'struct kobj_type' is not modified. It is only used in kobject_init()
which takes a 'const struct kobj_type *ktype' parameter.
Constifying this structure moves some data to a read-only section,
so increase over all security.
On a x86_64, compiled with arm defconfig:
Before:
======
text data bss dec hex filename
5602 548 352 6502 1966 arch/arm64/kernel/cpuinfo.o
After:
======
text data bss dec hex filename
5650 500 352 6502 1966 arch/arm64/kernel/cpuinfo.o
Signed-off-by: Huang Xiaojia <huangxiaojia2@huawei.com>
Link: https://lore.kernel.org/r/20240826151250.3500302-1-huangxiaojia2@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
* Changes to FPU handling came in via the main s390 pull request
* Only deliver to the guest the SCLP events that userspace has
requested.
* More virtual vs physical address fixes (only a cleanup since
virtual and physical address spaces are currently the same).
* Fix selftests undefined behavior.
x86:
* Fix a restriction that the guest can't program a PMU event whose
encoding matches an architectural event that isn't included in the
guest CPUID. The enumeration of an architectural event only says
that if a CPU supports an architectural event, then the event can be
programmed *using the architectural encoding*. The enumeration does
NOT say anything about the encoding when the CPU doesn't report support
the event *in general*. It might support it, and it might support it
using the same encoding that made it into the architectural PMU spec.
* Fix a variety of bugs in KVM's emulation of RDPMC (more details on
individual commits) and add a selftest to verify KVM correctly emulates
RDMPC, counter availability, and a variety of other PMC-related
behaviors that depend on guest CPUID and therefore are easier to
validate with selftests than with custom guests (aka kvm-unit-tests).
* Zero out PMU state on AMD if the virtual PMU is disabled, it does not
cause any bug but it wastes time in various cases where KVM would check
if a PMC event needs to be synthesized.
* Optimize triggering of emulated events, with a nice ~10% performance
improvement in VM-Exit microbenchmarks when a vPMU is exposed to the
guest.
* Tighten the check for "PMI in guest" to reduce false positives if an NMI
arrives in the host while KVM is handling an IRQ VM-Exit.
* Fix a bug where KVM would report stale/bogus exit qualification information
when exiting to userspace with an internal error exit code.
* Add a VMX flag in /proc/cpuinfo to report 5-level EPT support.
* Rework TDP MMU root unload, free, and alloc to run with mmu_lock held for
read, e.g. to avoid serializing vCPUs when userspace deletes a memslot.
* Tear down TDP MMU page tables at 4KiB granularity (used to be 1GiB). KVM
doesn't support yielding in the middle of processing a zap, and 1GiB
granularity resulted in multi-millisecond lags that are quite impolite
for CONFIG_PREEMPT kernels.
* Allocate write-tracking metadata on-demand to avoid the memory overhead when
a kernel is built with i915 virtualization support but the workloads use
neither shadow paging nor i915 virtualization.
* Explicitly initialize a variety of on-stack variables in the emulator that
triggered KMSAN false positives.
* Fix the debugregs ABI for 32-bit KVM.
* Rework the "force immediate exit" code so that vendor code ultimately decides
how and when to force the exit, which allowed some optimization for both
Intel and AMD.
* Fix a long-standing bug where kvm_has_noapic_vcpu could be left elevated if
vCPU creation ultimately failed, causing extra unnecessary work.
* Cleanup the logic for checking if the currently loaded vCPU is in-kernel.
* Harden against underflowing the active mmu_notifier invalidation
count, so that "bad" invalidations (usually due to bugs elsehwere in the
kernel) are detected earlier and are less likely to hang the kernel.
x86 Xen emulation:
* Overlay pages can now be cached based on host virtual address,
instead of guest physical addresses. This removes the need to
reconfigure and invalidate the cache if the guest changes the
gpa but the underlying host virtual address remains the same.
* When possible, use a single host TSC value when computing the deadline for
Xen timers in order to improve the accuracy of the timer emulation.
* Inject pending upcall events when the vCPU software-enables its APIC to fix
a bug where an upcall can be lost (and to follow Xen's behavior).
* Fall back to the slow path instead of warning if "fast" IRQ delivery of Xen
events fails, e.g. if the guest has aliased xAPIC IDs.
RISC-V:
* Support exception and interrupt handling in selftests
* New self test for RISC-V architectural timer (Sstc extension)
* New extension support (Ztso, Zacas)
* Support userspace emulation of random number seed CSRs.
ARM:
* Infrastructure for building KVM's trap configuration based on the
architectural features (or lack thereof) advertised in the VM's ID
registers
* Support for mapping vfio-pci BARs as Normal-NC (vaguely similar to
x86's WC) at stage-2, improving the performance of interacting with
assigned devices that can tolerate it
* Conversion of KVM's representation of LPIs to an xarray, utilized to
address serialization some of the serialization on the LPI injection
path
* Support for _architectural_ VHE-only systems, advertised through the
absence of FEAT_E2H0 in the CPU's ID register
* Miscellaneous cleanups, fixes, and spelling corrections to KVM and
selftests
LoongArch:
* Set reserved bits as zero in CPUCFG.
