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2026-02-12Merge tag 'riscv-for-linus-7.0-mw1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Paul Walmsley: - Add support for control flow integrity for userspace processes. This is based on the standard RISC-V ISA extensions Zicfiss and Zicfilp - Improve ptrace behavior regarding vector registers, and add some selftests - Optimize our strlen() assembly - Enable the ISO-8859-1 code page as built-in, similar to ARM64, for EFI volume mounting - Clean up some code slightly, including defining copy_user_page() as copy_page() rather than memcpy(), aligning us with other architectures; and using max3() to slightly simplify an expression in riscv_iommu_init_check() * tag 'riscv-for-linus-7.0-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (42 commits) riscv: lib: optimize strlen loop efficiency selftests: riscv: vstate_exec_nolibc: Use the regular prctl() function selftests: riscv: verify ptrace accepts valid vector csr values selftests: riscv: verify ptrace rejects invalid vector csr inputs selftests: riscv: verify syscalls discard vector context selftests: riscv: verify initial vector state with ptrace selftests: riscv: test ptrace vector interface riscv: ptrace: validate input vector csr registers riscv: csr: define vtype register elements riscv: vector: init vector context with proper vlenb riscv: ptrace: return ENODATA for inactive vector extension kselftest/riscv: add kselftest for user mode CFI riscv: add documentation for shadow stack riscv: add documentation for landing pad / indirect branch tracking riscv: create a Kconfig fragment for shadow stack and landing pad support arch/riscv: add dual vdso creation logic and select vdso based on hw arch/riscv: compile vdso with landing pad and shadow stack note riscv: enable kernel access to shadow stack memory via the FWFT SBI call riscv: add kernel command line option to opt out of user CFI riscv/hwprobe: add zicfilp / zicfiss enumeration in hwprobe ...
2026-02-12Merge tag 'mm-stable-2026-02-11-19-22' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "powerpc/64s: do not re-activate batched TLB flush" makes arch_{enter|leave}_lazy_mmu_mode() nest properly (Alexander Gordeev) It adds a generic enter/leave layer and switches architectures to use it. Various hacks were removed in the process. - "zram: introduce compressed data writeback" implements data compression for zram writeback (Richard Chang and Sergey Senozhatsky) - "mm: folio_zero_user: clear page ranges" adds clearing of contiguous page ranges for hugepages. Large improvements during demand faulting are demonstrated (David Hildenbrand) - "memcg cleanups" tidies up some memcg code (Chen Ridong) - "mm/damon: introduce {,max_}nr_snapshots and tracepoint for damos stats" improves DAMOS stat's provided information, deterministic control, and readability (SeongJae Park) - "selftests/mm: hugetlb cgroup charging: robustness fixes" fixes a few issues in the hugetlb cgroup charging selftests (Li Wang) - "Fix va_high_addr_switch.sh test failure - again" addresses several issues in the va_high_addr_switch test (Chunyu Hu) - "mm/damon/tests/core-kunit: extend existing test scenarios" improves the KUnit test coverage for DAMON (Shu Anzai) - "mm/khugepaged: fix dirty page handling for MADV_COLLAPSE" fixes a glitch in khugepaged which was causing madvise(MADV_COLLAPSE) to transiently return -EAGAIN (Shivank Garg) - "arch, mm: consolidate hugetlb early reservation" reworks and consolidates a pile of straggly code related to reservation of hugetlb memory from bootmem and creation of CMA areas for hugetlb (Mike Rapoport) - "mm: clean up anon_vma implementation" cleans up the anon_vma implementation in various ways (Lorenzo Stoakes) - "tweaks for __alloc_pages_slowpath()" does a little streamlining of the page allocator's slowpath code (Vlastimil Babka) - "memcg: separate private and public ID namespaces" cleans up the memcg ID code and prevents the internal-only private IDs from being exposed to userspace (Shakeel Butt) - "mm: hugetlb: allocate frozen gigantic folio" cleans up the allocation of frozen folios and avoids some atomic refcount operations (Kefeng Wang) - "mm/damon: advance DAMOS-based LRU sorting" improves DAMOS's movement of memory betewwn the active and inactive LRUs and adds auto-tuning of the ratio-based quotas and of monitoring intervals (SeongJae Park) - "Support page table check on PowerPC" makes CONFIG_PAGE_TABLE_CHECK_ENFORCED work on powerpc (Andrew Donnellan) - "nodemask: align nodes_and{,not} with underlying bitmap ops" makes nodes_and() and nodes_andnot() propagate the return values from the underlying bit operations, enabling some cleanup in calling code (Yury Norov) - "mm/damon: hide kdamond and kdamond_lock from API callers" cleans up some DAMON internal interfaces (SeongJae Park) - "mm/khugepaged: cleanups and scan limit fix" does some cleanup work in khupaged and fixes a scan limit accounting issue (Shivank Garg) - "mm: balloon infrastructure cleanups" goes to town on the balloon infrastructure and its page migration function. Mainly cleanups, also some locking simplification (David Hildenbrand) - "mm/vmscan: add tracepoint and reason for kswapd_failures reset" adds additional tracepoints to the page reclaim code (Jiayuan Chen) - "Replace wq users and add WQ_PERCPU to alloc_workqueue() users" is part of Marco's kernel-wide migration from the legacy workqueue APIs over to the preferred unbound workqueues (Marco Crivellari) - "Various mm kselftests improvements/fixes" provides various unrelated improvements/fixes for the mm kselftests (Kevin Brodsky) - "mm: accelerate gigantic folio allocation" greatly speeds up gigantic folio allocation, mainly by avoiding unnecessary work in pfn_range_valid_contig() (Kefeng Wang) - "selftests/damon: improve leak detection and wss estimation reliability" improves the reliability of two of the DAMON selftests (SeongJae Park) - "mm/damon: cleanup kdamond, damon_call(), damos filter and DAMON_MIN_REGION" does some cleanup work in the core DAMON code (SeongJae Park) - "Docs/mm/damon: update intro, modules, maintainer profile, and misc" performs maintenance work on the DAMON documentation (SeongJae Park) - "mm: add and use vma_assert_stabilised() helper" refactors and cleans up the core VMA code. The main aim here is to be able to use the mmap write lock's lockdep state to perform various assertions regarding the locking which the VMA code requires (Lorenzo Stoakes) - "mm, swap: swap table phase II: unify swapin use" removes some old swap code (swap cache bypassing and swap synchronization) which wasn't working very well. Various other cleanups and simplifications were made. The end result is a 20% speedup in one benchmark (Kairui Song) - "enable PT_RECLAIM on more 64-bit architectures" makes PT_RECLAIM available on 64-bit alpha, loongarch, mips, parisc, and um. Various cleanups were performed along the way (Qi Zheng) * tag 'mm-stable-2026-02-11-19-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (325 commits) mm/memory: handle non-split locks correctly in zap_empty_pte_table() mm: move pte table reclaim code to memory.c mm: make PT_RECLAIM depends on MMU_GATHER_RCU_TABLE_FREE mm: convert __HAVE_ARCH_TLB_REMOVE_TABLE to CONFIG_HAVE_ARCH_TLB_REMOVE_TABLE config um: mm: enable MMU_GATHER_RCU_TABLE_FREE parisc: mm: enable MMU_GATHER_RCU_TABLE_FREE mips: mm: enable MMU_GATHER_RCU_TABLE_FREE LoongArch: mm: enable MMU_GATHER_RCU_TABLE_FREE alpha: mm: enable MMU_GATHER_RCU_TABLE_FREE mm: change mm/pt_reclaim.c to use asm/tlb.h instead of asm-generic/tlb.h mm/damon/stat: remove __read_mostly from memory_idle_ms_percentiles zsmalloc: make common caches global mm: add SPDX id lines to some mm source files mm/zswap: use %pe to print error pointers mm/vmscan: use %pe to print error pointers mm/readahead: fix typo in comment mm: khugepaged: fix NR_FILE_PAGES and NR_SHMEM in collapse_file() mm: refactor vma_map_pages to use vm_insert_pages mm/damon: unify address range representation with damon_addr_range mm/cma: replace snprintf with strscpy in cma_new_area ...
2026-02-10Merge tag 'x86_paravirt_for_v7.0_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 paravirt updates from Borislav Petkov: - A nice cleanup to the paravirt code containing a unification of the paravirt clock interface, taming the include hell by splitting the pv_ops structure and removing of a bunch of obsolete code (Juergen Gross) * tag 'x86_paravirt_for_v7.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) x86/paravirt: Use XOR r32,r32 to clear register in pv_vcpu_is_preempted() x86/paravirt: Remove trailing semicolons from alternative asm templates x86/pvlocks: Move paravirt spinlock functions into own header x86/paravirt: Specify pv_ops array in paravirt macros x86/paravirt: Allow pv-calls outside paravirt.h objtool: Allow multiple pv_ops arrays x86/xen: Drop xen_mmu_ops x86/xen: Drop xen_cpu_ops x86/xen: Drop xen_irq_ops x86/paravirt: Move pv_native_*() prototypes to paravirt.c x86/paravirt: Introduce new paravirt-base.h header x86/paravirt: Move paravirt_sched_clock() related code into tsc.c x86/paravirt: Use common code for paravirt_steal_clock() riscv/paravirt: Use common code for paravirt_steal_clock() loongarch/paravirt: Use common code for paravirt_steal_clock() arm64/paravirt: Use common code for paravirt_steal_clock() arm/paravirt: Use common code for paravirt_steal_clock() sched: Move clock related paravirt code to kernel/sched paravirt: Remove asm/paravirt_api_clock.h x86/paravirt: Move thunk macros to paravirt_types.h ...
