summaryrefslogtreecommitdiff
path: root/arch/arm64/kernel/cpu_errata.c
AgeCommit message (Collapse)Author
2018-09-19arm64: cpu_errata: Remove ARM64_MISMATCHED_CACHE_LINE_SIZEWill Deacon
There's no need to treat mismatched cache-line sizes reported by CTR_EL0 differently to any other mismatched fields that we treat as "STRICT" in the cpufeature code. In both cases we need to trap and emulate EL0 accesses to the register, so drop ARM64_MISMATCHED_CACHE_LINE_SIZE and rely on ARM64_MISMATCHED_CACHE_TYPE instead. Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> [catalin.marinas@arm.com: move ARM64_HAS_CNP in the empty cpucaps.h slot] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-14arm64: cpu: Move errata and feature enable callbacks closer to callersWill Deacon
The cpu errata and feature enable callbacks are only called via their respective arm64_cpu_capabilities structure and therefore shouldn't exist in the global namespace. Move the PAN, RAS and cache maintenance emulation enable callbacks into the same files as their corresponding arm64_cpu_capabilities structures, making them static in the process. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-14arm64: ssbd: Add support for PSTATE.SSBS rather than trapping to EL3Will Deacon
On CPUs with support for PSTATE.SSBS, the kernel can toggle the SSBD state without needing to call into firmware. This patch hooks into the existing SSBD infrastructure so that SSBS is used on CPUs that support it, but it's all made horribly complicated by the very real possibility of big/little systems that don't uniformly provide the new capability. Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-07-12arm64: kill config_sctlr_el1()Mark Rutland
Now that we have sysreg_clear_set(), we can consistently use this instead of config_sctlr_el1(). Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Dave Martin <dave.martin@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-06arm64: errata: Don't define type field twice for arm64_errata[] entriesWill Deacon
The ERRATA_MIDR_REV_RANGE macro assigns ARM64_CPUCAP_LOCAL_CPU_ERRATUM to the '.type' field of the 'struct arm64_cpu_capabilities', so there's no need to assign it explicitly as well. Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-05arm64: IPI each CPU after invalidating the I-cache for kernel mappingsWill Deacon
When invalidating the instruction cache for a kernel mapping via flush_icache_range(), it is also necessary to flush the pipeline for other CPUs so that instructions fetched into the pipeline before the I-cache invalidation are discarded. For example, if module 'foo' is unloaded and then module 'bar' is loaded into the same area of memory, a CPU could end up executing instructions from 'foo' when branching into 'bar' if these instructions were fetched into the pipeline before 'foo' was unloaded. Whilst this is highly unlikely to occur in practice, particularly as any exception acts as a context-synchronizing operation, following the letter of the architecture requires us to execute an ISB on each CPU in order for the new instruction stream to be visible. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-05arm64: Handle mismatched cache typeSuzuki K Poulose
Track mismatches in the cache type register (CTR_EL0), other than the D/I min line sizes and trap user accesses if there are any. Fixes: be68a8aaf925 ("arm64: cpufeature: Fix CTR_EL0 field definitions") Cc: <stable@vger.kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-05arm64: Fix mismatched cache line size detectionSuzuki K Poulose
If there is a mismatch in the I/D min line size, we must always use the system wide safe value both in applications and in the kernel, while performing cache operations. However, we have been checking more bits than just the min line sizes, which triggers false negatives. We may need to trap the user accesses in such cases, but not necessarily patch the kernel. This patch fixes the check to do the right thing as advertised. A new capability will be added to check mismatches in other fields and ensure we trap the CTR accesses. Fixes: be68a8aaf925 ("arm64: cpufeature: Fix CTR_EL0 field definitions") Cc: <stable@vger.kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-06-08Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: "Apart from the core arm64 and perf changes, the Spectre v4 mitigation touches the arm KVM code and the ACPI PPTT support touches drivers/ (acpi and cacheinfo). I should have the maintainers' acks in place. Summary: - Spectre v4 mitigation (Speculative Store Bypass Disable) support for arm64 using SMC firmware call to set a hardware chicken bit - ACPI PPTT (Processor Properties Topology Table) parsing support and enable the feature for arm64 - Report signal frame