* Start SW timer only when vcpu is blocking.
* Do not restart SW timer when it is expired.
* Remove unnecessary CSR register saving during enter guest.
* Misc cleanups and fixes as usual.
Generic:
* cleanup Kconfig by removing CONFIG_HAVE_KVM, which was basically always
true on all architectures except MIPS (where Kconfig determines the
available depending on CPU capabilities). It is replaced either by
an architecture-dependent symbol for MIPS, and IS_ENABLED(CONFIG_KVM)
everywhere else.
* Factor common "select" statements in common code instead of requiring
each architecture to specify it
* Remove thoroughly obsolete APIs from the uapi headers.
* Move architecture-dependent stuff to uapi/asm/kvm.h
* Always flush the async page fault workqueue when a work item is being
removed, especially during vCPU destruction, to ensure that there are no
workers running in KVM code when all references to KVM-the-module are gone,
i.e. to prevent a very unlikely use-after-free if kvm.ko is unloaded.
* Grab a reference to the VM's mm_struct in the async #PF worker itself instead
of gifting the worker a reference, so that there's no need to remember
to *conditionally* clean up after the worker.
Selftests:
* Reduce boilerplate especially when utilize selftest TAP infrastructure.
* Add basic smoke tests for SEV and SEV-ES, along with a pile of library
support for handling private/encrypted/protected memory.
* Fix benign bugs where tests neglect to close() guest_memfd files.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm updates from Paolo Bonzini:
"S390:
- Changes to FPU handling came in via the main s390 pull request
- Only deliver to the guest the SCLP events that userspace has
requested
- More virtual vs physical address fixes (only a cleanup since
virtual and physical address spaces are currently the same)
- Fix selftests undefined behavior
x86:
- Fix a restriction that the guest can't program a PMU event whose
encoding matches an architectural event that isn't included in the
guest CPUID. The enumeration of an architectural event only says
that if a CPU supports an architectural event, then the event can
be programmed *using the architectural encoding*. The enumeration
does NOT say anything about the encoding when the CPU doesn't
report support the event *in general*. It might support it, and it
might support it using the same encoding that made it into the
architectural PMU spec
- Fix a variety of bugs in KVM's emulation of RDPMC (more details on
individual commits) and add a selftest to verify KVM correctly
emulates RDMPC, counter availability, and a variety of other
PMC-related behaviors that depend on guest CPUID and therefore are
easier to validate with selftests than with custom guests (aka
kvm-unit-tests)
- Zero out PMU state on AMD if the virtual PMU is disabled, it does
not cause any bug but it wastes time in various cases where KVM
would check if a PMC event needs to be synthesized
- Optimize triggering of emulated events, with a nice ~10%
performance improvement in VM-Exit microbenchmarks when a vPMU is
exposed to the guest
- Tighten the check for "PMI in guest" to reduce false positives if
an NMI arrives in the host while KVM is handling an IRQ VM-Exit
- Fix a bug where KVM would report stale/bogus exit qualification
information when exiting to userspace with an internal error exit
code
- Add a VMX flag in /proc/cpuinfo to report 5-level EPT support
- Rework TDP MMU root unload, free, and alloc to run with mmu_lock
held for read, e.g. to avoid serializing vCPUs when userspace
deletes a memslot
- Tear down TDP MMU page tables at 4KiB granularity (used to be
1GiB). KVM doesn't support yielding in the middle of processing a
zap, and 1GiB granularity resulted in multi-millisecond lags that
are quite impolite for CONFIG_PREEMPT kernels
- Allocate write-tracking metadata on-demand to avoid the memory
overhead when a kernel is built with i915 virtualization support
but the workloads use neither shadow paging nor i915 virtualization
- Explicitly initialize a variety of on-stack variables in the
emulator that triggered KMSAN false positives
- Fix the debugregs ABI for 32-bit KVM
- Rework the "force immediate exit" code so that vendor code
ultimately decides how and when to force the exit, which allowed
some optimization for both Intel and AMD
- Fix a long-standing bug where kvm_has_noapic_vcpu could be left
elevated if vCPU creation ultimately failed, causing extra
unnecessary work
- Cleanup the logic for checking if the currently loaded vCPU is
in-kernel
- Harden against underflowing the active mmu_notifier invalidation
count, so that "bad" invalidations (usually due to bugs elsehwere
in the kernel) are detected earlier and are less likely to hang the
kernel
x86 Xen emulation:
- Overlay pages can now be cached based on host virtual address,
instead of guest physical addresses. This removes the need to
reconfigure and invalidate the cache if the guest changes the gpa
but the underlying host virtual address remains the same
- When possible, use a single host TSC value when computing the
deadline for Xen timers in order to improve the accuracy of the
timer emulation
