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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>
2025-05-29Merge 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 ...
2025-05-27Merge 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 ...
2025-05-19arm64: 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>
2025-05-08arm64/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>
2025-04-29arm64: Expose AIDR_EL1 via sysfsOliver Upton
The KVM PV ABI recently added a feature that allows the VM to discover the set of physical CPU implementations, identified by a tuple of {MIDR_EL1, REVIDR_EL1, AIDR_EL1}. Unlike other KVM PV features, the expectation is that the VMM implements the hypercall instead of KVM as it has the authoritative view of where the VM gets scheduled. To do this the VMM needs to know the values of these registers on any CPU in the system. While MIDR_EL1 and REVIDR_EL1 are already exposed, AIDR_EL1 is not. Provide it in sysfs along with the other identification registers. Signed-off-by: Oliver Upton <oliver.upton@linux.dev> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20250403231626.3181116-1-oliver.upton@linux.dev Signed-off-by: Will Deacon <will@kernel.org>
2025-04-28arm64/fpsimd: signal: Clear TPIDR2 when delivering signalsMark 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. AAPCS64 does not specify how the ZA lazy saving scheme is expected to interact with signal handling, and the behaviour that AAPCS64 currently recommends for (sig)setjmp() and (sig)longjmp() does not always compose safely with signal handling, as explained below. When Linux delivers a signal, it creates signal frames which contain the original values of PSTATE.ZA, the ZA tile, and TPIDR_EL2. Between saving the original state and entering the signal handler, Linux clears PSTATE.ZA, but leaves TPIDR2_EL0 unchanged. Consequently a signal handler can be entered with PSTATE.ZA=0 (meaning accesses to ZA will trap), while TPIDR_EL0 is non-null (which may indicate that ZA needs to be lazily saved, depending on the contents of the TPIDR2 block). While in this state, libc and/or compiler runtime code, such as longjmp(), may attempt to save ZA. As PSTATE.ZA=0, these accesses will trap, causing the kernel to inject a SIGILL. Note that by virtue of lazy saving occurring in libc and/or C runtime code, this can be triggered by application/library code which is unaware of SME. To avoid the problem above, the kernel must ensure that signal handlers are entered with PSTATE.ZA and TPIDR2_EL0 configured in a manner which complies with the ZA lazy saving scheme. Practically speaking, the only choice is to enter signal handlers with PSTATE.ZA=0 and TPIDR2_EL0=NULL. This change should not impact SME code which does not follow the ZA lazy saving scheme (and hence does not use TPIDR2_EL0). An alternative approach that was considered is to have the signal handler inherit the original values of both PSTATE.ZA and TPIDR2_EL0, relying on lazy save/restore sequences being idempotent and capable of racing safely. This is not safe as signal handlers must be assumed to have a "private ZA" interface, and therefore cannot be entered with PSTATE.ZA=1 and TPIDR2_EL0=NULL, but it is legitimate for signals to be taken from this state. With the kernel fixed to clear TPIDR2_EL0, there are a couple of remaining issues (largely masked by the first issue) that must be fixed in userspace: (1) When a (sig)setjmp() + (sig)longjmp() pair cross a signal boundary, ZA state may be discarded when it needs to be preserved. Currently, the ZA lazy saving scheme recommends that setjmp() does not save ZA, and recommends that longjmp() is responsible for saving ZA. A call to longjmp() in a signal handler will not have visibility of ZA state that existed prior to entry to the signal, and when a longjmp() is used to bypass a usual signal return, unsaved ZA state will be discarded erroneously. To fix this, it is necessary for setjmp() to eagerly save ZA state, and for longjmp() to configure PSTATE.ZA=0 and TPIDR2_EL0=NULL. This works regardless of whether a signal boundary is crossed. (2) When a C++ exception is thrown and crosses a signal boundary before it is caught, ZA state may be discarded when it needs to be preserved. AAPCS64 requires that exception handlers are entered with PSTATE.{SM,ZA}={0,0} and TPIDR2_EL0=NULL, with exception unwind code expected to perform any necessary save of ZA state. Where it is necessary to perform an exception unwind across an exception boundary, the unwind code must recover any necessary ZA state (along with TPIDR2) from signal frames. Fix the kernel as described above, with setup_return() clearing TPIDR2_EL0 when delivering a signal. Folk on CC are working on fixes for the remaining userspace issues, including updates/fixes to the AAPCS64 specification and glibc. [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 Fixes: 39782210eb7e ("arm64/sme: Implement ZA signal handling") Fixes: 39e54499280f ("arm64/signal: Include TPIDR2 in the signal context") Signed-off-by: Mark Rutland <mark.rutland@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> Link: https://lore.kernel.org/r/20250417190113.3778111-1-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2025-04-01Merge tag 'mm-stable-2025-03-30-16-52' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - The series "Enable strict percpu address space checks" from Uros Bizjak uses x86 named address space qualifiers to provide compile-time checking of percpu area accesses. This has caused a small amount of fallout - two or three issues were reported. In all cases the calling code was found to be incorrect. - The series "Some cleanup for memcg" from Chen Ridong implements some relatively monir cleanups for the memcontrol code. - The series "mm: fixes for device-exclusive entries (hmm)" from David Hildenbrand fixes a boatload of issues which David found then using device-exclusive PTE entries when THP is enabled. More work is needed, but this makes thins better - our own HMM selftests now succeed. - The series "mm: zswap: remove z3fold and zbud" from Yosry Ahmed remove the z3fold and zbud implementations. They have been deprecated for half a year and nobody has complained. - The series "mm: further simplify VMA merge operation" from Lorenzo Stoakes implements numerous simplifications in this area. No runtime effects are anticipated. - The series "mm/madvise: remove redundant mmap_lock operations from process_madvise()" from SeongJae Park rationalizes the locking in the madvise() implementation. Performance gains of 20-25% were observed in one MADV_DONTNEED microbenchmark. - The series "Tiny cleanup and improvements about SWAP code" from Baoquan He contains a number of touchups to issues which Baoquan noticed when working on the swap code. - The series "mm: kmemleak: Usability improvements" from Catalin Marinas implements a couple of improvements to the kmemleak user-visible output. - The series "mm/damon/paddr: fix large folios access and schemes handling" from Usama Arif provides a couple of fixes for DAMON's handling of large folios. - The series "mm/damon/core: fix wrong and/or useless damos_walk() behaviors" from SeongJae Park fixes a few issues with the accuracy of kdamond's walking of DAMON regions. - The series "expose mapping wrprotect, fix fb_defio use" from Lorenzo Stoakes changes the interaction between framebuffer deferred-io and core MM. No functional changes are anticipated - this is preparatory work for the future removal of page structure fields. - The series "mm/damon: add support for hugepage_size DAMOS filter" from Usama Arif adds a DAMOS filter which permits the filtering by huge page sizes. - The series "mm: permit guard regions for file-backed/shmem mappings" from Lorenzo Stoakes extends the guard region feature from its present "anon mappings only" state. The feature now covers shmem and file-backed mappings. - The series "mm: batched unmap lazyfree large folios during reclamation" from Barry Song cleans up and speeds up the unmapping for pte-mapped large folios. - The series "reimplement per-vma lock as a refcount" from Suren Baghdasaryan puts the vm_lock back into the vma. Our reasons for pulling it out were largely bogus and that change made the code more messy. This patchset provides small (0-10%) improvements on one microbenchmark. - The series "Docs/mm/damon: misc DAMOS filters documentation fixes and improves" from SeongJae Park does some maintenance work on the DAMON docs. - The series "hugetlb/CMA improvements for large systems" from Frank van der Linden addresses a pile of issues which have been observed when using CMA on large machines. - The series "mm/damon: introduce DAMOS filter type for unmapped pages" from SeongJae Park enables users of DMAON/DAMOS to filter my the page's mapped/unmapped status. - The series "zsmalloc/zram: there be preemption" from Sergey Senozhatsky teaches zram to run its compression and decompression operations preemptibly. - The series "selftests/mm: Some cleanups from trying to run them" from Brendan Jackman fixes a pile of unrelated issues which Brendan encountered while runnimg our selftests. - The series "fs/proc/task_mmu: add guard region bit to pagemap" from Lorenzo Stoakes permits userspace to use /proc/pid/pagemap to determine whether a particular page is a guard page. - The