic-abi proposal: https://groups.google.com/d/topic/generic-abi/bX460iggiKg/discussion The LLD linker can be instructed to pack relocations in the RELR format by passing the flag --pack-dyn-relocs=relr. This patch adds a new config option, CONFIG_RELR. Enabling this option instructs the linker to pack vmlinux's relative relocations in the RELR format, and causes the kernel to apply the relocations at startup along with the RELA relocations. RELA relocations still need to be applied because the linker will emit RELA relative relocations if they are unrepresentable in the RELR format (i.e. address not a multiple of 2). Enabling CONFIG_RELR reduces the size of a defconfig kernel image with CONFIG_RANDOMIZE_BASE by 3.5MB/16% uncompressed, or 550KB/5% compressed (lz4). Signed-off-by: Peter Collingbourne <pcc@google.com> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234Thomas Gleixner
Based on 1 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 distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 503 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Enrico Weigelt <info@metux.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-01arm64: Fix size of __early_cpu_boot_statusArun KS
__early_cpu_boot_status is of type long. Use quad assembler directive to allocate proper size. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Arun KS <arunks@codeaurora.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-05arm64: Use defines instead of magic numbersAlexandru Elisei
Following assembly code is not trivial; make it slightly easier to read by replacing some of the magic numbers with the defines which are already present in sysreg.h. Reviewed-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-02-20arm64: Relax GIC version check during early bootVladimir Murzin
Updates to the GIC architecture allow ID_AA64PFR0_EL1.GIC to have values other than 0 or 1. At the moment, Linux is quite strict in the way it handles this field at early boot stage (cpufeature is fine) and will refuse to use the system register CPU interface if it doesn't find the value 1. Fixes: 021f653791ad17e03f98aaa7fb933816ae16f161 ("irqchip: gic-v3: Initial support for GICv3") Reported-by: Chase Conklin <Chase.Conklin@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-01-10arm64: kpti: Avoid rewriting early page tables when KASLR is enabledWill Deacon
A side effect of commit c55191e96caa ("arm64: mm: apply r/o permissions of VM areas to its linear alias as well") is that the linear map is created with page granularity, which means that transitioning the early page table from global to non-global mappings when enabling kpti can take a significant amount of time during boot. Given that most CPU implementations do not require kpti, this mainly impacts KASLR builds where kpti is forcefully enabled. However, in these situations we know early on that non-global mappings are required and can avoid the use of global mappings from the beginning. The only gotcha is Cavium erratum #27456, which we must detect based on the MIDR value of the boot CPU. Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reported-by: John Garry <john.garry@huawei.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-12-13arm64/kvm: consistently handle host HCR_EL2 flagsMark Rutland
In KVM we define the configuration of HCR_EL2 for a VHE HOST in HCR_HOST_VHE_FLAGS, but we don't have a similar definition for the non-VHE host flags, and open-code HCR_RW. Further, in head.S we open-code the flags for VHE and non-VHE configurations. In future, we're going to want to configure more flags for the host, so lets add a HCR_HOST_NVHE_FLAGS defintion, and consistently use both HCR_HOST_VHE_FLAGS and HCR_HOST_NVHE_FLAGS in the kvm code and head.S. We now use mov_q to generate the HCR_EL2 value, as we use when configuring other registers in head.S. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: kvmarm@lists.cs.columbia.edu Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-12-10Merge branch 'for-next/kexec' into aarch64/for-next/coreWill Deacon
Merge in kexec_file_load() support from Akashi Takahiro.
