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2 daysMerge tag 'docs-6.17' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "It has been a relatively busy cycle for docs, especially the build system: - The Perl kernel-doc script was added to 2.3.52pre1 just after the turn of the millennium. Over the following 25 years, it accumulated a vast amount of cruft, all in a language few people want to deal with anymore. Mauro's Python replacement in 6.16 faithfully reproduced all of the cruft in the hope of avoiding regressions. Now that we have a more reasonable code base, though, we can work on cleaning it up; many of the changes this time around are toward that end. - A reorganization of the ext4 docs into the usual TOC format. - Various Chinese translations and updates. - A new script from Mauro to help with docs-build testing. - A new document for linked lists - A sweep through MAINTAINERS fixing broken GitHub git:// repository links. ...and lots of fixes and updates" * tag 'docs-6.17' of git://git.lwn.net/linux: (147 commits) scripts: add origin commit identification based on specific patterns sphinx: kernel_abi: fix performance regression with O=<dir> Documentation: core-api: entry: Replace deprecated KVM entry/exit functions docs: fault-injection: drop reference to md-faulty docs: document linked lists scripts: kdoc: make it backward-compatible with Python 3.7 docs: kernel-doc: emit warnings for ancient versions of Python Documentation/rtla: Describe exit status Documentation/rtla: Add include common_appendix.rst docs: kernel: Clarify printk_ratelimit_burst reset behavior Documentation: ioctl-number: Don't repeat macro names Documentation: ioctl-number: Shorten macros table Documentation: ioctl-number: Correct full path to papr-physical-attestation.h Documentation: ioctl-number: Extend "Include File" column width Documentation: ioctl-number: Fix linuxppc-dev mailto link overlayfs.rst: fix typos docs: kdoc: emit a warning for ancient versions of Python docs: kdoc: clean up check_sections() docs: kdoc: directly access the always-there KdocItem fields docs: kdoc: straighten up dump_declaration() ...
3 daysMerge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "ARM: - Host driver for GICv5, the next generation interrupt controller for arm64, including support for interrupt routing, MSIs, interrupt translation and wired interrupts - Use FEAT_GCIE_LEGACY on GICv5 systems to virtualize GICv3 VMs on GICv5 hardware, leveraging the legacy VGIC interface - Userspace control of the 'nASSGIcap' GICv3 feature, allowing userspace to disable support for SGIs w/o an active state on hardware that previously advertised it unconditionally - Map supporting endpoints with cacheable memory attributes on systems with FEAT_S2FWB and DIC where KVM no longer needs to perform cache maintenance on the address range - Nested support for FEAT_RAS and FEAT_DoubleFault2, allowing the guest hypervisor to inject external aborts into an L2 VM and take traps of masked external aborts to the hypervisor - Convert more system register sanitization to the config-driven implementation - Fixes to the visibility of EL2 registers, namely making VGICv3 system registers accessible through the VGIC device instead of the ONE_REG vCPU ioctls - Various cleanups and minor fixes LoongArch: - Add stat information for in-kernel irqchip - Add tracepoints for CPUCFG and CSR emulation exits - Enhance in-kernel irqchip emulation - Various cleanups RISC-V: - Enable ring-based dirty memory tracking - Improve perf kvm stat to report interrupt events - Delegate illegal instruction trap to VS-mode - MMU improvements related to upcoming nested virtualization s390x - Fixes x86: - Add CONFIG_KVM_IOAPIC for x86 to allow disabling support for I/O APIC, PIC, and PIT emulation at compile time - Share device posted IRQ code between SVM and VMX and harden it against bugs and runtime errors - Use vcpu_idx, not vcpu_id, for GA log tag/metadata, to make lookups O(1) instead of O(n) - For MMIO stale data mitigation, track whether or not a vCPU has access to (host) MMIO based on whether the page tables have MMIO pfns mapped; using VFIO is prone to false negatives - Rework the MSR interception code so that the SVM and VMX APIs are more or less identical - Recalculate all MSR intercepts from scratch on MSR filter changes, instead of maintaining shadow bitmaps - Advertise support for LKGS (Load Kernel GS base), a new instruction that's loosely related to FRED, but is supported and enumerated independently - Fix a user-triggerable WARN that syzkaller found by setting the vCPU in INIT_RECEIVED state (aka wait-for-SIPI), and then putting the vCPU into VMX Root Mode (post-VMXON). Trying to detect every possible path leading to architecturally forbidden states is hard and even risks breaking userspace (if it goes from valid to valid state but passes through invalid states), so just wait until KVM_RUN to detect that the vCPU state isn't allowed - Add KVM_X86_DISABLE_EXITS_APERFMPERF to allow disabling interception of APERF/MPERF reads, so that a "properly" configured VM can access APERF/MPERF. This has many caveats (APERF/MPERF cannot be zeroed on vCPU creation or saved/restored on suspend and resume, or preserved over thread migration let alone VM migration) but can be useful whenever you're interested in letting Linux guests see the effective physical CPU frequency in /proc/cpuinfo - Reject KVM_SET_TSC_KHZ for vm file descriptors if vCPUs have been created, as there's no known use case for changing the default frequency for other VM types and it goes counter to the very reason why the ioctl was added to the vm file descriptor. And also, there would be no way to make it work for confidential VMs with a "secure" TSC, so kill two birds with one stone - Dynamically allocation the shadow MMU's hashed page list, and defer allocating the hashed list until it's actually needed (the TDP MMU doesn't use the list) - Extract many of KVM's helpers for accessing architectural local APIC state to common x86 so that they can be shared by guest-side code for Secure AVIC - Various cleanups and fixes x86 (Intel): - Preserve the host's DEBUGCTL.FREEZE_IN_SMM when running the guest. Failure to honor FREEZE_IN_SMM can leak host state into guests - Explicitly check vmcs12.GUEST_DEBUGCTL on nested VM-Enter to prevent L1 from running L2 with features that KVM doesn't support, e.g. BTF x86 (AMD): - WARN and reject loading kvm-amd.ko instead of panicking the kernel if the nested SVM MSRPM offsets tracker can't handle an MSR (which is pretty much a static condition and therefore should never happen, but still) - Fix a variety of flaws and bugs in the AVIC device posted IRQ code - Inhibit AVIC if a vCPU's ID is too big (relative to what hardware supports) instead of rejecting vCPU creation - Extend enable_ipiv module param support to SVM, by simply leaving IsRunning clear in the vCPU's physical ID table entry - Disable IPI virtualization, via enable_ipiv, if the CPU is affected by erratum #1235, to allow (safely) enabling AVIC on such CPUs - Request GA Log interrupts if and only if the target vCPU is blocking, i.e. only if KVM needs a notification in order to wake the vCPU - Intercept SPEC_CTRL on AMD if the MSR shouldn't exist according to the vCPU's CPUID model - Accept any SNP policy that is accepted by the firmware with respect to SMT and single-socket restrictions. An incompatible policy doesn't put the kernel at risk in any way, so there's no reason for KVM to care - Drop a superfluous WBINVD (on all CPUs!) when destroying a VM and use WBNOINVD instead of WBINVD when possible for SEV cache maintenance - When reclaiming memory from an SEV guest, only do cache flushes on CPUs that have ever run a vCPU for the guest, i.e. don't flush the caches for CPUs that can't possibly have cache lines with dirty, encrypted data Generic: - Rework irqbypass to track/match producers and consumers via an xarray instead of a linked list. Using a linked list leads to O(n^2) insertion times, which is hugely problematic for use cases that create large numbers of VMs. Such use cases typically don't actually use irqbypass, but eliminating the pointless registration is a future problem to solve as it likely requires new uAPI - Track irqbypass's "token" as "struct eventfd_ctx *" instead of a "void *", to avoid making a simple concept unnecessarily difficult to understand - Decouple device posted IRQs from VFIO device assignment, as binding a VM to a VFIO group is not a requirement for enabling device posted IRQs - Clean up and document/comment the irqfd assignment code - Disallow binding multiple irqfds to an eventfd with a priority waiter, i.e. ensure an eventfd is bound to at most one irqfd through the entire host, and add a selftest to verify eventfd:irqfd bindings are globally unique - Add a tracepoint for KVM_SET_MEMORY_ATTRIBUTES to help debug issues related to private <=> shared memory conversions - Drop guest_memfd's .getattr() implementation as the VFS layer will call generic_fillattr() if inode_operations.getattr is NULL - Fix issues with dirty ring harvesting where KVM doesn't bound the processing of entries in any way, which allows userspace to keep KVM in a tight loop indefinitely - Kill off kvm_arch_{start,end}_assignment() and x86's associated tracking, now that KVM no longer uses assigned_device_count as a heuristic for either irqbypass usage or MDS mitigation Selftests: - Fix a comment typo - Verify KVM is loaded when getting any KVM module param so that attempting to run a selftest without kvm.ko loaded results in a SKIP message about KVM not being loaded/enabled (versus some random parameter not existing) - Skip tests that hit EACCES when attempting to access a file, and print a "Root required?" help message. In most cases, the test just needs to be run with elevated permissions" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (340 commits) Documentation: KVM: Use unordered list for pre-init VGIC registers RISC-V: KVM: Avoid re-acquiring memslot in kvm_riscv_gstage_map() RISC-V: KVM: Use find_vma_intersection() to search for intersecting VMAs RISC-V: perf/kvm: Add reporting of interrupt events RISC-V: KVM: Enable ring-based dirty memory tracking RISC-V: KVM: Fix inclusion of Smnpm in the guest ISA bitmap RISC-V: KVM: Delegate illegal instruction fault to VS mode RISC-V: KVM: Pass VMID as parameter to kvm_riscv_hfence_xyz() APIs RISC-V: KVM: Factor-out g-stage page table management RISC-V: KVM: Add vmid field to struct kvm_riscv_hfence RISC-V: KVM: Introduce struct kvm_gstage_mapping RISC-V: KVM: Factor-out MMU related declarations into separate headers RISC-V: KVM: Use ncsr_xyz() in kvm_riscv_vcpu_trap_redirect() RISC-V: KVM: Implement kvm_arch_flush_remote_tlbs_range() RISC-V: KVM: Don't flush TLB when PTE is unchanged RISC-V: KVM: Replace KVM_REQ_HFENCE_GVMA_VMID_ALL with KVM_REQ_TLB_FLUSH RISC-V: KVM: Rename and move kvm_riscv_local_tlb_sanitize() RISC-V: KVM: Drop the return value of kvm_riscv_vcpu_aia_init() RISC-V: KVM: Check kvm_riscv_vcpu_alloc_vector_context() return value KVM: arm64: selftests: Add FEAT_RAS EL2 registers to get-reg-list ...