size to user via auxv (AT_MINSIGSTKSZ). The primary motivation is Scalable Vector Extensions which requires more space on the signal frame than the currently defined MINSIGSTKSZ - ARM perf patches: allow building arm-cci as module, demote dev_warn() to dev_dbg() in arm-ccn event_init(), miscellaneous cleanups - cmpwait() WFE optimisation to avoid some spurious wakeups - L1_CACHE_BYTES reverted back to 64 (for performance reasons that have to do with some network allocations) while keeping ARCH_DMA_MINALIGN to 128. cache_line_size() returns the actual hardware Cache Writeback Granule - Turn LSE atomics on by default in Kconfig - Kernel fault reporting tidying - Some #include and miscellaneous cleanups" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (53 commits) arm64: Fix syscall restarting around signal suppressed by tracer arm64: topology: Avoid checking numa mask for scheduler MC selection ACPI / PPTT: fix build when CONFIG_ACPI_PPTT is not enabled arm64: cpu_errata: include required headers arm64: KVM: Move VCPU_WORKAROUND_2_FLAG macros to the top of the file arm64: signal: Report signal frame size to userspace via auxv arm64/sve: Thin out initialisation sanity-checks for sve_max_vl arm64: KVM: Add ARCH_WORKAROUND_2 discovery through ARCH_FEATURES_FUNC_ID arm64: KVM: Handle guest's ARCH_WORKAROUND_2 requests arm64: KVM: Add ARCH_WORKAROUND_2 support for guests arm64: KVM: Add HYP per-cpu accessors arm64: ssbd: Add prctl interface for per-thread mitigation arm64: ssbd: Introduce thread flag to control userspace mitigation arm64: ssbd: Restore mitigation status on CPU resume arm64: ssbd: Skip apply_ssbd if not using dynamic mitigation arm64: ssbd: Add global mitigation state accessor arm64: Add 'ssbd' command-line option arm64: Add ARCH_WORKAROUND_2 probing arm64: Add per-cpu infrastructure to call ARCH_WORKAROUND_2 arm64: Call ARCH_WORKAROUND_2 on transitions between EL0 and EL1 ...
2018-06-05arm64: cpu_errata: include required headersArnd Bergmann
Without including psci.h and arm-smccc.h, we now get a build failure in some configurations: arch/arm64/kernel/cpu_errata.c: In function 'arm64_update_smccc_conduit': arch/arm64/kernel/cpu_errata.c:278:10: error: 'psci_ops' undeclared (first use in this function); did you mean 'sysfs_ops'? arch/arm64/kernel/cpu_errata.c: In function 'arm64_set_ssbd_mitigation': arch/arm64/kernel/cpu_errata.c:311:3: error: implicit declaration of function 'arm_smccc_1_1_hvc' [-Werror=implicit-function-declaration] arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_WORKAROUND_2, state, NULL); Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-05-31arm64: ssbd: Restore mitigation status on CPU resumeMarc Zyngier
On a system where firmware can dynamically change the state of the mitigation, the CPU will always come up with the mitigation enabled, including when coming back from suspend. If the user has requested "no mitigation" via a command line option, let's enforce it by calling into the firmware again to disable it. Similarily, for a resume from hibernate, the mitigation could have been disabled by the boot kernel. Let's ensure that it is set back on in that case. Acked-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-05-31arm64: ssbd: Skip apply_ssbd if not using dynamic mitigationMarc Zyngier
In order to avoid checking arm64_ssbd_callback_required on each kernel entry/exit even if no mitigation is required, let's add yet another alternative that by default jumps over the mitigation, and that gets nop'ed out if we're doing dynamic mitigation. Think of it as a poor man's static key... Reviewed-by: Julien Grall <julien.grall@arm.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-05-31arm64: Add 'ssbd' command-line optionMarc Zyngier
On a system where the firmware implements ARCH_WORKAROUND_2, it may be useful to either permanently enable or disable the workaround for cases where the user decides that they'd rather not get a trap overhead, and keep the mitigation permanently on or off instead of switching it on exception entry/exit. In any case, default to the mitigation being enabled. Reviewed-by: Julien Grall <julien.grall@arm.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-05-31arm64: Add ARCH_WORKAROUND_2 probingMarc Zyngier
As for Spectre variant-2, we rely on SMCCC 1.1 to provide the discovery mechanism for detecting the SSBD mitigation. A new capability is also allocated for that purpose, and a config option. Reviewed-by: Julien Grall <julien.grall@arm.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-05-31arm64: Add per-cpu infrastructure to call ARCH_WORKAROUND_2Marc Zyngier