2018-12-10arm64: smp: Rework early feature mismatched detectionWill Deacon
Rather than add additional variables to detect specific early feature mismatches with secondary CPUs, we can instead dedicate the upper bits of the CPU boot status word to flag specific mismatches. This allows us to communicate both granule and VA-size mismatches back to the primary CPU without the need for additional book-keeping. Tested-by: Steve Capper <steve.capper@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-12-10arm64: Kconfig: Re-jig CONFIG options for 52-bit VAWill Deacon
Enabling 52-bit VAs for userspace is pretty confusing, since it requires you to select "48-bit" virtual addressing in the Kconfig. Rework the logic so that 52-bit user virtual addressing is advertised in the "Virtual address space size" choice, along with some help text to describe its interaction with Pointer Authentication. The EXPERT-only option to force all user mappings to the 52-bit range is then made available immediately below the VA size selection. Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-12-10arm64: mm: introduce 52-bit userspace supportSteve Capper
On arm64 there is optional support for a 52-bit virtual address space. To exploit this one has to be running with a 64KB page size and be running on hardware that supports this. For an arm64 kernel supporting a 48 bit VA with a 64KB page size, some changes are needed to support a 52-bit userspace: * TCR_EL1.T0SZ needs to be 12 instead of 16, * TASK_SIZE needs to reflect the new size. This patch implements the above when the support for 52-bit VAs is detected at early boot time. On arm64 userspace addresses translation is controlled by TTBR0_EL1. As well as userspace, TTBR0_EL1 controls: * The identity mapping, * EFI runtime code. It is possible to run a kernel with an identity mapping that has a larger VA size than userspace (and for this case __cpu_set_tcr_t0sz() would set TCR_EL1.T0SZ as appropriate). However, when the conditions for 52-bit userspace are met; it is possible to keep TCR_EL1.T0SZ fixed at 12. Thus in this patch, the TCR_EL1.T0SZ size changing logic is disabled. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Steve Capper <steve.capper@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-12-10arm64: mm: Prevent mismatched 52-bit VA supportSteve Capper
For cases where there is a mismatch in ARMv8.2-LVA support between CPUs we have to be careful in allowing secondary CPUs to boot if 52-bit virtual addresses have already been enabled on the boot CPU. This patch adds code to the secondary startup path. If the boot CPU has enabled 52-bit VAs then ID_AA64MMFR2_EL1 is checked to see if the secondary can also enable 52-bit support. If not, the secondary is prevented from booting and an error message is displayed indicating why. Technically this patch could be implemented using the cpufeature code when considering 52-bit userspace support. However, we employ low level checks here as the cpufeature code won't be able to run if we have mismatched 52-bit kernel va support. Signed-off-by: Steve Capper <steve.capper@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-12-10arm64: mm: Offset TTBR1 to allow 52-bit PTRS_PER_PGDSteve Capper
Enabling 52-bit VAs on arm64 requires that the PGD table expands from 64 entries (for the 48-bit case) to 1024 entries. This quantity, PTRS_PER_PGD is used as follows to compute which PGD entry corresponds to a given virtual address, addr: pgd_index(addr) -> (addr >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1) Userspace addresses are prefixed by 0's, so for a 48-bit userspace address, uva, the following is true: (uva >> PGDIR_SHIFT) & (1024 - 1) == (uva >> PGDIR_SHIFT) & (64 - 1) In other words, a 48-bit userspace address will have the same pgd_index when using PTRS_PER_PGD = 64 and 1024. Kernel addresses are prefixed by 1's so, given a 48-bit kernel address, kva, we have the following inequality: (kva >> PGDIR_SHIFT) & (1024 - 1) != (kva >> PGDIR_SHIFT) & (64 - 1) In other words a 48-bit kernel virtual address will have a different pgd_index when using PTRS_PER_PGD = 64 and 1024. If, however, we note that: kva = 0xFFFF << 48 + lower (where lower[63:48] == 0b) and, PGDIR_SHIFT = 42 (as we are dealing with 64KB PAGE_SIZE) We can consider: (kva >> PGDIR_SHIFT) & (1024 - 1) - (kva >> PGDIR_SHIFT) & (64 - 1) = (0xFFFF << 6) & 0x3FF - (0xFFFF << 6) & 0x3F // "lower" cancels out = 0x3C0 In other words, one can switch PTRS_PER_PGD to the 52-bit value globally provided that they increment ttbr1_el1 by 0x3C0 * 8 = 0x1E00 bytes when running with 48-bit kernel VAs (TCR_EL1.T1SZ = 16). For kernel configuration where 52-bit userspace VAs are possible, this patch offsets ttbr1_el1 and sets PTRS_PER_PGD corresponding to the 52-bit value. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Steve Capper <steve.capper@arm.com> [will: added comment to TTBR1_BADDR_4852_OFFSET calculation] Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-12-06arm64: add image head flag definitionsAKASHI Takahiro