- Inject pending upcall events when the vCPU software-enables its
APIC to fix a bug where an upcall can be lost (and to follow Xen's
behavior)
- Fall back to the slow path instead of warning if "fast" IRQ
delivery of Xen events fails, e.g. if the guest has aliased xAPIC
IDs
RISC-V:
- Support exception and interrupt handling in selftests
- New self test for RISC-V architectural timer (Sstc extension)
- New extension support (Ztso, Zacas)
- Support userspace emulation of random number seed CSRs
ARM:
- Infrastructure for building KVM's trap configuration based on the
architectural features (or lack thereof) advertised in the VM's ID
registers
- Support for mapping vfio-pci BARs as Normal-NC (vaguely similar to
x86's WC) at stage-2, improving the performance of interacting with
assigned devices that can tolerate it
- Conversion of KVM's representation of LPIs to an xarray, utilized
to address serialization some of the serialization on the LPI
injection path
- Support for _architectural_ VHE-only systems, advertised through
the absence of FEAT_E2H0 in the CPU's ID register
- Miscellaneous cleanups, fixes, and spelling corrections to KVM and
selftests
LoongArch:
- Set reserved bits as zero in CPUCFG
- Start SW timer only when vcpu is blocking
- Do not restart SW timer when it is expired
- Remove unnecessary CSR register saving during enter guest
- Misc cleanups and fixes as usual
Generic:
- Clean up Kconfig by removing CONFIG_HAVE_KVM, which was basically
always true on all architectures except MIPS (where Kconfig
determines the available depending on CPU capabilities). It is
replaced either by an architecture-dependent symbol for MIPS, and
IS_ENABLED(CONFIG_KVM) everywhere else
- Factor common "select" statements in common code instead of
requiring each architecture to specify it
- Remove thoroughly obsolete APIs from the uapi headers
- Move architecture-dependent stuff to uapi/asm/kvm.h
- Always flush the async page fault workqueue when a work item is
being removed, especially during vCPU destruction, to ensure that
there are no workers running in KVM code when all references to
KVM-the-module are gone, i.e. to prevent a very unlikely
use-after-free if kvm.ko is unloaded
- Grab a reference to the VM's mm_struct in the async #PF worker
itself instead of gifting the worker a reference, so that there's
no need to remember to *conditionally* clean up after the worker
Selftests:
- Reduce boilerplate especially when utilize selftest TAP
infrastructure
- Add basic smoke tests for SEV and SEV-ES, along with a pile of
library support for handling private/encrypted/protected memory
- Fix benign bugs where tests neglect to close() guest_memfd files"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (246 commits)
selftests: kvm: remove meaningless assignments in Makefiles
KVM: riscv: selftests: Add Zacas extension to get-reg-list test
RISC-V: KVM: Allow Zacas extension for Guest/VM
KVM: riscv: selftests: Add Ztso extension to get-reg-list test
RISC-V: KVM: Allow Ztso extension for Guest/VM
RISC-V: KVM: Forward SEED CSR access to user space
KVM: riscv: selftests: Add sstc timer test
KVM: riscv: selftests: Change vcpu_has_ext to a common function
KVM: riscv: selftests: Add guest helper to get vcpu id
KVM: riscv: selftests: Add exception handling support
LoongArch: KVM: Remove unnecessary CSR register saving during enter guest
LoongArch: KVM: Do not restart SW timer when it is expired
LoongArch: KVM: Start SW timer only when vcpu is blocking
LoongArch: KVM: Set reserved bits as zero in CPUCFG
KVM: selftests: Explicitly close guest_memfd files in some gmem tests
KVM: x86/xen: fix recursive deadlock in timer injection
KVM: pfncache: simplify locking and make more self-contained
KVM: x86/xen: remove WARN_ON_ONCE() with false positives in evtchn delivery
KVM: x86/xen: inject vCPU upcall vector when local APIC is enabled
KVM: x86/xen: improve accuracy of Xen timers
...
The 2023 architecture extensions include a large number of floating point
features, most of which simply add new instructions. Add hwcaps so that
userspace can enumerate these features.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20240306-arm64-2023-dpisa-v5-6-c568edc8ed7f@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The 2023 architecture extensions have defined several new ID registers,
hook them up to the cpufeature code so we can add feature checks and hwcaps
based on their contents.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20240306-arm64-2023-dpisa-v5-1-c568edc8ed7f@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Add ID_AA64MMFR4_EL1 to the list of idregs the kernel knows about,
and describe the E2H0 field.
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20240122181344.258974-6-maz@kernel.org
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Since the kernel will never run on a system with the VPIPT i-cache
policy, drop the detection code altogether.
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20231204143606.1806432-3-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
FEAT_LRCPC3 adds more instructions to support the Release Consistency model.
Add a HWCAP so that userspace can make decisions about instructions it can use.
Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20230919162757.2707023-2-joey.gouly@arm.com
[catalin.marinas@arm.com: change the HWCAP number]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
SVE 2.1 introduced a new feature FEAT_SVE_B16B16 which adds instructions
supporting the BFloat16 floating point format. Report this to userspace
through the ID registers and hwcap.
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230915-arm64-zfr-b16b16-el0-v1-1-f9aba807bdb5@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Add a HWCAP for FEAT_HBC, so that userspace can make a decision on using
this feature.
Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20230804143746.3900803-2-joey.gouly@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
The Arm v8.8/9.3 FEAT_MOPS feature provides new instructions that
perform a memory copy or set. Wire up the cpufeature code to detect the
presence of FEAT_MOPS and enable it.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20230509142235.3284028-10-kristina.martsenko@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* arm64/for-next/perf:
perf: arm_spe: Print the version of SPE detected
perf: arm_spe: Add support for SPEv1.2 inverted event filtering
perf: Add perf_event_attr::config3
drivers/perf: fsl_imx8_ddr_perf: Remove set-but-not-used variable
perf: arm_spe: Support new SPEv1.2/v8.7 'not taken' event
perf: arm_spe: Use new PMSIDR_EL1 register enums
perf: arm_spe: Drop BIT() and use FIELD_GET/PREP accessors
arm64/sysreg: Convert SPE registers to automatic generation
arm64: Drop SYS_ from SPE register defines
perf: arm_spe: Use feature numbering for PMSEVFR_EL1 defines
perf/marvell: Add ACPI support to TAD uncore driver
perf/marvell: Add ACPI support to DDR uncore driver
perf/arm-cmn: Reset DTM_PMU_CONFIG at probe
drivers/perf: hisi: Extract initialization of "cpa_pmu->pmu"
drivers/perf: hisi: Simplify the parameters of hisi_pmu_init()
drivers/perf: hisi: Advertise the PERF_PMU_CAP_NO_EXCLUDE capability
* for-next/sysreg:
: arm64 sysreg and cpufeature fixes/updates
KVM: arm64: Use symbolic definition for ISR_EL1.A
arm64/sysreg: Add definition of ISR_EL1
arm64/sysreg: Add definition for ICC_NMIAR1_EL1
arm64/cpufeature: Remove 4 bit assumption in ARM64_FEATURE_MASK()
arm64/sysreg: Fix errors in 32 bit enumeration values
arm64/cpufeature: Fix field sign for DIT hwcap detection
* for-next/sme:
: SME-related updates
arm64/sme: Optimise SME exit on syscall entry
arm64/sme: Don't use streaming mode to probe the maximum SME VL
arm64/ptrace: Use system_supports_tpidr2() to check for TPIDR2 support
* for-next/kselftest: (23 commits)
: arm64 kselftest fixes and improvements
kselftest/arm64: Don't require FA64 for streaming SVE+ZA tests
kselftest/arm64: Copy whole EXTRA context
kselftest/arm64: Fix enumeration of systems without 128 bit SME for SSVE+ZA
kselftest/arm64: Fix enumeration of systems without 128 bit SME
kselftest/arm64: Don't require FA64 for streaming SVE tests
kselftest/arm64: Limit the maximum VL we try to set via ptrace
kselftest/arm64: Correct buffer size for SME ZA storage
kselftest/arm64: Remove the local NUM_VL definition
kselftest/arm64: Verify simultaneous SSVE and ZA context generation
kselftest/arm64: Verify that SSVE signal context has SVE_SIG_FLAG_SM set
kselftest/arm64: Remove spurious comment from MTE test Makefile
kselftest/arm64: Support build of MTE tests with clang
kselftest/arm64: Initialise current at build time in signal tests
kselftest/arm64: Don't pass headers to the compiler as source
kselftest/arm64: Remove redundant _start labels from FP tests
kselftest/arm64: Fix .pushsection for strings in FP tests
kselftest/arm64: Run BTI selftests on systems without BTI
kselftest/arm64: Fix test numbering when skipping tests
kselftest/arm64: Skip non-power of 2 SVE vector lengths in fp-stress
kselftest/arm64: Only enumerate power of two VLs in syscall-abi
...