In a heterogeneous system, we can end up with both affected and unaffected CPUs. Let's check their status before calling into the firmware. Reviewed-by: Julien Grall <julien.grall@arm.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-05-31arm64: Call ARCH_WORKAROUND_2 on transitions between EL0 and EL1Marc Zyngier
In order for the kernel to protect itself, let's call the SSBD mitigation implemented by the higher exception level (either hypervisor or firmware) on each transition between userspace and kernel. We must take the PSCI conduit into account in order to target the right exception level, hence the introduction of a runtime patching callback. Reviewed-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Julien Grall <julien.grall@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-05-09arm64: capabilities: Add NVIDIA Denver CPU to bp_harden listDavid Gilhooley
The NVIDIA Denver CPU also needs a PSCI call to harden the branch predictor. Signed-off-by: David Gilhooley <dgilhooley@nvidia.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-04-11arm64: Move the content of bpi.S to hyp-entry.SMarc Zyngier
bpi.S was introduced as we were starting to build the Spectre v2 mitigation framework, and it was rather unclear that it would become strictly KVM specific. Now that the picture is a lot clearer, let's move the content of that file to hyp-entry.S, where it actually belong. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-04-11arm64: Get rid of __smccc_workaround_1_hvc_*Marc Zyngier
The very existence of __smccc_workaround_1_hvc_* is a thinko, as KVM will never use a HVC call to perform the branch prediction invalidation. Even as a nested hypervisor, it would use an SMC instruction. Let's get rid of it. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-04-11arm64: capabilities: Rework EL2 vector hardening entryMarc Zyngier
Since 5e7951ce19ab ("arm64: capabilities: Clean up midr range helpers"), capabilities must be represented with a single entry. If multiple CPU types can use the same capability, then they need to be enumerated in a list. The EL2 hardening stuff (which affects both A57 and A72) managed to escape the conversion in the above patch thanks to the 4.17 merge window. Let's fix it now. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-04-11arm64: KVM: Use SMCCC_ARCH_WORKAROUND_1 for Falkor BP hardeningShanker Donthineni
The function SMCCC_ARCH_WORKAROUND_1 was introduced as part of SMC V1.1 Calling Convention to mitigate CVE-2017-5715. This patch uses the standard call SMCCC_ARCH_WORKAROUND_1 for Falkor chips instead of Silicon provider service ID 0xC2001700. Cc: <stable@vger.kernel.org> # 4.14+ Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org> [maz: reworked errata framework integration] Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-04-09Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "ARM: - VHE optimizations - EL2 address space randomization - speculative execution mitigations ("variant 3a", aka execution past invalid privilege register access) - bugfixes and cleanups PPC: - improvements for the radix page fault handler for HV KVM on POWER9 s390: - more kvm stat counters - virtio gpu plumbing - documentation - facilities improvements x86: - support for VMware magic I/O port and pseudo-PMCs - AMD pause loop exiting - support for AMD core performance extensions - support for synchronous register access - expose nVMX capabilities to userspace - support for Hyper-V signaling via eventfd - use Enlightened VMCS when running on Hyper-V - allow userspace to disable MWAIT/HLT/PAUSE vmexits - usual roundup of optimizations and nested virtualization bugfixes Generic: - API selftest infrastructure (though the only tests are for x86 as of now)" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (174 commits) kvm: x86: fix a prototype warning kvm: selftests: add sync_regs_test kvm: selftests: add API testing infrastructure kvm: x86: fix a compile warning KVM: X86: Add Force Emulation Prefix for "emulate the next instruction" KVM: X86: Introduce handle_ud() KVM: vmx: unify adjacent #ifdefs x86: kvm: hide the unused 'cpu' variable KVM: VMX: remove bogus WARN_ON in handle_ept_misconfig Revert "KVM: X86: Fix SMRAM accessing even if VM is shutdown" kvm: Add emulation for movups/movupd KVM: VMX: raise internal error for exception during invalid protected mode state KVM: nVMX: Optimization: Dont set KVM_REQ_EVENT when VMExit with nested_run_pending KVM: nVMX: Require immediate-exit when event reinjected to L2 and L1 event pending KVM: x86: Fix misleading comments on handling pending exceptions KVM: x86: Rename interrupt.pending to interrupt.injected KVM: VMX: No need to clear pending NMI/interrupt on inject realmode interrupt x86/kvm: use Enlightened VMCS when running on Hyper-V x86/hyper-v: detect nested features x86/hyper-v: define struct hv_enlightened_vmcs and clean field bits ...