series "mm, swap: remove swap slot cache" from Kairui Song removes the swap slot cache from the allocation path - it simply wasn't being effective. - The series "mm: cleanups for device-exclusive entries (hmm)" from David Hildenbrand implements a number of unrelated cleanups in this code. - The series "mm: Rework generic PTDUMP configs" from Anshuman Khandual implements a number of preparatoty cleanups to the GENERIC_PTDUMP Kconfig logic. - The series "mm/damon: auto-tune aggregation interval" from SeongJae Park implements a feedback-driven automatic tuning feature for DAMON's aggregation interval tuning. - The series "Fix lazy mmu mode" from Ryan Roberts fixes some issues in powerpc, sparc and x86 lazy MMU implementations. Ryan did this in preparation for implementing lazy mmu mode for arm64 to optimize vmalloc. - The series "mm/page_alloc: Some clarifications for migratetype fallback" from Brendan Jackman reworks some commentary to make the code easier to follow. - The series "page_counter cleanup and size reduction" from Shakeel Butt cleans up the page_counter code and fixes a size increase which we accidentally added late last year. - The series "Add a command line option that enables control of how many threads should be used to allocate huge pages" from Thomas Prescher does that. It allows the careful operator to significantly reduce boot time by tuning the parallalization of huge page initialization. - The series "Fix calculations in trace_balance_dirty_pages() for cgwb" from Tang Yizhou fixes the tracing output from the dirty page balancing code. - The series "mm/damon: make allow filters after reject filters useful and intuitive" from SeongJae Park improves the handling of allow and reject filters. Behaviour is made more consistent and the documention is updated accordingly. - The series "Switch zswap to object read/write APIs" from Yosry Ahmed updates zswap to the new object read/write APIs and thus permits the removal of some legacy code from zpool and zsmalloc. - The series "Some trivial cleanups for shmem" from Baolin Wang does as it claims. - The series "fs/dax: Fix ZONE_DEVICE page reference counts" from Alistair Popple regularizes the weird ZONE_DEVICE page refcount handling in DAX, permittig the removal of a number of special-case checks. - The series "refactor mremap and fix bug" from Lorenzo Stoakes is a preparatoty refactoring and cleanup of the mremap() code. - The series "mm: MM owner tracking for large folios (!hugetlb) + CONFIG_NO_PAGE_MAPCOUNT" from David Hildenbrand reworks the manner in which we determine whether a large folio is known to be mapped exclusively into a single MM. - The series "mm/damon: add sysfs dirs for managing DAMOS filters based on handling layers" from SeongJae Park adds a couple of new sysfs directories to ease the management of DAMON/DAMOS filters. - The series "arch, mm: reduce code duplication in mem_init()" from Mike Rapoport consolidates many per-arch implementations of mem_init() into code generic code, where that is practical. - The series "mm/damon/sysfs: commit parameters online via damon_call()" from SeongJae Park continues the cleaning up of sysfs access to DAMON internal data. - The series "mm: page_ext: Introduce new iteration API" from Luiz Capitulino reworks the page_ext initialization to fix a boot-time crash which was observed with an unusual combination of compile and cmdline options. - The series "Buddy allocator like (or non-uniform) folio split" from Zi Yan reworks the code to split a folio into smaller folios. The main benefit is lessened memory consumption: fewer post-split folios are generated. - The series "Minimize xa_node allocation during xarry split" from Zi Yan reduces the number of xarray xa_nodes which are generated during an xarray split. - The series "drivers/base/memory: Two cleanups" from Gavin Shan performs some maintenance work on the drivers/base/memory code. - The series "Add tracepoints for lowmem reserves, watermarks and totalreserve_pages" from Martin Liu adds some more tracepoints to the page allocator code. - The series "mm/madvise: cleanup requests validations and classifications" from SeongJae Park cleans up some warts which SeongJae observed during his earlier madvise work. - The series "mm/hwpoison: Fix regressions in memory failure handling" from Shuai Xue addresses two quite serious regressions which Shuai has observed in the memory-failure implementation. - The series "mm: reliable huge page allocator" from Johannes Weiner makes huge page allocations cheaper and more reliable by reducing fragmentation. - The series "Minor memcg cleanups & prep for memdescs" from Matthew Wilcox is preparatory work for the future implementation of memdescs. - The series "track memory used by balloon drivers" from Nico Pache introduces a way to track memory used by our various balloon drivers. - The series "mm/damon: introduce DAMOS filter type for active pages" from Nhat Pham permits users to filter for active/inactive pages, separately for file and anon pages. - The series "Adding Proactive Memory Reclaim Statistics" from Hao Jia separates the proactive reclaim statistics from the direct reclaim statistics. - The series "mm/vmscan: don't try to reclaim hwpoison folio" from Jinjiang Tu fixes our handling of hwpoisoned pages within the reclaim code. * tag 'mm-stable-2025-03-30-16-52' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (431 commits) mm/page_alloc: remove unnecessary __maybe_unused in order_to_pindex() x86/mm: restore early initialization of high_memory for 32-bits mm/vmscan: don't try to reclaim hwpoison folio mm/hwpoison: introduce folio_contain_hwpoisoned_page() helper cgroup: docs: add pswpin and pswpout items in cgroup v2 doc mm: vmscan: split proactive reclaim statistics from direct reclaim statistics selftests/mm: speed up split_huge_page_test selftests/mm: uffd-unit-tests support for hugepages > 2M docs/mm/damon/design: document active DAMOS filter type mm/damon: implement a new DAMOS filter type for active pages fs/dax: don't disassociate zero page entries MM documentation: add "Unaccepted" meminfo entry selftests/mm: add commentary about 9pfs bugs fork: use __vmalloc_node() for stack allocation docs/mm: Physical Memory: Populate the "Zones" section xen: balloon: update the NR_BALLOON_PAGES state hv_balloon: update the NR_BALLOON_PAGES state balloon_compaction: update the NR_BALLOON_PAGES state meminfo: add a per node counter for balloon drivers mm: remove references to folio in __memcg_kmem_uncharge_page() ...
2025-03-25Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: "Nothing major this time around. Apart from the usual perf/PMU updates, some page table cleanups, the notable features are average CPU frequency based on the AMUv1 counters, CONFIG_HOTPLUG_SMT and MOPS instructions (memcpy/memset) in the uaccess routines. Perf and PMUs: - Support for the 'Rainier' CPU PMU from Arm - Preparatory driver changes and cleanups that pave the way for BRBE support - Support for partial virtualisation of the Apple-M1 PMU - Support for the second event filter in Arm CSPMU designs - Minor fixes and cleanups (CMN and DWC PMUs) - Enable EL2 requirements for FEAT_PMUv3p9 Power, CPU topology: - Support for AMUv1-based average CPU frequency - Run-time SMT control wired up for arm64 (CONFIG_HOTPLUG_SMT). It adds a generic topology_is_primary_thread() function overridden by x86 and powerpc New(ish) features: - MOPS (memcpy/memset) support for the uaccess routines Security/confidential compute: - Fix the DMA address for devices used in Realms with Arm CCA. The CCA architecture uses the address bit to differentiate between shared and private addresses - Spectre-BHB: assume CPUs Linux doesn't know about vulnerable by default Memory management clean-ups: - Drop the P*D_TABLE_BIT definition in preparation for 128-bit PTEs - Some minor page table accessor clean-ups - PIE/POE (permission indirection/overlay) helpers clean-up Kselftests: - MTE: skip hugetlb tests if MTE is not supported on such mappings and user correct naming for sync/async tag checking modes Miscellaneous: - Add a PKEY_UNRESTRICTED definition as 0 to uapi (toolchain people request) - Sysreg updates for new register fields - CPU type info for some Qualcomm Kryo cores" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (72 commits) arm64: mm: Don't use %pK through printk perf/arm_cspmu: Fix missing io.h include arm64: errata: Add newer ARM cores to the spectre_bhb_loop_affected() lists arm64: cputype: Add MIDR_CORTEX_A76AE arm64: errata: Add KRYO 2XX/3XX/4XX silver cores to Spectre BHB safe list arm64: errata: Assume that unknown CPUs _are_ vulnerable to Spectre BHB arm64: errata: Add QCOM_KRYO_4XX_GOLD to the spectre_bhb_k24_list arm64/sysreg: Enforce whole word match for open/close tokens arm64/sysreg: Fix unbalanced closing block arm64: Kconfig: Enable HOTPLUG_SMT arm64: topology: Support SMT control on ACPI based system arch_topology: Support SMT control for OF based system cpu/SMT: Provide a default topology_is_primary_thread() arm64/mm: Define PTDESC_ORDER perf/arm_cspmu: Add PMEVFILT2R support perf/arm_cspmu: Generalise event filtering perf/arm_cspmu: Move register definitons to header arm64/kernel: Always use level 2 or higher for early mappings arm64/mm: Drop PXD_TABLE_BIT arm64/mm: Check pmd_table() in pmd_trans_huge() ...