2026-02-09riscv: csr: define vtype register elementsSergey Matyukevich
Define masks and shifts for vtype CSR according to the vector specs: - v0.7.1 used in early T-Head cores, known as xtheadvector in the kernel - v1.0 Signed-off-by: Sergey Matyukevich <geomatsi@gmail.com> Reviewed-by: Andy Chiu <andybnac@gmail.com> Tested-by: Andy Chiu <andybnac@gmail.com> Link: https://patch.msgid.link/20251214163537.1054292-4-geomatsi@gmail.com Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-29arch/riscv: add dual vdso creation logic and select vdso based on hwDeepak Gupta
Shadow stack instructions are taken from the Zimop ISA extension, which is mandated on RVA23. Any userspace with shadow stack instructions in it will fault on hardware that doesn't have support for Zimop. Thus, a shadow stack-enabled userspace can't be run on hardware that doesn't support Zimop. It's not known how Linux userspace providers will respond to this kind of binary fragmentation. In order to keep kernel portable across different hardware, 'arch/riscv/kernel/vdso_cfi' is created which has Makefile logic to compile 'arch/riscv/kernel/vdso' sources with CFI flags, and 'arch/riscv/kernel/vdso.c' is modified to select the appropriate vdso depending on whether the underlying CPU implements the Zimop extension. Since the offset of vdso symbols will change due to having two different vdso binaries, there is added logic to include a new generated vdso offset header and dynamically select the offset (like for rt_sigreturn). Signed-off-by: Deepak Gupta <debug@rivosinc.com> Acked-by: Charles Mirabile <cmirabil@redhat.com> Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> # QEMU, custom CVA6 Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com> Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-24-b55691eacf4f@rivosinc.com [pjw@kernel.org: cleaned up patch description] Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-29arch/riscv: compile vdso with landing pad and shadow stack noteJim Shu
User mode tasks compiled with Zicfilp may call indirectly into the vdso (like hwprobe indirect calls). Add support for compiling landing pads into the vdso. Landing pad instructions in the vdso will be no-ops for tasks which have not enabled landing pads. Furthermore, add support for the C sources of the vdso to be compiled with shadow stack and landing pads enabled as well. Landing pad and shadow stack instructions are emitted only when the VDSO_CFI cflags option is defined during compile. Signed-off-by: Jim Shu <jim.shu@sifive.com> Reviewed-by: Zong Li <zong.li@sifive.com> Signed-off-by: Deepak Gupta <debug@rivosinc.com> Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> # QEMU, custom CVA6 Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com> Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-23-b55691eacf4f@rivosinc.com [pjw@kernel.org: cleaned up patch description, issues reported by checkpatch] Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-29riscv: add kernel command line option to opt out of user CFIDeepak Gupta
Add a kernel command line option to disable part or all of user CFI. User backward CFI and forward CFI can be controlled independently. The kernel command line parameter "riscv_nousercfi" can take the following values: - "all" : Disable forward and backward cfi both - "bcfi" : Disable backward cfi - "fcfi" : Disable forward cfi Signed-off-by: Deepak Gupta <debug@rivosinc.com> Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> # QEMU, custom CVA6 Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com> Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-21-b55691eacf4f@rivosinc.com [pjw@kernel.org: fixed warnings from checkpatch; cleaned up patch description, doc, printk text] Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-29riscv: hwprobe: add support for RISCV_HWPROBE_KEY_IMA_EXT_1Paul Walmsley
We've run out of bits to describe RISC-V ISA extensions in our initial hwprobe key, RISCV_HWPROBE_KEY_IMA_EXT_0. So, let's add RISCV_HWPROBE_KEY_IMA_EXT_1, along with the framework to set the appropriate hwprobe tuple, and add testing for it. Based on a suggestion from Andrew Jones <andrew.jones@oss.qualcomm.com>, also fix the documentation for RISCV_HWPROBE_KEY_IMA_EXT_0. Reviewed-by: Andrew Jones <andrew.jones@oss.qualcomm.com> Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-29riscv/signal: save and restore the shadow stack on a signalDeepak Gupta
Save the shadow stack pointer in the sigcontext structure when delivering a signal. Restore the shadow stack pointer from sigcontext on sigreturn. As part of the save operation, the kernel uses the 'ssamoswap' instruction to save a snapshot of the current shadow stack on the shadow stack itself (this can be called a "save token"). During restore on sigreturn, the kernel retrieves the save token from the top of the shadow stack and validates it. This ensures that user mode can't arbitrarily pivot to any shadow stack address without having a token and thus provides a strong security assurance during the window between signal delivery and sigreturn. Use an ABI-compatible way of saving/restoring the shadow stack pointer into the signal stack. This follows the vector extension, where extra registers are placed in a form of extension header + extension body in the stack. The extension header indicates the size of the extra architectural states plus the size of header itself, and a magic identifier for the extension. Then, the extension body contains the new architectural states in the form defined by uapi. Signed-off-by: Andy Chiu <andy.chiu@sifive.com> Signed-off-by: Deepak Gupta <debug@rivosinc.com> Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com> Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-17-b55691eacf4f@rivosinc.com [pjw@kernel.org: cleaned patch description, code comments; resolved checkpatch warning] Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-29riscv/traps: Introduce software check exception and uprobe handlingDeepak Gupta
The Zicfiss and Zicfilp extensions introduce a new exception, the 'software check exception', in the privileged ISA, with cause code = 18. This patch implements support for software check exceptions. Additionally, the patch implements a CFI violation handler which checks the code in the xtval register. If xtval=2, the software check exception happened because of an indirect branch that didn't land on a 4 byte aligned PC or on a 'lpad' instruction, or the label value embedded in 'lpad' didn't match the label value set in the x7 register. If xtval=3, the software check exception happened due to a mismatch between the link register (x1 or x5) and the top of shadow stack (on execution of `sspopchk`). In case of a CFI violation, SIGSEGV is raised with code=SEGV_CPERR. SEGV_CPERR was introduced by the x86 shadow stack patches. To keep uprobes working, handle the uprobe event first before reporting the CFI violation in the software check exception handler. This is because, when the landing pad is activated, if the uprobe point is set at the lpad instruction at the beginning of a function, the system triggers a software check exception instead of an ebreak exception due to the exception priority. This would prevent uprobe from working. Reviewed-by: Zong Li <zong.li@sifive.com> Co-developed-by: Zong Li <zong.li@sifive.com> Signed-off-by: Zong Li <zong.li@sifive.com> Signed-off-by: Deepak Gupta <debug@rivosinc.com> Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> # QEMU, custom CVA6 Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com> Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-15-b55691eacf4f@rivosinc.com [pjw@kernel.org: cleaned up the patch description] Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-29riscv: Implement indirect branch tracking prctlsDeepak Gupta
This patch adds a RISC-V implementation of the following prctls: PR_SET_INDIR_BR_LP_STATUS, PR_GET_INDIR_BR_LP_STATUS and PR_LOCK_INDIR_BR_LP_STATUS. Reviewed-by: Zong Li <zong.li@sifive.com> Signed-off-by: Deepak Gupta <debug@rivosinc.com> Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com> Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-14-b55691eacf4f@rivosinc.com [pjw@kernel.org: clean up patch description] Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-29riscv: Implement arch-agnostic shadow stack prctlsDeepak Gupta
Implement an architecture-agnostic prctl() interface for setting and getting shadow stack status. The prctls implemented are PR_GET_SHADOW_STACK_STATUS, PR_SET_SHADOW_STACK_STATUS and PR_LOCK_SHADOW_STACK_STATUS. As part of PR_SET_SHADOW_STACK_STATUS/PR_GET_SHADOW_STACK_STATUS, only PR_SHADOW_STACK_ENABLE is implemented because RISCV allows each mode to write to their own shadow stack using 'sspush' or 'ssamoswap'. PR_LOCK_SHADOW_STACK_STATUS locks the current shadow stack enablement configuration. Reviewed-by: Zong Li <zong.li@sifive.com> Signed-off-by: Deepak Gupta <debug@rivosinc.com> Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> # QEMU, custom CVA6 Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com> Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-12-b55691eacf4f@rivosinc.com [pjw@kernel.org: cleaned up patch description] Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-29riscv/shstk: If needed allocate a new shadow stack on cloneDeepak Gupta