2018-04-04Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "Nothing particularly stands out here, probably because people were tied up with spectre/meltdown stuff last time around. Still, the main pieces are: - Rework of our CPU features framework so that we can whitelist CPUs that don't require kpti even in a heterogeneous system - Support for the IDC/DIC architecture extensions, which allow us to elide instruction and data cache maintenance when writing out instructions - Removal of the large memory model which resulted in suboptimal codegen by the compiler and increased the use of literal pools, which could potentially be used as ROP gadgets since they are mapped as executable - Rework of forced signal delivery so that the siginfo_t is well-formed and handling of show_unhandled_signals is consolidated and made consistent between different fault types - More siginfo cleanup based on the initial patches from Eric Biederman - Workaround for Cortex-A55 erratum #1024718 - Some small ACPI IORT updates and cleanups from Lorenzo Pieralisi - Misc cleanups and non-critical fixes" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (70 commits) arm64: uaccess: Fix omissions from usercopy whitelist arm64: fpsimd: Split cpu field out from struct fpsimd_state arm64: tlbflush: avoid writing RES0 bits arm64: cmpxchg: Include linux/compiler.h in asm/cmpxchg.h arm64: move percpu cmpxchg implementation from cmpxchg.h to percpu.h arm64: cmpxchg: Include build_bug.h instead of bug.h for BUILD_BUG arm64: lse: Include compiler_types.h and export.h for out-of-line LL/SC arm64: fpsimd: include <linux/init.h> in fpsimd.h drivers/perf: arm_pmu_platform: do not warn about affinity on uniprocessor perf: arm_spe: include linux/vmalloc.h for vmap() Revert "arm64: Revert L1_CACHE_SHIFT back to 6 (64-byte cache line size)" arm64: cpufeature: Avoid warnings due to unused symbols arm64: Add work around for Arm Cortex-A55 Erratum 1024718 arm64: Delay enabling hardware DBM feature arm64: Add MIDR encoding for Arm Cortex-A55 and Cortex-A35 arm64: capabilities: Handle shared entries arm64: capabilities: Add support for checks based on a list of MIDRs arm64: Add helpers for checking CPU MIDR against a range arm64: capabilities: Clean up midr range helpers arm64: capabilities: Change scope of VHE to Boot CPU feature ...
2018-03-28arm64: Add temporary ERRATA_MIDR_ALL_VERSIONS compatibility macroMarc Zyngier
MIDR_ALL_VERSIONS is changing, and won't have the same meaning in 4.17, and the right thing to use will be ERRATA_MIDR_ALL_VERSIONS. In order to cope with the merge window, let's add a compatibility macro that will allow a relatively smooth transition, and that can be removed post 4.17-rc1. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-28Revert "arm64: KVM: Use SMCCC_ARCH_WORKAROUND_1 for Falkor BP hardening"Marc Zyngier
Creates far too many conflicts with arm64/for-next/core, to be resent post -rc1. This reverts commit f9f5dc19509bbef6f5e675346f1a7d7b846bdb12. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-27arm64: cpufeature: Avoid warnings due to unused symbolsWill Deacon
An allnoconfig build complains about unused symbols due to functions that are called via conditional cpufeature and cpu_errata table entries. Annotate these as __maybe_unused if they are likely to be generic, or predicate their compilation on the same option as the table entry if they are specific to a given alternative. Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-26arm64: capabilities: Handle shared entriesSuzuki K Poulose
Some capabilities have different criteria for detection and associated actions based on the matching criteria, even though they all share the same capability bit. So far we have used multiple entries with the same capability bit to handle this. This is prone to errors, as the cpu_enable is invoked for each entry, irrespective of whether the detection rule applies to the CPU or not. And also this complicates other helpers, e.g, __this_cpu_has_cap. This patch adds a wrapper entry to cover all the possible variations of a capability by maintaining list of matches + cpu_enable callbacks. To avoid complicating the prototypes for the "matches()", we use arm64_cpu_capabilities maintain the list and we ignore all the other fields except the matches & cpu_enable. This ensures : 1) The capabilitiy is set when at least one of the entry detects 2) Action is only taken for the entries that "matches". This avoids explicit checks in the cpu_enable() take some action. The only constraint here is that, all the entries should have the same "type" (i.e, scope and conflict rules). If a cpu_enable() method is associated with multiple matches for a single capability, care should be taken that either the match criteria are mutually exclusive, or that the method is robust against being called multiple times. This also reverts the changes introduced by commit 67948af41f2e6818ed ("arm64: capabilities: Handle duplicate entries for a capability"). Cc: Robin Murphy <robin.murphy@arm.com> Reviewed-by: Dave Martin <dave.martin@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-26arm64: capabilities: Add support for checks based on a list of MIDRsSuzuki K Poulose