* for-next/misc:
: Miscellaneous arm64 updates
arm64/mm: Intercept pfn changes in set_pte_at()
Documentation: arm64: correct spelling
arm64: traps: attempt to dump all instructions
arm64: Apply dynamic shadow call stack patching in two passes
arm64: el2_setup.h: fix spelling typo in comments
arm64: Kconfig: fix spelling
arm64: cpufeature: Use kstrtobool() instead of strtobool()
arm64: Avoid repeated AA64MMFR1_EL1 register read on pagefault path
arm64: make ARCH_FORCE_MAX_ORDER selectable
* for-next/sme2: (23 commits)
: Support for arm64 SME 2 and 2.1
arm64/sme: Fix __finalise_el2 SMEver check
kselftest/arm64: Remove redundant _start labels from zt-test
kselftest/arm64: Add coverage of SME 2 and 2.1 hwcaps
kselftest/arm64: Add coverage of the ZT ptrace regset
kselftest/arm64: Add SME2 coverage to syscall-abi
kselftest/arm64: Add test coverage for ZT register signal frames
kselftest/arm64: Teach the generic signal context validation about ZT
kselftest/arm64: Enumerate SME2 in the signal test utility code
kselftest/arm64: Cover ZT in the FP stress test
kselftest/arm64: Add a stress test program for ZT0
arm64/sme: Add hwcaps for SME 2 and 2.1 features
arm64/sme: Implement ZT0 ptrace support
arm64/sme: Implement signal handling for ZT
arm64/sme: Implement context switching for ZT0
arm64/sme: Provide storage for ZT0
arm64/sme: Add basic enumeration for SME2
arm64/sme: Enable host kernel to access ZT0
arm64/sme: Manually encode ZT0 load and store instructions
arm64/esr: Document ISS for ZT0 being disabled
arm64/sme: Document SME 2 and SME 2.1 ABI
...
* for-next/tpidr2:
: Include TPIDR2 in the signal context
kselftest/arm64: Add test case for TPIDR2 signal frame records
kselftest/arm64: Add TPIDR2 to the set of known signal context records
arm64/signal: Include TPIDR2 in the signal context
arm64/sme: Document ABI for TPIDR2 signal information
* for-next/scs:
: arm64: harden shadow call stack pointer handling
arm64: Stash shadow stack pointer in the task struct on interrupt
arm64: Always load shadow stack pointer directly from the task struct
* for-next/compat-hwcap:
: arm64: Expose compat ARMv8 AArch32 features (HWCAPs)
arm64: Add compat hwcap SSBS
arm64: Add compat hwcap SB
arm64: Add compat hwcap I8MM
arm64: Add compat hwcap ASIMDBF16
arm64: Add compat hwcap ASIMDFHM
arm64: Add compat hwcap ASIMDDP
arm64: Add compat hwcap FPHP and ASIMDHP
* for-next/ftrace:
: Add arm64 support for DYNAMICE_FTRACE_WITH_CALL_OPS
arm64: avoid executing padding bytes during kexec / hibernation
arm64: Implement HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS
arm64: ftrace: Update stale comment
arm64: patching: Add aarch64_insn_write_literal_u64()
arm64: insn: Add helpers for BTI
arm64: Extend support for CONFIG_FUNCTION_ALIGNMENT
ACPI: Don't build ACPICA with '-Os'
Compiler attributes: GCC cold function alignment workarounds
ftrace: Add DYNAMIC_FTRACE_WITH_CALL_OPS
* for-next/efi-boot-mmu-on:
: Permit arm64 EFI boot with MMU and caches on
arm64: kprobes: Drop ID map text from kprobes blacklist
arm64: head: Switch endianness before populating the ID map
efi: arm64: enter with MMU and caches enabled
arm64: head: Clean the ID map and the HYP text to the PoC if needed
arm64: head: avoid cache invalidation when entering with the MMU on
arm64: head: record the MMU state at primary entry
arm64: kernel: move identity map out of .text mapping
arm64: head: Move all finalise_el2 calls to after __enable_mmu
* for-next/ptrauth:
: arm64 pointer authentication cleanup
arm64: pauth: don't sign leaf functions
arm64: unify asm-arch manipulation
* for-next/pseudo-nmi:
: Pseudo-NMI code generation optimisations
arm64: irqflags: use alternative branches for pseudo-NMI logic
arm64: add ARM64_HAS_GIC_PRIO_RELAXED_SYNC cpucap
arm64: make ARM64_HAS_GIC_PRIO_MASKING depend on ARM64_HAS_GIC_CPUIF_SYSREGS
arm64: rename ARM64_HAS_IRQ_PRIO_MASKING to ARM64_HAS_GIC_PRIO_MASKING
arm64: rename ARM64_HAS_SYSREG_GIC_CPUIF to ARM64_HAS_GIC_CPUIF_SYSREGS
This hwcap was added for 32-bit native arm kernel by commit fea53546be
("ARM: 9274/1: Add hwcap for Speculative Store Bypassing Safe") and hence
the corresponding changes added in 32-bit compat arm64 for similar user
interfaces.
Speculative Store Bypass Safe is a feature(FEAT_SSBS) present in
AArch32/AArch64 state for Armv8 and can be identified by PFR2.SSBS
identification register. This hwcap is already advertised in native arm64
kernel.
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230111053706.13994-8-amit.kachhap@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This hwcap was added for 32-bit native arm kernel by commit
3bda6d8848 ("ARM: 9273/1: Add hwcap for Speculation Barrier(SB)")
and hence the corresponding changes added in 32-bit compat arm64 kernel.