2025-03-25Merge tag 'irq-drivers-2025-03-23' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq driver updates from Thomas Gleixner: - Support for hard indices on RISC-V. The hart index identifies a hart (core) within a specific interrupt domain in RISC-V's Priviledged Architecture. - Rework of the RISC-V MSI driver This moves the driver over to the generic MSI library and solves the affinity problem of unmaskable PCI/MSI controllers. Unmaskable PCI/MSI controllers are prone to lose interrupts when the MSI message is updated to change the affinity because the message write consists of three 32-bit subsequent writes, which update address and data. As these writes are non-atomic versus the device raising an interrupt, the device can observe a half written update and issue an interrupt on the wrong vector. This is mitiated by a carefully orchestrated step by step update and the observation of an eventually pending interrupt on the CPU which issues the update. The algorithm follows the well established method of the X86 MSI driver. - A new driver for the RISC-V Sophgo SG2042 MSI controller - Overhaul of the Renesas RZQ2L driver Simplification of the probe function by using devm_*() mechanisms, which avoid the endless list of error prone gotos in the failure paths. - Expand the Renesas RZV2H driver to support RZ/G3E SoCs - A workaround for Rockchip 3568002 erratum in the GIC-V3 driver to ensure that the addressing is limited to the lower 32-bit of the physical address space. - Add support for the Allwinner AS23 NMI controller - Expand the IMX irqsteer driver to handle up to 960 input interrupts - The usual small updates, cleanups and device tree changes * tag 'irq-drivers-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits) irqchip/imx-irqsteer: Support up to 960 input interrupts irqchip/sunxi-nmi: Support Allwinner A523 NMI controller dt-bindings: irq: sun7i-nmi: Document the Allwinner A523 NMI controller irqchip/davinci-cp-intc: Remove public header irqchip/renesas-rzv2h: Add RZ/G3E support irqchip/renesas-rzv2h: Update macros ICU_TSSR_TSSEL_{MASK,PREP} irqchip/renesas-rzv2h: Update TSSR_TIEN macro irqchip/renesas-rzv2h: Add field_width to struct rzv2h_hw_info irqchip/renesas-rzv2h: Add max_tssel to struct rzv2h_hw_info irqchip/renesas-rzv2h: Add struct rzv2h_hw_info with t_offs variable irqchip/renesas-rzv2h: Use devm_pm_runtime_enable() irqchip/renesas-rzv2h: Use devm_reset_control_get_exclusive_deasserted() irqchip/renesas-rzv2h: Simplify rzv2h_icu_init() irqchip/renesas-rzv2h: Drop irqchip from struct rzv2h_icu_priv irqchip/renesas-rzv2h: Fix wrong variable usage in rzv2h_tint_set_type() dt-bindings: interrupt-controller: renesas,rzv2h-icu: Document RZ/G3E SoC riscv: sophgo: dts: Add msi controller for SG2042 irqchip: Add the Sophgo SG2042 MSI interrupt controller dt-bindings: interrupt-controller: Add Sophgo SG2042 MSI arm64: dts: rockchip: rk356x: Move PCIe MSI to use GIC ITS instead of MBI ...
2025-03-24Merge tag 'docs-6.15' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "It has been a reasonably busy cycle for docs... - Significant changes throughout the tree to bring Python code up to current standards and raise the minimum Python required to 3.9 Much of this is preparatory to replacing the ancient Perl scripts/kernel-doc horror with a slightly less horrifying Python implementation, expected for 6.16 - Update the minimum Sphinx required to 3.4.3, allowing us to remove a bunch of older compatibility code - Rework and improve the generation of the ABI documentation (All of the above done by Mauro) - Lots of translation updates. Alex Shi and Yanteng Si are taking on responsibility for the Chinese translations going forward; that work will still get to you via docs-next - Try to standardize the format for indicating a developer's affiliation in commit tags - Clarify the TAB's role in CoC enforcement actions - Try to spell out the rules for when a commit tag can name another developer without their explicit permission Plus lots of other typo fixes and updates" * tag 'docs-6.15' of git://git.lwn.net/linux: (98 commits) docs/zh_CN: fix spelling mistake docs/Chinese: change the disclaimer words docs/zh_CN: Add snp-tdx-threat-model index Chinese translation docs: driver-api: firmware: clarify userspace requirements docs: clarify rules wrt tagging other people docs: Remove outdated highuid.rst documentation Documentation: dma-buf: heaps: Add heap name definitions docs/.../submit-checklist: Use Documentation/admin-guide/abi.rst for cross-ref of README docs: Correct installation instruction Documentation: kcsan: fix "Plain Accesses and Data Races" URL in kcsan.rst Documentation/CoC: Spell out the TAB role in enforcement decisions Documentation: ocxl.rst: Update consortium site scripts: get_feat.pl: substitute s390x with s390 scripts/kernel-doc: drop dead code for Wcontents_before_sections scripts/kernel-doc: don't add not needed new lines docs: driver-api/infiniband.rst: fix Kerneldoc markup drivers: firewire: firewire-cdev.h: fix identation on a kernel-doc markup drivers: media: intel-ipu3.h: fix identation on a kernel-doc markup include/asm-generic/io.h: fix kerneldoc markup Docs/arch/arm64: Fix spelling in amu.rst ...
2025-03-17docs: arm64: drop PTDUMP config options from ptdump.rstAnshuman Khandual
Both GENERIC_PTDUMP and PTDUMP_CORE are not user selectable config options. Just drop these from documentation. Link: https://lkml.kernel.org/r/20250226122404.1927473-4-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Suggested-by: Steven Price <steven.price@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-03-11arm64/boot: Enable EL2 requirements for FEAT_PMUv3p9Anshuman Khandual
FEAT_PMUv3p9 registers such as PMICNTR_EL0, PMICFILTR_EL0, and PMUACR_EL1 access from EL1 requires appropriate EL2 fine grained trap configuration via FEAT_FGT2 based trap control registers HDFGRTR2_EL2 and HDFGWTR2_EL2. Otherwise such register accesses will result in traps into EL2. Add a new helper __init_el2_fgt2() which initializes FEAT_FGT2 based fine grained trap control registers HDFGRTR2_EL2 and HDFGWTR2_EL2 (setting the bits nPMICNTR_EL0, nPMICFILTR_EL0 and nPMUACR_EL1) to enable access into PMICNTR_EL0, PMICFILTR_EL0, and PMUACR_EL1 registers. Also update booting.rst with SCR_EL3.FGTEn2 requirement for all FEAT_FGT2 based registers to be accessible in EL2. Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Rob Herring <robh@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Marc Zyngier <maz@kernel.org> Cc: Oliver Upton <oliver.upton@linux.dev> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: kvmarm@lists.linux.dev Fixes: 0bbff9ed8165 ("perf/arm_pmuv3: Add PMUv3.9 per counter EL0 access control") Fixes: d8226d8cfbaf ("perf: arm_pmuv3: Add support for Armv9.4 PMU instruction counter") Tested-by: Rob Herring (Arm) <robh@kernel.org> Reviewed-by: Rob Herring (Arm) <robh@kernel.org> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20250227035119.2025171-1-anshuman.khandual@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2025-03-04Docs/arch/arm64: Fix spelling in amu.rstGabriel
Change though to through. Signed-off-by: Gabriel <gshahrouzi@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/67bd05b5.c80a0220.205997.19df@mx.google.com
2025-02-21irqchip/gic-v3: Add Rockchip 3568002 erratum workaroundDmitry Osipenko
Rockchip RK3566/RK3568 GIC600 integration has DDR addressing limited to the first 32bit of physical address space. Rockchip assigned Erratum ID #3568002 for this issue. Add driver quirk for this Rockchip GIC Erratum. Note, that the 0x0201743b GIC600 ID is not Rockchip-specific and is common for many ARM GICv3 implementations. Hence, there is an extra of_machine_is_compatible() check. Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/all/20250216221634.364158-2-dmitry.osipenko@collabora.com
2025-02-18docs: arm: asymmetric-32bit: Allow creating cross-references for ABIMauro Carvalho Chehab
Now that Documentation/ABI is processed by automarkup, let it generate cross-references for the corresponding ABI file. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/0a989eea90e5d03a36a07760f8b505e074e85c03.1739254867.git.mchehab+huawei@kernel.org
2025-02-04arm64/gcs: Fix documentation for HWCAPMark Brown