3 daysMerge tag 'net-next-6.17' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "Core & protocols: - Wrap datapath globals into net_aligned_data, to avoid false sharing - Preserve MSG_ZEROCOPY in forwarding (e.g. out of a container) - Add SO_INQ and SCM_INQ support to AF_UNIX - Add SIOCINQ support to AF_VSOCK - Add TCP_MAXSEG sockopt to MPTCP - Add IPv6 force_forwarding sysctl to enable forwarding per interface - Make TCP validation of whether packet fully fits in the receive window and the rcv_buf more strict. With increased use of HW aggregation a single "packet" can be multiple 100s of kB - Add MSG_MORE flag to optimize large TCP transmissions via sockmap, improves latency up to 33% for sockmap users - Convert TCP send queue handling from tasklet to BH workque - Improve BPF iteration over TCP sockets to see each socket exactly once - Remove obsolete and unused TCP RFC3517/RFC6675 loss recovery code - Support enabling kernel threads for NAPI processing on per-NAPI instance basis rather than a whole device. Fully stop the kernel NAPI thread when threaded NAPI gets disabled. Previously thread would stick around until ifdown due to tricky synchronization - Allow multicast routing to take effect on locally-generated packets - Add output interface argument for End.X in segment routing - MCTP: add support for gateway routing, improve bind() handling - Don't require rtnl_lock when fetching an IPv6 neighbor over Netlink - Add a new neighbor flag ("extern_valid"), which cedes refresh responsibilities to userspace. This is needed for EVPN multi-homing where a neighbor entry for a multi-homed host needs to be synced across all the VTEPs among which the host is multi-homed - Support NUD_PERMANENT for proxy neighbor entries - Add a new queuing discipline for IETF RFC9332 DualQ Coupled AQM - Add sequence numbers to netconsole messages. Unregister netconsole's console when all net targets are removed. Code refactoring. Add a number of selftests - Align IPSec inbound SA lookup to RFC 4301. Only SPI and protocol should be used for an inbound SA lookup - Support inspecting ref_tracker state via DebugFS - Don't force bonding advertisement frames tx to ~333 ms boundaries. Add broadcast_neighbor option to send ARP/ND on all bonded links - Allow providing upcall pid for the 'execute' command in openvswitch - Remove DCCP support from Netfilter's conntrack - Disallow multiple packet duplications in the queuing layer - Prevent use of deprecated iptables code on PREEMPT_RT Driver API: - Support RSS and hashing configuration over ethtool Netlink - Add dedicated ethtool callbacks for getting and setting hashing fields - Add support for power budget evaluation strategy in PSE / Power-over-Ethernet. Generate Netlink events for overcurrent etc - Support DPLL phase offset monitoring across all device inputs. Support providing clock reference and SYNC over separate DPLL inputs - Support traffic classes in devlink rate API for bandwidth management - Remove rtnl_lock dependency from UDP tunnel port configuration Device drivers: - Add a new Broadcom driver for 800G Ethernet (bnge) - Add a standalone driver for Microchip ZL3073x DPLL - Remove IBM's NETIUCV device driver - Ethernet high-speed NICs: - Broadcom (bnxt): - support zero-copy Tx of DMABUF memory - take page size into account for page pool recycling rings - Intel (100G, ice, idpf): - idpf: XDP and AF_XDP support preparations - idpf: add flow steering - add link_down_events statistic - clean up the TSPLL code - preparations for live VM migration - nVidia/Mellanox: - support zero-copy Rx/Tx interfaces (DMABUF and io_uring) - optimize context memory usage for matchers - expose serial numbers in devlink info - support PCIe congestion metrics - Meta (fbnic): - add 25G, 50G, and 100G link modes to phylink - support dumping FW logs - Marvell/Cavium: - support for CN20K generation of the Octeon chips - Amazon: - add HW clock (without timestamping, just hypervisor time access) - Ethernet virtual: - VirtIO net: - support segmentation of UDP-tunnel-encapsulated packets - Google (gve): - support packet timestamping and clock synchronization - Microsoft vNIC: - add handler for device-originated servicing events - allow dynamic MSI-X vector allocation - support Tx bandwidth clamping - Ethernet NICs consumer, and embedded: - AMD: - amd-xgbe: hardware timestamping and PTP clock support - Broadcom integrated MACs (bcmgenet, bcmasp): - use napi_complete_done() return value to support NAPI polling - add support for re-starting auto-negotiation - Broadcom switches (b53): - support BCM5325 switches - add bcm63xx EPHY power control - Synopsys (stmmac): - lots of code refactoring and cleanups - TI: - icssg-prueth: read firmware-names from device tree - icssg: PRP offload support - Microchip: - lan78xx: convert to PHYLINK for improved PHY and MAC management - ksz: add KSZ8463 switch support - Intel: - support similar queue priority scheme in multi-queue and time-sensitive networking (taprio) - support packet pre-emption in both - RealTek (r8169): - enable EEE at 5Gbps on RTL8126 - Airoha: - add PPPoE offload support - MDIO bus controller for Airoha AN7583 - Ethernet PHYs: - support for the IPQ5018 internal GE PHY - micrel KSZ9477 switch-integrated PHYs: - add MDI/MDI-X control support - add RX error counters - add cable test support - add Signal Quality Indicator (SQI) reporting - dp83tg720: improve reset handling and reduce link recovery time - support bcm54811 (and its MII-Lite interface type) - air_en8811h: support resume/suspend - support PHY counters for QCA807x and QCA808x - support WoL for QCA807x - CAN drivers: - rcar_canfd: support for Transceiver Delay Compensation - kvaser: report FW versions via devlink dev info - WiFi: - extended regulatory info support (6 GHz) - add statistics and beacon monitor for Multi-Link Operation (MLO) - support S1G aggregation, improve S1G support - add Radio Measurement action fields - support per-radio RTS threshold - some work around how FIPS affects wifi, which was wrong (RC4 is used by TKIP, not only WEP) - improvements for unsolicited probe response handling - WiFi drivers: - RealTek (rtw88): - IBSS mode for SDIO devices - RealTek (rtw89): - BT coexistence for MLO/WiFi7 - concurrent station + P2P support - support for USB devices RTL8851BU/RTL8852BU - Intel (iwlwifi): - use embedded PNVM in (to be released) FW images to fix compatibility issues - many cleanups (unused FW APIs, PCIe code, WoWLAN) - some FIPS interoperability - MediaTek (mt76): - firmware recovery improvements - more MLO work - Qualcomm/Atheros (ath12k): - fix scan on multi-radio devices - more EHT/Wi-Fi 7 features - encapsulation/decapsulation offload - Broadcom (brcm80211): - support SDIO 43751 device - Bluetooth: - hci_event: add support for handling LE BIG Sync Lost event - ISO: add socket option to report packet seqnum via CMSG - ISO: support SCM_TIMESTAMPING for ISO TS - Bluetooth drivers: - intel_pcie: support Function Level Reset - nxpuart: add support for 4M baudrate - nxpuart: implement powerup sequence, reset, FW dump, and FW loading" * tag 'net-next-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1742 commits) dpll: zl3073x: Fix build failure selftests: bpf: fix legacy netfilter options ipv6: annotate data-races around rt->fib6_nsiblings ipv6: fix possible infinite loop in fib6_info_uses_dev() ipv6: prevent infinite loop in rt6_nlmsg_size() ipv6: add a retry logic in net6_rt_notify() vrf: Drop existing dst reference in vrf_ip6_input_dst net/sched: taprio: align entry index attr validation with mqprio net: fsl_pq_mdio: use dev_err_probe selftests: rtnetlink.sh: remove esp4_offload after test vsock: remove unnecessary null check in vsock_getname() igb: xsk: solve negative overflow of nb_pkts in zerocopy mode stmmac: xsk: fix negative overflow of budget in zerocopy mode dt-bindings: ieee802154: Convert at86rf230.txt yaml format net: dsa: microchip: Disable PTP function of KSZ8463 net: dsa: microchip: Setup fiber ports for KSZ8463 net: dsa: microchip: Write switch MAC address differently for KSZ8463 net: dsa: microchip: Use different registers for KSZ8463 net: dsa: microchip: Add KSZ8463 switch support to KSZ DSA driver dt-bindings: net: dsa: microchip: Add KSZ8463 switch support ...
4 daysMerge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: "A quick summary: perf support for Branch Record Buffer Extensions (BRBE), typical PMU hardware updates, small additions to MTE for store-only tag checking and exposing non-address bits to signal handlers, HAVE_LIVEPATCH enabled on arm64, VMAP_STACK forced on. There is also a TLBI optimisation on hardware that does not require break-before-make when changing the user PTEs between contiguous and non-contiguous. More details: Perf and PMU updates: - Add support for new (v3) Hisilicon SLLC and DDRC PMUs - Add support for Arm-NI PMU integrations that share interrupts between clock domains within a given instance - Allow SPE to be configured with a lower sample period than the minimum recommendation advertised by PMSIDR_EL1.Interval - Add suppport for Arm's "Branch Record Buffer Extension" (BRBE) - Adjust the perf watchdog period according to cpu frequency changes - Minor driver fixes and cleanups Hardware features: - Support for MTE store-only checking (FEAT_MTE_STORE_ONLY) - Support for reporting the non-address bits during a synchronous MTE tag check fault (FEAT_MTE_TAGGED_FAR) - Optimise the TLBI when folding/unfolding contiguous PTEs on hardware with FEAT_BBM (break-before-make) level 2 and no TLB conflict aborts Software features: - Enable HAVE_LIVEPATCH after implementing arch_stack_walk_reliable() and using the text-poke API for late module relocations - Force VMAP_STACK always on and change arm64_efi_rt_init() to use arch_alloc_vmap_stack() in order to avoid KASAN false positives ACPI: - Improve SPCR handling and messaging on systems lacking an SPCR table Debug: - Simplify the debug exception entry path - Drop redundant DBG_MDSCR_* macros Kselftests: - Cleanups and improvements for SME, SVE and FPSIMD tests Miscellaneous: - Optimise loop to reduce redundant operations in contpte_ptep_get() - Remove ISB when resetting POR_EL0 during signal handling - Mark the kernel as tainted on SEA and SError panic - Remove redundant gcs_free() call" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (93 commits) arm64/gcs: task_gcs_el0_enable() should use passed task arm64: Kconfig: Keep selects somewhat alphabetically ordered arm64: signal: Remove ISB when resetting POR_EL0 kselftest/arm64: Handle attempts to disable SM on SME only systems kselftest/arm64: Fix SVE write data generation for SME only systems kselftest/arm64: Test SME on SME only systems in fp-ptrace kselftest/arm64: Test FPSIMD format data writes via NT_ARM_SVE in fp-ptrace kselftest/arm64: Allow sve-ptrace to run on SME only systems arm64/mm: Drop redundant addr increment in set_huge_pte_at() kselftest/arm4: Provide local defines for AT_HWCAP3 arm64: Mark kernel as tainted on SAE and SError panic arm64/gcs: Don't call gcs_free() when releasing task_struct drivers/perf: hisi: Support PMUs with no interrupt drivers/perf: hisi: Relax the event number check of v2 PMUs drivers/perf: hisi: Add support for HiSilicon SLLC v3 PMU driver drivers/perf: hisi: Use ACPI driver_data to retrieve SLLC PMU information drivers/perf: hisi: Add support for HiSilicon DDRC v3 PMU driver drivers/perf: hisi: Simplify the probe process for each DDRC version perf/arm-ni: Support sharing IRQs within an NI instance perf/arm-ni: Consolidate CPU affinity handling ...