Speculation Barrier is a feature(FEAT_SB) present in both AArch32 and
AArch64 state. This hwcap is already advertised in native arm64 kernel.
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230111053706.13994-7-amit.kachhap@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This hwcap was added earlier for 32-bit native arm kernel by commit
956ca3a4eb ("ARM: 9272/1: vfp: Add hwcap for FEAT_AA32I8MM") and hence
the corresponding changes added in 32-bit compat arm64 kernel for similar
user interfaces.
Int8 matrix multiplication is a feature (FEAT_AA32I8MM) present in AArch32
state of Armv8 and is identified by ISAR6.I8MM register. Similar
feature(FEAT_I8MM) exist for AArch64 state and is already advertised in
arm64 kernel.
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230111053706.13994-6-amit.kachhap@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This hwcap was added earlier for 32-bit native arm kernel by commit
23b6d4ad6e ("ARM: 9271/1: vfp: Add hwcap for FEAT_AA32BF16") and hence
the corresponding changes added in 32-bit compat arm64 kernel.
Brain 16-bit floating-point storage format is a feature (FEAT_AA32BF16)
present in AArch32 state for Armv8 and is represented by ISAR6.BF16
identification register. Similar feature (FEAT_BF16) exist for AArch64
state and is already advertised in native arm64 kernel.
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230111053706.13994-5-amit.kachhap@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This hwcap was added earlier for 32-bit native arm kernel by commit
ce4835497c ("ARM: 9270/1: vfp: Add hwcap for FEAT_FHM") and hence the
corresponding changes added in 32-bit compat arm64 kernel for similar user
interfaces.
Floating-point half-precision multiplication (FHM) is a feature present
in AArch32/AArch64 state for Armv8. This hwcap is already advertised in
native arm64 kernel.
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230111053706.13994-4-amit.kachhap@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This hwcap was added earlier for 32-bit native arm kernel by commit
62ea0d873a ("ARM: 9269/1: vfp: Add hwcap for FEAT_DotProd") and hence the
corresponding changes added in 32-bit compat arm64 kernel for similar user
interfaces.
Advanced Dot product is a feature (FEAT_DotProd) present in both
AArch32/AArch64 state for Armv8 and is already advertised in native arm64
kernel.
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230111053706.13994-3-amit.kachhap@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
These hwcaps were added earlier for 32-bit native arm kernel by commit
c00a19c8b1 ("ARM: 9268/1: vfp: Add hwcap FPHP and ASIMDHP for FEAT_FP16")
and hence the corresponding changes added in 32-bit compat arm64 kernel for
similar userspace interfaces.
Floating point half-precision (FPHP) and Advanced SIMD half-precision
(ASIMDHP) represents the Armv8 FP16 feature extension and is already
advertised in native arm64 kernel.
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230111053706.13994-2-amit.kachhap@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
FEAT_SVE2p1 introduces a number of new SVE instructions. Since there is no
new architectural state added kernel support is simply a new hwcap which
lets userspace know that the feature is supported.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20221017152520.1039165-6-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
FEAT_RPRFM adds a new range prefetch hint within the existing PRFM space
for range prefetch hinting. Add a new hwcap to allow userspace to discover
support for the new instruction.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20221017152520.1039165-4-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
FEAT_CSSC adds a number of new instructions usable to optimise common short
sequences of instructions, add a hwcap indicating that the feature is
available and can be used by userspace.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20221017152520.1039165-2-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
SVE has a separate identification register indicating support for BFloat16
operations. Add a hwcap identifying support for EBF16 in this register,
mirroring what we did for the non-SVE case.
While there is currently an architectural requirement for BF16 support to
be the same in SVE and non-SVE contexts there are separate identification
registers this separate hwcap helps avoid issues if that requirement were
to be relaxed in the future, we have already chosen to have a separate
capability for base BF16 support.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220829154815.832347-1-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Even if we are now able to tell the kernel to avoid exposing SVE/SME
from the command line, we still have a couple of places where we
unconditionally access the ZCR_EL1 (resp. SMCR_EL1) registers.
On systems with broken firmwares, this results in a crash even if
arm64.nosve (resp. arm64.nosme) was passed on the command-line.
To avoid this, only update cpuinfo_arm64::reg_{zcr,smcr} once
we have computed the sanitised version for the corresponding
feature registers (ID_AA64PFR0 for SVE, and ID_AA64PFR1 for
SME). This results in some minor refactoring.
Reviewed-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Peter Collingbourne <pcc@google.com>
Tested-by: Peter Collingbourne <pcc@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220720105219.1755096-1-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
* for-next/cpufeature:
arm64/hwcap: Support FEAT_EBF16
arm64/cpufeature: Store elf_hwcaps as a bitmap rather than unsigned long
arm64/hwcap: Document allocation of upper bits of AT_HWCAP
arm64: trap implementation defined functionality in userspace
The v9.2 feature FEAT_EBF16 provides support for an extended BFloat16 mode.