Add helpers for detecting an errata on list of midr ranges of affected CPUs, with the same work around. Cc: Will Deacon <will.deacon@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Dave Martin <dave.martin@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-26arm64: Add helpers for checking CPU MIDR against a rangeSuzuki K Poulose
Add helpers for checking if the given CPU midr falls in a range of variants/revisions for a given model. Cc: Will Deacon <will.deacon@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Dave Martin <dave.martin@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-26arm64: capabilities: Clean up midr range helpersSuzuki K Poulose
We are about to introduce generic MIDR range helpers. Clean up the existing helpers in erratum handling, preparing them to use generic version. Cc: Will Deacon <will.deacon@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Dave Martin <dave.martin@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-26arm64: capabilities: Add flags to handle the conflicts on late CPUSuzuki K Poulose
When a CPU is brought up, it is checked against the caps that are known to be enabled on the system (via verify_local_cpu_capabilities()). Based on the state of the capability on the CPU vs. that of System we could have the following combinations of conflict. x-----------------------------x | Type | System | Late CPU | |-----------------------------| | a | y | n | |-----------------------------| | b | n | y | x-----------------------------x Case (a) is not permitted for caps which are system features, which the system expects all the CPUs to have (e.g VHE). While (a) is ignored for all errata work arounds. However, there could be exceptions to the plain filtering approach. e.g, KPTI is an optional feature for a late CPU as long as the system already enables it. Case (b) is not permitted for errata work arounds that cannot be activated after the kernel has finished booting.And we ignore (b) for features. Here, yet again, KPTI is an exception, where if a late CPU needs KPTI we are too late to enable it (because we change the allocation of ASIDs etc). Add two different flags to indicate how the conflict should be handled. ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU - CPUs may have the capability ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU - CPUs may not have the cappability. Now that we have the flags to describe the behavior of the errata and the features, as we treat them, define types for ERRATUM and FEATURE. Cc: Will Deacon <will.deacon@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Dave Martin <dave.martin@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-26arm64: capabilities: Prepare for fine grained capabilitiesSuzuki K Poulose
We use arm64_cpu_capabilities to represent CPU ELF HWCAPs exposed to the userspace and the CPU hwcaps used by the kernel, which include cpu features and CPU errata work arounds. Capabilities have some properties that decide how they should be treated : 1) Detection, i.e scope : A cap could be "detected" either : - if it is present on at least one CPU (SCOPE_LOCAL_CPU) Or - if it is present on all the CPUs (SCOPE_SYSTEM) 2) When is it enabled ? - A cap is treated as "enabled" when the system takes some action based on whether the capability is detected or not. e.g, setting some control register, patching the kernel code. Right now, we treat all caps are enabled at boot-time, after all the CPUs are brought up by the kernel. But there are certain caps, which are enabled early during the boot (e.g, VHE, GIC_CPUIF for NMI) and kernel starts using them, even before the secondary CPUs are brought up. We would need a way to describe this for each capability. 3) Conflict on a late CPU - When a CPU is brought up, it is checked against the caps that are known to be enabled on the system (via verify_local_cpu_capabilities()). Based on the state of the capability on the CPU vs. that of System we could have the following combinations of conflict. x-----------------------------x | Type | System | Late CPU | ------------------------------| | a | y | n | ------------------------------| | b | n | y | x-----------------------------x Case (a) is not permitted for caps which are system features, which the system expects all the CPUs to have (e.g VHE). While (a) is ignored for all errata work arounds. However, there could be exceptions to the plain filtering approach. e.g, KPTI is an optional feature for a late CPU as long as the system already enables it. Case (b) is not permitted for errata work arounds which requires some work around, which cannot be delayed. And we ignore (b) for features. Here, yet again, KPTI is an exception, where if a late CPU needs KPTI we are too late to enable it (because we change the allocation of ASIDs etc). So this calls for a lot more fine grained behavior for each capability. And if we define all the attributes to control their behavior properly, we may be able to use a single table for the CPU hwcaps (which cover errata and features, not the ELF HWCAPs). This is a prepartory step to get there. More bits would be added for the properties listed above. We are going to use a bit-mask to encode all the properties of a capabilities. This patch encodes the "SCOPE" of the capability. As such there is no change in how the capabilities are treated. Cc: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Dave Martin <dave.martin@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-26arm64: capabilities: Move errata processing codeSuzuki K Poulose