4 daysMerge tag 'x86-platform-2025-07-29' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 platform updates from Ingo Molnar: "This adds support for the AMD hardware feedback interface (HFI), by Perry Yuan" * tag 'x86-platform-2025-07-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/itmt: Add debugfs file to show core priorities platform/x86/amd: hfi: Add debugfs support platform/x86/amd: hfi: Set ITMT priority from ranking data cpufreq/amd-pstate: Disable preferred cores on designs with workload classification x86/process: Clear hardware feedback history for AMD processors platform/x86: hfi: Add power management callback platform/x86: hfi: Add online and offline callback support platform/x86: hfi: Init per-cpu scores for each class platform/x86: hfi: Parse CPU core ranking data from shared memory platform/x86: hfi: Introduce AMD Hardware Feedback Interface Driver x86/msr-index: Add AMD workload classification MSRs MAINTAINERS: Add maintainer entry for AMD Hardware Feedback Driver Documentation/x86: Add AMD Hardware Feedback Interface documentation
4 daysMerge tag 'kvmarm-6.17' of ↵Paolo Bonzini
https://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 changes for 6.17, round #1 - Host driver for GICv5, the next generation interrupt controller for arm64, including support for interrupt routing, MSIs, interrupt translation and wired interrupts. - Use FEAT_GCIE_LEGACY on GICv5 systems to virtualize GICv3 VMs on GICv5 hardware, leveraging the legacy VGIC interface. - Userspace control of the 'nASSGIcap' GICv3 feature, allowing userspace to disable support for SGIs w/o an active state on hardware that previously advertised it unconditionally. - Map supporting endpoints with cacheable memory attributes on systems with FEAT_S2FWB and DIC where KVM no longer needs to perform cache maintenance on the address range. - Nested support for FEAT_RAS and FEAT_DoubleFault2, allowing the guest hypervisor to inject external aborts into an L2 VM and take traps of masked external aborts to the hypervisor. - Convert more system register sanitization to the config-driven implementation. - Fixes to the visibility of EL2 registers, namely making VGICv3 system registers accessible through the VGIC device instead of the ONE_REG vCPU ioctls. - Various cleanups and minor fixes.
5 daysMerge tag 'hardening-v6.17-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull hardening updates from Kees Cook: - Introduce and start using TRAILING_OVERLAP() helper for fixing embedded flex array instances (Gustavo A. R. Silva) - mux: Convert mux_control_ops to a flex array member in mux_chip (Thorsten Blum) - string: Group str_has_prefix() and strstarts() (Andy Shevchenko) - Remove KCOV instrumentation from __init and __head (Ritesh Harjani, Kees Cook) - Refactor and rename stackleak feature to support Clang - Add KUnit test for seq_buf API - Fix KUnit fortify test under LTO * tag 'hardening-v6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (22 commits) sched/task_stack: Add missing const qualifier to end_of_stack() kstack_erase: Support Clang stack depth tracking kstack_erase: Add -mgeneral-regs-only to silence Clang warnings init.h: Disable sanitizer coverage for __init and __head kstack_erase: Disable kstack_erase for all of arm compressed boot code x86: Handle KCOV __init vs inline mismatches arm64: Handle KCOV __init vs inline mismatches s390: Handle KCOV __init vs inline mismatches arm: Handle KCOV __init vs inline mismatches mips: Handle KCOV __init vs inline mismatch powerpc/mm/book3s64: Move kfence and debug_pagealloc related calls to __init section configs/hardening: Enable CONFIG_INIT_ON_FREE_DEFAULT_ON configs/hardening: Enable CONFIG_KSTACK_ERASE stackleak: Split KSTACK_ERASE_CFLAGS from GCC_PLUGINS_CFLAGS stackleak: Rename stackleak_track_stack to __sanitizer_cov_stack_depth stackleak: Rename STACKLEAK to KSTACK_ERASE seq_buf: Introduce KUnit tests string: Group str_has_prefix() and strstarts() kunit/fortify: Add back "volatile" for sizeof() constants acpi: nfit: intel: avoid multiple -Wflex-array-member-not-at-end warnings ...
9 daysMerge branch 'for-next/feat_mte_store_only' into for-next/coreCatalin Marinas
* for-next/feat_mte_store_only: : MTE feature to restrict tag checking to store only operations kselftest/arm64/mte: Add MTE_STORE_ONLY testcases kselftest/arm64/mte: Preparation for mte store only test kselftest/arm64/abi: Add MTE_STORE_ONLY feature hwcap test KVM: arm64: Expose MTE_STORE_ONLY feature to guest arm64/hwcaps: Add MTE_STORE_ONLY hwcaps arm64/kernel: Support store-only mte tag check prctl: Introduce PR_MTE_STORE_ONLY arm64/cpufeature: Add MTE_STORE_ONLY feature
9 daysMerge branches 'for-next/livepatch', 'for-next/user-contig-bbml2', ↵Catalin Marinas
'for-next/misc', 'for-next/acpi', 'for-next/debug-entry', 'for-next/feat_mte_tagged_far', 'for-next/kselftest', 'for-next/mdscr-cleanup' and 'for-next/vmap-stack', remote-tracking branch 'arm64/for-next/perf' into for-next/core * arm64/for-next/perf: (23 commits) drivers/perf: hisi: Support PMUs with no interrupt drivers/perf: hisi: Relax the event number check of v2 PMUs drivers/perf: hisi: Add support for HiSilicon SLLC v3 PMU driver drivers/perf: hisi: Use ACPI driver_data to retrieve SLLC PMU information drivers/perf: hisi: Add support for HiSilicon DDRC v3 PMU driver drivers/perf: hisi: Simplify the probe process for each DDRC version perf/arm-ni: Support sharing IRQs within an NI instance perf/arm-ni: Consolidate CPU affinity handling perf/cxlpmu: Fix typos in cxl_pmu.c comments and documentation perf/cxlpmu: Remove unintended newline from IRQ name format string perf/cxlpmu: Fix devm_kcalloc() argument order in cxl_pmu_probe() perf: arm_spe: Relax period restriction perf: arm_pmuv3: Add support for the Branch Record Buffer Extension (BRBE) KVM: arm64: nvhe: Disable branch generation in nVHE guests arm64: Handle BRBE booting requirements arm64/sysreg: Add BRBE registers and fields perf/arm: Add missing .suppress_bind_attrs perf/arm-cmn: Reduce stack usage during discovery perf: imx9_perf: make the read-only array mask static const perf/arm-cmn: Broaden module description for wider interconnect support ... * for-next/livepatch: : Support for HAVE_LIVEPATCH on arm64 arm64: Kconfig: Keep selects somewhat alphabetically ordered arm64: Implement HAVE_LIVEPATCH arm64: stacktrace: Implement arch_stack_walk_reliable() arm64: stacktrace: Check kretprobe_find_ret_addr() return value arm64/module: Use text-poke API for late relocations. * for-next/user-contig-bbml2: : Optimise the TLBI when folding/unfolding contigous PTEs on hardware with BBML2 and no TLB conflict aborts arm64/mm: Elide tlbi in contpte_convert() under BBML2 iommu/arm: Add BBM Level 2 smmu feature arm64: Add BBM Level 2 cpu feature arm64: cpufeature: Introduce MATCH_ALL_EARLY_CPUS capability type * for-next/misc: : Miscellaneous arm64 patches arm64/gcs: task_gcs_el0_enable() should use passed task arm64: signal: Remove ISB when resetting POR_EL0 arm64/mm: Drop redundant addr increment in set_huge_pte_at() arm64: Mark kernel as tainted on SAE and SError panic arm64/gcs: Don't call gcs_free() when releasing task_struct arm64: fix unnecessary rebuilding when CONFIG_DEBUG_EFI=y arm64/mm: Optimize loop to reduce redundant operations of contpte_ptep_get arm64: pi: use 'targets' instead of extra-y in Makefile * for-next/acpi: : Various ACPI arm64 changes ACPI: Suppress misleading SPCR console message when SPCR table is absent ACPI: Return -ENODEV from acpi_parse_spcr() when SPCR support is disabled * for-next/debug-entry: : Simplify the debug exception entry path arm64: debug: remove debug exception registration infrastructure arm64: debug: split bkpt32 exception entry arm64: debug: split brk64 exception entry arm64: debug: split hardware watchpoint exception entry arm64: debug: split single stepping exception entry arm64: debug: refactor reinstall_suspended_bps() arm64: debug: split hardware breakpoint exception entry arm64: entry: Add entry and exit functions for debug exceptions arm64: debug: remove break/step handler registration infrastructure arm64: debug: call step handlers statically arm64: debug: call software breakpoint handlers statically arm64: refactor aarch32_break_handler() arm64: debug: clean up single_step_handler logic * for-next/feat_mte_tagged_far: : Support for reporting the non-address bits during a synchronous MTE tag check fault kselftest/arm64/mte: Add mtefar tests on check_mmap_options kselftest/arm64/mte: Refactor check_mmap_option test kselftest/arm64/mte: Add verification for address tag in signal handler kselftest/arm64/mte: Add address tag related macro and function kselftest/arm64/mte: Check MTE_FAR feature is supported kselftest/arm64/mte: Register mte signal handler with SA_EXPOSE_TAGBITS kselftest/arm64: Add MTE_FAR hwcap test KVM: arm64: Expose FEAT_MTE_TAGGED_FAR feature to guest arm64: Report address tag when FEAT_MTE_TAGGED_FAR is supported arm64/cpufeature: Add FEAT_MTE_TAGGED_FAR feature * for-next/kselftest: : Kselftest updates for arm64 kselftest/arm64: Handle attempts to disable SM on SME only systems kselftest/arm64: Fix SVE write data generation for SME only systems kselftest/arm64: Test SME on SME only systems in fp-ptrace kselftest/arm64: Test FPSIMD format data writes via NT_ARM_SVE in fp-ptrace kselftest/arm64: Allow sve-ptrace to run on SME only systems kselftest/arm4: Provide local defines for AT_HWCAP3 kselftest/arm64: Specify SVE data when testing VL set in sve-ptrace kselftest/arm64: Fix test for streaming FPSIMD write in sve-ptrace kselftest/arm64: Fix check for setting new VLs in sve-ptrace kselftest/arm64: Convert tpidr2 test to use kselftest.h * for-next/mdscr-cleanup: : Drop redundant DBG_MDSCR_* macros KVM: selftests: Change MDSCR_EL1 register holding variables as uint64_t arm64/debug: Drop redundant DBG_MDSCR_* macros * for-next/vmap-stack: : Force VMAP_STACK on arm64 arm64: remove CONFIG_VMAP_STACK checks from entry code arm64: remove CONFIG_VMAP_STACK checks from SDEI stack handling arm64: remove CONFIG_VMAP_STACK checks from stacktrace overflow logic arm64: remove CONFIG_VMAP_STACK conditionals from traps overflow stack arm64: remove CONFIG_VMAP_STACK conditionals from irq stack setup arm64: Remove CONFIG_VMAP_STACK conditionals from THREAD_SHIFT and THREAD_ALIGN arm64: efi: Remove CONFIG_VMAP_STACK check arm64: Mandate VMAP_STACK arm64: efi: Fix KASAN false positive for EFI runtime stack arm64/ptrace: Fix stack-out-of-bounds read in regs_get_kernel_stack_nth() arm64/gcs: Don't call gcs_free() during flush_gcs() arm64: Restrict pagetable teardown to avoid false warning docs: arm64: Fix ICC_SRE_EL2 register typo in booting.rst
12 daysstackleak: Rename STACKLEAK to KSTACK_ERASEKees Cook
In preparation for adding Clang sanitizer coverage stack depth tracking that can support stack depth callbacks: - Add the new top-level CONFIG_KSTACK_ERASE option which will be implemented either with the stackleak GCC plugin, or with the Clang stack depth callback support. - Rename CONFIG_GCC_PLUGIN_STACKLEAK as needed to CONFIG_KSTACK_ERASE, but keep it for anything specific to the GCC plugin itself. - Rename all exposed "STACKLEAK" names and files to "KSTACK_ERASE" (named for what it does rather than what it protects against), but leave as many of the internals alone as possible to avoid even more churn. While here, also split "prev_lowest_stack" into CONFIG_KSTACK_ERASE_METRICS, since that's the only place it is referenced from. Suggested-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20250717232519.2984886-1-kees@kernel.org Signed-off-by: Kees Cook <kees@kernel.org>
2025-07-16s390/net: Remove NETIUCV device driverNagamani PV