Allow userspace to discover system support for this feature by adding a
hwcap for it.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220707103632.12745-4-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
cache.h contains some defines which are used to represent fields and
enumeration values which do not follow the standard naming convention used for
when we automatically generate defines for system registers. Update the
names of the constants to reflect standardised naming and move them to
sysreg.h.
There is also a helper CTR_L1IP() which was open coded and has been
converted to use SYS_FIELD_GET().
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220704170302.2609529-7-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
In 155433cb36 ("arm64: cache: Remove support for ASID-tagged VIVT
I-caches") we removed all the support fir AIVIVT cache types and renamed
all references to the field to say "unknown" since support for AIVIVT
caches was removed from the architecture. Some confusion has resulted since
the corresponding change to the architecture left the value named as
AIVIVT but documented it as reserved in v8, refactor the code so we don't
define the constant instead. This will help with automatic generation of
this register field since it means we care less about the correspondence
with the ARM.
No functional change, the value displayed to userspace is unchanged.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220704170302.2609529-2-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
We currently expose MIDR and REVID to userspace through sysfs to enable it
to make decisions based on the specific implementation. Since SME supports
implementations where streaming mode is provided by a separate hardware
unit called a SMCU it provides a similar ID register SMIDR. Expose it to
userspace via sysfs when the system supports SME along with the other ID
registers.
Since we disable the SME priority mapping feature if it is supported by
hardware we currently mask out the SMPS bit which reports that it is
supported.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220607132857.1358361-1-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
* kvm-arm64/wfxt:
: .
: Add support for the WFET/WFIT instructions that provide the same
: service as WFE/WFI, only with a timeout.
: .
KVM: arm64: Expose the WFXT feature to guests
KVM: arm64: Offer early resume for non-blocking WFxT instructions
KVM: arm64: Handle blocking WFIT instruction
KVM: arm64: Introduce kvm_counter_compute_delta() helper
KVM: arm64: Simplify kvm_cpu_has_pending_timer()
arm64: Use WFxT for __delay() when possible
arm64: Add wfet()/wfit() helpers
arm64: Add HWCAP advertising FEAT_WFXT
arm64: Add RV and RN fields for ESR_ELx_WFx_ISS
arm64: Expand ESR_ELx_WFx_ISS_TI to match its ARMv8.7 definition
Signed-off-by: Marc Zyngier <maz@kernel.org>
The vector lengths used for SME are controlled through a similar set of
registers to those for SVE and enumerated using a similar algorithm with
some slight differences due to the fact that unlike SVE there are no
restrictions on which combinations of vector lengths can be supported
nor any mandatory vector lengths which must be implemented. Add a new
vector type and implement support for enumerating it.
One slightly awkward feature is that we need to read the current vector
length using a different instruction (or enter streaming mode which
would have the same issue and be higher cost). Rather than add an ops
structure we add special cases directly in the otherwise generic
vec_probe_vqs() function, this is a bit inelegant but it's the only
place where this is an issue.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220419112247.711548-10-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This patch introduces basic cpufeature support for discovering the presence
of the Scalable Matrix Extension.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220419112247.711548-9-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
In order to allow userspace to enjoy WFET, add a new HWCAP that
advertises it when available.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220419182755.601427-9-maz@kernel.org
Allow userspace to detect support for asymmetric mode by providing a hwcap
for it, using the official feature name FEAT_MTE3.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Vincenzo Frascino <Vincenzo.Frascino@arm.com>
Tested-by: Branislav Rankov <branislav.rankov@arm.com>
Link: https://lore.kernel.org/r/20220216173224.2342152-4-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Add a new HWCAP to detect the Increased precision of Reciprocal Estimate
and Reciprocal Square Root Estimate feature (FEAT_RPRES), introduced in Armv8.7.
Also expose this to userspace in the ID_AA64ISAR2_EL1 feature register.
Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211210165432.8106-4-joey.gouly@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This is a new ID register, introduced in 8.7.
Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: James Morse <james.morse@arm.com>
Cc: Alexandru Elisei <alexandru.elisei@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Reiji Watanabe <reijiw@google.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211210165432.8106-3-joey.gouly@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Add a new HWCAP to detect the Alternate Floating-point Behaviour
feature (FEAT_AFP), introduced in Armv8.7.
Also expose this to userspace in the ID_AA64MMFR1_EL1 feature register.
Signed-off-by: Joey Gouly <joey.gouly@arm.com>
Cc: Will Deacon <will@kernel.org>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211210165432.8106-2-joey.gouly@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Since userspace can make use of the CNTVSS_EL0 instruction, expose
it via a HWCAP.
Suggested-by: Will Deacon <will@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211017124225.3018098-18-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
In preparation for late initialisation of the "sanitised" AArch32 register
state, move the AArch32 registers out of 'struct cpuinfo' and into their
own struct definition.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20210608180313.11502-2-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
The GMID_EL1.BS field determines the number of tags accessed by the
LDGM/STGM instructions (EL1 and up), used by the kernel for copying or
zeroing page tags.
