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* Merge tag 'x86-mm-2024-11-18' of ↵Linus Torvalds2024-11-191-6/+29
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm updates from Ingo Molnar: - Put cpumask_test_cpu() check in switch_mm_irqs_off() under CONFIG_DEBUG_VM, to micro-optimize the context-switching code (Rik van Riel) - Add missing details in virtual memory layout (Kirill A. Shutemov) * tag 'x86-mm-2024-11-18' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm/tlb: Put cpumask_test_cpu() check in switch_mm_irqs_off() under CONFIG_DEBUG_VM x86/mm/doc: Add missing details in virtual memory layout
| * x86/mm/doc: Add missing details in virtual memory layoutKirill A. Shutemov2024-11-011-6/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Improve memory layout documentation: - Document 4kB guard hole at the end of userspace. See TASK_SIZE_MAX definition. - Divide the description of the non-canonical hole into two parts: userspace and kernel sides. - Mention the effect of LAM on the non-canonical range. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/all/20241031084946.2243440-1-kirill.shutemov%40linux.intel.com
* | Merge tag 'x86-splitlock-2024-11-18' of ↵Linus Torvalds2024-11-191-1/+2
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 splitlock updates from Ingo Molnar: - Move Split and Bus lock code to a dedicated file (Ravi Bangoria) - Add split/bus lock support for AMD (Ravi Bangoria) * tag 'x86-splitlock-2024-11-18' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/bus_lock: Add support for AMD x86/split_lock: Move Split and Bus lock code to a dedicated file
| * | x86/bus_lock: Add support for AMDRavi Bangoria2024-08-081-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add Bus Lock Detect (called Bus Lock Trap in AMD docs) support for AMD platforms. Bus Lock Detect is enumerated with CPUID Fn0000_0007_ECX_x0 bit [24 / BUSLOCKTRAP]. It can be enabled through MSR_IA32_DEBUGCTLMSR. When enabled, hardware clears DR6[11] and raises a #DB exception on occurrence of Bus Lock if CPL > 0. More detail about the feature can be found in AMD APM[1]. [1]: AMD64 Architecture Programmer's Manual Pub. 40332, Rev. 4.07 - June 2023, Vol 2, 13.1.3.6 Bus Lock Trap https://bugzilla.kernel.org/attachment.cgi?id=304653 Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/all/20240808062937.1149-3-ravi.bangoria@amd.com
* | | Merge tag 'x86_sev_for_v6.13' of ↵Linus Torvalds2024-11-191-0/+5
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 SEV updates from Borislav Petkov: - Do the proper memory conversion of guest memory in order to be able to kexec kernels in SNP guests along with other adjustments and cleanups to that effect - Start converting and moving functionality from the sev-guest driver into core code with the purpose of supporting the secure TSC SNP feature where the hypervisor cannot influence the TSC exposed to the guest anymore - Add a "nosnp" cmdline option in order to be able to disable SNP support in the hypervisor and thus free-up resources which are not going to be used - Cleanups [ Reminding myself about the endless TLA's again: SEV is the AMD Secure Encrypted Virtualization - Linus ] * tag 'x86_sev_for_v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/sev: Cleanup vc_handle_msr() x86/sev: Convert shared memory back to private on kexec x86/mm: Refactor __set_clr_pte_enc() x86/boot: Skip video memory access in the decompressor for SEV-ES/SNP virt: sev-guest: Carve out SNP message context structure virt: sev-guest: Reduce the scope of SNP command mutex virt: sev-guest: Consolidate SNP guest messaging parameters to a struct x86/sev: Cache the secrets page address x86/sev: Handle failures from snp_init() virt: sev-guest: Use AES GCM crypto library x86/virt: Provide "nosnp" boot option for sev kernel command line x86/virt: Move SEV-specific parsing into arch/x86/virt/svm
| * | | x86/virt: Provide "nosnp" boot option for sev kernel command linePavan Kumar Paluri2024-10-151-0/+5
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Provide a "nosnp" kernel command line option to prevent enabling of the RMP and SEV-SNP features in the host/hypervisor. Not initializing the RMP removes system overhead associated with RMP checks. [ bp: Actually make it a HV-only cmdline option. ] Co-developed-by: Eric Van Tassell <Eric.VanTassell@amd.com> Signed-off-by: Eric Van Tassell <Eric.VanTassell@amd.com> Signed-off-by: Pavan Kumar Paluri <papaluri@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20241014130948.1476946-3-papaluri@amd.com
* | | Merge branch 'for-next/mops' into for-next/coreCatalin Marinas2024-11-143-0/+48
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 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
| * | | arm64: mops: Document requirements for hypervisorsKristina Martsenko2024-11-013-2/+47
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | arm64: mops: Document booting requirement for HCR_EL2.MCE2Kristina Martsenko2024-10-171-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
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*---------. \ \ \ Merge branches 'for-next/gcs', 'for-next/probes', 'for-next/asm-offsets', ↵Catalin Marinas2024-11-147-3/+348
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| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | '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
| | | | | | * | arm64: Document Arm Confidential ComputeSteven Price2024-10-233-0/+73