In one of the renumberings of the GCS hwcap a stray reference to HWCAP2 was left, fix it. Reported-by: David Spickett <David.Spickett@arm.com> Fixes: 7058bf87cd59 ("arm64/gcs: Document the ABI for Guarded Control Stacks") Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20250124-arm64-gcs-hwcap-doc-v1-1-fa9368b01ca6@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2025-01-24Merge tag 'iommu-updates-v6.14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux Pull iommu updates from Joerg Roedel: "Core changes: - PASID support for the blocked_domain ARM-SMMU Updates: - SMMUv2: - Implement per-client prefetcher configuration on Qualcomm SoCs - Support for the Adreno SMMU on Qualcomm's SDM670 SOC - SMMUv3: - Pretty-printing of event records - Drop the ->domain_alloc_paging implementation in favour of domain_alloc_paging_flags(flags==0) - IO-PGTable: - Generalisation of the page-table walker to enable external walkers (e.g. for debugging unexpected page-faults from the GPU) - Minor fix for handling concatenated PGDs at stage-2 with 16KiB pages - Misc: - Clean-up device probing and replace the crufty probe-deferral hack with a more robust implementation of arm_smmu_get_by_fwnode() - Device-tree binding updates for a bunch of Qualcomm platforms Intel VT-d Updates: - Remove domain_alloc_paging() - Remove capability audit code - Draining PRQ in sva unbind path when FPD bit set - Link cache tags of same iommu unit together AMD-Vi Updates: - Use CMPXCHG128 to update DTE - Cleanups of the domain_alloc_paging() path RiscV IOMMU: - Platform MSI support - Shutdown support Rockchip IOMMU: - Add DT bindings for Rockchip RK3576 More smaller fixes and cleanups" * tag 'iommu-updates-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux: (66 commits) iommu: Use str_enable_disable-like helpers iommu/amd: Fully decode all combinations of alloc_paging_flags iommu/amd: Move the nid to pdom_setup_pgtable() iommu/amd: Change amd_iommu_pgtable to use enum protection_domain_mode iommu/amd: Remove type argument from do_iommu_domain_alloc() and related iommu/amd: Remove dev == NULL checks iommu/amd: Remove domain_alloc() iommu/amd: Remove unused amd_iommu_domain_update() iommu/riscv: Fixup compile warning iommu/arm-smmu-v3: Add missing #include of linux/string_choices.h iommu/arm-smmu-v3: Use str_read_write helper w/ logs iommu/io-pgtable-arm: Add way to debug pgtable walk iommu/io-pgtable-arm: Re-use the pgtable walk for iova_to_phys iommu/io-pgtable-arm: Make pgtable walker more generic iommu/arm-smmu: Add ACTLR data and support for qcom_smmu_500 iommu/arm-smmu: Introduce ACTLR custom prefetcher settings iommu/arm-smmu: Add support for PRR bit setup iommu/arm-smmu: Refactor qcom_smmu structure to include single pointer iommu/arm-smmu: Re-enable context caching in smmu reset operation iommu/vt-d: Link cache tags of same iommu unit together ...
2025-01-21Merge tag 'kthread-for-6.14-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks Pull kthread updates from Frederic Weisbecker: "Kthreads affinity follow either of 4 existing different patterns: 1) Per-CPU kthreads must stay affine to a single CPU and never execute relevant code on any other CPU. This is currently handled by smpboot code which takes care of CPU-hotplug operations. Affinity here is a correctness constraint. 2) Some kthreads _have_ to be affine to a specific set of CPUs and can't run anywhere else. The affinity is set through kthread_bind_mask() and the subsystem takes care by itself to handle CPU-hotplug operations. Affinity here is assumed to be a correctness constraint. 3) Per-node kthreads _prefer_ to be affine to a specific NUMA node. This is not a correctness constraint but merely a preference in terms of memory locality. kswapd and kcompactd both fall into this category. The affinity is set manually like for any other task and CPU-hotplug is supposed to be handled by the relevant subsystem so that the task is properly reaffined whenever a given CPU from the node comes up. Also care should be taken so that the node affinity doesn't cross isolated (nohz_full) cpumask boundaries. 4) Similar to the previous point except kthreads have a _preferred_ affinity different than a node. Both RCU boost kthreads and RCU exp kworkers fall into this category as they refer to "RCU nodes" from a distinctly distributed tree. Currently the preferred affinity patterns (3 and 4) have at least 4 identified users, with more or less success when it comes to handle CPU-hotplug operations and CPU isolation. Each of which do it in its own ad-hoc way. This is an infrastructure proposal to handle this with the following API changes: - kthread_create_on_node() automatically affines the created kthread to its target node unless it has been set as per-cpu or bound with kthread_bind[_mask]() before the first wake-up. - kthread_affine_preferred() is a new function that can be called right after kthread_create_on_node() to specify a preferred affinity different than the specified node. When the preferred affinity can't be applied because the possible targets are offline or isolated (nohz_full), the kthread is affine to the housekeeping CPUs (which means to all online CPUs most of the time or only the non-nohz_full CPUs when nohz_full= is set). kswapd, kcompactd, RCU boost kthreads and RCU exp kworkers have been converted, along with a few old drivers. Summary of the changes: - Consolidate a bunch of ad-hoc implementations of kthread_run_on_cpu() - Introduce task_cpu_fallback_mask() that defines the default last resort affinity of a task to become nohz_full aware - Add some correctness check to ensure kthread_bind() is always called before the first kthread wake up. - Default affine kthread to its preferred node. - Convert kswapd / kcompactd and remove their halfway working ad-hoc affinity implementation - Implement kthreads preferred affinity - Unify kthread worker and kthread API's style - Convert RCU kthreads to the new API and remove the ad-hoc affinity implementation" * tag 'kthread-for-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks: kthread: modify kernel-doc function name to match code rcu: Use kthread preferred affinity for RCU exp kworkers treewide: Introduce kthread_run_worker[_on_cpu]() kthread: Unify kthread_create_on_cpu() and kthread_create_worker_on_cpu() automatic format rcu: Use kthread preferred affinity for RCU boost kthread: Implement preferred affinity mm: Create/affine kswapd to its preferred node mm: Create/affine kcompactd to its preferred node kthread: Default affine kthread to its preferred NUMA node kthread: Make sure kthread hasn't started while binding it sched,arm64: Handle CPU isolation on last resort fallback rq selection arm64: Exclude nohz_full CPUs from 32bits el0 support lib: test_objpool: Use kthread_run_on_cpu() kallsyms: Use kthread_run_on_cpu() soc/qman: test: Use kthread_run_on_cpu() arm/bL_switcher: Use kthread_run_on_cpu()
2025-01-17Merge branch 'for-next/docs' into for-next/coreWill Deacon
* for-next/docs: Documentation: arm64: Remove stale and redundant virtual memory diagrams docs: arm64: Document EL3 requirements for FEAT_PMUv3 docs: arm64: Document EL3 requirements for cpu debug architecture
2025-01-13Documentation: arm64: Remove stale and redundant virtual memory diagramsWill Deacon
The arm64 'memory.rst' file tries to document the virtual memory map and the translation procedure for a couple of kernel configurations. Unfortunately, the virtual memory map changes relatively frequently and we support considerably more configurations than we did when the docs were introduced (e.g. we now have support for 16KiB pages and 52-bit addressing). Furthermore, the Arm ARM is the definitive resource for the translation procedure and so there's little point in duplicating part of that information in the kernel documentation. Rather than continue trying (and failing) to maintain these diagrams, let's rip them out. The kernel page-table can be dumped using CONFIG_PTDUMP_DEBUGFS if necesssary. Link: https://lore.kernel.org/r/20250102065554.1533781-1-sangmoon.kim@samsung.com Reported-by: Sangmoon Kim <sangmoon.kim@samsung.com> Signed-off-by: Will Deacon <will@kernel.org>
2025-01-08arm64: Exclude nohz_full CPUs from 32bits el0 supportFrederic Weisbecker
Nohz full CPUs are not a desirable fallback target to run 32bits el0 applications. If present, prefer a set of housekeeping CPUs that can do the job instead. Otherwise just don't support el0 32 bits. Should the need arise, appropriate support can be introduced in the future. Suggested-by: Will Deacon <will@kernel.org> Acked-by: Will Deacon <will@kernel.org> Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