Those image head's flags will be used later by kexec_file loader. Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Acked-by: James Morse <james.morse@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-09-25arm64/mm: move runtime pgds to rodataJun Yao
Now that deliberate writes to swapper_pg_dir are made via the fixmap, we can defend against errant writes by moving it into the rodata section. Since tramp_pg_dir and reserved_ttbr0 must be at a fixed offset from swapper_pg_dir, and are not modified at runtime, these are also moved into the rodata section. Likewise, idmap_pg_dir is not modified at runtime, and is moved into rodata. Signed-off-by: Jun Yao <yaojun8558363@gmail.com> Reviewed-by: James Morse <james.morse@arm.com> [Mark: simplify linker script, commit message] Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-25arm64/mm: Separate boot-time page tables from swapper_pg_dirJun Yao
Since the address of swapper_pg_dir is fixed for a given kernel image, it is an attractive target for manipulation via an arbitrary write. To mitigate this we'd like to make it read-only by moving it into the rodata section. We require that swapper_pg_dir is at a fixed offset from tramp_pg_dir and reserved_ttbr0, so these will also need to move into rodata. However, swapper_pg_dir is allocated along with some transient page tables used for boot which we do not want to move into rodata. As a step towards this, this patch separates the boot-time page tables into a new init_pg_dir, and reduces swapper_pg_dir to the single page it needs to be. This allows us to retain the relationship between swapper_pg_dir, tramp_pg_dir, and swapper_pg_dir, while cleanly separating these from the boot-time page tables. The init_pg_dir holds all of the pgd/pud/pmd/pte levels needed during boot, and all of these levels will be freed when we switch to the swapper_pg_dir, which is initialized by the existing code in paging_init(). Since we start off on the init_pg_dir, we no longer need to allocate a transient page table in paging_init() in order to ensure that swapper_pg_dir isn't live while we initialize it. There should be no functional change as a result of this patch. Signed-off-by: Jun Yao <yaojun8558363@gmail.com> Reviewed-by: James Morse <james.morse@arm.com> [Mark: place init_pg_dir after BSS, fold mm changes, commit message] Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-25arm64/mm: Pass ttbr1 as a parameter to __enable_mmu()Jun Yao
In subsequent patches we'll use a transient pgd during the primary cpu's boot process. To make this work while allowing secondary cpus to use the swapper_pg_dir, we need to pass the relevant TTBR1 pgd as a parameter to __enable_mmu(). This patch updates __enable__mmu() to take this as a parameter, updating callsites to pass swapper_pg_dir for now. There should be no functional change as a result of this patch. Signed-off-by: Jun Yao <yaojun8558363@gmail.com> Reviewed-by: James Morse <james.morse@arm.com> [Mark: simplify assembly, clarify commit message] Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-26arm64/kvm: Prohibit guest LOR accessesMark Rutland
We don't currently limit guest accesses to the LOR registers, which we neither virtualize nor context-switch. As such, guests are provided with unusable information/controls, and are not isolated from each other (or the host). To prevent these issues, we can trap register accesses and present the illusion LORegions are unssupported by the CPU. To do this, we mask ID_AA64MMFR1.LO, and set HCR_EL2.TLOR to trap accesses to the following registers: * LORC_EL1 * LOREA_EL1 * LORID_EL1 * LORN_EL1 * LORSA_EL1 ... when trapped, we inject an UNDEFINED exception to EL1, simulating their non-existence. As noted in D7.2.67, when no LORegions are implemented, LoadLOAcquire and StoreLORelease must behave as LoadAcquire and StoreRelease respectively. We can ensure this by clearing LORC_EL1.EN when a CPU's EL2 is first initialized, as the host kernel will not modify this. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Vladimir Murzin <vladimir.murzin@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoffer Dall <christoffer.dall@linaro.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: kvmarm@lists.cs.columbia.edu Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-02-06arm64: idmap: Use "awx" flags for .idmap.text .pushsection directivesWill Deacon