Userspace specifies CLONE_VM to share address space and spawn new thread. 'clone' allows userspace to specify a new stack for a new thread. However there is no way to specify a new shadow stack base address without changing the API. This patch allocates a new shadow stack whenever CLONE_VM is given. In case of CLONE_VFORK, the parent is suspended until the child finishes; thus the child can use the parent's shadow stack. In case of !CLONE_VM, COW kicks in because entire address space is copied from parent to child. 'clone3' is extensible and can provide mechanisms for specifying the shadow stack as an input parameter. This is not settled yet and is being extensively discussed on the mailing list. Once that's settled, this code should be adapted. Reviewed-by: Zong Li <zong.li@sifive.com> Signed-off-by: Deepak Gupta <debug@rivosinc.com> Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> # QEMU, custom CVA6 Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com> Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-11-b55691eacf4f@rivosinc.com [pjw@kernel.org: cleaned up patch description] Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-29riscv: compat: fix COMPAT_UTS_MACHINE definitionHan Gao
The COMPAT_UTS_MACHINE for riscv was incorrectly defined as "riscv". Change it to "riscv32" to reflect the correct 32-bit compat name. Fixes: 06d0e3723647 ("riscv: compat: Add basic compat data type implementation") Cc: stable@vger.kernel.org Signed-off-by: Han Gao <gaohan@iscas.ac.cn> Reviewed-by: Guo Ren (Alibaba Damo Academy) <guoren@kernel.org> Link: https://patch.msgid.link/20260127190711.2264664-1-gaohan@iscas.ac.cn Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-26mm: provide address parameter to p{te,md,ud}_user_accessible_page()Rohan McLure
On several powerpc platforms, a page table entry may not imply whether the relevant mapping is for userspace or kernelspace. Instead, such platforms infer this by the address which is being accessed. Add an additional address argument to each of these routines in order to provide support for page table check on powerpc. [ajd@linux.ibm.com: rebase on arm64 changes] Link: https://lkml.kernel.org/r/20251219-pgtable_check_v18rebase-v18-9-755bc151a50b@linux.ibm.com Signed-off-by: Rohan McLure <rmclure@linux.ibm.com> Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com> Acked-by: Ingo Molnar <mingo@kernel.org> # x86 Acked-by: Alexandre Ghiti <alexghiti@rivosinc.com> # riscv Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Alistair Popple <apopple@nvidia.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: "Christophe Leroy (CS GROUP)" <chleroy@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Guo Weikang <guoweikang.kernel@gmail.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Magnus Lindholm <linmag7@gmail.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Miehlbradt <nicholas@linux.ibm.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com> Cc: Sweet Tea Dorminy <sweettea-kernel@dorminy.me> Cc: Thomas Huth <thuth@redhat.com> Cc: "Vishal Moola (Oracle)" <vishal.moola@gmail.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26mm/page_table_check: reinstate address parameter in ↵Rohan McLure
[__]page_table_check_pte_clear() This reverts commit aa232204c468 ("mm/page_table_check: remove unused parameter in [__]page_table_check_pte_clear"). Reinstate previously unused parameters for the purpose of supporting powerpc platforms, as many do not encode user/kernel ownership of the page in the pte, but instead in the address of the access. [ajd@linux.ibm.com: rebase, fix additional occurrence and loop handling] Link: https://lkml.kernel.org/r/20251219-pgtable_check_v18rebase-v18-8-755bc151a50b@linux.ibm.com Signed-off-by: Rohan McLure <rmclure@linux.ibm.com> Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com> Acked-by: Ingo Molnar <mingo@kernel.org> # x86 Acked-by: Alexandre Ghiti <alexghiti@rivosinc.com> # riscv Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Alistair Popple <apopple@nvidia.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: "Christophe Leroy (CS GROUP)" <chleroy@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Guo Weikang <guoweikang.kernel@gmail.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Magnus Lindholm <linmag7@gmail.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Miehlbradt <nicholas@linux.ibm.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com> Cc: Sweet Tea Dorminy <sweettea-kernel@dorminy.me> Cc: Thomas Huth <thuth@redhat.com> Cc: "Vishal Moola (Oracle)" <vishal.moola@gmail.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26mm/page_table_check: reinstate address parameter in ↵Rohan McLure
[__]page_table_check_pmd_clear() This reverts commit 1831414cd729 ("mm/page_table_check: remove unused parameter in [__]page_table_check_pmd_clear"). Reinstate previously unused parameters for the purpose of supporting powerpc platforms, as many do not encode user/kernel ownership of the page in the pte, but instead in the address of the access. [ajd@linux.ibm.com: rebase on arm64 changes] Link: https://lkml.kernel.org/r/20251219-pgtable_check_v18rebase-v18-7-755bc151a50b@linux.ibm.com Signed-off-by: Rohan McLure <rmclure@linux.ibm.com> Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com> Acked-by: Ingo Molnar <mingo@kernel.org> # x86 Acked-by: Alexandre Ghiti <alexghiti@rivosinc.com> # riscv Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Alistair Popple <apopple@nvidia.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: "Christophe Leroy (CS GROUP)" <chleroy@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Guo Weikang <guoweikang.kernel@gmail.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Magnus Lindholm <linmag7@gmail.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Miehlbradt <nicholas@linux.ibm.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com> Cc: Sweet Tea Dorminy <sweettea-kernel@dorminy.me> Cc: Thomas Huth <thuth@redhat.com> Cc: "Vishal Moola (Oracle)" <vishal.moola@gmail.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26mm/page_table_check: reinstate address parameter in ↵Rohan McLure
[__]page_table_check_pud_clear() This reverts commit 931c38e16499 ("mm/page_table_check: remove unused parameter in [__]page_table_check_pud_clear"). Reinstate previously unused parameters for the purpose of supporting powerpc platforms, as many do not encode user/kernel ownership of the page in the pte, but instead in the address of the access. [ajd@linux.ibm.com: rebase on arm64 changes] Link: https://lkml.kernel.org/r/20251219-pgtable_check_v18rebase-v18-6-755bc151a50b@linux.ibm.com Signed-off-by: Rohan McLure <rmclure@linux.ibm.com> Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com> Acked-by: Ingo Molnar <mingo@kernel.org> # x86 Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: "Christophe Leroy (CS GROUP)" <chleroy@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Guo Weikang <guoweikang.kernel@gmail.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Magnus Lindholm <linmag7@gmail.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Miehlbradt <nicholas@linux.ibm.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com> Cc: Sweet Tea Dorminy <sweettea-kernel@dorminy.me> Cc: Thomas Huth <thuth@redhat.com> Cc: "Vishal Moola (Oracle)" <vishal.moola@gmail.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26mm/page_table_check: provide addr parameter to page_table_check_ptes_set()Rohan McLure
To provide support for powerpc platforms, provide an addr parameter to the __page_table_check_ptes_set() and page_table_check_ptes_set() routines. This parameter is needed on some powerpc platforms which do not encode whether a mapping is for user or kernel in the pte. On such platforms, this can be inferred from the addr parameter. [ajd@linux.ibm.com: rebase on arm64 + riscv changes, update commit message] Link: https://lkml.kernel.org/r/20251219-pgtable_check_v18rebase-v18-5-755bc151a50b@linux.ibm.com Signed-off-by: Rohan McLure <rmclure@linux.ibm.com> Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com> Acked-by: Alexandre Ghiti <alexghiti@rivosinc.com> # riscv Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Alistair Popple <apopple@nvidia.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: "Christophe Leroy (CS GROUP)" <chleroy@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Guo Weikang <guoweikang.kernel@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Magnus Lindholm <linmag7@gmail.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Miehlbradt <nicholas@linux.ibm.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com> Cc: Sweet Tea Dorminy <sweettea-kernel@dorminy.me> Cc: Thomas Huth <thuth@redhat.com> Cc: "Vishal Moola (Oracle)" <vishal.moola@gmail.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26mm/page_table_check: reinstate address parameter in ↵Rohan McLure
[__]page_table_check_pmd[s]_set() This reverts commit a3b837130b58 ("mm/page_table_check: remove unused parameter in [__]page_table_check_pmd_set"). Reinstate previously unused parameters for the purpose of supporting powerpc platforms, as many do not encode user/kernel ownership of the page in the pte, but instead in the address of the access. Apply this to __page_table_check_pmds_set(), page_table_check_pmd_set(), and the page_table_check_pmd_set() wrapper macro. [ajd@linux.ibm.com: rebase on arm64 + riscv changes, update commit message] Link: https://lkml.kernel.org/r/20251219-pgtable_check_v18rebase-v18-4-755bc151a50b@linux.ibm.com Signed-off-by: Rohan McLure <rmclure@linux.ibm.com> Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com> Acked-by: Ingo Molnar <mingo@kernel.org> # x86 Acked-by: Alexandre Ghiti <alexghiti@rivosinc.com> # riscv Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Alistair Popple <apopple@nvidia.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: "Christophe Leroy (CS GROUP)" <chleroy@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Guo Weikang <guoweikang.kernel@gmail.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Magnus Lindholm <linmag7@gmail.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Miehlbradt <nicholas@linux.ibm.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com> Cc: Sweet Tea Dorminy <sweettea-kernel@dorminy.me> Cc: Thomas Huth <thuth@redhat.com> Cc: "Vishal Moola (Oracle)" <vishal.moola@gmail.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-26mm/page_table_check: reinstate address parameter in ↵Rohan McLure