The netiucv driver creates TCP/IP interfaces over IUCV between Linux guests on z/VM and other z/VM entities. Rationale for removal: - NETIUCV connections are only supported for compatibility with earlier versions and not to be used for new network setups, since at least Linux kernel 4.0. - No known active users, use cases, or product dependencies - The driver is no longer relevant for z/VM networking; preferred methods include: * Device pass-through (e.g., OSA, RoCE) * z/VM Virtual Switch (VSWITCH) The IUCV mechanism itself remains supported and is actively used via AF_IUCV, hvc_iucv, and smsg_iucv. Signed-off-by: Nagamani PV <nagamani@linux.ibm.com> Reviewed-by: Alexandra Winter <wintera@linux.ibm.com> Signed-off-by: Alexandra Winter <wintera@linux.ibm.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20250715074210.3999296-1-wintera@linux.ibm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-08docs: arm64: gic-v5: Document booting requirements for GICv5Lorenzo Pieralisi
Document the requirements for booting a kernel on a system implementing a GICv5 interrupt controller. Specifically, other than DT/ACPI providing the required firmware representation, define what traps must be disabled if the kernel is booted at EL1 on a system where EL2 is implemented. Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org> Reviewed-by: Marc Zyngier <maz@kernel.org> Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marc Zyngier <maz@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20250703-gicv5-host-v7-30-12e71f1b3528@kernel.org Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-07-08arm64: Handle BRBE booting requirementsAnshuman Khandual
To use the Branch Record Buffer Extension (BRBE), some configuration is necessary at EL3 and EL2. This patch documents the requirements and adds the initial EL2 setup code, which largely consists of configuring the fine-grained traps and initializing a couple of BRBE control registers. Before this patch, __init_el2_fgt() would initialize HDFGRTR_EL2 and HDFGWTR_EL2 with the same value, relying on the read/write trap controls for a register occupying the same bit position in either register. The 'nBRBIDR' trap control only exists in bit 59 of HDFGRTR_EL2, while bit 59 of HDFGWTR_EL2 is RES0, and so this assumption no longer holds. To handle HDFGRTR_EL2 and HDFGWTR_EL2 having (slightly) different bit layouts, __init_el2_fgt() is changed to accumulate the HDFGRTR_EL2 and HDFGWTR_EL2 control bits separately. While making this change the open-coded value (1 << 62) is replaced with HDFG{R,W}TR_EL2_nPMSNEVFR_EL1_MASK. The BRBCR_EL1 and BRBCR_EL2 registers are unusual and require special initialisation: even though they are subject to E2H renaming, both have an effect regardless of HCR_EL2.TGE, even when running at EL2. So we must initialize BRBCR_EL2 in case we run in nVHE mode. This is handled in __init_el2_brbe() with a comment to explain the situation. Cc: Marc Zyngier <maz@kernel.org> Cc: Oliver Upton <oliver.upton@linux.dev> Reviewed-by: Leo Yan <leo.yan@arm.com> Tested-by: James Clark <james.clark@linaro.org> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> [Mark: rewrite commit message, fix typo in comment] Signed-off-by: Mark Rutland <mark.rutland@arm.com> Co-developed-by: Rob Herring (Arm) <robh@kernel.org> Signed-off-by: Rob Herring (Arm) <robh@kernel.org> tested-by: Adam Young <admiyo@os.amperecomputing.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20250611-arm-brbe-v19-v23-2-e7775563036e@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2025-07-07Merge tag 'tsa_x86_bugs_for_6.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull CPU speculation fixes from Borislav Petkov: "Add the mitigation logic for Transient Scheduler Attacks (TSA) TSA are new aspeculative side channel attacks related to the execution timing of instructions under specific microarchitectural conditions. In some cases, an attacker may be able to use this timing information to infer data from other contexts, resulting in information leakage. Add the usual controls of the mitigation and integrate it into the existing speculation bugs infrastructure in the kernel" * tag 'tsa_x86_bugs_for_6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/process: Move the buffer clearing before MONITOR x86/microcode/AMD: Add TSA microcode SHAs KVM: SVM: Advertise TSA CPUID bits to guests x86/bugs: Add a Transient Scheduler Attacks mitigation x86/bugs: Rename MDS machinery to something more generic
2025-07-07Documentation/x86: Add AMD Hardware Feedback Interface documentationPerry Yuan
Introduce a new documentation file, `amd_hfi.rst`, which delves into the implementation details of the AMD Hardware Feedback Interface and its associated driver, `amd_hfi`. This documentation describes how the driver provides hint to the OS scheduling which depends on the capability of core performance and efficiency ranking data. This documentation describes: * The design of the driver * How the driver provides hints to the OS scheduling * How the driver interfaces with the kernel for efficiency ranking data. Signed-off-by: Perry Yuan <Perry.Yuan@amd.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Reviewed-by: Mario Limonciello <mario.limonciello@amd.com> Acked-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/20250609200518.3616080-2-superm1@kernel.org
2025-07-02arm64/hwcaps: Add MTE_STORE_ONLY hwcapsYeoreum Yun
Since ARMv8.9, FEAT_MTE_STORE_ONLY can be used to restrict raise of tag check fault on store operation only. add MTE_STORE_ONLY hwcaps so that user can use this feature. Signed-off-by: Yeoreum Yun <yeoreum.yun@arm.com> Link: https://lore.kernel.org/r/20250618092957.2069907-5-yeoreum.yun@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2025-07-02arm64: Report address tag when FEAT_MTE_TAGGED_FAR is supportedYeoreum Yun
If FEAT_MTE_TAGGED_FAR (Armv8.9) is supported, bits 63:60 of the fault address are preserved in response to synchronous tag check faults (SEGV_MTESERR). This patch modifies below to support this feature: - Use the original FAR_EL1 value when an MTE tag check fault occurs, if ARM64_MTE_FAR is supported so that not only logical tag (bits 59:56) but also address tag (bits 63:60] being reported too. - Add HWCAP for mtefar to let user know bits 63:60 includes address tag information when when FEAT_MTE_TAGGED_FAR is supported. Applications that require this information should install a signal handler with the SA_EXPOSE_TAGBITS flag. While this introduces a minor ABI change, most applications do not set this flag and therefore will not be affected. Signed-off-by: Yeoreum Yun <yeoreum.yun@arm.com> Link: https://lore.kernel.org/r/20250618084513.1761345-3-yeoreum.yun@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2025-06-16x86/bugs: Rename MDS machinery to something more genericBorislav Petkov (AMD)
It will be used by other x86 mitigations. No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
2025-06-12docs: arm64: Fix ICC_SRE_EL2 register typo in booting.rstLorenzo Pieralisi
Fix trivial ICC_SRE_EL2 register spelling typo in booting.rst. Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Will Deacon <will@kernel.org> CC: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20250610120935.852034-1-lpieralisi@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2025-06-09docs: powerpc: Add htm.rst to table of contentsBrigham Campbell
Fix the following documentation build error, which was introduced when Documentation/arch/powerpc/htm.rst was added to the repository without any reference to the document. Documentation/arch/powerpc/htm.rst: WARNING: document isn't included in any toctree [toc.not_included] Fixes: ab1456c5aa7a ("powerpc/pseries/htmdump: Add documentation for H_HTM debugfs interface") Acked-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Brigham Campbell <me@brighamcampbell.com> Tested-by: Athira Rajeev <atrajeev@linux.ibm.com> Fixes: ab1456c5aa7a63d5 ("powerpc/pseries/htmdump: Add documentation for H_HTM debugfs interface") Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20250528054146.2658537-2-me@brighamcampbell.com
2025-06-06Merge tag 'riscv-for-linus-6.16-mw1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - Support for the FWFT SBI extension, which is part of SBI 3.0 and a dependency for many new SBI and ISA extensions - Support for getrandom() in the VDSO - Support for mseal - Optimized routines for raid6 syndrome and recovery calculations - kexec_file() supports loading Image-formatted kernel binaries - Improvements to the instruction patching framework to allow for atomic instruction patching, along with rules as to how systems need to behave in order to function correctly - Support for a handful of new ISA extensions: Svinval, Zicbop, Zabha, some SiFive vendor extensions - Various fixes and cleanups, including: misaligned access handling, perf symbol mangling, module loading, PUD THPs, and improved uaccess routines * tag 'riscv-for-linus-6.16-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (69 commits) riscv: uaccess: Only restore the CSR_STATUS SUM bit RISC-V: vDSO: Wire up getrandom() vDSO implementation riscv: enable mseal sysmap for RV64 raid6: Add RISC-V SIMD syndrome and recovery calculations riscv: mm: Add support for Svinval extension RISC-V: Documentation: Add enough title underlines to CMODX riscv: Improve Kconfig help for RISCV_ISA_V_PREEMPTIVE MAINTAINERS: Update Atish's email address riscv: uaccess: do not do misaligned accesses in get/put_user() riscv: process: use unsigned int instead of unsigned long for put_user() riscv: make unsafe user copy routines use existing assembly routines riscv: hwprobe: export Zabha extension riscv: Make regs_irqs_disabled() more clear perf symbols: Ignore mapping symbols on riscv RISC-V: Kconfig: Fix help text of CMDLINE_EXTEND riscv: module: Optimize PLT/GOT entry counting riscv: Add support for PUD THP riscv: xchg: Prefetch the destination word for sc.w riscv: Add ARCH_HAS_PREFETCH[W] support with Zicbop riscv: Add support for Zicbop ...
2025-06-05Merge tag 'riscv-mw2-6.16-rc1' of ↵Palmer Dabbelt
ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/alexghiti/linux into for-next riscv patches for 6.16-rc1, part 2 * Performance improvements - Add support for vdso getrandom - Implement raid6 calculations using vectors - Introduce svinval tlb invalidation * Cleanup - A bunch of deduplication of the macros we use for manipulating instructions * Misc - Introduce a kunit test for kprobes - Add support for mseal as riscv fits the requirements (thanks to Lorenzo for making sure of that :)) [Palmer: There was a rebase between part 1 and part 2, so I've had to do some more git surgery here... at least two rounds of surgery...] * alex-pr-2: (866 commits) RISC-V: vDSO: Wire up getrandom() vDSO implementation riscv: enable mseal sysmap for RV64 raid6: Add RISC-V SIMD syndrome and recovery calculations riscv: mm: Add support for Svinval extension riscv: Add kprobes KUnit test riscv: kprobes: Remove duplication of RV_EXTRACT_ITYPE_IMM riscv: kprobes: Remove duplication of RV_EXTRACT_UTYPE_IMM riscv: kprobes: Remove duplication of RV_EXTRACT_RD_REG riscv: kprobes: Remove duplication of RVC_EXTRACT_BTYPE_IMM riscv: kprobes: Remove duplication of RVC_EXTRACT_C2_RS1_REG riscv: kproves: Remove duplication of RVC_EXTRACT_JTYPE_IMM riscv: kprobes: Remove duplication of RV_EXTRACT_BTYPE_IMM riscv: kprobes: Remove duplication of RV_EXTRACT_RS1_REG riscv: kprobes: Remove duplication of RV_EXTRACT_JTYPE_IMM riscv: kprobes: Move branch_funct3 to insn.h riscv: kprobes: Move branch_rs2_idx to insn.h Linux 6.15-rc6 Input: xpad - fix xpad_device sorting Input: xpad - add support for several more controllers Input: xpad - fix Share button on Xbox One controllers ...
