Changes in mpam_fb.c

303bff3637d13f0ecbb280c7cb403470c440a2a6 - Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Tue, 20 Oct 2026 19:55:19 +0200

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linuxPull arm64 updates from Catalin Marinas: "Here are the arm64 updates for 7.4. The more interesting bits are the removal of big-endian kernel support (already marked BROKEN for some time), preemptible this_cpu_*() operations and MPAM support for the firmware-backed (Fb) interface. CCA (Arm's confidential compute) is slowly trickling in with host RMI (Realm Management Interface) support and some refactoring, including a dedicated SMCCC bus to advertise firmware services. There are also the usual PMU updates for new hardware and a few fixes/cleanups. Core features: - Remove big-endian kernel support: CONFIG_CPU_BIG_ENDIAN has depended on BROKEN for a while, so drop the remaining code (BE hypervisor object, BPF JIT, assembly/crypto/library routines, endianness helper macros, selftests) and force a little-endian build - Add preemptible this_cpu_*() operations (read/write, RMW, xchg, cmpxchg and cmpxchg128) that no longer need to disable preemption around the per-CPU address generation and access - Preparation patches for implementing CONFIG_HOTPLUG_PARALLEL on arm64 Memory management: - Treat faults taken by EFI runtime firmware as kernel faults - Clear PTE_WRITE for EFI_MEMORY_RO mappings (with hardware dirty state management enabled, this is not truly read-only) - Raise the default ARCH_MMAP_RND_BITS for 48-bit and 52-bit VA configurations (28/26/24 bits for 4K/16K/64K pages) - Implement clear_page[s]() using memset() - Enable BBML2 no-abort (a.k.a. BBML3) for the NVIDIA Rigel CPU Perf and PMU: - Support for HiSilicon's ITS PMU - Add support for some new events: INST_SIMD_ALU_VEC for Apple PMUs and a cycle counter for the latest version of HiSilicon's MN PMU hardware - A bunch of fixes to the CXL PMU driver to address pre-existing issues from Sashiko - Fix generation of PERF_RECORD_ITRACE_START records for SPE and ETM drivers - Reduce excessive stack consumption in the Marvell DDR PMU driver - Minor driver updates and cleanups all over Arm Confidential Compute Architecture (CCA): - Add an Arm SMCCC bus for firmware services discovered through SMCCC and move the TRNG and CCA guest (TSM provider) drivers onto it, removing the dummy CCA platform device and adding a sysfs ABI for Realm guests - Move the Realm Service Interface (RSI) code out of arch/arm64/ into drivers/firmware/arm_rmm/ - Add the host side of the Realm Management Interface (RMI): detect, configure and activate the RMM, add SRO support and wrappers for the Realm RMI commands - Block hibernation (new arch hook in the PM core) and kexec while the RMM is active. To be revisited in the future with proper support for deactivation - Handle Granule Protection