[__]page_table_check_pud[s]_set() This reverts commit 6d144436d954 ("mm/page_table_check: remove unused parameter in [__]page_table_check_pud_set"). Reinstate previously unused parameters for the purpose of supporting powerpc platforms, as many do not encode user/kernel ownership of the page in the pte, but instead in the address of the access. Apply this to __page_table_check_puds_set(), page_table_check_puds_set() and the page_table_check_pud_set() wrapper macro. [ajd@linux.ibm.com: rebase on riscv + arm64 changes, update commit message] Link: https://lkml.kernel.org/r/20251219-pgtable_check_v18rebase-v18-3-755bc151a50b@linux.ibm.com Signed-off-by: Rohan McLure <rmclure@linux.ibm.com> Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com> Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com> Acked-by: Ingo Molnar <mingo@kernel.org> # x86 Acked-by: Alexandre Ghiti <alexghiti@rivosinc.com> # riscv Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Alistair Popple <apopple@nvidia.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: "Christophe Leroy (CS GROUP)" <chleroy@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Donet Tom <donettom@linux.ibm.com> Cc: Guo Weikang <guoweikang.kernel@gmail.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Magnus Lindholm <linmag7@gmail.com> Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Miehlbradt <nicholas@linux.ibm.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com> Cc: Sweet Tea Dorminy <sweettea-kernel@dorminy.me> Cc: Thomas Huth <thuth@redhat.com> Cc: "Vishal Moola (Oracle)" <vishal.moola@gmail.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-25riscv/mm: update write protect to work on shadow stacksDeepak Gupta
'fork' implements copy-on-write (COW) by making pages readonly in both child and parent. ptep_set_wrprotect() and pte_wrprotect() clear _PAGE_WRITE in PTE. The assumption is that the page is readable and, on a fault, copy-on-write happens. To implement COW on shadow stack pages, clearing the W bit makes them XWR = 000. This will result in the wrong PTE setting, which allows no permissions, but with V=1 and the PFN field pointing to the final page. Instead, the desired behavior is to turn it into a readable page, take an access (load/store) fault on sspush/sspop (shadow stack) and then perform COW on such pages. This way regular reads would still be allowed and not lead to COW maintaining current behavior of COW on non-shadow stack but writeable memory. On the other hand, this doesn't interfere with existing COW for read-write memory. The assumption is always that _PAGE_READ must have been set, and thus, setting _PAGE_READ is harmless. Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Reviewed-by: Zong Li <zong.li@sifive.com> Signed-off-by: Deepak Gupta <debug@rivosinc.com> Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> # QEMU, custom CVA6 Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com> Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-9-b55691eacf4f@rivosinc.com [pjw@kernel.org: clarify patch description] Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-25riscv/mm: teach pte_mkwrite to manufacture shadow stack PTEsDeepak Gupta
pte_mkwrite() creates PTEs with WRITE encodings for the underlying architecture. The underlying architecture can have two types of writeable mappings: one that can be written using regular store instructions, and another one that can only be written using specialized store instructions (like shadow stack stores). pte_mkwrite can select write PTE encoding based on VMA range (i.e. VM_SHADOW_STACK) Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Reviewed-by: Zong Li <zong.li@sifive.com> Signed-off-by: Deepak Gupta <debug@rivosinc.com> Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> # QEMU, custom CVA6 Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com> Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-8-b55691eacf4f@rivosinc.com [pjw@kernel.org: cleaned up patch description] Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-25riscv/mm: manufacture shadow stack ptesDeepak Gupta
This patch implements the creation of a shadow stack pte on riscv. Creating shadow stack PTE on riscv means clearing RWX and then setting W=1. Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Reviewed-by: Zong Li <zong.li@sifive.com> Signed-off-by: Deepak Gupta <debug@rivosinc.com> Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> # QEMU, custom CVA6 Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com> Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-7-b55691eacf4f@rivosinc.com [pjw@kernel.org: cleaned up patch description] Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-25riscv/mm: ensure PROT_WRITE leads to VM_READ | VM_WRITEDeepak Gupta
'arch_calc_vm_prot_bits' is implemented on risc-v to return VM_READ | VM_WRITE if PROT_WRITE is specified. Similarly 'riscv_sys_mmap' is updated to convert all incoming PROT_WRITE to (PROT_WRITE | PROT_READ). This is to make sure that any existing apps using PROT_WRITE still work. Earlier 'protection_map[VM_WRITE]' used to pick read-write PTE encodings. Now 'protection_map[VM_WRITE]' will always pick PAGE_SHADOWSTACK PTE encodings for shadow stack. The above changes ensure that existing apps continue to work because underneath, the kernel will be picking 'protection_map[VM_WRITE|VM_READ]' PTE encodings. Reviewed-by: Zong Li <zong.li@sifive.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Signed-off-by: Deepak Gupta <debug@rivosinc.com> Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> # QEMU, custom CVA6 Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com> Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-6-b55691eacf4f@rivosinc.com Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-25riscv: Add usercfi state for task and save/restore of CSR_SSP on trap entry/exitDeepak Gupta
Carve out space in the RISC-V architecture-specific thread struct for cfi status and shadow stack in usermode. This patch: - defines a new structure cfi_status with status bit for cfi feature - defines shadow stack pointer, base and size in cfi_status structure - defines offsets to new member fields in thread in asm-offsets.c - saves and restores shadow stack pointer on trap entry (U --> S) and exit (S --> U) Shadow stack save/restore is gated on feature availability and is implemented using alternatives. CSR_SSP can be context-switched in 'switch_to' as well, but as soon as kernel shadow stack support gets rolled in, the shadow stack pointer will need to be switched at trap entry/exit point (much like 'sp'). It can be argued that a kernel using a shadow stack deployment scenario may not be as prevalent as user mode using this feature. But even if there is some minimal deployment of kernel shadow stack, that means that it needs to be supported. Thus save/restore of shadow stack pointer is implemented in entry.S instead of in 'switch_to.h'. Reviewed-by: Charlie Jenkins <charlie@rivosinc.com> Reviewed-by: Zong Li <zong.li@sifive.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Signed-off-by: Deepak Gupta <debug@rivosinc.com> Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> # QEMU, custom CVA6 Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com> Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-5-b55691eacf4f@rivosinc.com [pjw@kernel.org: cleaned up patch description] Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-25riscv: add Zicfiss / Zicfilp extension CSR and bit definitionsDeepak Gupta
The Zicfiss and Zicfilp extensions are enabled via b3 and b2 in *envcfg CSRs. menvcfg controls enabling for S/HS mode. henvcfg controls enabling for VS. senvcfg controls enabling for U/VU mode. The Zicfilp extension extends *status CSRs to hold an 'expected landing pad' bit. A trap or interrupt can occur between an indirect jmp/call and target instruction. The 'expected landing pad' bit from the CPU is recorded into the xstatus CSR so that when the supervisor performs xret, the 'expected landing pad' state of the CPU can be restored. Zicfiss adds one new CSR, CSR_SSP, which contains the current shadow stack pointer. Signed-off-by: Deepak Gupta <debug@rivosinc.com> Reviewed-by: Charlie Jenkins <charlie@rivosinc.com> Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> # QEMU, custom CVA6 Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com> Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-4-b55691eacf4f@rivosinc.com [pjw@kernel.org: grouped CSR_SSP macro with the other CSR macros; clarified patch description] Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-25riscv: zicfiss / zicfilp enumerationDeepak Gupta
This patch adds support for detecting the RISC-V ISA extensions Zicfiss and Zicfilp. Zicfiss and Zicfilp stand for the unprivileged integer spec extensions for shadow stack and indirect branch tracking, respectively. This patch looks for Zicfiss and Zicfilp in the device tree and accordingly lights up the corresponding bits in the cpu feature bitmap. Furthermore this patch adds detection utility functions to return whether shadow stack or landing pads are supported by the cpu. Reviewed-by: Zong Li <zong.li@sifive.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Signed-off-by: Deepak Gupta <debug@rivosinc.com> Tested-by: Andreas Korb <andreas.korb@aisec.fraunhofer.de> # QEMU, custom CVA6 Tested-by: Valentin Haudiquet <valentin.haudiquet@canonical.com> Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-3-b55691eacf4f@rivosinc.com [pjw@kernel.org: updated to apply; cleaned up patch description] Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-25riscv: mm: define copy_user_page() as copy_page()Florian Schmaus