2025-01-08arm64/hwcap: Describe 2024 dpISA extensions to userspaceMark Brown
The 2024 dpISA introduces a number of architecture features all of which only add new instructions so only require the addition of hwcaps and ID register visibility. Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20250107-arm64-2024-dpisa-v5-3-7578da51fc3d@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2025-01-08arm64: Filter out SVE hwcaps when FEAT_SVE isn't implementedMarc Zyngier
The hwcaps code that exposes SVE features to userspace only considers ID_AA64ZFR0_EL1, while this is only valid when ID_AA64PFR0_EL1.SVE advertises that SVE is actually supported. The expectations are that when ID_AA64PFR0_EL1.SVE is 0, the ID_AA64ZFR0_EL1 register is also 0. So far, so good. Things become a bit more interesting if the HW implements SME. In this case, a few ID_AA64ZFR0_EL1 fields indicate *SME* features. And these fields overlap with their SVE interpretations. But the architecture says that the SME and SVE feature sets must match, so we're still hunky-dory. This goes wrong if the HW implements SME, but not SVE. In this case, we end-up advertising some SVE features to userspace, even if the HW has none. That's because we never consider whether SVE is actually implemented. Oh well. Fix it by restricting all SVE capabilities to ID_AA64PFR0_EL1.SVE being non-zero. The HWCAPS documentation is amended to reflect the actually checks performed by the kernel. Fixes: 06a916feca2b ("arm64: Expose SVE2 features for userspace") Reported-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: stable@vger.kernel.org Reviewed-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20250107-arm64-2024-dpisa-v5-1-7578da51fc3d@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
2025-01-07iommu/arm-smmu: Re-enable context caching in smmu reset operationBibek Kumar Patro
Default MMU-500 reset operation disables context caching in prefetch buffer. It is however expected for context banks using the ACTLR register to retain their prefetch value during reset and runtime suspend. Add config 'ARM_SMMU_MMU_500_CPRE_ERRATA' to gate this errata workaround in default MMU-500 reset operation which defaults to 'Y' and provide option to disable workaround for context caching in prefetch buffer as and when needed. Suggested-by: Will Deacon <will@kernel.org> Signed-off-by: Bibek Kumar Patro <quic_bibekkum@quicinc.com> Link: https://lore.kernel.org/r/20241212151402.159102-2-quic_bibekkum@quicinc.com Signed-off-by: Will Deacon <will@kernel.org>
2024-12-19docs: arm64: Document EL3 requirements for FEAT_PMUv3Anshuman Khandual
This documents EL3 requirements for FEAT_PMUv3. The register field MDCR_EL3 .TPM needs to be cleared for accesses into PMU registers without any trap being generated into EL3. PMUv3 registers like PMCCFILTR_EL0, PMCCNTR_EL0 PMCNTENCLR_EL0, PMCNTENSET_EL0, PMCR_EL0, PMEVCNTR<n>_EL0, PMEVTYPER<n>_EL0 etc are already being accessed for perf HW PMU implementation. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20241211065425.1106683-3-anshuman.khandual@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-12-19docs: arm64: Document EL3 requirements for cpu debug architectureAnshuman Khandual
This documents EL3 requirements for debug architecture. The register field MDCR_EL3.TDA needs to be cleared for accesses into debug registers without any trap being generated into EL3. CPU debug registers like DBGBCR<n>_EL1, DBGBVR<n>_EL1, DBGWCR<n>_EL1, DBGWVR<n>_EL1 and MDSCR_EL1 are already being accessed for HW breakpoint, watchpoint and debug monitor implementations on the platform. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20241211065425.1106683-2-anshuman.khandual@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2024-12-05ACPI/IORT: Add PMCG platform information for HiSilicon HIP09AQinxin Xia
HiSilicon HIP09A platforms using the same SMMU PMCG with HIP09 and thus suffers the same erratum. List them in the PMCG platform information list without introducing a new SMMU PMCG Model. Update the silicon-errata.rst as well. Reviewed-by: Yicong Yang <yangyicong@hisilicon.com> Acked-by: Hanjun Guo <guohanjun@huawei.com> Signed-off-by: Qinxin Xia <xiaqinxin@huawei.com> Link: https://lore.kernel.org/r/20241205013331.1484017-1-xiaqinxin@huawei.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-11-26irqchip/gicv3-its: Add workaround for hip09 ITS erratum 162100801Zhou Wang
When enabling GICv4.1 in hip09, VMAPP fails to clear some caches during the unmap operation, which can causes vSGIs to be lost. To fix the issue, invalidate the related vPE cache through GICR_INVALLR after VMOVP. Suggested-by: Marc Zyngier <maz@kernel.org> Co-developed-by: Nianyao Tang <tangnianyao@huawei.com> Signed-off-by: Nianyao Tang <tangnianyao@huawei.com> Signed-off-by: Zhou Wang <wangzhou1@hisilicon.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Marc Zyngier <maz@kernel.org>
2024-11-23Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "The biggest change here is eliminating the awful idea that KVM had of essentially guessing which pfns are refcounted pages. The reason to do so was that KVM needs to map both non-refcounted pages (for example BARs of VFIO devices) and VM_PFNMAP/VM_MIXMEDMAP VMAs that contain refcounted pages. However, the result was security issues in the past, and more recently the inability to map VM_IO and VM_PFNMAP memory that _is_ backed by struct page but is not refcounted. In particular this broke virtio-gpu blob resources (which directly map host graphics buffers into the guest as "vram" for the virtio-gpu device) with the amdgpu driver, because amdgpu allocates non-compound higher order pages and the tail pages could not be mapped into KVM. This requires adjusting all uses of struct page in the per-architecture code, to always work on the pfn whenever possible. The large series that did this, from David Stevens and Sean Christopherson, also cleaned up substantially the set of functions that provided arch code with the pfn for a host virtual addresses. The previous maze of twisty little passages, all different, is replaced by five functions (__gfn_to_page, __kvm_faultin_pfn, the non-__ versions of these two, and kvm_prefetch_pages) saving almost 200 lines of code. ARM: - Support for stage-1 permission indirection (FEAT_S1PIE) and permission overlays (FEAT_S1POE), including nested virt + the emulated page table walker - Introduce PSCI SYSTEM_OFF2 support to KVM + client driver. This call was introduced in PSCIv1.3 as a mechanism to request hibernation, similar to the S4 state in ACPI - Explicitly trap + hide FEAT_MPAM (QoS controls) from KVM guests. As part of it, introduce trivial initialization of the host's MPAM context so KVM can use the corresponding traps - PMU support under nested virtualization, honoring the guest hypervisor's trap configuration and event filtering when running a nested guest - Fixes to vgic ITS serialization where stale device/interrupt table entries are not zeroed when the mapping is invalidated by the VM - Avoid emulated MMIO completion if userspace has requested synchronous external abort injection - Various fixes and cleanups affecting pKVM, vCPU initialization, and selftests LoongArch: - Add iocsr and mmio bus simulation in kernel. - Add in-kernel interrupt controller emulation. - Add support for virtualization extensions to the eiointc irqchip. PPC: - Drop lingering and utterly obsolete references to PPC970 KVM, which was removed 10 years ago. - Fix incorrect documentation references to non-existing ioctls RISC-V: - Accelerate KVM RISC-V when running as a guest - Perf support to collect KVM guest statistics from host side s390: - New selftests: more ucontrol selftests and CPU model sanity checks - Support for the gen17 CPU model - List registers supported by KVM_GET/SET_ONE_REG in the documentation x86: - Cleanup KVM's handling of Accessed and Dirty bits to dedup code, improve documentation, harden against unexpected changes. Even if the hardware A/D tracking is disabled, it is possible to use the hardware-defined A/D bits to track if a PFN is Accessed and/or Dirty, and that removes a lot of special cases. - Elide TLB flushes when aging secondary PTEs, as has been done in x86's primary MMU for over 10 years. - Recover huge pages in-place in the TDP MMU when