We have errata work around processing code in cpu_errata.c, which calls back into helpers defined in cpufeature.c. Now that we are going to make the handling of capabilities generic, by adding the information to each capability, move the errata work around specific processing code. No functional changes. Cc: Will Deacon <will.deacon@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Dave Martin <dave.martin@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-26arm64: capabilities: Update prototype for enable call backDave Martin
We issue the enable() call back for all CPU hwcaps capabilities available on the system, on all the CPUs. So far we have ignored the argument passed to the call back, which had a prototype to accept a "void *" for use with on_each_cpu() and later with stop_machine(). However, with commit 0a0d111d40fd1 ("arm64: cpufeature: Pass capability structure to ->enable callback"), there are some users of the argument who wants the matching capability struct pointer where there are multiple matching criteria for a single capability. Clean up the declaration of the call back to make it clear. 1) Renamed to cpu_enable(), to imply taking necessary actions on the called CPU for the entry. 2) Pass const pointer to the capability, to allow the call back to check the entry. (e.,g to check if any action is needed on the CPU) 3) We don't care about the result of the call back, turning this to a void. Cc: Will Deacon <will.deacon@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Andre Przywara <andre.przywara@arm.com> Cc: James Morse <james.morse@arm.com> Acked-by: Robin Murphy <robin.murphy@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Dave Martin <dave.martin@arm.com> [suzuki: convert more users, rename call back and drop results] Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-19arm64: KVM: Use SMCCC_ARCH_WORKAROUND_1 for Falkor BP hardeningShanker Donthineni
The function SMCCC_ARCH_WORKAROUND_1 was introduced as part of SMC V1.1 Calling Convention to mitigate CVE-2017-5715. This patch uses the standard call SMCCC_ARCH_WORKAROUND_1 for Falkor chips instead of Silicon provider service ID 0xC2001700. Cc: <stable@vger.kernel.org> # 4.14+ Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19arm64: Enable ARM64_HARDEN_EL2_VECTORS on Cortex-A57 and A72Marc Zyngier
Cortex-A57 and A72 are vulnerable to the so-called "variant 3a" of Meltdown, where an attacker can speculatively obtain the value of a privileged system register. By enabling ARM64_HARDEN_EL2_VECTORS on these CPUs, obtaining VBAR_EL2 is not disclosing the hypervisor mappings anymore. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-19arm64: Make BP hardening slot counter availableMarc Zyngier
We're about to need to allocate hardening slots from other parts of the kernel (in order to support ARM64_HARDEN_EL2_VECTORS). Turn the counter into an atomic_t and make it available to the rest of the kernel. Also add BP_HARDEN_EL2_SLOTS as the number of slots instead of the hardcoded 4... Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2018-03-09arm64: Relax ARM_SMCCC_ARCH_WORKAROUND_1 discoveryMarc Zyngier
A recent update to the ARM SMCCC ARCH_WORKAROUND_1 specification allows firmware to return a non zero, positive value to describe that although the mitigation is implemented at the higher exception level, the CPU on which the call is made is not affected. Let's relax the check on the return value from ARCH_WORKAROUND_1 so that we only error out if the returned value is negative. Fixes: b092201e0020 ("arm64: Add ARM_SMCCC_ARCH_WORKAROUND_1 BP hardening support") Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-03-09arm64/kernel: enable A53 erratum #8434319 handling at runtimeArd Biesheuvel
Omit patching of ADRP instruction at module load time if the current CPUs are not susceptible to the erratum. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> [will: Drop duplicate initialisation of .def_scope field] Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-09arm64/errata: add REVIDR handling to frameworkArd Biesheuvel
In some cases, core variants that are affected by a certain erratum also exist in versions that have the erratum fixed, and this fact is recorded in a dedicated bit in system register REVIDR_EL1. Since the architecture does not require that a certain bit retains its meaning across different variants of the same model, each such REVIDR bit is tightly coupled to a certain revision/variant value, and so we need a list of revidr_mask/midr pairs to carry this information. So add the struct member and the associated macros and handling to allow REVIDR fixes to be taken into account. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-02-12arm64: Add missing Falkor part number for branch predictor hardeningShanker Donthineni