Currently, the implementation of copy_user_page() is identical to copy_page(). Align riscv with other architectures (alpha, arc, arm64, hexagon, longarch, m68k, openrisc, s390, um, xtensa) and map copy_user_page() to copy_page() given that their implementation is identical. In addition to following a common pattern, this centralizes the implementation. Any changes to the underlying page copy logic (e.g., for CHERI) will now automatically propagate to copy_user_page(). Signed-off-by: Florian Schmaus <florian.schmaus@codasip.com> Link: https://patch.msgid.link/20260113134025.905627-1-florian.schmaus@codasip.com Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-25riscv: fix minor typo in syscall.h commentAustin Kim
Some developers may be confused because RISC-V does not have a register named r0. Also, orig_r0 is not available in pt_regs structure, which is specific to riscv. So we had better fix this minor typo. Signed-off-by: Austin Kim <austin.kim@lge.com> Link: https://patch.msgid.link/aW3Z4zTBvGJpk7a7@adminpc-PowerEdge-R7525 Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-22riscv: Add intermediate cast to 'unsigned long' in __get_user_asmNathan Chancellor
After commit bdce162f2e57 ("riscv: Use 64-bit variable for output in __get_user_asm"), there is a warning when building for 32-bit RISC-V: In file included from include/linux/uaccess.h:13, from include/linux/sched/task.h:13, from include/linux/sched/signal.h:9, from include/linux/rcuwait.h:6, from include/linux/mm.h:36, from include/linux/migrate.h:5, from mm/migrate.c:16: mm/migrate.c: In function 'do_pages_move': arch/riscv/include/asm/uaccess.h:115:15: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast] 115 | (x) = (__typeof__(x))__tmp; \ | ^ arch/riscv/include/asm/uaccess.h:198:17: note: in expansion of macro '__get_user_asm' 198 | __get_user_asm("lb", (x), __gu_ptr, label); \ | ^~~~~~~~~~~~~~ arch/riscv/include/asm/uaccess.h:218:9: note: in expansion of macro '__get_user_nocheck' 218 | __get_user_nocheck(x, ptr, __gu_failed); \ | ^~~~~~~~~~~~~~~~~~ arch/riscv/include/asm/uaccess.h:255:9: note: in expansion of macro '__get_user_error' 255 | __get_user_error(__gu_val, __gu_ptr, __gu_err); \ | ^~~~~~~~~~~~~~~~ arch/riscv/include/asm/uaccess.h:285:17: note: in expansion of macro '__get_user' 285 | __get_user((x), __p) : \ | ^~~~~~~~~~ mm/migrate.c:2358:29: note: in expansion of macro 'get_user' 2358 | if (get_user(p, pages + i)) | ^~~~~~~~ Add an intermediate cast to 'unsigned long', which is guaranteed to be the same width as a pointer, before the cast to the type of the output variable to clear up the warning. Fixes: bdce162f2e57 ("riscv: Use 64-bit variable for output in __get_user_asm") Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202601210526.OT45dlOZ-lkp@intel.com/ Signed-off-by: Nathan Chancellor <nathan@kernel.org> Link: https://patch.msgid.link/20260121-riscv-fix-int-to-pointer-cast-v1-1-b83eebe57c76@kernel.org Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-20treewide: provide a generic clear_user_page() variantDavid Hildenbrand
Patch series "mm: folio_zero_user: clear page ranges", v11. This series adds clearing of contiguous page ranges for hugepages. The series improves on the current discontiguous clearing approach in two ways: - clear pages in a contiguous fashion. - use batched clearing via clear_pages() wherever exposed. The first is useful because it allows us to make much better use of hardware prefetchers. The second, enables advertising the real extent to the processor. Where specific instructions support it (ex. string instructions on x86; "mops" on arm64 etc), a processor can optimize based on this because, instead of seeing a sequence of 8-byte stores, or a sequence of 4KB pages, it sees a larger unit being operated on. For instance, AMD Zen uarchs (for extents larger than LLC-size) switch to a mode where they start eliding cacheline allocation. This is helpful not just because it results in higher bandwidth, but also because now the cache is not evicting useful cachelines and replacing them with zeroes. Demand faulting a 64GB region shows performance improvement: $ perf bench mem mmap -p $pg-sz -f demand -s 64GB -l 5 baseline +series (GBps +- %stdev) (GBps +- %stdev) pg-sz=2MB 11.76 +- 1.10% 25.34 +- 1.18% [*] +115.47% preempt=* pg-sz=1GB 24.85 +- 2.41% 39.22 +- 2.32% + 57.82% preempt=none|voluntary pg-sz=1GB (similar) 52.73 +- 0.20% [#] +112.19% preempt=full|lazy [*] This improvement is because switching to sequential clearing allows the hardware prefetchers to do a much better job. [#] For pg-sz=1GB a large part of the improvement is because of the cacheline elision mentioned above. preempt=full|lazy improves upon that because, not needing explicit invocations of cond_resched() to ensure reasonable preemption latency, it can clear the full extent as a single unit. In comparison the maximum extent used for preempt=none|voluntary is PROCESS_PAGES_NON_PREEMPT_BATCH (32MB). When provided the full extent the processor forgoes allocating cachelines on this path almost entirely. (The hope is that eventually, in the fullness of time, the lazy preemption model will be able to do the same job that none or voluntary models are used for, allowing us to do away with cond_resched().) Raghavendra also tested previous version of the series on AMD Genoa and sees similar improvement [1] with preempt=lazy. $ perf bench mem map -p $page-size -f populate -s 64GB -l 10 base patched change pg-sz=2MB 12.731939 GB/sec 26.304263 GB/sec 106.6% pg-sz=1GB 26.232423 GB/sec 61.174836 GB/sec 133.2% This patch (of 8): Let's drop all variants that effectively map to clear_page() and provide it in a generic variant instead. We'll use the macro clear_user_page to indicate whether an architecture provides it's own variant. Also, clear_user_page() is only called from the generic variant of clear_user_highpage(), so define it only if the architecture does not provide a clear_user_highpage(). And, for simplicity define it in linux/highmem.h. Note that for parisc, clear_page() and clear_user_page() map to clear_page_asm(), so we can just get rid of the custom clear_user_page() implementation. There is a clear_user_page_asm() function on parisc, that seems to be unused. Not sure what's up with that. Link: https://lkml.kernel.org/r/20260107072009.1615991-1-ankur.a.arora@oracle.com Link: https://lkml.kernel.org/r/20260107072009.1615991-2-ankur.a.arora@oracle.com Signed-off-by: David Hildenbrand <david@redhat.com> Co-developed-by: Ankur Arora <ankur.a.arora@oracle.com> Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ankur Arora <ankur.a.arora@oracle.com> Cc: "Borislav Petkov (AMD)" <bp@alien8.de> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Hildenbrand <david@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Konrad Rzessutek Wilk <konrad.wilk@oracle.com> Cc: Lance Yang <ioworker0@gmail.com> Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com> Cc: Li Zhe <lizhe.67@bytedance.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Mateusz Guzik <mjguzik@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Raghavendra K T <raghavendra.kt@amd.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-16riscv: Use 64-bit variable for output in __get_user_asmNathan Chancellor
After commit f6bff7827a48 ("riscv: uaccess: use 'asm_goto_output' for get_user()"), which was the first commit that started using asm goto with outputs on RISC-V, builds of clang built with assertions enabled start crashing in certain files that use get_user() with: clang: llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp:12743: Register FollowCopyChain(MachineRegisterInfo &, Register): Assertion `MI->getOpcode() == TargetOpcode::COPY && "start of copy chain MUST be COPY"' failed. Internally, LLVM generates an addiw instruction when the output of the inline asm (which may be any scalar type) needs to be sign extended for ABI reasons, such as a later function call, so that basic block does not have to do it. Use a temporary 64-bit variable as the output of the inline assembly in __get_user_asm() and explicitly cast it to truncate it if necessary, avoiding the addiw that triggers the assertion. Link: https://github.com/ClangBuiltLinux/linux/issues/2092 Signed-off-by: Nathan Chancellor <nathan@kernel.org> Link: https://patch.msgid.link/20260116-riscv-wa-llvm-asm-goto-outputs-assertion-failure-v3-1-55b5775f989b@kernel.org Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-12riscv/paravirt: Use common code for paravirt_steal_clock()Juergen Gross
Remove the arch specific variant of paravirt_steal_clock() and use the common one instead. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20260105110520.21356-11-jgross@suse.com
2026-01-12sched: Move clock related paravirt code to kernel/schedJuergen Gross
Paravirt clock related functions are available in multiple archs. In order to share the common parts, move the common static keys to kernel/sched/ and remove them from the arch specific files. Make a common paravirt_steal_clock() implementation available in kernel/sched/cputime.c, guarding it with a new config option CONFIG_HAVE_PV_STEAL_CLOCK_GEN, which can be selected by an arch in case it wants to use that common variant. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20260105110520.21356-7-jgross@suse.com