dirty page logging is toggled off, instead of zapping them and waiting until the page is re-accessed to create a huge mapping. This reduces vCPU jitter. - Batch TLB flushes when dirty page logging is toggled off. This reduces the time it takes to disable dirty logging by ~3x. - Remove the shrinker that was (poorly) attempting to reclaim shadow page tables in low-memory situations. - Clean up and optimize KVM's handling of writes to MSR_IA32_APICBASE. - Advertise CPUIDs for new instructions in Clearwater Forest - Quirk KVM's misguided behavior of initialized certain feature MSRs to their maximum supported feature set, which can result in KVM creating invalid vCPU state. E.g. initializing PERF_CAPABILITIES to a non-zero value results in the vCPU having invalid state if userspace hides PDCM from the guest, which in turn can lead to save/restore failures. - Fix KVM's handling of non-canonical checks for vCPUs that support LA57 to better follow the "architecture", in quotes because the actual behavior is poorly documented. E.g. most MSR writes and descriptor table loads ignore CR4.LA57 and operate purely on whether the CPU supports LA57. - Bypass the register cache when querying CPL from kvm_sched_out(), as filling the cache from IRQ context is generally unsafe; harden the cache accessors to try to prevent similar issues from occuring in the future. The issue that triggered this change was already fixed in 6.12, but was still kinda latent. - Advertise AMD_IBPB_RET to userspace, and fix a related bug where KVM over-advertises SPEC_CTRL when trying to support cross-vendor VMs. - Minor cleanups - Switch hugepage recovery thread to use vhost_task. These kthreads can consume significant amounts of CPU time on behalf of a VM or in response to how the VM behaves (for example how it accesses its memory); therefore KVM tried to place the thread in the VM's cgroups and charge the CPU time consumed by that work to the VM's container. However the kthreads did not process SIGSTOP/SIGCONT, and therefore cgroups which had KVM instances inside could not complete freezing. Fix this by replacing the kthread with a PF_USER_WORKER thread, via the vhost_task abstraction. Another 100+ lines removed, with generally better behavior too like having these threads properly parented in the process tree. - Revert a workaround for an old CPU erratum (Nehalem/Westmere) that didn't really work; there was really nothing to work around anyway: the broken patch was meant to fix nested virtualization, but the PERF_GLOBAL_CTRL MSR is virtualized and therefore unaffected by the erratum. - Fix 6.12 regression where CONFIG_KVM will be built as a module even if asked to be builtin, as long as neither KVM_INTEL nor KVM_AMD is 'y'. x86 selftests: - x86 selftests can now use AVX. Documentation: - Use rST internal links - Reorganize the introduction to the API document Generic: - Protect vcpu->pid accesses outside of vcpu->mutex with a rwlock instead of RCU, so that running a vCPU on a different task doesn't encounter long due to having to wait for all CPUs become quiescent. In general both reads and writes are rare, but userspace that supports confidential computing is introducing the use of "helper" vCPUs that may jump from one host processor to another. Those will be very happy to trigger a synchronize_rcu(), and the effect on performance is quite the disaster" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (298 commits) KVM: x86: Break CONFIG_KVM_X86's direct dependency on KVM_INTEL || KVM_AMD KVM: x86: add back X86_LOCAL_APIC dependency Revert "KVM: VMX: Move LOAD_IA32_PERF_GLOBAL_CTRL errata handling out of setup_vmcs_config()" KVM: x86: switch hugepage recovery thread to vhost_task KVM: x86: expose MSR_PLATFORM_INFO as a feature MSR x86: KVM: Advertise CPUIDs for new instructions in Clearwater Forest Documentation: KVM: fix malformed table irqchip/loongson-eiointc: Add virt extension support LoongArch: KVM: Add irqfd support LoongArch: KVM: Add PCHPIC user mode read and write functions LoongArch: KVM: Add PCHPIC read and write functions LoongArch: KVM: Add PCHPIC device support LoongArch: KVM: Add EIOINTC user mode read and write functions LoongArch: KVM: Add EIOINTC read and write functions LoongArch: KVM: Add EIOINTC device support LoongArch: KVM: Add IPI user mode read and write function LoongArch: KVM: Add IPI read and write function LoongArch: KVM: Add IPI device support LoongArch: KVM: Add iocsr and mmio bus simulation in kernel KVM: arm64: Pass on SVE mapping failures ...
2024-11-14Merge branch 'for-next/mops' into for-next/coreCatalin Marinas
* for-next/mops: : More FEAT_MOPS (memcpy instructions) uses - in-kernel routines arm64: mops: Document requirements for hypervisors arm64: lib: Use MOPS for copy_page() and clear_page() arm64: lib: Use MOPS for memcpy() routines arm64: mops: Document booting requirement for HCR_EL2.MCE2 arm64: mops: Handle MOPS exceptions from EL1 arm64: probes: Disable kprobes/uprobes on MOPS instructions # Conflicts: # arch/arm64/kernel/entry-common.c
2024-11-14Merge branches 'for-next/gcs', 'for-next/probes', 'for-next/asm-offsets', ↵Catalin Marinas
'for-next/tlb', 'for-next/misc', 'for-next/mte', 'for-next/sysreg', 'for-next/stacktrace', 'for-next/hwcap3', 'for-next/kselftest', 'for-next/crc32', 'for-next/guest-cca', 'for-next/haft' and 'for-next/scs', remote-tracking branch 'arm64/for-next/perf' into for-next/core * arm64/for-next/perf: perf: Switch back to struct platform_driver::remove() perf: arm_pmuv3: Add support for Samsung Mongoose PMU dt-bindings: arm: pmu: Add Samsung Mongoose core compatible perf/dwc_pcie: Fix typos in event names perf/dwc_pcie: Add support for Ampere SoCs ARM: pmuv3: Add missing write_pmuacr() perf/marvell: Marvell PEM performance monitor support perf/arm_pmuv3: Add PMUv3.9 per counter EL0 access control perf/dwc_pcie: Convert the events with mixed case to lowercase perf/cxlpmu: Support missing events in 3.1 spec perf: imx_perf: add support for i.MX91 platform dt-bindings: perf: fsl-imx-ddr: Add i.MX91 compatible drivers perf: remove unused field pmu_node * for-next/gcs: (42 commits) : arm64 Guarded Control Stack user-space support kselftest/arm64: Fix missing printf() argument in gcs/gcs-stress.c arm64/gcs: Fix outdated ptrace documentation kselftest/arm64: Ensure stable names for GCS stress test results kselftest/arm64: Validate that GCS push and write permissions work kselftest/arm64: Enable GCS for the FP stress tests kselftest/arm64: Add a GCS stress test kselftest/arm64: Add GCS signal tests kselftest/arm64: Add test coverage for GCS mode locking kselftest/arm64: Add a GCS test program built with the system libc kselftest/arm64: Add very basic GCS test program kselftest/arm64: Always run signals tests with GCS enabled kselftest/arm64: Allow signals tests to specify an expected si_code kselftest/arm64: Add framework support for GCS to signal handling tests kselftest/arm64: Add GCS as a detected feature in the signal tests kselftest/arm64: Verify the GCS hwcap arm64: Add Kconfig for Guarded Control Stack (GCS) arm64/ptrace: Expose GCS via ptrace and core files arm64/signal: Expose GCS state in signal frames arm64/signal: Set up and restore the GCS context for signal handlers arm64/mm: Implement map_shadow_stack() ... * for-next/probes: : Various arm64 uprobes/kprobes cleanups arm64: insn: Simulate nop instruction for better uprobe performance arm64: probes: Remove probe_opcode_t arm64: probes: Cleanup kprobes endianness conversions arm64: probes: Move kprobes-specific fields arm64: probes: Fix uprobes for big-endian kernels arm64: probes: Fix simulate_ldr*_literal() arm64: probes: Remove broken LDR (literal) uprobe support * for-next/asm-offsets: : arm64 asm-offsets.c cleanup (remove unused offsets) arm64: asm-offsets: remove PREEMPT_DISABLE_OFFSET arm64: asm-offsets: remove DMA_{TO,FROM}_DEVICE arm64: asm-offsets: remove VM_EXEC and PAGE_SZ arm64: asm-offsets: remove MM_CONTEXT_ID arm64: asm-offsets: remove COMPAT_{RT_,SIGFRAME_REGS_OFFSET arm64: asm-offsets: remove VMA_VM_* arm64: asm-offsets: remove TSK_ACTIVE_MM * for-next/tlb: : TLB flushing optimisations arm64: optimize flush tlb kernel range arm64: tlbflush: add __flush_tlb_range_limit_excess() * for-next/misc: : Miscellaneous patches arm64: tls: Fix context-switching of tpidrro_el0 when kpti is enabled arm64/ptrace: Clarify documentation of VL configuration via ptrace acpi/arm64: remove unnecessary cast arm64/mm: Change protval as 'pteval_t' in map_range() arm64: uprobes: Optimize cache flushes for xol slot acpi/arm64: Adjust error handling procedure in gtdt_parse_timer_block() arm64: fix .data.rel.ro size assertion when CONFIG_LTO_CLANG arm64/ptdump: Test both PTE_TABLE_BIT and PTE_VALID for block mappings arm64/mm: Sanity check PTE address before runtime P4D/PUD folding arm64/mm: Drop setting PTE_TYPE_PAGE in pte_mkcont() ACPI: GTDT: Tighten the check for the array of platform timer structures arm64/fpsimd: Fix a typo arm64: Expose ID_AA64ISAR1_EL1.XS to sanitised feature consumers arm64: Return early when break handler is found on linked-list arm64/mm: Re-organize arch_make_huge_pte() arm64/mm: Drop _PROT_SECT_DEFAULT arm64: Add command-line override for ID_AA64MMFR0_EL1.ECV arm64: head: Drop SWAPPER_TABLE_SHIFT arm64: cpufeature: add POE to cpucap_is_possible() arm64/mm: Change pgattr_change_is_safe() arguments as pteval_t * for-next/mte: : Various MTE improvements selftests: arm64: add hugetlb mte tests hugetlb: arm64: add mte support * for-next/sysreg: : arm64 sysreg updates arm64/sysreg: Update ID_AA64MMFR1_EL1 to DDI0601 2024-09 * for-next/stacktrace: : arm64 stacktrace improvements arm64: preserve pt_regs::stackframe during exec*() arm64: stacktrace: unwind exception boundaries arm64: stacktrace: split unwind_consume_stack() arm64: stacktrace: report recovered PCs arm64: stacktrace: report source of unwind data arm64: stacktrace: move dump_backtrace() to kunwind_stack_walk() arm64: use a common struct frame_record arm64: pt_regs: swap 'unused' and 'pmr' fields arm64: pt_regs: rename "pmr_save" -> "pmr" arm64: pt_regs: remove stale big-endian layout arm64: pt_regs: assert pt_regs is a multiple of 16 bytes * for-next/hwcap3: : Add AT_HWCAP3 support for arm64 (also wire up AT_HWCAP4) arm64: Support AT_HWCAP3 binfmt_elf: Wire up AT_HWCAP3 at AT_HWCAP4 * for-next/kselftest: (30 commits) : arm64 kselftest fixes/cleanups kselftest/arm64: Try harder to generate different keys during PAC tests kselftest/arm64: Don't leak pipe fds in pac.exec_sign_all() kselftest/arm64: Corrupt P0 in the irritator when testing SSVE kselftest/arm64: Add FPMR coverage to fp-ptrace kselftest/arm64: Expand the set of ZA writes fp-ptrace does kselftets/arm64: Use flag bits for features in fp-ptrace assembler code kselftest/arm64: Enable build of PAC tests with LLVM=1 kselftest/arm64: Check that SVCR is 0 in signal handlers kselftest/arm64: Fix printf() compiler warnings in the arm64 syscall-abi.c tests kselftest/arm64: Fix printf() warning in the arm64 MTE prctl() test kselftest/arm64: Fix printf() compiler warnings in the arm64 fp tests kselftest/arm64: Fix build with stricter assemblers kselftest/arm64: Test signal handler state modification in fp-stress kselftest/arm64: Provide a SIGUSR1 handler in the kernel mode FP stress test kselftest/arm64: Implement irritators for ZA and ZT kselftest/arm64: Remove unused ADRs from irritator handlers kselftest/arm64: Correct misleading comments on fp-stress irritators kselftest/arm64: Poll less often while waiting for fp-stress children kselftest/arm64: Increase frequency of signal delivery in fp-stress kselftest/arm64: Fix encoding for SVE B16B16 test ... * for-next/crc32: : Optimise CRC32 using PMULL instructions arm64/crc32: Implement 4-way interleave using PMULL arm64/crc32: Reorganize bit/byte ordering macros arm64/lib: Handle CRC-32 alternative in C code * for-next/guest-cca: : Support for running Linux as a guest in Arm CCA arm64: Document Arm Confidential Compute virt: arm-cca-guest: TSM_REPORT support for realms arm64: Enable memory encrypt for Realms arm64: mm: Avoid TLBI when marking pages as valid arm64: Enforce bounce buffers for realm DMA efi: arm64: Map Device with Prot Shared arm64: rsi: Map unprotected MMIO as decrypted arm64: rsi: Add support for checking whether an MMIO is protected arm64: realm: Query IPA size from the RMM arm64: Detect if in a realm and set RIPAS RAM arm64: rsi: Add RSI definitions * for-next/haft: : Support for arm64 FEAT_HAFT arm64: pgtable: Warn unexpected pmdp_test_and_clear_young() arm64: Enable ARCH_HAS_NONLEAF_PMD_YOUNG arm64: Add support for FEAT_HAFT arm64: setup: name 'tcr2' register arm64/sysreg: Update ID_AA64MMFR1_EL1 register * for-next/scs: : Dynamic shadow call stack fixes arm64/scs: Drop unused prototype __pi_scs_patch_vmlinux() arm64/scs: Deal with 64-bit relative offsets in FDE frames arm64/scs: Fix handling of DWARF augmentation data in CIE/FDE frames
2024-11-12arm64/ptrace: Clarify documentation of VL configuration via ptraceMark Brown
When we configure SVE, SSVE or ZA via ptrace we allow the user to configure the vector length and specify any of the flags that are accepted when configuring via prctl(). This includes the S[VM]E_SET_VL_ONEXEC flag which defers the configuration of the VL until an exec(). We don't do anything to limit the provision of register data as part of configuring the _ONEXEC VL but as a function of the VL enumeration support we do this will be interpreted using the vector length currently configured for the process. This is all a bit surprising, and probably we should just not have allowed register data to be specified with _ONEXEC, but it's our ABI so let's add some explicit documentation in both the ABI documents and the source calling out what happens. The comments are also missing the fact that since SME does not have a mandatory 128 bit VL it is possible for VL enumeration to result in the configuration of a higher VL than was requested, cover that too. Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20241106-arm64-sve-ptrace-vl-set-v1-1-3b164e8b559c@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-11-01arm64/gcs: Fix outdated ptrace documentationMark Brown
The ptrace documentation for GCS was written prior to the implementation of clone3() when we still blocked enabling of GCS via ptrace. This restriction was relaxed as part of implementing clone3() support since we implemented support for the GCS not being managed by the kernel but the documentation still mentions the restriction. Update the documentation to reflect what was merged. We have not yet merged clone3() itself but all the support other than in clone() itself is there. Fixes: 7058bf87cd59 ("arm64/gcs: Document the ABI for Guarded Control Stacks") Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20241031-arm64-gcs-doc-disable-v1-1-d7f6ded62046@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-11-01arm64: mops: Document requirements for hypervisorsKristina Martsenko
Add a mops.rst document to clarify in more detail what hypervisors need to do to run a Linux guest on a system with FEAT_MOPS. Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> Link: https://lore.kernel.org/r/20241028185721.52852-1-kristina.martsenko@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-31arm64: cpufeature: discover CPU support for MPAMJames Morse
ARMv8.4 adds support for 'Memory Partitioning And Monitoring' (MPAM) which describes an interface to cache and bandwidth controls wherever they appear in the system. Add support to detect MPAM. Like SVE, MPAM has an extra id register that describes some more properties, including the virtualisation support, which is optional. Detect this separately so we can detect mismatched/insane systems, but still use MPAM on the host even if the virtualisation support is missing. MPAM needs enabling at the highest implemented exception level, otherwise the register accesses trap. The 'enabled' flag is accessible to lower exception levels, but its in a register that traps when MPAM isn't enabled. The cpufeature 'matches' hook is extended to test this on one of the CPUs, so that firmware can emulate MPAM as disabled if it is reserved for use by secure world. Secondary CPUs that appear late could trip cpufeature's 'lower safe' behaviour after the MPAM properties have been advertised to user-space. Add a verify call to ensure late secondaries match the existing CPUs. (If you have a boot failure that bisects here its likely your CPUs advertise MPAM in the id registers, but firmware failed to either enable or MPAM, or emulate the trap as if it were disabled) Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Joey Gouly <joey.gouly@arm.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20241030160317.2528209-4-joey.gouly@arm.com Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