2025-06-05RISC-V: Documentation: Add enough title underlines to CMODXPalmer Dabbelt
This reports as a warning in linux-next along the lines of Documentation/arch/riscv/cmodx.rst:14: WARNING: Title underline too short. CMODX in the Kernel Space --------------------- [docutils] Documentation/arch/riscv/cmodx.rst:43: WARNING: Title underline too short. CMODX in the User Space --------------------- [docutils] Documentation/arch/riscv/cmodx.rst:43: WARNING: Title underline too short. CMODX in the User Space --------------------- [docutils] Link: https://lore.kernel.org/all/20250603154544.1602a8b5@canb.auug.org.au/ Fixes: 0e07200b2af6 ("riscv: Documentation: add a description about dynamic ftrace") Reviewed-by: Charlie Jenkins <charlie@rivosinc.com> Link: https://lore.kernel.org/r/20250603172856.49925-1-palmer@dabbelt.com Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
2025-06-05Merge tag 'riscv-mw1-6.16-rc1' of ↵Palmer Dabbelt
ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/alexghiti/linux into for-next riscv patches for 6.16-rc1 * Implement atomic patching support for ftrace which finally allows to get rid of stop_machine(). * Support for kexec_file_load() syscall * Improve module loading time by changing the algorithm that counts the number of plt/got entries in a module. * Zicbop is now used in the kernel to prefetch instructions [Palmer: There's been two rounds of surgery on this one, so as a result it's a bit different than the PR.] * alex-pr: (734 commits) riscv: Improve Kconfig help for RISCV_ISA_V_PREEMPTIVE MAINTAINERS: Update Atish's email address riscv: hwprobe: export Zabha extension riscv: Make regs_irqs_disabled() more clear perf symbols: Ignore mapping symbols on riscv RISC-V: Kconfig: Fix help text of CMDLINE_EXTEND riscv: module: Optimize PLT/GOT entry counting riscv: Add support for PUD THP riscv: xchg: Prefetch the destination word for sc.w riscv: Add ARCH_HAS_PREFETCH[W] support with Zicbop riscv: Add support for Zicbop riscv: Introduce Zicbop instructions riscv/kexec_file: Fix comment in purgatory relocator riscv: kexec_file: Support loading Image binary file riscv: kexec_file: Split the loading of kernel and others riscv: Documentation: add a description about dynamic ftrace riscv: ftrace: support direct call using call_ops riscv: Implement HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS riscv: ftrace: support PREEMPT riscv: add a data fence for CMODX in the kernel mode ... Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
2025-06-05riscv: hwprobe: export Zabha extensionAlexandre Ghiti
Export Zabha through the hwprobe syscall. Reviewed-by: Clément Léger <cleger@rivosinc.com> Link: https://lore.kernel.org/r/20250421141413.394444-1-alexghiti@rivosinc.com Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
2025-06-05riscv: Documentation: add a description about dynamic ftraceAndy Chiu
Add a section in cmodx to describe how dynamic ftrace works on riscv, limitations, and assumptions. Signed-off-by: Andy Chiu <andybnac@gmail.com> Link: https://lore.kernel.org/r/20250407180838.42877-12-andybnac@gmail.com Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
2025-06-01Merge tag 'for-linus' of https://github.com/openrisc/linuxLinus Torvalds
Pull OpenRISC updates from Stafford Horne: "Just a few documentation updates from the community: - Device tree documentation conversion from txt to yaml - Documentation addition to help users getting started with initramfs on OpenRISC * tag 'for-linus' of https://github.com/openrisc/linux: dt-bindings: interrupt-controller: Convert openrisc,ompic to DT schema dt-bindings: interrupt-controller: Convert opencores,or1k-pic to DT schema Documentation:openrisc: Add build instructions with initramfs
2025-05-29Merge tag 'platform-drivers-x86-v6.16-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86 Pull x86 platform drivers updates from Ilpo Järvinen: "The changes are mostly business as usual. Besides pdx86 changes, there are a few power supply changes needed for related pdx86 features, move of oxpec driver from hwmon (oxp-sensors) to pdx86, and one FW version warning to hid-asus. Highlights: - alienware-wmi-wmax: - Add HWMON support - Add ABI and admin-guide documentation - Expose GPIO debug methods through debug FS - Support manual fan control and "custom" thermal profile - amd/hsmp: - Add sysfs files to show HSMP telemetry - Report power readings and limits via hwmon - amd/isp4: Add AMD ISP platform config for OV05C10 - asus-wmi: - Refactor Ally suspend/resume to work better with older FW - hid-asus: check ROG Ally MCU version and warn about old FW versions - dasharo-acpi: - Add driver for Dasharo devices supporting fans and temperatures monitoring - dell-ddv: - Expose the battery health and manufacture date to userspace using power supply extensions - Implement the battery matching algorithm - dell-pc: - Improve error propagation - Use faux device - int3472: - Add delays to avoid GPIO regulator spikes - Add handshake pin support - Make regulator supply name configurable and allow registering more than 1 GPIO regulator - Map mt9m114 powerdown pin to powerenable - intel/pmc: Add separate SSRAM Telemetry driver - intel-uncore-freq: Add attributes to show agent types and die ID - ISST: - Support SST-TF revision 2 (allows more cores per bucket) - Support SST-PP revision 2 (fabric 1 frequencies) - Remove unnecessary SST MSRs restore (the package retains MSRs despite CPU offlining) - mellanox: Add support for SN2201, SN4280, SN5610, and SN5640 - mellanox: mlxbf-pmc: Support additional PMC blocks - oxpec: - Add OneXFly variants - Add support for charge limit, charge thresholds, and turbo LED - Distinguish current X1 variants to avoid unwanted matching to new variants - Follow hwmon conventions - Move from hwmon/oxp-sensors to platform/x86 to match the enlarged scope - power supply: - Add inhibit-charge-awake (needed by oxpec) - Add additional battery health status values ("blown fuse" and "cell imbalance") (needed by dell-ddv) - powerwell-ec: Add driver for Portwell EC supporting GPIO and watchdog - thinkpad-acpi: Support camera shutter switch hotkey - tuxedo: Add virtual LampArray for TUXEDO NB04 devices - tools/power/x86/intel-speed-select: - Support displaying SST-PP revision 2 fields - Skip uncore frequency update on newer generations of CPUs - Miscellaneous cleanups / refactoring / improvements" * tag 'platform-drivers-x86-v6.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86: (112 commits) thermal/drivers/acerhdf: Constify struct thermal_zone_device_ops platform/x86/amd/hsmp: fix building with CONFIG_HWMON=m platform/x86: asus-wmi: fix build without CONFIG_SUSPEND docs: ABI: Fix "aassociated" to "associated" platform/x86: Add AMD ISP platform config for OV05C10 Documentation: admin-guide: pm: Add documentation for die_id platform/x86/intel-uncore-freq: Add attributes to show die_id platform/x86/intel: power-domains: Add interface to get Linux die ID Documentation: admin-guide: pm: Add documentation for agent_types platform/x86/intel-uncore-freq: Add attributes to show agent types platform/x86/tuxedo: Prevent invalid Kconfig state platform/x86: dell-ddv: Expose the battery health to userspace platform/x86: dell-ddv: Expose the battery manufacture date to userspace platform/x86: dell-ddv: Implement the battery matching algorithm power: supply: core: Add additional health status values platform/x86/amd/hsmp: acpi: Add sysfs files to display HSMP telemetry platform/x86/amd/hsmp: Report power via hwmon sensors platform/x86/amd/hsmp: Use a single DRIVER_VERSION for all hsmp modules platform/mellanox: mlxreg-dpu: Fix smatch warnings platform: mellanox: nvsw-sn2200: Fix .items in nvsw_sn2201_busbar_hotplug ...
2025-05-29Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "As far as x86 goes this pull request "only" includes TDX host support. Quotes are appropriate because (at 6k lines and 100+ commits) it is much bigger than the rest, which will come later this week and consists mostly of bugfixes and selftests. s390 changes will also come in the second batch. ARM: - Add large stage-2 mapping (THP) support for non-protected guests when pKVM is enabled, clawing back some performance. - Enable nested virtualisation support on systems that support it, though it is disabled by default. - Add UBSAN support to the standalone EL2 object used in nVHE/hVHE and protected modes. - Large rework of the way KVM tracks architecture features and links them with the effects of control bits. While this has no functional impact, it ensures correctness of emulation (the data is automatically extracted from the published JSON files), and helps dealing with the evolution of the architecture. - Significant changes to the way pKVM tracks ownership of pages, avoiding page table walks by storing the state in the hypervisor's vmemmap. This in turn enables the THP support described above. - New selftest checking the pKVM ownership transition rules - Fixes for FEAT_MTE_ASYNC being accidentally advertised to guests even if the host didn't have it. - Fixes for the address translation emulation, which happened to be rather buggy in some specific contexts. - Fixes for the PMU emulation in NV contexts, decoupling PMCR_EL0.N from the number of counters exposed to a guest and addressing a number of issues in the process. - Add a new selftest for the SVE host state being corrupted by a guest. - Keep HCR_EL2.xMO set at all times for systems running with the kernel at EL2, ensuring that the window for interrupts is slightly bigger, and avoiding a pretty bad erratum on the AmpereOne HW. - Add workaround for AmpereOne's erratum AC04_CPU_23, which suffers from a pretty bad case of TLB corruption unless accesses to HCR_EL2 are heavily synchronised. - Add a per-VM, per-ITS debugfs entry to dump the state of the ITS tables in a human-friendly fashion. - and the usual random cleanups. LoongArch: - Don't flush tlb if the host supports hardware page table walks. - Add KVM selftests support. RISC-V: - Add vector registers to get-reg-list selftest - VCPU reset related improvements - Remove scounteren initialization from VCPU reset - Support VCPU reset from userspace using set_mpstate() ioctl x86: - Initial support for TDX in KVM. This finally makes it possible to use the TDX module to run confidential guests on Intel processors. This is quite a large series, including support for private page tables (managed by the TDX module and mirrored in KVM for efficiency), forwarding some TDVMCALLs to userspace, and handling several special VM exits from the TDX module. This has been in the works for literally years and it's not really possible to describe everything here, so I'll defer to the various merge commits up to and including commit 7bcf7246c42a ('Merge branch 'kvm-tdx-finish-initial' into HEAD')" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (248 commits) x86/tdx: mark tdh_vp_enter() as __flatten Documentation: virt/kvm: remove unreferenced footnote RISC-V: KVM: lock the correct mp_state during reset KVM: arm64: Fix documentation for vgic_its_iter_next() KVM: arm64: np-guest CMOs with PMD_SIZE fixmap KVM: arm64: Stage-2 huge mappings for np-guests KVM: arm64: Add a range to pkvm_mappings KVM: arm64: Convert pkvm_mappings to interval tree KVM: arm64: Add a range to __pkvm_host_test_clear_young_guest() KVM: arm64: Add a range to __pkvm_host_wrprotect_guest() KVM: arm64: Add a range to __pkvm_host_unshare_guest() KVM: arm64: Add a range to __pkvm_host_share_guest() KVM: arm64: Introduce for_each_hyp_page KVM: arm64: Handle huge mappings for np-guest CMOs KVM: arm64: nv: Release faulted-in VNCR page from mmu_lock critical section KVM: arm64: nv: Handle TLBI S1E2 for VNCR invalidation with mmu_lock held KVM: arm64: nv: Hold mmu_lock when invalidating VNCR SW-TLB before translating RISC-V: KVM: add KVM_CAP_RISCV_MP_STATE_RESET RISC-V: KVM: Remove scounteren initialization KVM: RISC-V: remove unnecessary SBI reset state ...