2026-01-12paravirt: Remove asm/paravirt_api_clock.hJuergen Gross
All architectures supporting CONFIG_PARAVIRT share the same contents of asm/paravirt_api_clock.h: #include <asm/paravirt.h> So remove all incarnations of asm/paravirt_api_clock.h and remove the only place where it is included, as there asm/paravirt.h is included anyway. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shrikanth Hegde <sshegde@linux.ibm.com> # powerpc, scheduler bits Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://patch.msgid.link/20260105110520.21356-6-jgross@suse.com
2026-01-07riscv: remove irqflags.h inclusion in asm/bitops.hYunhui Cui
The arch/riscv/include/asm/bitops.h does not functionally require including /linux/irqflags.h. Additionally, adding arch/riscv/include/asm/percpu.h causes a circular inclusion: kernel/bounds.c ->include/linux/log2.h ->include/linux/bitops.h ->arch/riscv/include/asm/bitops.h ->include/linux/irqflags.h ->include/linux/find.h ->return val ? __ffs(val) : size; ->arch/riscv/include/asm/bitops.h The compilation log is as follows: CC kernel/bounds.s In file included from ./include/linux/bitmap.h:11, from ./include/linux/cpumask.h:12, from ./arch/riscv/include/asm/processor.h:55, from ./arch/riscv/include/asm/thread_info.h:42, from ./include/linux/thread_info.h:60, from ./include/asm-generic/preempt.h:5, from ./arch/riscv/include/generated/asm/preempt.h:1, from ./include/linux/preempt.h:79, from ./arch/riscv/include/asm/percpu.h:8, from ./include/linux/irqflags.h:19, from ./arch/riscv/include/asm/bitops.h:14, from ./include/linux/bitops.h:68, from ./include/linux/log2.h:12, from kernel/bounds.c:13: ./include/linux/find.h: In function 'find_next_bit': ./include/linux/find.h:66:30: error: implicit declaration of function '__ffs' [-Wimplicit-function-declaration] 66 | return val ? __ffs(val) : size; | ^~~~~ Signed-off-by: Yunhui Cui <cuiyunhui@bytedance.com> Acked-by: Yury Norov (NVIDIA) <yury.norov@gmail.com> Link: https://patch.msgid.link/20251216014721.42262-2-cuiyunhui@bytedance.com Signed-off-by: Paul Walmsley <pjw@kernel.org>
2026-01-05riscv: pgtable: Cleanup useless VA_USER_XXX definitionsGuo Ren (Alibaba DAMO Academy)
These marcos are not used after commit b5b4287accd7 ("riscv: mm: Use hint address in mmap if available"). Cleanup VA_USER_XXX definitions in asm/pgtable.h. Fixes: b5b4287accd7 ("riscv: mm: Use hint address in mmap if available") Signed-off-by: Guo Ren (Alibaba DAMO Academy) <guoren@kernel.org> Reviewed-by: Jinjie Ruan <ruanjinjie@huawei.com> Link: https://patch.msgid.link/20251201005850.702569-1-guoren@kernel.org Signed-off-by: Paul Walmsley <pjw@kernel.org>
2025-12-19riscv: Add SBI debug trigger extension and function idsHimanshu Chauhan
Debug trigger extension is an SBI extension to support native debugging in S-mode and VS-mode. This patch adds the extension and the function IDs defined by the extension. Signed-off-by: Himanshu Chauhan <hchauhan@ventanamicro.com> Link: https://patch.msgid.link/20250710125231.653967-2-hchauhan@ventanamicro.com [pjw@kernel.org: updated to apply] Signed-off-by: Paul Walmsley <pjw@kernel.org>
2025-12-19riscv/atomic.h: use RISCV_FULL_BARRIER in _arch_atomic* function.Zongmin Zhou
Replace the same code with the pre-defined macro RISCV_FULL_BARRIER to simplify the code. Signed-off-by: Zongmin Zhou <zhouzongmin@kylinos.cn> Link: https://patch.msgid.link/20251120095831.64211-1-min_halo@163.com Signed-off-by: Paul Walmsley <pjw@kernel.org>
2025-12-19riscv: add ISA extension parsing for Zilsd and ZclsdPincheng Wang
Add parsing for Zilsd and Zclsd ISA extensions which were ratified in commit f88abf1 ("Integrating load/store pair for RV32 with the main manual") of the riscv-isa-manual. Signed-off-by: Pincheng Wang <pincheng.plct@isrc.iscas.ac.cn> Reviewed-by: Nutty Liu <nutty.liu@hotmail.com> Link: https://patch.msgid.link/20250826162939.1494021-3-pincheng.plct@isrc.iscas.ac.cn [pjw@kernel.org: cleaned up checkpatch issues, whitespace; updated to apply] Signed-off-by: Paul Walmsley <pjw@kernel.org>
2025-12-19riscv: mm: use xchg() on non-atomic_long_t variables, not atomic_long_xchg()Paul Walmsley
Let's not call atomic_long_xchg() on something that's not an atomic_long_t, and just use xchg() instead. Continues the cleanup from commit 546e42c8c6d94 ("riscv: Use an atomic xchg in pudp_huge_get_and_clear()"), Cc: Alexandre Ghiti <alex@ghiti.fr> Signed-off-by: Paul Walmsley <pjw@kernel.org>
2025-12-19riscv: mm: ptep_get_and_clear(): avoid atomic ops when !CONFIG_SMPPaul Walmsley
When !CONFIG_SMP, there's no need for atomic operations in ptep_get_and_clear(), so, similar to x86, let's not use atomics in this case. Cc: Alexandre Ghiti <alex@ghiti.fr> Signed-off-by: Paul Walmsley <pjw@kernel.org>
2025-12-19riscv: mm: pmdp_huge_get_and_clear(): avoid atomic ops when !CONFIG_SMPPaul Walmsley
When !CONFIG_SMP, there's no need for atomic operations in pmdp_huge_get_and_clear(), so, similar to what x86 does, let's not use atomics in this case. See also commit 546e42c8c6d94 ("riscv: Use an atomic xchg in pudp_huge_get_and_clear()"). Cc: Alexandre Ghiti <alex@ghiti.fr> Signed-off-by: Paul Walmsley <pjw@kernel.org>
2025-12-19riscv: signal: abstract header saving for setup_sigcontextAndy Chiu
The function save_v_state() served two purposes. First, it saved extension context into the signal stack. Then, it constructed the extension header if there was no fault. The second part is independent of the extension itself. As a result, we can pull that part out, so future extensions may reuse it. This patch adds arch_ext_list and makes setup_sigcontext() go through all possible extensions' save() callback. The callback returns a positive value indicating the size of the successfully saved extension. Then the kernel proceeds to construct the header for that extension. The kernel skips an extension if it does not exist, or if the saving fails for some reasons. The error code is propagated out on the later case. This patch does not introduce any functional changes. Signed-off-by: Andy Chiu <andybnac@gmail.com> Link: https://patch.msgid.link/20251112-v5_user_cfi_series-v23-16-b55691eacf4f@rivosinc.com Signed-off-by: Paul Walmsley <pjw@kernel.org>
2025-12-05Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Paolo Bonzini: "ARM: - Support for userspace handling of synchronous external aborts (SEAs), allowing the VMM to potentially handle the abort in a non-fatal manner - Large rework of the VGIC's list register handling with the goal of supporting more active/pending IRQs than available list registers in hardware. In addition, the VGIC now supports EOImode==1 style deactivations for IRQs which may occur on a separate vCPU than the one that acked the IRQ - Support for FEAT_XNX (user / privileged execute permissions) and FEAT_HAF (hardware update to the Access Flag) in the software page table walkers and shadow MMU - Allow page table destruction to reschedule, fixing long need_resched latencies observed when destroying a large VM - Minor fixes to KVM and selftests Loongarch: - Get VM PMU capability from HW GCFG register - Add AVEC basic support - Use 64-bit register definition for EIOINTC - Add KVM timer test cases for tools/selftests RISC/V: - SBI message passing (MPXY) support for KVM guest - Give a new, more specific error subcode for the case when in-kernel AIA virtualization fails to allocate IMSIC VS-file - Support KVM_DIRTY_LOG_INITIALLY_SET, enabling dirty log gradually in small chunks - Fix guest page fault within HLV* instructions - Flush VS-stage TLB after VCPU migration for Andes cores s390: - Always allocate ESCA (Extended System Control Area), instead of starting with the basic SCA and converting to ESCA with the addition of the 65th vCPU. The price is increased number of exits (and worse performance) on z10 and earlier processor; ESCA was introduced by z114/z196 in 2010 - VIRT_XFER_TO_GUEST_WORK support - Operation exception forwarding support - Cleanups x86: - Skip the costly "zap all SPTEs" on an MMIO generation wrap if MMIO SPTE caching is disabled, as there can't be any relevant SPTEs to zap - Relocate a misplaced export - Fix an async #PF bug where KVM would clear the completion queue when the guest transitioned in and out of paging mode, e.g. when handling an SMI and then returning to paged mode via RSM - Leave KVM's user-return notifier registered even when disabling virtualization, as long as kvm.ko is loaded. On reboot/shutdown, keeping the notifier registered is ok; the kernel does not use the MSRs and the callback will run cleanly and restore host MSRs if the CPU manages to return to userspace before the system goes down - Use the checked version of {get,put}_user() - Fix a long-lurking bug where KVM's lack of catch-up logic for periodic APIC timers can result in a hard lockup in the host - Revert the periodic kvmclock sync logic now that KVM doesn't use a clocksource that's subject to NTP corrections - Clean up KVM's handling of MMIO Stale Data and L1TF, and bury the latter behind CONFIG_CPU_MITIGATIONS - Context switch XCR0, XSS, and PKRU outside of the entry/exit fast path; the only reason they were handled in the fast path was to paper of a bug in the core #MC code, and that has long since been fixed - Add emulator support for AVX MOV instructions, to play nice with emulated devices whose guest drivers like to access PCI BARs with large multi-byte instructions x86 (AMD): - Fix a few missing "VMCB dirty" bugs - Fix the worst of KVM's lack of EFER.LMSLE emulation - Add AVIC support for addressing 4k vCPUs in x2AVIC mode - Fix incorrect handling of selective CR0 writes when checking intercepts during