2024-10-23arm64: Document Arm Confidential ComputeSteven Price
Add some documentation on Arm CCA and the requirements for running Linux as a Realm guest. Also update booting.rst to describe the requirement for RIPAS RAM. Reviewed-by: Gavin Shan <gshan@redhat.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Steven Price <steven.price@arm.com> Link: https://lore.kernel.org/r/20241017131434.40935-12-steven.price@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-17arm64: Support AT_HWCAP3Mark Brown
We have filled all 64 bits of AT_HWCAP2 so in order to support discovery of further features provide the framework to use the already defined AT_HWCAP3 for further CPU features. Signed-off-by: Mark Brown <broonie@kernel.org> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20241004-arm64-elf-hwcap3-v2-2-799d1daad8b0@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-17arm64: mops: Document booting requirement for HCR_EL2.MCE2Kristina Martsenko
Document that hypervisors must set HCR_EL2.MCE2 and handle MOPS exceptions when they migrate a vCPU to another type of CPU, as Linux may not be able to handle the exception at all times. As one example, when running under nested virtualization, KVM does not handle MOPS exceptions from the nVHE/hVHE EL2 hyp as the hyp is never migrated, so the host hypervisor needs to handle them. There may be other situations (now or in the future) where the kernel can't handle an unexpected MOPS exception, so require that the hypervisor handles them. Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> Link: https://lore.kernel.org/r/20240930161051.3777828-4-kristina.martsenko@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-04arm64: Subscribe Microsoft Azure Cobalt 100 to erratum 3194386Easwar Hariharan
Add the Microsoft Azure Cobalt 100 CPU to the list of CPUs suffering from erratum 3194386 added in commit 75b3c43eab59 ("arm64: errata: Expand speculative SSBS workaround") CC: Mark Rutland <mark.rutland@arm.com> CC: James More <james.morse@arm.com> CC: Will Deacon <will@kernel.org> CC: stable@vger.kernel.org # 6.6+ Signed-off-by: Easwar Hariharan <eahariha@linux.microsoft.com> Link: https://lore.kernel.org/r/20241003225239.321774-1-eahariha@linux.microsoft.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-04arm64/hwcap: Add hwcap for GCSMark Brown
Provide a hwcap to enable userspace to detect support for GCS. Signed-off-by: Mark Brown <broonie@kernel.org> Acked-by: Yury Khrustalev <yury.khrustalev@arm.com> Link: https://lore.kernel.org/r/20241001-arm64-gcs-v13-18-222b78d87eee@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-04arm64/gcs: Document the ABI for Guarded Control StacksMark Brown
Add some documentation of the userspace ABI for Guarded Control Stacks. Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Yury Khrustalev <yury.khrustalev@arm.com> Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20241001-arm64-gcs-v13-7-222b78d87eee@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-04arm64: Document boot requirements for Guarded Control StacksMark Brown
FEAT_GCS introduces a number of new system registers, we require that access to these registers is not trapped when we identify that the feature is present. There is also a HCRX_EL2 control to make GCS operations functional. Since if GCS is enabled any function call instruction will cause a fault we also require that the feature be specifically disabled, existing kernels implicitly have this requirement and especially given that the MMU must be disabled it is difficult to see a situation where leaving GCS enabled would be reasonable. Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20241001-arm64-gcs-v13-6-222b78d87eee@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-10-01arm64: errata: Expand speculative SSBS workaround once moreMark Rutland
A number of Arm Ltd CPUs suffer from errata whereby an MSR to the SSBS special-purpose register does not affect subsequent speculative instructions, permitting speculative store bypassing for a window of time. We worked around this for a number of CPUs in commits: * 7187bb7d0b5c7dfa ("arm64: errata: Add workaround for Arm errata 3194386 and 3312417") * 75b3c43eab594bfb ("arm64: errata: Expand speculative SSBS workaround") * 145502cac7ea70b5 ("arm64: errata: Expand speculative SSBS workaround (again)") Since then, a (hopefully final) batch of updates have been published, with two more affected CPUs. For the affected CPUs the existing mitigation is sufficient, as described in their respective Software Developer Errata Notice (SDEN) documents: * Cortex-A715 (MP148) SDEN v15.0, erratum 3456084 https://developer.arm.com/documentation/SDEN-2148827/1500/ * Neoverse-N3 (MP195) SDEN v5.0, erratum 3456111 https://developer.arm.com/documentation/SDEN-3050973/0500/ Enable the existing mitigation by adding the relevant MIDRs to erratum_spec_ssbs_list, and update silicon-errata.rst and the Kconfig text accordingly. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20240930111705.3352047-3-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-09-17Merge tag 'docs-6.12' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation update from Jonathan Corbet: "Another relatively mundane cycle for docs: - The beginning of an EEVDF scheduler document - More Chinese translations - A rethrashing of our bisection documentation ...plus the usual array of smaller fixes, and more than the usual number of typo fixes" * tag 'docs-6.12' of git://git.lwn.net/linux: (48 commits) Remove duplicate "and" in 'Linux NVMe docs. docs:filesystems: fix spelling and grammar mistakes docs:filesystem: fix mispelled words on autofs page docs:mm: fixed spelling and grammar mistakes on vmalloc kernel stack page Documentation: PCI: fix typo in pci.rst docs/zh_CN: add the translation of kbuild/gcc-plugins.rst docs/process: fix typos docs:mm: fix spelling mistakes in heterogeneous memory management page accel/qaic: Fix a typo docs/zh_CN: update the translation of security-bugs docs: block: Fix grammar and spelling mistakes in bfq-iosched.rst Documentation: Fix spelling mistakes Documentation/gpu: Fix typo in Documentation/gpu/komeda-kms.rst scripts: sphinx-pre-install: remove unnecessary double check for $cur_version Loongarch: KVM: Add KVM hypercalls documentation for LoongArch Documentation: Document the kernel flag bdev_allow_write_mounted docs: scheduler: completion: Update member of struct completion docs: kerneldoc-preamble.sty: Suppress extra spaces in CJK literal blocks docs: submitting-patches: Advertise b4 docs: update dev-tools/kcsan.rst url about KTSAN ...
2024-09-12Merge branch 'for-next/poe' into for-next/coreWill Deacon
* for-next/poe: (31 commits) arm64: pkeys: remove redundant WARN kselftest/arm64: Add test case for POR_EL0 signal frame records kselftest/arm64: parse POE_MAGIC in a signal frame kselftest/arm64: add HWCAP test for FEAT_S1POE selftests: mm: make protection_keys test work on arm64 selftests: mm: move fpregs printing kselftest/arm64: move get_header() arm64: add Permission Overlay Extension Kconfig arm64: enable PKEY support for CPUs with S1POE arm64: enable POE and PIE to coexist arm64/ptrace: add support for FEAT_POE arm64: add POE signal support arm64: implement PKEYS support arm64: add pte_access_permitted_no_overlay() arm64: handle PKEY/POE faults arm64: mask out POIndex when modifying a PTE arm64: convert protection key into vm_flags and pgprot values arm64: add POIndex defines arm64: re-order MTE VM_ flags arm64: enable the Permission Overlay Extension for EL0 ...
2024-09-12Merge branch 'for-next/errata' into for-next/coreWill Deacon
* for-next/errata: arm64: errata: Enable the AC03_CPU_38 workaround for ampere1a
2024-09-05Documentation: Fix spelling mistakesAmit Vadhavana
Correct spelling mistakes in the documentation to improve readability. Signed-off-by: Amit Vadhavana <av2082000@gmail.com> Reviewed-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20240817072724.6861-1-av2082000@gmail.com
2024-09-04arm64: enable the Permission Overlay Extension for EL0Joey Gouly
Expose a HWCAP and ID_AA64MMFR3_EL1_S1POE to userspace, so they can be used to check if the CPU supports the feature. Signed-off-by: Joey Gouly <joey.gouly@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Link: https://lore.kernel.org/r/20240822151113.1479789-12-joey.gouly@arm.com Signed-off-by: Will Deacon <will@kernel.org>