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>
2018-02-06arm64: assembler: Align phys_to_pte with pte_to_physWill Deacon
pte_to_phys lives in assembler.h and takes its destination register as the first argument. Move phys_to_pte out of head.S to sit with its counterpart and rejig it to follow the same calling convention. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06arm64: assembler: Change order of macro arguments in phys_to_ttbrWill Deacon
Since AArch64 assembly instructions take the destination register as their first operand, do the same thing for the phys_to_ttbr macro. Acked-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06arm64: Add software workaround for Falkor erratum 1041Shanker Donthineni
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>
2018-01-16arm64: sysreg: Move to use definitions for all the SCTLR bitsJames Morse
__cpu_setup() configures SCTLR_EL1 using some hard coded hex masks, and el2_setup() duplicates some this when setting RES1 bits. Lets make this the same as KVM's hyp_init, which uses named bits. First, we add definitions for all the SCTLR_EL{1,2} bits, the RES{1,0} bits, and those we want to set or clear. Add a build_bug checks to ensures all bits are either set or clear. This means we don't need to preserve endian-ness configuration generated elsewhere. Finally, move the head.S and proc.S users of these hard-coded masks over to the macro versions. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-14arm64: Extend early page table code to allow for larger kernelsSteve Capper
Currently the early assembler page table code assumes that precisely 1xpgd, 1xpud, 1xpmd are sufficient to represent the early kernel text mappings. Unfortunately this is rarely the case when running with a 16KB granule, and we also run into limits with 4KB granule when building much larger kernels. This patch re-writes the early page table logic to compute indices of mappings for each level of page table, and if multiple indices are required, the next-level page table is scaled up accordingly. Also the required size of the swapper_pg_dir is computed at link time to cover the mapping [KIMAGE_ADDR + VOFFSET, _end]. When KASLR is enabled, an extra page is set aside for each level that may require extra entries at runtime. Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Steve Capper <steve.capper@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-22arm64: allow ID map to be extended to 52 bitsKristina Martsenko
Currently, when using VA_BITS < 48, if the ID map text happens to be placed in physical memory above VA_BITS, we increase the VA size (up to 48) and create a new table level, in order to map in the ID map text. This is okay because the system always supports 48 bits of VA. This patch extends the code such that if the system supports 52 bits of VA, and the ID map text is placed that high up, then we increase the VA size accordingly, up to 52. One difference from the current implementation is that so far the condition of VA_BITS < 48 has meant that the top level table is always "full", with the maximum number of entries, and an extra table level is always needed. Now, when VA_BITS = 48 (and using 64k pages), the top level table is not full, and we simply need to increase the number of entries in it, instead of creating a new table level. Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Bob Picco <bob.picco@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> [catalin.marinas@arm.com: reduce arguments to __create_hyp_mappings()] [catalin.marinas@arm.com: reworked/renamed __cpu_uses_extended_idmap_level()] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-22arm64: handle 52-bit physical addresses in page table entriesKristina Martsenko
The top 4 bits of a 52-bit physical address are positioned at bits 12..15 of a page table entry. Introduce macros to convert between a physical address and its placement in a table entry, and change all macros/functions that access PTEs to use them. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Tested-by: Bob Picco <bob.picco@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> [catalin.marinas@arm.com: some long lines wrapped] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-22arm64: head.S: handle 52-bit PAs in PTEs in early page table setupKristina Martsenko