emulation of L2 instructions - Fix a currently-benign bug where KVM would clobber SPEC_CTRL[63:32] on VMRUN and #VMEXIT - Fix a bug where KVM corrupt the guest code stream when re-injecting a soft interrupt if the guest patched the underlying code after the VM-Exit, e.g. when Linux patches code with a temporary INT3 - Add KVM_X86_SNP_POLICY_BITS to advertise supported SNP policy bits to userspace, and extend KVM "support" to all policy bits that don't require any actual support from KVM x86 (Intel): - Use the root role from kvm_mmu_page to construct EPTPs instead of the current vCPU state, partly as worthwhile cleanup, but mostly to pave the way for tracking per-root TLB flushes, and elide EPT flushes on pCPU migration if the root is clean from a previous flush - Add a few missing nested consistency checks - Rip out support for doing "early" consistency checks via hardware as the functionality hasn't been used in years and is no longer useful in general; replace it with an off-by-default module param to WARN if hardware fails a check that KVM does not perform - Fix a currently-benign bug where KVM would drop the guest's SPEC_CTRL[63:32] on VM-Enter - Misc cleanups - Overhaul the TDX code to address systemic races where KVM (acting on behalf of userspace) could inadvertantly trigger lock contention in the TDX-Module; KVM was either working around these in weird, ugly ways, or was simply oblivious to them (though even Yan's devilish selftests could only break individual VMs, not the host kernel) - Fix a bug where KVM could corrupt a vCPU's cpu_list when freeing a TDX vCPU, if creating said vCPU failed partway through - Fix a few sparse warnings (bad annotation, 0 != NULL) - Use struct_size() to simplify copying TDX capabilities to userspace - Fix a bug where TDX would effectively corrupt user-return MSR values if the TDX Module rejects VP.ENTER and thus doesn't clobber host MSRs as expected Selftests: - Fix a math goof in mmu_stress_test when running on a single-CPU system/VM - Forcefully override ARCH from x86_64 to x86 to play nice with specifying ARCH=x86_64 on the command line - Extend a bunch of nested VMX to validate nested SVM as well - Add support for LA57 in the core VM_MODE_xxx macro, and add a test to verify KVM can save/restore nested VMX state when L1 is using 5-level paging, but L2 is not - Clean up the guest paging code in anticipation of sharing the core logic for nested EPT and nested NPT guest_memfd: - Add NUMA mempolicy support for guest_memfd, and clean up a variety of rough edges in guest_memfd along the way - Define a CLASS to automatically handle get+put when grabbing a guest_memfd from a memslot to make it harder to leak references - Enhance KVM selftests to make it easer to develop and debug selftests like those added for guest_memfd NUMA support, e.g. where test and/or KVM bugs often result in hard-to-debug SIGBUS errors - Misc cleanups Generic: - Use the recently-added WQ_PERCPU when creating the per-CPU workqueue for irqfd cleanup - Fix a goof in the dirty ring documentation - Fix choice of target for directed yield across different calls to kvm_vcpu_on_spin(); the function was always starting from the first vCPU instead of continuing the round-robin search" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (260 commits) KVM: arm64: at: Update AF on software walk only if VM has FEAT_HAFDBS KVM: arm64: at: Use correct HA bit in TCR_EL2 when regime is EL2 KVM: arm64: Document KVM_PGTABLE_PROT_{UX,PX} KVM: arm64: Fix spelling mistake "Unexpeced" -> "Unexpected" KVM: arm64: Add break to default case in kvm_pgtable_stage2_pte_prot() KVM: arm64: Add endian casting to kvm_swap_s[12]_desc() KVM: arm64: Fix compilation when CONFIG_ARM64_USE_LSE_ATOMICS=n KVM: arm64: selftests: Add test for AT emulation KVM: arm64: nv: Expose hardware access flag management to NV guests KVM: arm64: nv: Implement HW access flag management in stage-2 SW PTW KVM: arm64: Implement HW access flag management in stage-1 SW PTW KVM: arm64: Propagate PTW errors up to AT emulation KVM: arm64: Add helper for swapping guest descriptor KVM: arm64: nv: Use pgtable definitions in stage-2 walk KVM: arm64: Handle endianness in read helper for emulated PTW KVM: arm64: nv: Stop passing vCPU through void ptr in S2 PTW KVM: arm64: Call helper for reading descriptors directly KVM: arm64: nv: Advertise support for FEAT_XNX KVM: arm64: Teach ptdump about FEAT_XNX permissions KVM: s390: Use generic VIRT_XFER_TO_GUEST_WORK functions ...
2025-12-05Merge tag 'riscv-for-linus-6.19-mw1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Paul Walmsley: - Enable parallel hotplug for RISC-V - Optimize vector regset allocation for ptrace() - Add a kernel selftest for the vector ptrace interface - Enable the userspace RAID6 test to build and run using RISC-V vectors - Add initial support for the Zalasr RISC-V ratified ISA extension - For the Zicbop RISC-V ratified ISA extension to userspace, expose hardware and kernel support to userspace and add a kselftest for Zicbop - Convert open-coded instances of 'asm goto's that are controlled by runtime ALTERNATIVEs to use riscv_has_extension_{un,}likely(), following arm64's alternative_has_cap_{un,}likely() - Remove an unnecessary mask in the GFP flags used in some calls to pagetable_alloc() * tag 'riscv-for-linus-6.19-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: selftests/riscv: Add Zicbop prefetch test riscv: hwprobe: Expose Zicbop extension and its block size riscv: Introduce Zalasr instructions riscv: hwprobe: Export Zalasr extension dt-bindings: riscv: Add Zalasr ISA extension description riscv: Add ISA extension parsing for Zalasr selftests: riscv: Add test for the Vector ptrace interface riscv: ptrace: Optimize the allocation of vector regset raid6: test: Add support for RISC-V raid6: riscv: Allow code to be compiled in userspace raid6: riscv: Prevent compiler from breaking inline vector assembly code riscv: cmpxchg: Use riscv_has_extension_likely riscv: bitops: Use riscv_has_extension_likely riscv: hweight: Use riscv_has_extension_likely riscv: checksum: Use riscv_has_extension_likely riscv: pgtable: Use riscv_has_extension_unlikely riscv: Remove __GFP_HIGHMEM masking RISC-V: Enable HOTPLUG_PARALLEL for secondary CPUs
2025-12-05Merge tag 'mm-stable-2025-12-03-21-26' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "__vmalloc()/kvmalloc() and no-block support" (Uladzislau Rezki) Rework the vmalloc() code to support non-blocking allocations (GFP_ATOIC, GFP_NOWAIT) "ksm: fix exec/fork inheritance" (xu xin) Fix a rare case where the KSM MMF_VM_MERGE_ANY prctl state is not inherited across fork/exec "mm/zswap: misc cleanup of code and documentations" (SeongJae Park) Some light maintenance work on the zswap code "mm/page_owner: add debugfs files 'show_handles' and 'show_stacks_handles'" (Mauricio Faria de Oliveira) Enhance the /sys/kernel/debug/page_owner debug feature by adding unique identifiers to differentiate the various stack traces so that userspace monitoring tools can better match stack traces over time "mm/page_alloc: pcp->batch cleanups" (Joshua Hahn) Minor alterations to the page allocator's per-cpu-pages feature "Improve UFFDIO_MOVE scalability by removing anon_vma lock" (Lokesh Gidra) Address a scalability issue in userfaultfd's UFFDIO_MOVE operation "kasan: cleanups for kasan_enabled() checks" (Sabyrzhan Tasbolatov) "drivers/base/node: fold node register and unregister functions" (Donet Tom) Clean up the NUMA node handling code a little "mm: some optimizations for prot numa" (Kefeng Wang) Cleanups and small optimizations to the NUMA allocation hinting code "mm/page_alloc: Batch callers of free_pcppages_bulk" (Joshua Hahn) Address long lock hold times at boot on large machines. These were causing (harmless) softlockup warnings "optimize the logic for handling dirty file folios during reclaim" (Baolin Wang) Remove some now-unnecessary work from page reclaim "mm/damon: allow DAMOS auto-tuned for per-memcg per-node memory usage" (SeongJae Park) Enhance the DAMOS auto-tuning feature "mm/damon: fixes for address alignment issues in DAMON_LRU_SORT and DAMON_RECLAIM" (Quanmin Yan) Fix DAMON_LRU_SORT and DAMON_RECLAIM with certain userspace configuration "expand mmap_prepare functionality, port more users" (Lorenzo Stoakes) Enhance the new(ish) file_operations.mmap_prepare() method and port additional callsites from the old ->mmap() over to ->mmap_prepare() "Fix stale IOTLB entries for kernel address space" (Lu Baolu) Fix a bug (and possible security issue on non-x86) in the IOMMU code. In some situations the IOMMU could be left hanging onto a stale kernel pagetable entry "mm/huge_memory: cleanup __split_unmapped_folio()" (Wei Yang) Clean up and optimize the folio splitting code "mm, swap: misc cleanup and bugfix" (Kairui Song) Some cleanups and a minor fix in the swap discard code "mm/damon: misc documentation fixups" (SeongJae Park) "mm/damon: support pin-point targets removal" (SeongJae Park) Permit userspace to remove a specific monitoring target in the middle of the current targets list "mm: MISC follow-up patches for linux/pgalloc.h" (Harry Yoo) A couple of cleanups related to mm header file inclusion "mm/swapfile.c: select swap devices of default priority round robin" (Baoquan He) improve the selection of swap devices for NUMA machines "mm: Convert memory block states (MEM_*) macros to enums" (Israel Batista) Change the memory block labels from macros to enums so they will appear in kernel debug info "ksm: perform a range-walk to jump over holes in break_ksm" (Pedro Demarchi Gomes) Address an inefficiency when KSM unmerges an address range "mm/damon/tests: fix memory bugs in