2025-05-28Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "The headline feature is the re-enablement of support for Arm's Scalable Matrix Extension (SME) thanks to a bumper crop of fixes from Mark Rutland. If matrices aren't your thing, then Ryan's page-table optimisation work is much more interesting. Summary: ACPI, EFI and PSCI: - Decouple Arm's "Software Delegated Exception Interface" (SDEI) support from the ACPI GHES code so that it can be used by platforms booted with device-tree - Remove unnecessary per-CPU tracking of the FPSIMD state across EFI runtime calls - Fix a node refcount imbalance in the PSCI device-tree code CPU Features: - Ensure register sanitisation is applied to fields in ID_AA64MMFR4 - Expose AIDR_EL1 to userspace via sysfs, primarily so that KVM guests can reliably query the underlying CPU types from the VMM - Re-enabling of SME support (CONFIG_ARM64_SME) as a result of fixes to our context-switching, signal handling and ptrace code Entry code: - Hook up TIF_NEED_RESCHED_LAZY so that CONFIG_PREEMPT_LAZY can be selected Memory management: - Prevent BSS exports from being used by the early PI code - Propagate level and stride information to the low-level TLB invalidation routines when operating on hugetlb entries - Use the page-table contiguous hint for vmap() mappings with VM_ALLOW_HUGE_VMAP where possible - Optimise vmalloc()/vmap() page-table updates to use "lazy MMU mode" and hook this up on arm64 so that the trailing DSB (used to publish the updates to the hardware walker) can be deferred until the end of the mapping operation - Extend mmap() randomisation for 52-bit virtual addresses (on par with 48-bit addressing) and remove limited support for randomisation of the linear map Perf and PMUs: - Add support for probing the CMN-S3 driver using ACPI - Minor driver fixes to the CMN, Arm-NI and amlogic PMU drivers Selftests: - Fix FPSIMD and SME tests to align with the freshly re-enabled SME support - Fix default setting of the OUTPUT variable so that tests are installed in the right location vDSO: - Replace raw counter access from inline assembly code with a call to the the __arch_counter_get_cntvct() helper function Miscellaneous: - Add some missing header inclusions to the CCA headers - Rework rendering of /proc/cpuinfo to follow the x86-approach and avoid repeated buffer expansion (the user-visible format remains identical) - Remove redundant selection of CONFIG_CRC32 - Extend early error message when failing to map the device-tree blob" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (83 commits) arm64: cputype: Add cputype definition for HIP12 arm64: el2_setup.h: Make __init_el2_fgt labels consistent, again perf/arm-cmn: Add CMN S3 ACPI binding arm64/boot: Disallow BSS exports to startup code arm64/boot: Move global CPU override variables out of BSS arm64/boot: Move init_pgdir[] and init_idmap_pgdir[] into __pi_ namespace perf/arm-cmn: Initialise cmn->cpu earlier kselftest/arm64: Set default OUTPUT path when undefined arm64: Update comment regarding values in __boot_cpu_mode arm64: mm: Drop redundant check in pmd_trans_huge() arm64/mm: Re-organise setting up FEAT_S1PIE registers PIRE0_EL1 and PIR_EL1 arm64/mm: Permit lazy_mmu_mode to be nested arm64/mm: Disable barrier batching in interrupt contexts arm64/cpuinfo: only show one cpu's info in c_show() arm64/mm: Batch barriers when updating kernel mappings mm/vmalloc: Enter lazy mmu mode while manipulating vmalloc ptes arm64/mm: Support huge pte-mapped pages in vmap mm/vmalloc: Gracefully unmap huge ptes mm/vmalloc: Warn on improper use of vunmap_range() arm64/mm: Hoist barriers out of set_ptes_anysz() loop ...
2025-05-27Merge tag 'docs-6.16' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "A moderately busy cycle for documentation this time around: - The most significant change is the replacement of the old kernel-doc script (a monstrous collection of Perl regexes that predates the Git era) with a Python reimplementation. That, too, is a horrifying collection of regexes, but in a much cleaner and more maintainable structure that integrates far better with the Sphinx build system. This change has been in linux-next for the full 6.15 cycle; the small number of problems that turned up have been addressed, seemingly to everybody's satisfaction. The Perl kernel-doc script remains in tree (as scripts/kernel-doc.pl) and can be used with a command-line option if need be. Unless some reason to keep it around materializes, it will probably go away in 6.17. Credit goes to Mauro Carvalho Chehab for doing all this work. - Some RTLA documentation updates - A handful of Chinese translations - The usual collection of typo fixes, general updates, etc" * tag 'docs-6.16' of git://git.lwn.net/linux: (85 commits) Docs: doc-guide: update sphinx.rst Sphinx version number docs: doc-guide: clarify latest theme usage Documentation/scheduler: Fix typo in sched-stats domain field description scripts: kernel-doc: prevent a KeyError when checking output docs: kerneldoc.py: simplify exception handling logic MAINTAINERS: update linux-doc entry to cover new Python scripts docs: align with scripts/syscall.tbl migration Documentation: NTB: Fix typo Documentation: ioctl-number: Update table intro docs: conf.py: drop backward support for old Sphinx versions Docs: driver-api/basics: add kobject_event interfaces Docs: relay: editing cleanups docs: fix "incase" typo in coresight/panic.rst Fix spelling error for 'parallel' docs: admin-guide: fix typos in reporting-issues.rst docs: dmaengine: add explanation for DMA_ASYNC_TX capability Documentation: leds: improve readibility of multicolor doc docs: fix typo in firmware-related section docs: Makefile: Inherit PYTHONPYCACHEPREFIX setting as env variable Documentation: ioctl-number: Update outdated submission info ...
2025-05-27Merge tag 'x86_cache_for_v6.16_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 resource control updates from Borislav Petkov: "Carve out the resctrl filesystem-related code into fs/resctrl/ so that multiple architectures can share the fs API for manipulating their respective hw resource control implementation. This is the second step in the work towards sharing the resctrl filesystem interface, the next one being plugging ARM's MPAM into the aforementioned fs API" * tag 'x86_cache_for_v6.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits) MAINTAINERS: Add reviewers for fs/resctrl x86,fs/resctrl: Move the resctrl filesystem code to live in /fs/resctrl x86/resctrl: Always initialise rid field in rdt_resources_all[] x86/resctrl: Relax some asm #includes x86/resctrl: Prefer alloc(sizeof(*foo)) idiom in rdt_init_fs_context() x86/resctrl: Squelch whitespace anomalies in resctrl core code x86/resctrl: Move pseudo lock prototypes to include/linux/resctrl.h x86/resctrl: Fix types in resctrl_arch_mon_ctx_{alloc,free}() stubs x86/resctrl: Move enum resctrl_event_id to resctrl.h x86/resctrl: Move the filesystem bits to headers visible to fs/resctrl fs/resctrl: Add boiler plate for external resctrl code x86/resctrl: Add 'resctrl' to the title of the resctrl documentation x86/resctrl: Split trace.h x86/resctrl: Expand the width of domid by replacing mon_data_bits x86/resctrl: Add end-marker to the resctrl_event_id enum x86/resctrl: Move is_mba_sc() out of core.c x86/resctrl: Drop __init/__exit on assorted symbols x86/resctrl: Resctrl_exit() teardown resctrl but leave the mount point x86/resctrl: Check all domains are offline in resctrl_exit() x86/resctrl: Rename resctrl_sched_in() to begin with "resctrl_arch_" ...
2025-05-27Merge branch 'for-next/sme-fixes' into for-next/coreWill Deacon
* for-next/sme-fixes: (35 commits) arm64/fpsimd: Allow CONFIG_ARM64_SME to be selected arm64/fpsimd: ptrace: Gracefully handle errors arm64/fpsimd: ptrace: Mandate SVE payload for streaming-mode state arm64/fpsimd: ptrace: Do not present register data for inactive mode arm64/fpsimd: ptrace: Save task state before generating SVE header arm64/fpsimd: ptrace/prctl: Ensure VL changes leave task in a valid state arm64/fpsimd: ptrace/prctl: Ensure VL changes do not resurrect stale data arm64/fpsimd: Make clone() compatible with ZA lazy saving arm64/fpsimd: Clear PSTATE.SM during clone() arm64/fpsimd: Consistently preserve FPSIMD state during clone() arm64/fpsimd: Remove redundant task->mm check arm64/fpsimd: signal: Use SMSTOP behaviour in setup_return() arm64/fpsimd: Add task_smstop_sm() arm64/fpsimd: Factor out {sve,sme}_state_size() helpers arm64/fpsimd: Clarify sve_sync_*() functions arm64/fpsimd: ptrace: Consistently handle partial writes to NT_ARM_(S)SVE arm64/fpsimd: signal: Consistently read FPSIMD context arm64/fpsimd: signal: Mandate SVE payload for streaming-mode state arm64/fpsimd: signal: Clear PSTATE.SM when restoring FPSIMD frame only arm64/fpsimd: Do not discard modified SVE state ...