Faults (GPFs) taken by the host, caused by accesses to memory delegated to the RMM. In a future patch, the exception table lookup will be limited to is_kdump_kernel() cases MPAM (Memory Partitioning And Monitoring): - Add support for the MPAM firmware-backed (Fb) interface, allowing MSC accesses to be mediated by firmware - Fix a list of theoretical issues with the driver (MSC access error propagation, MBWU monitor save/restore and locking, resctrl class handling, error interrupt restore, maximum number of PARTIDs) - Add the mailing list and a missing file to the MAINTAINERS entry - Document when to set arm64.nompam Errata and CPU features: - Add the NXP i.MX8QM/8QP workaround for the Cortex-A53 cache coherency issue (ERR050104), using a new ARM64_CPUCAP_SOC_ERRATUM capability type for SoC-level errata Miscellaneous: - Mask debug exceptions (DAIF) around the hardware breakpoint register manipulations when called from generic kernel code - Don't zero the SVE state buffer when the SVE state is live - Return -EPERM instead of -EBUSY from the GCS prctl() locking failures (matching x86), with the selftest updated. Slight ABI change but no software deployment yet - kselftest: fix unsound MTE fault skipping by introducing MTE-safe memory accessors, avoid copying each signal test binary more than once - Update sysreg definitions (fix three enum values and two field names, mark architecturally dropped fields as RES0) and remove the TME transaction state check from the BRBE driver - Fix the description of ARM64_HAS_LPA2 and remove a redundant ID_AA64MMFR0 define"* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (144 commits) arm64: cpufeature: Enable BBML2 for NVIDIA Rigel arm64: cputype: Add NVIDIA Rigel definitions arm64: raise default ARCH_MMAP_RND_BITS for 48-bit and 52-bit VA arm64/debug: mask debug exceptions when called from common code kselftest/arm64: signal: copy each test binary only once kselftest/arm64: Check for -EPERM not -EBUSY in the locking test arm64: gcs: Return -EPERM not -EBUSY for prctl() locking failures perf: arm_brbe: Remove the check for TME transaction states arm64: sysreg: Mark fields the architecture dropped as RES0 arm64: sysreg: Fix the names of two misspelt fields arm64: sysreg: Fix three incorrect enum values arm64: smp: Defer RCU registration during secondary CPU bringup arm64: smp: Don't bother printing the I-cache policy for each CPU arm64: smp: Defer update of secondary CPU capabilities arm64: smp: Tidy up cpuinfo init and cpufeature updates arm64: smp: Tidy up smp_prepare_cpus() arm64: cpufeature: Store every ID register with its overrides applied arm64: cpufeature: Read MPAMIDR_EL1 in __cpuinfo_store_cpu() arm64: cpufeature: Add read_cpuid_with_overrides() arm64: cpufeature: Check arm64_ftr_regs[] before the first store ... List of files: /linux/drivers/resctrl/mpam_fb.c