Taint the kernel if GMID_EL1.BS differs between CPUs but only of
CONFIG_ARM64_MTE is enabled.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Suzuki K Poulose <Suzuki.Poulose@arm.com>
Link: https://lore.kernel.org/r/20210526193621.21559-3-catalin.marinas@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
The architecture has been updated and the CTR_EL0, CNTFRQ_EL0,
DCZID_EL0, MIDR_EL1, REVIDR_EL1 registers are all 64-bit, even if most
of them have a RES0 top 32-bit.
Change their type to u64 in struct cpuinfo_arm64.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Suzuki K Poulose <Suzuki.Poulose@arm.com>
Link: https://lore.kernel.org/r/20210526193621.21559-2-catalin.marinas@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
The icache_policy_str[] definition causes a warning when extra
warning flags are enabled:
arch/arm64/kernel/cpuinfo.c:38:26: warning: initialized field overwritten [-Woverride-init]
38 | [ICACHE_POLICY_VIPT] = "VIPT",
| ^~~~~~
arch/arm64/kernel/cpuinfo.c:38:26: note: (near initialization for 'icache_policy_str[2]')
arch/arm64/kernel/cpuinfo.c:39:26: warning: initialized field overwritten [-Woverride-init]
39 | [ICACHE_POLICY_PIPT] = "PIPT",
| ^~~~~~
arch/arm64/kernel/cpuinfo.c:39:26: note: (near initialization for 'icache_policy_str[3]')
arch/arm64/kernel/cpuinfo.c:40:27: warning: initialized field overwritten [-Woverride-init]
40 | [ICACHE_POLICY_VPIPT] = "VPIPT",
| ^~~~~~~
arch/arm64/kernel/cpuinfo.c:40:27: note: (near initialization for 'icache_policy_str[0]')
There is no real need for the default initializer here, as printing a
NULL string is harmless. Rewrite the logic to have an explicit
reserved value for the only one that uses the default value.
This partially reverts the commit that removed ICACHE_POLICY_AIVIVT.
Fixes: 155433cb36 ("arm64: cache: Remove support for ASID-tagged VIVT I-caches")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20201026193807.3816388-1-arnd@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Add userspace support for the Memory Tagging Extension introduced by
Armv8.5.
(Catalin Marinas and others)
* for-next/mte: (30 commits)
arm64: mte: Fix typo in memory tagging ABI documentation
arm64: mte: Add Memory Tagging Extension documentation
arm64: mte: Kconfig entry
arm64: mte: Save tags when hibernating
arm64: mte: Enable swap of tagged pages
mm: Add arch hooks for saving/restoring tags
fs: Handle intra-page faults in copy_mount_options()
arm64: mte: ptrace: Add NT_ARM_TAGGED_ADDR_CTRL regset
arm64: mte: ptrace: Add PTRACE_{PEEK,POKE}MTETAGS support
arm64: mte: Allow {set,get}_tagged_addr_ctrl() on non-current tasks
arm64: mte: Restore the GCR_EL1 register after a suspend
arm64: mte: Allow user control of the generated random tags via prctl()
arm64: mte: Allow user control of the tag check mode via prctl()
mm: Allow arm64 mmap(PROT_MTE) on RAM-based files
arm64: mte: Validate the PROT_MTE request via arch_validate_flags()
mm: Introduce arch_validate_flags()
arm64: mte: Add PROT_MTE support to mmap() and mprotect()
mm: Introduce arch_calc_vm_flag_bits()
arm64: mte: Tags-aware aware memcmp_pages() implementation
arm64: Avoid unnecessary clear_user_page() indirection
...
HWCAP name arrays (hwcap_str, compat_hwcap_str, compat_hwcap2_str) that are
scanned for /proc/cpuinfo are detached from their bit definitions making it
vulnerable and difficult to correlate. It is also bit problematic because
during /proc/cpuinfo dump these arrays get traversed sequentially assuming
they reflect and match actual HWCAP bit sequence, to test various features
for a given CPU. This redefines name arrays per their HWCAP bit definitions
. It also warns after detecting any feature which is not expected on arm64.
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Dave Martin <Dave.Martin@arm.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Link: https://lore.kernel.org/r/1599630535-29337-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Add the cpufeature and hwcap entries to detect the presence of MTE. Any
secondary CPU not supporting the feature, if detected on the boot CPU,
will be parked.
Add the minimum SCTLR_EL1 and HCR_EL2 bits for enabling MTE. The Normal
Tagged memory type is configured in MAIR_EL1 before the MMU is enabled
in order to avoid disrupting other CPUs in the CnP domain.
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Co-developed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Suzuki K Poulose <Suzuki.Poulose@arm.com>
Fallthrough annotations for consecutive default and case labels
are not necessary.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>