kunit tests" (SeongJae Park) Fix leaks and unhandled malloc() failures in DAMON userspace unit tests "some cleanups for pageout()" (Baolin Wang) Clean up a couple of minor things in the page scanner's writeback-for-eviction code "mm/hugetlb: refactor sysfs/sysctl interfaces" (Hui Zhu) Move hugetlb's sysfs/sysctl handling code into a new file "introduce VM_MAYBE_GUARD and make it sticky" (Lorenzo Stoakes) Make the VMA guard regions available in /proc/pid/smaps and improves the mergeability of guarded VMAs "mm: perform guard region install/remove under VMA lock" (Lorenzo Stoakes) Reduce mmap lock contention for callers performing VMA guard region operations "vma_start_write_killable" (Matthew Wilcox) Start work on permitting applications to be killed when they are waiting on a read_lock on the VMA lock "mm/damon/tests: add more tests for online parameters commit" (SeongJae Park) Add additional userspace testing of DAMON's "commit" feature "mm/damon: misc cleanups" (SeongJae Park) "make VM_SOFTDIRTY a sticky VMA flag" (Lorenzo Stoakes) Address the possible loss of a VMA's VM_SOFTDIRTY flag when that VMA is merged with another "mm: support device-private THP" (Balbir Singh) Introduce support for Transparent Huge Page (THP) migration in zone device-private memory "Optimize folio split in memory failure" (Zi Yan) "mm/huge_memory: Define split_type and consolidate split support checks" (Wei Yang) Some more cleanups in the folio splitting code "mm: remove is_swap_[pte, pmd]() + non-swap entries, introduce leaf entries" (Lorenzo Stoakes) Clean up our handling of pagetable leaf entries by introducing the concept of 'software leaf entries', of type softleaf_t "reparent the THP split queue" (Muchun Song) Reparent the THP split queue to its parent memcg. This is in preparation for addressing the long-standing "dying memcg" problem, wherein dead memcg's linger for too long, consuming memory resources "unify PMD scan results and remove redundant cleanup" (Wei Yang) A little cleanup in the hugepage collapse code "zram: introduce writeback bio batching" (Sergey Senozhatsky) Improve zram writeback efficiency by introducing batched bio writeback support "memcg: cleanup the memcg stats interfaces" (Shakeel Butt) Clean up our handling of the interrupt safety of some memcg stats "make vmalloc gfp flags usage more apparent" (Vishal Moola) Clean up vmalloc's handling of incoming GFP flags "mm: Add soft-dirty and uffd-wp support for RISC-V" (Chunyan Zhang) Teach soft dirty and userfaultfd write protect tracking to use RISC-V's Svrsw60t59b extension "mm: swap: small fixes and comment cleanups" (Youngjun Park) Fix a small bug and clean up some of the swap code "initial work on making VMA flags a bitmap" (Lorenzo Stoakes) Start work on converting the vma struct's flags to a bitmap, so we stop running out of them, especially on 32-bit "mm/swapfile: fix and cleanup swap list iterations" (Youngjun Park) Address a possible bug in the swap discard code and clean things up a little [ This merge also reverts commit ebb9aeb980e5 ("vfio/nvgrace-gpu: register device memory for poison handling") because it looks broken to me, I've asked for clarification - Linus ] * tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits) mm: fix vma_start_write_killable() signal handling mm/swapfile: use plist_for_each_entry in __folio_throttle_swaprate mm/swapfile: fix list iteration when next node is removed during discard fs/proc/task_mmu.c: fix make_uffd_wp_huge_pte() huge pte handling mm/kfence: add reboot notifier to disable KFENCE on shutdown memcg: remove inc/dec_lruvec_kmem_state helpers selftests/mm/uffd: initialize char variable to Null mm: fix DEBUG_RODATA_TEST indentation in Kconfig mm: introduce VMA flags bitmap type tools/testing/vma: eliminate dependency on vma->__vm_flags mm: simplify and rename mm flags function for clarity mm: declare VMA flags by bit zram: fix a spelling mistake mm/page_alloc: optimize lowmem_reserve max lookup using its semantic monotonicity mm/vmscan: skip increasing kswapd_failures when reclaim was boosted pagemap: update BUDDY flag documentation mm: swap: remove scan_swap_map_slots() references from comments mm: swap: change swap_alloc_slow() to void mm, swap: remove redundant comment for read_swap_cache_async mm, swap: use SWP_SOLIDSTATE to determine if swap is rotational ...
2025-12-02Merge tag 'core-uaccess-2025-11-30' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scoped user access updates from Thomas Gleixner: "Scoped user mode access and related changes: - Implement the missing u64 user access function on ARM when CONFIG_CPU_SPECTRE=n. This makes it possible to access a 64bit value in generic code with [unsafe_]get_user(). All other architectures and ARM variants provide the relevant accessors already. - Ensure that ASM GOTO jump label usage in the user mode access helpers always goes through a local C scope label indirection inside the helpers. This is required because compilers are not supporting that a ASM GOTO target leaves a auto cleanup scope. GCC silently fails to emit the cleanup invocation and CLANG fails the build. [ Editor's note: gcc-16 will have fixed the code generation issue in commit f68fe3ddda4 ("eh: Invoke cleanups/destructors in asm goto jumps [PR122835]"). But we obviously have to deal with clang and older versions of gcc, so.. - Linus ] This provides generic wrapper macros and the conversion of affected architecture code to use them. - Scoped user mode access with auto cleanup Access to user mode memory can be required in hot code paths, but if it has to be done with user controlled pointers, the access is shielded with a speculation barrier, so that the CPU cannot speculate around the address range check. Those speculation barriers impact performance quite significantly. This cost can be avoided by "masking" the provided pointer so it is guaranteed to be in the valid user memory access range and otherwise to point to a guaranteed unpopulated address space. This has to be done without branches so it creates an address dependency for the access, which the CPU cannot speculate ahead. This results in repeating and error prone programming patterns: if (can_do_masked_user_access()) from = masked_user_read_access_begin((from)); else if (!user_read_access_begin(from, sizeof(*from))) return -EFAULT; unsafe_get_user(val, from, Efault); user_read_access_end(); return 0; Efault: user_read_access_end(); return -EFAULT; which can be replaced with scopes and automatic cleanup: scoped_user_read_access(from, Efault) unsafe_get_user(val, from, Efault); return 0; Efault: return -EFAULT; - Convert code which implements the above pattern over to scope_user.*.access(). This also corrects a couple of imbalanced masked_*_begin() instances which are harmless on most architectures, but prevent PowerPC from implementing the masking optimization. - Add a missing speculation barrier in copy_from_user_iter()" * tag 'core-uaccess-2025-11-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: lib/strn*,uaccess: Use masked_user_{read/write}_access_begin when required scm: Convert put_cmsg() to scoped user access iov_iter: Add missing speculation barrier to copy_from_user_iter() iov_iter: Convert copy_from_user_iter() to masked user access select: Convert to scoped user access x86/futex: Convert to scoped user access futex: Convert to get/put_user_inline() uaccess: Provide put/get_user_inline() uaccess: Provide scoped user access regions arm64: uaccess: Use unsafe wrappers for ASM GOTO s390/uaccess: Use unsafe wrappers for ASM GOTO riscv/uaccess: Use unsafe wrappers for ASM GOTO powerpc/uaccess: Use unsafe wrappers for ASM GOTO x86/uaccess: Use unsafe wrappers for ASM GOTO uaccess: Provide ASM GOTO safe wrappers for unsafe_*_user() ARM: uaccess: Implement missing __get_user_asm_dword()
2025-12-01Merge tag 'core-bugs-2025-12-01' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull bug handling infrastructure updates from Ingo Molnar: "Core updates: - Improve WARN(), which has vararg printf like arguments, to work with the x86 #UD based WARN-optimizing infrastructure by hiding the format in the bug_table and replacing this first argument with the address of the bug-table entry, while making the actual function that's called a UD1 instruction (Peter Zijlstra) - Introduce the CONFIG_DEBUG_BUGVERBOSE_DETAILED Kconfig switch (Ingo Molnar, s390 support by Heiko Carstens) Fixes and cleanups: - bugs/s390: Remove private WARN_ON() implementation (Heiko Carstens) - <asm/bugs.h>: Make i386 use GENERIC_BUG_RELATIVE_POINTERS (Peter Zijlstra)" * tag 'core-bugs-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits) x86/bugs: Make i386 use GENERIC_BUG_RELATIVE_POINTERS x86/bug: Fix BUG_FORMAT vs KASLR x86_64/bug: Inline the UD1 x86/bug: Implement WARN_ONCE() x86_64/bug: Implement __WARN_printf() x86/bug: Use BUG_FORMAT for DEBUG_BUGVERBOSE_DETAILED x86/bug: Add BUG_FORMAT basics bug: Allow architectures to provide __WARN_printf() bug: Implement WARN_ON() using __WARN_FLAGS() bug: Add report_bug_entry() bug: Add BUG_FORMAT_ARGS infrastructure bug: Clean up CONFIG_GENERIC_BUG_RELATIVE_POINTERS bug: Add BUG_FORMAT infrastructure x86: Rework __bug_table helpers bugs/s390: Remove private WARN_ON() implementation bugs/core: Reorganize fields in the first line of WARNING output, add ->comm[] output bugs/sh: Concatenate 'cond_str' with '__FILE__' in __WARN_FLAGS(), to extend WARN_ON/BUG_ON output bugs/parisc: Concatenate 'cond_str' with '__FILE__' in __WARN_FLAGS(), to extend WARN_ON/BUG_ON output bugs/riscv: Concatenate 'cond_str' with '__FILE__' in __BUG_FLAGS(), to extend WARN_ON/BUG_ON output bugs/riscv: Pass in 'cond_str' to __BUG_FLAGS() ...