34fa781e25a6caa8862acd923e89d08cd9a9f37e - Merge branches 'for-next/misc', 'for-next/be-gone', 'for-next/smccc-bus', 'for-next/preemptible-this-cpu', 'for-next/cpu-errata', 'for-next/mpam', 'for-next/kselftest', 'for-next/efi', 'for-next/secondary-boot-prep', 'for-next/sysreg' and 'for-next/gcs', remote-tracking branch 'arm64/for-next/perf' into for-next/core

Thu, 15 Oct 2026 20:09:10 +0200

Merge branches 'for-next/misc', 'for-next/be-gone', 'for-next/smccc-bus', 'for-next/preemptible-this-cpu', 'for-next/cpu-errata', 'for-next/mpam', 'for-next/kselftest', 'for-next/efi', 'for-next/secondary-boot-prep', 'for-next/sysreg' and 'for-next/gcs', remote-tracking branch 'arm64/for-next/perf' into for-next/core* arm64/for-next/perf: (22 commits) drivers/perf: apple_m1: Add macOS 27 M2 Event perf/marvell: cn10k_tad: Publish the OF module alias perf: xgene: initialize lock before requesting IRQ perf: marvell: avoid large stack variables perf/dwc_pcie: Fix PCI device reference leak in probe coresight: perf: Suppress ITRACE start records perf: arm_spe: Suppress redundant ITRACE start records perf/core: Export perf_event_itrace_started() perf/cxl: Clear stale overflow status before using a counter perf/cxl: Don't log through pmu.dev in the overflow interrupt handler perf/cxl: Validate the hardware-reported counter width perf/cxl: Unfreeze counters after handling an overflow interrupt perf/cxl: Don't share the overflow interrupt, and keep it pinned cxl/pci: Add the PMUs after configuring events perf/cxl: Split the MSI vector out of info->irq perf/cxl: Accept an overflow interrupt on MSI message number 0 perf/cxl: Fix the counter overflow delta fixup perf/cxl: Clear stale event fields before reprogramming a counter perf/cxl: Program the requested event group on configurable counters drivers/perf: hisi: Add cycle event for new MN PMU ...* for-next/misc: arm64: cpufeature: Enable BBML2 for NVIDIA Rigel arm64: cputype: Add NVIDIA Rigel definitions arm64: raise default ARCH_MMAP_RND_BITS for 48-bit and 52-bit VA arm64/debug: mask debug exceptions when called from common code arm64: clear_page[s] using memset arm64/sve: Don't zero the SVE state buffer when the SVE state is live arm64/cpufeature: Drop redundant define(ID_AA64MMFR0..._SUPPORTED_LPA2) arm64: Use proper include variant arm64: include: fix repeated word 'to' in comment selftests: arm64: fix typo "hander" in comment arm64: fix typos in comments docs: arm64: Fix typo "initalised" in booting.rst arm64: alternative: Remove 'cfg' parameter arm64: mte-kasan: Use IS_ENABLED() rather than ALTERNATIVE() 'cfg' parameter arm64/cpufeature: Change description for ARM64_HAS_LPA2* for-next/be-gone: drivers: Kconfig: Simplify dependencies on ARM64 && !CPU_BIG_ENDIAN arm64: Kbuild: Remove vestigial big-endian support gve: Add explicit ARM64 dependency to Kconfig crypto: hisilicon/sec2: Remove check of CONFIG_CPU_LITTLE_ENDIAN arm64: Remove all usage of __AARCH64EB__ arm64: Remove all usage of CONFIG_CPU_BIG_ENDIAN KVM: arm64: Remove support for a big-endian hypervisor object arm64: vdso32: Always build compat vDSO object as little-endian arm64: assembler: Remove endianness helper macros arm64: lib: Assume a little-endian kernel in optimised string routines arm64: lib: Assume a little-endian kernel in custom library routines arm64: crypto: Assume a little-endian kernel arm64: bpf: Remove big-endian support from the JIT compiler selftests/arm64: Remove big-endian support* for-next/smccc-bus: : Switch Arm SMCCC firmware services to an SMCCC bus arm64: rsi: Correct type of realm_config::hash_algo firmware: smccc: Pass only the required device probe arguments firmware: arm_rmm: Add SPDX and sort the Kconfig and Makefile entries coco: guest: arm64: Remove dummy CCA platform device coco: guest: arm64: Add sysfs ABI for CCA Realm guests firmware: smccc: arm-cca-guest: Bind the TSM provider to an SMCCC device virt: coco: arm-cca-guest: Rename TSM report source file arm64: realm: Move Realm memory encryption ops to RSI code firmware: arm_rmm: Move RSI support out of arch/arm64 firmware: hwrng: arm_smccc_trng: Register as an SMCCC device firmware: smccc: Add an Arm SMCCC bus* for-next/preemptible-this-cpu: : Preemptible this_cpu_*() operations arm64: percpu: Remove _pcp_protect*() wrappers arm64: percpu: Implement preemptible CMPXCHG128 ops arm64: percpu: Implement preemptible CMPXCHG ops arm64: percpu: Implement preemptible XCHG ops arm64: percpu: Implement preemptible return RMW ops arm64: percpu: Implement preemptible void RMW ops arm64: percpu: Implement preemptible read/write ops arm64: percpu: Add infrastructure for preemptible this_cpu_*() ops arm64: entry: sdei: Make 'tsk' available arm64: entry: sdei: Restore all clobberable GPRs arm64: gpr-num: add __GPR_NUM() helper arm64: gpr-num: Add wxN aliases for wN registers arm64: percpu: Factor out percpu offset asm arm64: ptrace: Always inline pt_regs_{read,write}_reg() arm64: preempt: Treat should_resched() as unlikely arm64: preempt: Simplify and optimize __preempt_count_dec_and_test() arm64: cmpxchg128: LSE: Remove redundant operands arm64: cmpxchg: LL/SC: Avoid redundant extension* for-next/cpu-errata: : Various CPU errata workarounds arm64: errata: Add NXP i.MX8QM/8QP workaround for A53 cache coherency issue arm64: cpufeature: Add ARM64_CPUCAP_SOC_ERRATUM for SoC-level errata* for-next/mpam: (30 commits) : MPAM updates arm_mpam: make the mon_sel guard conditional only arm_mpam: On saving mbwu state read the monitors before clearing CFG_MBWU_CTL arm_mpam: detect and enable MPAM-Fb PCC support arm_mpam: change MPAM-Fb error IRQ to use a threaded IRQ handler arm_mpam: add MPAM-Fb MSC firmware access support arm_mpam: prepare mon_sel locking for MPAM-Fb arm_mpam: propagate MSC access errors in mpam_reset_class_locked() arm_mpam: propagate MSC access errors for interrupt control arm_mpam: propagate MSC access errors for mpam_reprogram_ris_partid() arm_mpam: propagate MSC access errors for state saving function arm_mpam: propagate MSC access errors for __ris_msmon_read() arm_mpam: propagate MSC access errors for msmon helpers arm_mpam: propagate MSC access errors for MBWU counters arm_mpam: propagate MSC access errors for hw_probe functions arm_mpam: let low level MSC accessors return an error MAINTAINERS: Use linux-arm-kernel list for the MPAM driver MAINTAINERS: Add mpam.rst to the MPAM DRIVER entry arm_mpam: resctrl: Don't stop early when tearing down a class arm_mpam: Switch to kvzmalloc_objs() for allocation of component cfg arm_mpam: Don't loop forever if there is the maximum possible amount of PARTIDs ...* for-next/kselftest: : arm64 kselftest updates kselftest/arm64: signal: copy each test binary only once kselftest/arm64/mte: Use MTE safe memory accessors kselftest/arm64/mte: Introduce MTE safe memory accessors kselftest/arm64: Extend gcs-locking to cover cases where enable is unlocked* for-next/efi: : arm64 EFI updates/fixes arm64/mm: Treat faults taken by EFI runtime firmware as kernel faults arm64/efi: Clear PTE_WRITE when applying EFI_MEMORY_RO* for-next/secondary-boot-prep: : cpuinfo cleanup in preparation for parallel secondary bring-up arm64: smp: Defer RCU registration during secondary CPU bringup arm64: smp: Don't bother printing the I-cache policy for each CPU arm64: smp: Defer update of secondary CPU capabilities arm64: smp: Tidy up cpuinfo init and cpufeature updates arm64: smp: Tidy up smp_prepare_cpus() arm64: cpufeature: Store every ID register with its overrides applied arm64: cpufeature: Read MPAMIDR_EL1 in __cpuinfo_store_cpu() arm64: cpufeature: Add read_cpuid_with_overrides() arm64: cpufeature: Check arm64_ftr_regs[] before the first store* for-next/sysreg: : sysreg updates perf: arm_brbe: Remove the check for TME transaction states arm64: sysreg: Mark fields the architecture dropped as RES0 arm64: sysreg: Fix the names of two misspelt fields arm64: sysreg: Fix three incorrect enum values* for-next/gcs: : GCS updates/fixes kselftest/arm64: Check for -EPERM not -EBUSY in the locking test arm64: gcs: Return -EPERM not -EBUSY for prctl() locking failures List of files: /linux/drivers/resctrl/mpam_fb.c