2025-05-26Merge tag 'x86-core-2025-05-25' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core x86 updates from Ingo Molnar: "Boot code changes: - A large series of changes to reorganize the x86 boot code into a better isolated and easier to maintain base of PIC early startup code in arch/x86/boot/startup/, by Ard Biesheuvel. Motivation & background: | Since commit | | c88d71508e36 ("x86/boot/64: Rewrite startup_64() in C") | | dated Jun 6 2017, we have been using C code on the boot path in a way | that is not supported by the toolchain, i.e., to execute non-PIC C | code from a mapping of memory that is different from the one provided | to the linker. It should have been obvious at the time that this was a | bad idea, given the need to sprinkle fixup_pointer() calls left and | right to manipulate global variables (including non-pointer variables) | without crashing. | | This C startup code has been expanding, and in particular, the SEV-SNP | startup code has been expanding over the past couple of years, and | grown many of these warts, where the C code needs to use special | annotations or helpers to access global objects. This tree includes the first phase of this work-in-progress x86 boot code reorganization. Scalability enhancements and micro-optimizations: - Improve code-patching scalability (Eric Dumazet) - Remove MFENCEs for X86_BUG_CLFLUSH_MONITOR (Andrew Cooper) CPU features enumeration updates: - Thorough reorganization and cleanup of CPUID parsing APIs (Ahmed S. Darwish) - Fix, refactor and clean up the cacheinfo code (Ahmed S. Darwish, Thomas Gleixner) - Update CPUID bitfields to x86-cpuid-db v2.3 (Ahmed S. Darwish) Memory management changes: - Allow temporary MMs when IRQs are on (Andy Lutomirski) - Opt-in to IRQs-off activate_mm() (Andy Lutomirski) - Simplify choose_new_asid() and generate better code (Borislav Petkov) - Simplify 32-bit PAE page table handling (Dave Hansen) - Always use dynamic memory layout (Kirill A. Shutemov) - Make SPARSEMEM_VMEMMAP the only memory model (Kirill A. Shutemov) - Make 5-level paging support unconditional (Kirill A. Shutemov) - Stop prefetching current->mm->mmap_lock on page faults (Mateusz Guzik) - Predict valid_user_address() returning true (Mateusz Guzik) - Consolidate initmem_init() (Mike Rapoport) FPU support and vector computing: - Enable Intel APX support (Chang S. Bae) - Reorgnize and clean up the xstate code (Chang S. Bae) - Make task_struct::thread constant size (Ingo Molnar) - Restore fpu_thread_struct_whitelist() to fix CONFIG_HARDENED_USERCOPY=y (Kees Cook) - Simplify the switch_fpu_prepare() + switch_fpu_finish() logic (Oleg Nesterov) - Always preserve non-user xfeatures/flags in __state_perm (Sean Christopherson) Microcode loader changes: - Help users notice when running old Intel microcode (Dave Hansen) - AMD: Do not return error when microcode update is not necessary (Annie Li) - AMD: Clean the cache if update did not load microcode (Boris Ostrovsky) Code patching (alternatives) changes: - Simplify, reorganize and clean up the x86 text-patching code (Ingo Molnar) - Make smp_text_poke_batch_process() subsume smp_text_poke_batch_finish() (Nikolay Borisov) - Refactor the {,un}use_temporary_mm() code (Peter Zijlstra) Debugging support: - Add early IDT and GDT loading to debug relocate_kernel() bugs (David Woodhouse) - Print the reason for the last reset on modern AMD CPUs (Yazen Ghannam) - Add AMD Zen debugging document (Mario Limonciello) - Fix opcode map (!REX2) superscript tags (Masami Hiramatsu) - Stop decoding i64 instructions in x86-64 mode at opcode (Masami Hiramatsu) CPU bugs and bug mitigations: - Remove X86_BUG_MMIO_UNKNOWN (Borislav Petkov) - Fix SRSO reporting on Zen1/2 with SMT disabled (Borislav Petkov) - Restructure and harmonize the various CPU bug mitigation methods (David Kaplan) - Fix spectre_v2 mitigation default on Intel (Pawan Gupta) MSR API: - Large MSR code and API cleanup (Xin Li) - In-kernel MSR API type cleanups and renames (Ingo Molnar) PKEYS: - Simplify PKRU update in signal frame (Chang S. Bae) NMI handling code: - Clean up, refactor and simplify the NMI handling code (Sohil Mehta) - Improve NMI duration console printouts (Sohil Mehta) Paravirt guests interface: - Restrict PARAVIRT_XXL to 64-bit only (Kirill A. Shutemov) SEV support: - Share the sev_secrets_pa value again (Tom Lendacky) x86 platform changes: - Introduce the <asm/amd/> header namespace (Ingo Molnar) - i2c: piix4, x86/platform: Move the SB800 PIIX4 FCH definitions to <asm/amd/fch.h> (Mario Limonciello) Fixes and cleanups: - x86 assembly code cleanups and fixes (Uros Bizjak) - Misc fixes and cleanups (Andi Kleen, Andy Lutomirski, Andy Shevchenko, Ard Biesheuvel, Bagas Sanjaya, Baoquan He, Borislav Petkov, Chang S. Bae, Chao Gao, Dan Williams, Dave Hansen, David Kaplan, David Woodhouse, Eric Biggers, Ingo Molnar, Josh Poimboeuf, Juergen Gross, Malaya Kumar Rout, Mario Limonciello, Nathan Chancellor, Oleg Nesterov, Pawan Gupta, Peter Zijlstra, Shivank Garg, Sohil Mehta, Thomas Gleixner, Uros Bizjak, Xin Li)" * tag 'x86-core-2025-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (331 commits) x86/bugs: Fix spectre_v2 mitigation default on Intel x86/bugs: Restructure ITS mitigation x86/xen/msr: Fix uninitialized variable 'err' x86/msr: Remove a superfluous inclusion of <asm/asm.h> x86/paravirt: Restrict PARAVIRT_XXL to 64-bit only x86/mm/64: Make 5-level paging support unconditional x86/mm/64: Make SPARSEMEM_VMEMMAP the only memory model x86/mm/64: Always use dynamic memory layout x86/bugs: Fix indentation due to ITS merge x86/cpuid: Rename hypervisor_cpuid_base()/for_each_possible_hypervisor_cpuid_base() to cpuid_base_hypervisor()/for_each_possible_cpuid_base_hypervisor() x86/cpu/intel: Rename CPUID(0x2) descriptors iterator parameter x86/cacheinfo: Rename CPUID(0x2) descriptors iterator parameter x86/cpuid: Rename cpuid_get_leaf_0x2_regs() to cpuid_leaf_0x2() x86/cpuid: Rename have_cpuid_p() to cpuid_feature() x86/cpuid: Set <asm/cpuid/api.h> as the main CPUID header x86/cpuid: Move CPUID(0x2) APIs into <cpuid/api.h> x86/msr: Add rdmsrl_on_cpu() compatibility wrapper x86/mm: Fix kernel-doc descriptions of various pgtable methods x86/asm-offsets: Export certain 'struct cpuinfo_x86' fields for 64-bit asm use too x86/boot: Defer initialization of VM space related global variables ...
2025-05-26Merge tag 'powerpc-6.16-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Madhavan Srinivasan: - Support for dynamic preemption - Migrate powerpc boards GPIO driver to new setter API - Added new PMU for KVM host-wide measurement - Enhancement to htmdump driver to support more functions - Added character device for couple RTAS supported APIs - Minor fixes and cleanup Thanks to Amit Machhiwal, Athira Rajeev, Bagas Sanjaya, Bartosz Golaszewski, Christophe Leroy, Eddie James, Gaurav Batra, Gautam Menghani, Geert Uytterhoeven, Haren Myneni, Hari Bathini, Jiri Slaby (SUSE), Linus Walleij, Michal Suchanek, Naveen N Rao (AMD), Nilay Shroff, Ricardo B. Marlière, Ritesh Harjani (IBM), Sathvika Vasireddy, Shrikanth Hegde, Stephen Rothwell, Sourabh Jain, Thorsten Blum, Vaibhav Jain, Venkat Rao Bagalkote, and Viktor Malik. * tag 'powerpc-6.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (52 commits) MAINTAINERS: powerpc: Remove myself as a reviewer powerpc/iommu: Use str_disabled_enabled() helper powerpc/powermac: Use str_enabled_disabled() and str_on_off() helpers powerpc/mm/fault: Use str_write_read() helper function powerpc: Replace strcpy() with strscpy() in proc_ppc64_init() powerpc/pseries/iommu: Fix kmemleak in TCE table userspace view powerpc/kernel: Fix ppc_save_regs inclusion in build powerpc: Transliterate author name and remove FIXME powerpc/pseries/htmdump: Include header file to get is_kvm_guest() definition KVM: PPC: Book3S HV: Fix IRQ map warnings with XICS on pSeries KVM Guest powerpc/8xx: Reduce alignment constraint for kernel memory powerpc/boot: Fix build with gcc 15 powerpc/pseries/htmdump: Add documentation for H_HTM debugfs interface powerpc/pseries/htmdump: Add htm capabilities support to htmdump module powerpc/pseries/htmdump: Add htm flags support to htmdump module powerpc/pseries/htmdump: Add htm setup support to htmdump module powerpc/pseries/htmdump: Add htm info support to htmdump module powerpc/pseries/htmdump: Add htm status support to htmdump module powerpc/pseries/htmdump: Add htm start support to htmdump module powerpc/pseries/htmdump: Add htm configure support to htmdump module ...
2025-05-23Merge branch kvm-arm64/misc-6.16 into kvmarm-master/nextMarc Zyngier
* kvm-arm64/misc-6.16: : . : Misc changes and improvements for 6.16: : : - Add a new selftest for the SVE host state being corrupted by a guest : : - Keep HCR_EL2.xMO set at all times for systems running with the kernel at EL2, : ensuring that the window for interrupts is slightly bigger, and avoiding : a pretty bad erratum on the AmpereOne HW : : - Replace a couple of open-coded on/off strings with str_on_off() : : - Get rid of the pKVM memblock sorting, which now appears to be superflous : : - Drop superflous clearing of ICH_LR_EOI in the LR when nesting : : - Add workaround for AmpereOne's erratum AC04_CPU_23, which suffers from : a pretty bad case of TLB corruption unless accesses to HCR_EL2 are : heavily synchronised : : - Add a per-VM, per-ITS debugfs entry to dump the state of the ITS tables : in a human-friendly fashion : . KVM: arm64: Fix documentation for vgic_its_iter_next() KVM: arm64: vgic-its: Add debugfs interface to expose ITS tables arm64: errata: Work around AmpereOne's erratum AC04_CPU_23 KVM: arm64: nv: Remove clearing of ICH_LR<n>.EOI if ICH_LR<n>.HW == 1 KVM: arm64: Drop sort_memblock_regions() KVM: arm64: selftests: Add test for SVE host corruption KVM: arm64: Force HCR_EL2.xMO to 1 at all times in VHE mode KVM: arm64: Replace ternary flags with str_on_off() helper Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-05-19arm64: errata: Work around AmpereOne's erratum AC04_CPU_23D Scott Phillips
On AmpereOne AC04, updates to HCR_EL2 can rarely corrupt simultaneous translations for data addresses initiated by load/store instructions. Only instruction initiated translations are vulnerable, not translations from prefetches for example. A DSB before the store to HCR_EL2 is sufficient to prevent older instructions from hitting the window for corruption, and an ISB after is sufficient to prevent younger instructions from hitting the window for corruption. Signed-off-by: D Scott Phillips <scott@os.amperecomputing.com> Reviewed-by: Oliver Upton <oliver.upton@linux.dev> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20250513184514.2678288-1-scott@os.amperecomputing.com Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-05-17x86/mm/64: Make 5-level paging support unconditionalKirill A. Shutemov
Both Intel and AMD CPUs support 5-level paging, which is expected to become more widely adopted in the future. All major x86 Linux distributions have the feature enabled. Remove CONFIG_X86_5LEVEL and related #ifdeffery for it to make it more readable. Suggested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20250516123306.3812286-4-kirill.shutemov@linux.intel.com
2025-05-16x86,fs/resctrl: Move the resctrl filesystem code to live in /fs/resctrlJames Morse
Resctrl is a filesystem interface to hardware that provides cache allocation policy and bandwidth control for groups of tasks or CPUs. To support more than one architecture, resctrl needs to live in /fs/. Move the code that is concerned with the filesystem interface to /fs/resctrl. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Tested-by: Fenghua Yu <fenghuay@nvidia.com> Tested-by: Tony Luck <tony.luck@intel.com> Link: https://lore.kernel.org/20250515165855.31452-25-james.morse@arm.com
2025-05-16x86/resctrl: Add 'resctrl' to the title of the resctrl documentationJames Morse
The resctrl documentation is titled "User Interface for Resource Control feature". Once the documentation follows the code in a move to the filesystem, this appears in the list of filesystems, but doesn't contain the name of the filesystem, making it hard to find. Add 'resctrl' to the title. Suggested-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com> Tested-by: Fenghua Yu <fenghuay@nvidia.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com> Tested-by: Tony Luck <tony.luck@intel.com> Link: https://lore.kernel.org/20250515165855.31452-15-james.morse@arm.com
2025-05-13Merge branch 'x86/platform' into x86/core, to merge dependent commitsIngo Molnar