References to CPU part number MIDR_QCOM_FALKOR were dropped from the mailing list patch due to mainline/arm64 branch dependency. So this patch adds the missing part number. Fixes: ec82b567a74f ("arm64: Implement branch predictor hardening for Falkor") Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06arm64: Kill PSCI_GET_VERSION as a variant-2 workaroundMarc Zyngier
Now that we've standardised on SMCCC v1.1 to perform the branch prediction invalidation, let's drop the previous band-aid. If vendors haven't updated their firmware to do SMCCC 1.1, they haven't updated PSCI either, so we don't loose anything. Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06arm64: Add ARM_SMCCC_ARCH_WORKAROUND_1 BP hardening supportMarc Zyngier
Add the detection and runtime code for ARM_SMCCC_ARCH_WORKAROUND_1. It is lovely. Really. Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-23arm64: Branch predictor hardening for Cavium ThunderX2Jayachandran C
Use PSCI based mitigation for speculative execution attacks targeting the branch predictor. We use the same mechanism as the one used for Cortex-A CPUs, we expect the PSCI version call to have a side effect of clearing the BTBs. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Jayachandran C <jnair@caviumnetworks.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-23arm64: Run enable method for errata work arounds on late CPUsSuzuki K Poulose
When a CPU is brought up after we have finalised the system wide capabilities (i.e, features and errata), we make sure the new CPU doesn't need a new errata work around which has not been detected already. However we don't run enable() method on the new CPU for the errata work arounds already detected. This could cause the new CPU running without potential work arounds. It is upto the "enable()" method to decide if this CPU should do something about the errata. Fixes: commit 6a6efbb45b7d95c84 ("arm64: Verify CPU errata work arounds on hotplugged CPU") Cc: Will Deacon <will.deacon@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Andre Przywara <andre.przywara@arm.com> Cc: Dave Martin <dave.martin@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-14arm64: cpu_errata: Add Kryo to Falkor 1003 errataStephen Boyd
The Kryo CPUs are also affected by the Falkor 1003 errata, so we need to do the same workaround on Kryo CPUs. The MIDR is slightly more complicated here, where the PART number is not always the same when looking at all the bits from 15 to 4. Drop the lower 8 bits and just look at the top 4 to see if it's '2' and then consider those as Kryo CPUs. This covers all the combinations without having to list them all out. Fixes: 38fd94b0275c ("arm64: Work around Falkor erratum 1003") Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-08arm64: Implement branch predictor hardening for FalkorShanker Donthineni
Falkor is susceptible to branch predictor aliasing and can theoretically be attacked by malicious code. This patch implements a mitigation for these attacks, preventing any malicious entries from affecting other victim contexts. Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org> [will: fix label name when !CONFIG_KVM and remove references to MIDR_FALKOR] Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-08arm64: Implement branch predictor hardening for affected Cortex-A CPUsWill Deacon
Cortex-A57, A72, A73 and A75 are susceptible to branch predictor aliasing and can theoretically be attacked by malicious code. This patch implements a PSCI-based mitigation for these CPUs when available. The call into firmware will invalidate the branch predictor state, preventing any malicious entries from affecting other victim contexts. Co-developed-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>
2018-01-08arm64: Add skeleton to harden the branch predictor against aliasing attacksWill Deacon
Aliasing attacks against CPU branch predictors can allow an attacker to redirect speculative control flow on some CPUs and potentially divulge information from one context to another. This patch adds initial skeleton code behind a new Kconfig option to enable implementation-specific mitigations against these attacks for CPUs that are affected. Co-developed-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>
2017-06-15arm64: Add workaround for Cavium Thunder erratum 30115David Daney
Some Cavium Thunder CPUs suffer a problem where a KVM guest may inadvertently cause the host kernel to quit receiving interrupts. Use the Group-0/1 trapping in order to deal with it. [maz]: Adapted patch to the Group-0/1 trapping, reworked commit log Tested-by: Alexander Graf <agraf@suse.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: David Daney <david.daney@cavium.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <cdall@linaro.org>