The top 4 bits of a 52-bit physical address are positioned at bits 12..15 in page table entries. Introduce a macro to move the bits there, and change the early ID map and swapper table setup code to use it. Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Bob Picco <bob.picco@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> [catalin.marinas@arm.com: additional comments for clarification] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-22arm64: handle 52-bit addresses in TTBRKristina Martsenko
The top 4 bits of a 52-bit physical address are positioned at bits 2..5 in the TTBR registers. Introduce a couple of macros to move the bits there, and change all TTBR writers to use them. Leave TTBR0 PAN code unchanged, to avoid complicating it. A system with 52-bit PA will have PAN anyway (because it's ARMv8.1 or later), and a system without 52-bit PA can only use up to 48-bit PAs. A later patch in this series will add a kconfig dependency to ensure PAN is configured. In addition, when using 52-bit PA there is a special alignment requirement on the top-level table. We don't currently have any VA_BITS configuration that would violate the requirement, but one could be added in the future, so add a compile-time BUG_ON to check for it. Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Bob Picco <bob.picco@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> [catalin.marinas@arm.com: added TTBR_BADD_MASK_52 comment] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-11-03arm64/sve: Low-level CPU setupDave Martin
To enable the kernel to use SVE, SVE traps from EL1 to EL2 must be disabled. To take maximum advantage of the hardware, the full available vector length also needs to be enabled for EL1 by programming ZCR_EL2.LEN. (The kernel will program ZCR_EL1.LEN as required, but this cannot override the limit set by ZCR_EL2.) This patch makes the appropriate changes to the EL2 early setup code. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-18arm64: head: Init PMSCR_EL2.{PA,PCT} when entered at EL2 without VHEWill Deacon
When booting at EL2, ensure that we permit the EL1 host to sample physical addresses and physical counter values using SPE. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-09-27arm64: Make sure SPsel is always setMarc Zyngier
When the kernel is entered at EL2 on an ARMv8.0 system, we construct the EL1 pstate and make sure this uses the the EL1 stack pointer (we perform an exception return to EL1h). But if the kernel is either entered at EL1 or stays at EL2 (because we're on a VHE-capable system), we fail to set SPsel, and use whatever stack selection the higher exception level has choosen for us. Let's not take any chance, and make sure that SPsel is set to one before we decide the mode we're going to run in. Cc: <stable@vger.kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-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>
2017-09-05Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: - VMAP_STACK support, allowing the kernel stacks to be allocated in the vmalloc space with a guard page for trapping stack overflows. One of the patches introduces THREAD_ALIGN and changes the generic alloc_thread_stack_node() to use this instead of THREAD_SIZE (no functional change for other architectures) - Contiguous PTE hugetlb support re-enabled (after being reverted a couple of times). We now have the semantics agreed in the generic mm layer together with API improvements so that the architecture code can detect between contiguous and non-contiguous huge PTEs - Initial support for persistent memory on ARM: DC CVAP instruction exposed to user space (HWCAP) and the in-kernel pmem API implemented - raid6 improvements for arm64: faster algorithm for the delta syndrome and implementation of the recovery routines using Neon - FP/SIMD refactoring and removal of support for Neon in interrupt context. This is in preparation for full SVE support - PTE accessors converted from inline asm to cmpxchg so that we can use LSE atomics if available (ARMv8.1) - Perf support for Cortex-A35 and A73 - Non-urgent fixes and cleanups * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (75 commits) arm64: cleanup {COMPAT_,}SET_PERSONALITY() macro arm64: introduce separated bits for mm_context_t flags arm64: hugetlb: Cleanup setup_hugepagesz arm64: Re-enable support for contiguous hugepages arm64: hugetlb: Override set_huge_swap_pte_at() to support contiguous hugepages arm64: hugetlb: Override huge_pte_clear() to support contiguous hugepages arm64: hugetlb: Handle swap entries in huge_pte_offset() for contiguous hugepages arm64: hugetlb: Add break-before-make logic for contiguous entries arm64: hugetlb: Spring clean huge pte accessors arm64: hugetlb: Introduce pte_pgprot helper arm64: hugetlb: set_huge_pte_at Add WARN_ON on !pte_present arm64: kexec: have own crash_smp_send_stop() for crash dump for nonpanic cores arm64: dma-mapping: Mark atomic_pool as __ro_after_init arm64: dma-mapping: Do not pass data to gen_pool_set_algo() arm64: Remove the !CONFIG_ARM64_HW_AFDBM alternative code paths arm64: Ignore hardware dirty bit updates in ptep_set_wrprotect() arm64: Move PTE_RDONLY bit handling out of set_pte_at() kvm: arm64: Convert kvm_set_s2pte_readonly() from inline asm to cmpxchg() arm64: Convert pte handling from inline asm to using (cmp)xchg arm64: neon/efi: Make EFI fpsimd save/restore variables static ...
2017-08-22arm64: kaslr: ignore modulo offset when validating virtual displacementArd Biesheuvel
In the KASLR setup routine, we ensure that the early virtual mapping of the kernel image does not cover more than a single table entry at the level above the swapper block level, so that the assembler routines involved in setting up this mapping can remain simple. In this calculation we add the proposed KASLR offset to the values of the _text and _end markers, and reject it if they would end up falling in different swapper table sized windows. However, when taking the addresses of _text and _end, the modulo offset (the physical displacement modulo 2 MB) is already accounted for, and so adding it again results in incorrect results. So disregard the modulo offset from the calculation. Fixes: 08cdac619c81 ("arm64: relocatable: deal with physically misaligned ...") Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-08-09Merge branch 'arm64/exception-stack' of ↵Catalin Marinas
git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux into for-next/core * 'arm64/exception-stack' of git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux: arm64: unwind: remove sp from struct stackframe arm64: unwind: reference pt_regs via embedded stack frame arm64: unwind: disregard frame.sp when validating frame pointer arm64: unwind: avoid percpu indirection for irq stack arm64: move non-entry code out of .entry.text arm64: consistently use bl for C exception entry arm64: Add ASM_BUG()
2017-08-09arm64: unwind: reference pt_regs via embedded stack frameArd Biesheuvel
As it turns out, the unwind code is slightly broken, and probably has been for a while. The problem is in the dumping of the exception stack, which is intended to dump the contents of the pt_regs struct at each level in the call stack where an exception was taken and routed to a routine marked as __exception (which means its stack frame is right below the pt_regs struct on the stack). 'Right below the pt_regs struct' is ill defined, though: the unwind code assigns 'frame pointer + 0x10' to the .sp member of the stackframe struct at each level, and dump_backtrace() happily dereferences that as the pt_regs pointer when encountering an __exception routine. However, the actual size of the stack frame created by this routine (which could be one of many __exception routines we have in the kernel) is not known, and so frame.sp is pretty useless to figure out where struct pt_regs really is. So it seems the only way to ensure that we can find our struct pt_regs when walking the stack frames is to put it at a known fixed offset of the stack frame pointer that is passed to such __exception routines. The simplest way to do that is to put it inside pt_regs itself, which is the main change implemented by this patch. As a bonus, doing this allows us to get rid of a fair amount of cruft related to walking from one stack to the other, which is especially nice since we intend to introduce yet another stack for overflow handling once we add support for vmapped stacks. It also fixes an inconsistency where we only add a stack frame pointing to ELR_EL1 if we are executing from the IRQ stack but not when we are executing from the task stack. To consistly identify exceptions regs even in the presence of exceptions taken from entry code, we must check whether the next frame was created by entry text, rather than whether the current frame was crated by exception text. To avoid backtracing using PCs that fall in the idmap, or are controlled by userspace, we must explcitly zero the FP and LR in startup paths, and must ensure that the frame embedded in pt_regs is zeroed upon entry from EL0. To avoid these NULL entries showin in the backtrace, unwind_frame() is updated to avoid them. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> [Mark: compare current frame against .entry.text, avoid bogus PCs] Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Will Deacon <will.deacon@arm.com>