Prepare to resolve conflicts with an upstream series of fixes that conflict with pending x86 changes: 6f5bf947bab0 Merge tag 'its-for-linus-20250509' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-05-12platform/x86/amd/hsmp: acpi: Add sysfs files to display HSMP telemetrySuma Hegde
Make frequently fetched telemetry available via sysfs. These parameters do not fit in hwmon sensor model, hence make them available via sysfs. Create following sysfs files per acpi device node. * c0_residency_input * prochot_status * smu_fw_version * protocol_version * ddr_max_bw(GB/s) * ddr_utilised_bw_input(GB/s) * ddr_utilised_bw_perc_input(%) * mclk_input(MHz) * fclk_input(MHz) * clk_fmax(MHz) * clk_fmin(MHz) * cclk_freq_limit_input(MHz) * pwr_current_active_freq_limit(MHz) * pwr_current_active_freq_limit_source Signed-off-by: Suma Hegde <suma.hegde@amd.com> Reviewed-by: Naveen Krishna Chatradhi <naveenkrishna.chatradhi@amd.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20250506101542.200811-3-suma.hegde@amd.com Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2025-05-12platform/x86/amd/hsmp: Report power via hwmon sensorsSuma Hegde
Expose power reading and power limits via hwmon power sensors. Signed-off-by: Suma Hegde <suma.hegde@amd.com> Reviewed-by: Naveen Krishna Chatradhi <naveenkrishna.chatradhi@amd.com> Link: https://lore.kernel.org/r/20250506101542.200811-2-suma.hegde@amd.com Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
2025-05-08riscv: hwprobe: Document SiFive xsfvfwmaccqqq vendor extensionCyan Yang
Document the support for matrix multiply accumulate instruction from SiFive using RISCV_HWPROBE_VENDOR_EXT_XSFVFWMACCQQQ. Signed-off-by: Cyan Yang <cyan.yang@sifive.com> Link: https://lore.kernel.org/r/20250418053239.4351-12-cyan.yang@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2025-05-08riscv: hwprobe: Document SiFive xsfvfnrclipxfqf vendor extensionCyan Yang
Document the support for SiFive vendor extensions for FP32-to-int8 Ranged Clip Instructions using RISCV_HWPROBE_VENDOR_EXT_XSFVFNRCLIPXFQF. Signed-off-by: Cyan Yang <cyan.yang@sifive.com> Link: https://lore.kernel.org/r/20250418053239.4351-8-cyan.yang@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2025-05-08riscv: hwprobe: Document SiFive xsfvqmaccdod and xsfvqmaccqoq vendor extensionsCyan Yang
Document the support for sifive vendor extensions using the key RISCV_HWPROBE_KEY_VENDOR_EXT_SIFIVE_0 and two vendor extensions for SiFive Int8 Matrix Multiplication Instructions using RISCV_HWPROBE_VENDOR_EXT_XSFVQMACCDOD and RISCV_HWPROBE_VENDOR_EXT_XSFVQMACCQOQ. Signed-off-by: Cyan Yang <cyan.yang@sifive.com> Link: https://lore.kernel.org/r/20250418053239.4351-4-cyan.yang@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2025-05-08arm64/fpsimd: ptrace/prctl: Ensure VL changes leave task in a valid stateMark Rutland
Currently, vec_set_vector_length() can manipulate a task into an invalid state as a result of a prctl/ptrace syscall which changes the SVE/SME vector length, resulting in several problems: (1) When changing the SVE vector length, if the task initially has PSTATE.ZA==1, and sve_alloc() fails to allocate memory, the task will be left with PSTATE.ZA==1 and sve_state==NULL. This is not a legitimate state, and could result in a subsequent null pointer dereference. (2) When changing the SVE vector length, if the task initially has PSTATE.SM==1, the task will be left with PSTATE.SM==1 and fp_type==FP_STATE_FPSIMD. Streaming mode state always needs to be saved in SVE format, so this is not a legitimate state. Attempting to restore this state may cause a task to erroneously inherit stale streaming mode predicate registers and FFR contents, behaving non-deterministically and potentially leaving information from another task. While in this state, reads of the NT_ARM_SSVE regset will indicate that the registers are not stored in SVE format. For the NT_ARM_SSVE regset specifically, debuggers interpret this as meaning that PSTATE.SM==0. (3) When changing the SME vector length, if the task initially has PSTATE.SM==1, the lower 128 bits of task's streaming mode vector state will be migrated to non-streaming mode, rather than these bits being zeroed as is usually the case for changes to PSTATE.SM. To fix the first issue, we can eagerly allocate the new sve_state and sme_state before modifying the task. This makes it possible to handle memory allocation failure without modifying the task state at all, and removes the need to clear TIF_SVE and TIF_SME. To fix the second issue, we either need to clear PSTATE.SM or not change the saved fp_type. Given we're going to eagerly allocate sve_state and sme_state, the simplest option is to preserve PSTATE.SM and the saves fp_type, and consistently truncate the SVE state. This ensures that the task always stays in a valid state, and by virtue of not exiting streaming mode, this also sidesteps the third issue. I believe these changes should not be problematic for realistic usage: * When the SVE/SME vector length is changed via prctl(), syscall entry will have cleared PSTATE.SM. Unless the task's state has been manipulated via ptrace after entry, the task will have PSTATE.SM==0. * When the SVE/SME vector length is changed via a write to the NT_ARM_SVE or NT_ARM_SSVE regsets, PSTATE.SM will be forced immediately after the length change, and new vector state will be copied from userspace. * When the SME vector length is changed via a write to the NT_ARM_ZA regset, the (S)SVE state is clobbered today, so anyone who cares about the specific state would need to install this after writing to the NT_ARM_ZA regset. As we need to free the old SVE state while TIF_SVE may still be set, we cannot use sve_free(), and using kfree() directly makes it clear that the free pairs with the subsequent assignment. As this leaves sve_free() unused, I've removed the existing sve_free() and renamed __sve_free() to mirror sme_free(). Fixes: 8bd7f91c03d8 ("arm64/sme: Implement traps and syscall handling for SME") Fixes: baa8515281b3 ("arm64/fpsimd: Track the saved FPSIMD state type separately to TIF_SVE") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Spickett <david.spickett@arm.com> Cc: Luis Machado <luis.machado@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20250508132644.1395904-16-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2025-05-08arm64/fpsimd: Make clone() compatible with ZA lazy savingMark Rutland
Linux is intended to be compatible with userspace written to Arm's AAPCS64 procedure call standard [1,2]. For the Scalable Matrix Extension (SME), AAPCS64 was extended with a "ZA lazy saving scheme", where SME's ZA tile is lazily callee-saved and caller-restored. In this scheme, TPIDR2_EL0 indicates whether the ZA tile is live or has been saved by pointing to a "TPIDR2 block" in memory, which has a "za_save_buffer" pointer. This scheme has been implemented in GCC and LLVM, with necessary runtime support implemented in glibc and bionic. AAPCS64 does not specify how the ZA lazy saving scheme is expected to interact with thread creation mechanisms such as fork() and pthread_create(), which would be implemented in terms of the Linux clone syscall. The behaviour implemented by Linux and glibc/bionic doesn't always compose safely, as explained below. Currently the clone syscall is implemented such that PSTATE.ZA and the ZA tile are always inherited by the new task, and TPIDR2_EL0 is inherited unless the 'flags' argument includes CLONE_SETTLS, in which case TPIDR2_EL0 is set to 0/NULL. This doesn't make much sense: (a) TPIDR2_EL0 is part of the calling convention, and changes as control is passed between functions. It is *NOT* used for thread local storage, despite superficial similarity to TPIDR_EL0, which is is used as the TLS register. (b) TPIDR2_EL0 and PSTATE.ZA are tightly coupled in the procedure call standard, and some combinations of states are illegal. In general, manipulating the two independently is not guaranteed to be safe. In practice, code which is compliant with the procedure call standard may issue a clone syscall while in the "ZA dormant" state, where PSTATE.ZA==1 and TPIDR2_EL0 is non-null and indicates that ZA needs to be saved. This can cause a variety of problems, including: * If the implementation of pthread_create() passes CLONE_SETTLS, the new thread will start with PSTATE.ZA==1 and TPIDR2==NULL. Per the procedure call standard this is not a legitimate state for most functions. This can cause data corruption (e.g. as code may rely on PSTATE.ZA being 0 to guarantee that an SMSTART ZA instruction will zero the ZA tile contents), and may result in other undefined behaviour. * If the implementation of pthread_create() does not pass CLONE_SETTLS, the new thread will start with PSTATE.ZA==1 and TPIDR2 pointing to a TPIDR2 block on the parent thread's stack. This can result in a variety of problems, e.g. - The child may write back to the parent's za_save_buffer, corrupting its contents. - The child may read from the TPIDR2 block after the parent has reused this memory for something else, and consequently the child may abort or clobber arbitrary memory. Ideally we'd require that userspace ensures that a task is in the "ZA off" state (with PSTATE.ZA==0 and TPIDR2_EL0==NULL) prior to issuing a clone syscall, and have the kernel force this state for new threads. Unfortunately, contemporary C libraries do not do this, and simply forcing this state within the implementation of clone would break fork(). Instead, we can bodge around this by considering the CLONE_VM flag, and manipulate PSTATE.ZA and TPIDR2_EL0 as a pair. CLONE_VM indicates that the new task will run in the same address space as its parent, and in that case it doesn't make sense to inherit a stale pointer to the parent's TPIDR2 block: * For fork(), CLONE_VM will not be set, and it is safe to inherit both PSTATE.ZA and TPIDR2_EL0 as the new task will have its own copy of the address space, and cannot clobber its parent's stack. * For pthread_create() and vfork(), CLONE_VM will be set, and discarding PSTATE.ZA and TPIDR2_EL0 for the new task doesn't break any existing assumptions in userspace. Implement this behaviour for clone(). We currently inherit PSTATE.ZA in arch_dup_task_struct(), but this does not have access to the clone flags, so move this logic under copy_thread(). Documentation is updated to describe the new behaviour. [1] https://github.com/ARM-software/abi-aa/releases/download/2025Q1/aapcs64.pdf [2] https://github.com/ARM-software/abi-aa/blob/c51addc3dc03e73a016a1e4edf25440bcac76431/aapcs64/aapcs64.rst Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Daniel Kiss <daniel.kiss@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Richard Sandiford <richard.sandiford@arm.com> Cc: Sander De Smalen <sander.desmalen@arm.com> Cc: Tamas Petz <tamas.petz@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Yury Khrustalev <yury.khrustalev@arm.com> Acked-by: Yury Khrustalev <yury.khrustalev@arm.com> Link: https://lore.kernel.org/r/20250508132644.1395904-14-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2025-05-06Documentation:openrisc: Add build instructions with initramfsAnn Yun
Mention how to include initramfs when building the kernel and direct the reader to ramfs-rootfs-initramfs.rst documentation for more details Signed-off-by: Ann Yun <by.ann.yun@gmail.com> Signed-off-by: Stafford Horne <shorne@gmail.com>
2025-05-05x86/CPU/AMD: Print the reason for the last resetYazen Ghannam
The following register contains bits that indicate the cause for the previous reset. PMx000000C0 (FCH::PM::S5_RESET_STATUS) This is useful for debug. The reasons for reset are broken into 6 high level categories. Decode it by category and print during boot. Specifics within a category are split off into debugging documentation. The register is accessed indirectly through a "PM" port in the FCH. Use MMIO access in order to avoid restrictions with legacy port access. Use a late_initcall() to ensure that MMIO has been set up before trying to access the register. This register was introduced with AMD Family 17h, so avoid access on older families. There is no CPUID feature bit for this register. [ bp: Simplify the reason dumping loop. - merge a fix to not access an array element after the last one: https://lore.kernel.org/r/20250505133609.83933-1-superm1@kernel.org Reported-by: James Dutton <james.dutton@gmail.com> ] [ mingo: - Use consistent .rst formatting - Fix 'Sleep' class field to 'ACPI-State' - Standardize pin messages around the 'tripped' verbiage - Remove reference to ring-buffer printing & simplify the wording - Use curly braces for multi-line conditional statements ] Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com> Co-developed-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/20250422234830.2840784-6-superm1@kernel.org