5415b256badbe1681183e85f42462fa01cf09c83 - Merge tag 'mpam/for-next/v7.4_v2' of https://git.kernel.org/pub/scm/linux/kernel/git/morse/linux into for-next/mpam

Fri, 02 Oct 2026 19:58:45 +0200

Merge tag 'mpam/for-next/v7.4_v2' of https://git.kernel.org/pub/scm/linux/kernel/git/morse/linux into for-next/mpam - Fix a list of theoretical issues with the driver. - Add mailing list and a missing file to MAINTAINERS. - Add support for a firmware-backed MPAM interface.* tag 'mpam/for-next/v7.4_v2' of https://git.kernel.org/pub/scm/linux/kernel/git/morse/linux: (27 commits) arm_mpam: detect and enable MPAM-Fb PCC support arm_mpam: change MPAM-Fb error IRQ to use a threaded IRQ handler arm_mpam: add MPAM-Fb MSC firmware access support arm_mpam: prepare mon_sel locking for MPAM-Fb arm_mpam: propagate MSC access errors in mpam_reset_class_locked() arm_mpam: propagate MSC access errors for interrupt control arm_mpam: propagate MSC access errors for mpam_reprogram_ris_partid() arm_mpam: propagate MSC access errors for state saving function arm_mpam: propagate MSC access errors for __ris_msmon_read() arm_mpam: propagate MSC access errors for msmon helpers arm_mpam: propagate MSC access errors for MBWU counters arm_mpam: propagate MSC access errors for hw_probe functions arm_mpam: let low level MSC accessors return an error MAINTAINERS: Use linux-arm-kernel list for the MPAM driver MAINTAINERS: Add mpam.rst to the MPAM DRIVER entry arm_mpam: resctrl: Don't stop early when tearing down a class arm_mpam: Switch to kvzmalloc_objs() for allocation of component cfg arm_mpam: Don't loop forever if there is the maximum possible amount of PARTIDs arm_mpam: resctrl: Make read_mon_cdp_safe() self consistent arm_mpam: resctrl: Correct check that existing class is L3 ... List of files: /linux/drivers/resctrl/mpam_fb.c

cb351e3f304b260fc2f11cca5ed819fc9ac7c46d - arm_mpam: detect and enable MPAM-Fb PCC support

Fri, 02 Oct 2026 18:11:28 +0200

arm_mpam: detect and enable MPAM-Fb PCC supportThe Arm MPAM-Fb specification [1] describes a protocol to access MSCregisters through a firmware interface. This requires a shared memoryregion to hold the message, and a mailbox to trigger the access.For ACPI this is wrapped as a PCC channel, described using existingACPI abstractions.Add code to parse those PCC table descriptions associated with an MSC,and store the parsed information in the MSC struct.There can be multiple PCC channels, and each channel can serve multipleMSCs, so we need to keep track of the channel usage, using a list anda refcount.This will be used by the MPAM-Fb access wrapper code.[1] https://developer.arm.com/documentation/den0144/latestSigned-off-by: Andre Przywara Tested-by: Ritwick Sharma # on Arm AGI CPUReviewed-by: Jonathan Cameron Tested-by: Srivathsa L Rao Reviewed-by: Srivathsa L Rao Reviewed-by: Gavin Shan Reviewed-by: Ben Horgan Signed-off-by: James Morse List of files: /linux/drivers/resctrl/mpam_fb.c

0ef7c5eb77c6cf57582bda2b96a845bdd9e8c9d2 - arm_mpam: add MPAM-Fb MSC firmware access support

Thu, 01 Oct 2026 17:34:36 +0200

arm_mpam: add MPAM-Fb MSC firmware access supportThe Arm MPAM Firmware-backed (Fb) Profile document[1] describes analternative way of accessing the "Memory System Components" (MSC) in anMPAM enabled system.Normally the MSCs are MMIO mapped, but in some implementations thismight not be possible (MSC located outside of the local socket, MSCmapped secure-only) or desirable (direct MMIO access too slow or needsto be mediated through a control processor). MPAM-fb standardises aprotocol to abstract MSC accesses, building on the SCMI protocol.Add functions that do an MSC read or write access by redirecting therequest through a firmware interface. For now this done via an ACPIPCC shared memory and mailbox combination.Since the protocol used is only a small subset of the full SCMI spec,and the SCMI protocol has no full ACPI support anyway, open-code the(simple) SCMI message generation, for just the fields we need.[1] https://developer.arm.com/documentation/den0144/latestSigned-off-by: Andre Przywara Reviewed-by: Jonathan Cameron Tested-by: Ritwick Sharma # on Arm AGI CPUReviewed-by: Gavin Shan Reviewed-by: Srivathsa L Rao Reviewed-by: Ben Horgan Signed-off-by: James Morse List of files: /linux/drivers/resctrl/mpam_fb.c