2017-08-09arm64: Convert __inval_cache_range() to area-basedRobin Murphy
__inval_cache_range() is already the odd one out among our data cache maintenance routines as the only remaining range-based one; as we're going to want an invalidation routine to call from C code for the pmem API, let's tweak the prototype and name to bring it in line with the clean operations, and to make its relationship with __dma_inv_area() neatly mirror that of __clean_dcache_area_poc() and __dma_clean_area(). The loop clearing the early page tables gets mildly massaged in the process for the sake of consistency. Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-04-04Merge branch 'arm64/common-sysreg' of ↵Catalin Marinas
git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux into for-next/core * 'arm64/common-sysreg' of git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux: arm64: sysreg: add Set/Way sys encodings arm64: sysreg: add register encodings used by KVM arm64: sysreg: add physical timer registers arm64: sysreg: subsume GICv3 sysreg definitions arm64: sysreg: add performance monitor registers arm64: sysreg: add debug system registers arm64: sysreg: sort by encoding
2017-04-04arm64: efi: clean up Image header after PE header has been split offArd Biesheuvel
After having split off the PE header, clean up the bits that remain: use .long consistently, merge two adjacent #ifdef CONFIG_EFI blocks, fix the offset of the PE header pointer and remove the redundant .align that follows it. Also, since we will be eliminating all open coded constants from the EFI header in subsequent patches, let's replace the open coded "ARM\x64" magic number with its .ascii equivalent. No changes to the resulting binary image are intended. Acked-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>
2017-04-04arm64: efi: move EFI header and related data to a separate .S fileArd Biesheuvel
In preparation of yet another round of modifications to the PE/COFF header, macroize it and move the definition into a separate source file. Acked-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>
2017-03-22arm64: move !VHE work to end of el2_setupMark Rutland
We only need to initialise sctlr_el1 if we're installing an EL2 stub, so we may as well defer this until we're doing so. Similarly, we can defer intialising CPTR_EL2 until then, as we do not access any trapped functionality as part of el2_setup. This patch modified el2_setup accordingly, allowing us to remove a branch and simplify the code flow. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-22arm64: reduce el2_setup branchingMark Rutland
The early el2_setup code is a little convoluted, with two branches where one would do. This makes the code more painful to read than is necessary. We can remove a branch and simplify the logic by moving the early return in the booted-at-EL1 case earlier in the function. This separates it from all the setup logic that only makes sense for EL2. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-09arm64: sysreg: subsume GICv3 sysreg definitionsMark Rutland
Unlike most sysreg defintiions, the GICv3 definitions don't have a SYS_ prefix, and they don't live in <asm/sysreg.h>. Additionally, some definitions are duplicated elsewhere (e.g. in the KVM save/restore code). For consistency, and to make it possible to share a common definition for these sysregs, this patch moves the definitions to <asm/sysreg.h>, adding a SYS_ prefix, and sorting the registers per their encoding. Existing users of the definitions are fixed up so that this change is not problematic. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Will Deacon <will.deacon@arm.com>
2017-02-09arm64: head.S: Enable EL1 (host) access to SPE when entered at EL2Will Deacon
The SPE architecture requires each exception level to enable access to the SPE controls for the exception level below it, since additional context-switch logic may be required to handle the buffer safely. This patch allows EL1 (host) access to the SPE controls when entered at EL2. Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>