| | | | |_|/ / | | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| | | | | * | arm64: Support AT_HWCAP3Mark Brown2024-10-171-3/+3
| | | | |/ / | | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| | | | * | arm64/ptrace: Clarify documentation of VL configuration via ptraceMark Brown2024-11-122-0/+8
| | | |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | | arm64/gcs: Fix outdated ptrace documentationMark Brown2024-11-011-5/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | | arm64/hwcap: Add hwcap for GCSMark Brown2024-10-041-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | | arm64/gcs: Document the ABI for Guarded Control StacksMark Brown2024-10-042-0/+231
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | | arm64: Document boot requirements for Guarded Control StacksMark Brown2024-10-041-0/+32
| | |/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | | Merge tag 'arm64-fixes' of ↵Linus Torvalds2024-10-041-0/+6
|\ \ \ \ | | |/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Catalin Marinas: "A couple of build/config issues and expanding the speculative SSBS workaround to more CPUs: - Expand the speculative SSBS workaround to cover Cortex-A715, Neoverse-N3 and Microsoft Azure Cobalt 100 - Force position-independent veneers - in some kernel configurations, the LLD linker generates position-dependent veneers for otherwise position-independent code, resulting in early boot-time failures - Fix Kconfig selection of HAVE_DYNAMIC_FTRACE_WITH_ARGS so that it is not enabled when not supported by the combination of clang and GNU ld" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: Subscribe Microsoft Azure Cobalt 100 to erratum 3194386 arm64: fix selection of HAVE_DYNAMIC_FTRACE_WITH_ARGS arm64: errata: Expand speculative SSBS workaround once more arm64: cputype: Add Neoverse-N3 definitions arm64: Force position-independent veneers
| * | | arm64: Subscribe Microsoft Azure Cobalt 100 to erratum 3194386Easwar Hariharan2024-10-041-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | arm64: errata: Expand speculative SSBS workaround once moreMark Rutland2024-10-011-0/+4
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* / / move asm/unaligned.h to linux/unaligned.hAl Viro2024-10-021-1/+1
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | asm/unaligned.h is always an include of asm-generic/unaligned.h; might as well move that thing to linux/unaligned.h and include that - there's nothing arch-specific in that header. auto-generated by the following: for i in `git grep -l -w asm/unaligned.h`; do sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i done for i in `git grep -l -w asm-generic/unaligned.h`; do sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i done git mv include/asm-generic/unaligned.h include/linux/unaligned.h git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
* | Merge tag 's390-6.12-2' of ↵Linus Torvalds2024-09-281-0/+30
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull more s390 updates from Vasily Gorbik: - Clean up and improve vdso code: use SYM_* macros for function and data annotations, add CFI annotations to fix GDB unwinding, optimize the chacha20 implementation - Add vfio-ap driver feature advertisement for use by libvirt and mdevctl * tag 's390-6.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/vfio-ap: Driver feature advertisement s390/vdso: Use one large alternative instead of an alternative branch s390/vdso: Use SYM_DATA_START_LOCAL()/SYM_DATA_END() for data objects tools: Add additional SYM_*() stubs to linkage.h s390/vdso: Use macros for annotation of asm functions s390/vdso: Add CFI annotations to __arch_chacha20_blocks_nostack() s390/vdso: Fix comment within __arch_chacha20_blocks_nostack() s390/vdso: Get rid of permutation constants
| * | s390/vfio-ap: Driver feature advertisementJason J. Herne2024-09-231-0/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Advertise features of the driver for the benefit of automated tooling like Libvirt and mdevctl. Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com> Reviewed-by: Anthony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Boris Fiuczynski <fiuczy@linux.ibm.com> Link: https://lore.kernel.org/r/20240916120123.11484-1-jjherne@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
* | | Merge tag 'loongarch-6.12' of ↵Linus Torvalds2024-09-271-0/+32
|\ \ \ | |/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson Pull LoongArch updates from Huacai Chen: - Fix objtool about do_syscall() and Clang - Enable generic CPU vulnerabilites support - Enable ACPI BGRT handling - Rework CPU feature probe from CPUCFG/IOCSR - Add ARCH_HAS_SET_MEMORY support - Add ARCH_HAS_SET_DIRECT_MAP support - Improve hardware page table walker - Simplify _percpu_read() and _percpu_write() - Add advanced extended IRQ model documentions - Some bug fixes and other small changes * tag 'loongarch-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: Docs/LoongArch: Add advanced extended IRQ model description LoongArch: Remove posix_types.h include from sigcontext.h LoongArch: Fix memleak in pci_acpi_scan_root() LoongArch: Simplify _percpu_read() and _percpu_write() LoongArch: Improve hardware page table walker LoongArch: Add ARCH_HAS_SET_DIRECT_MAP support LoongArch: Add ARCH_HAS_SET_MEMORY support LoongArch: Rework CPU feature probe from CPUCFG/IOCSR LoongArch: Enable ACPI BGRT handling LoongArch: Enable generic CPU vulnerabilites support LoongArch: Remove STACK_FRAME_NON_STANDARD(do_syscall) LoongArch: Set AS_HAS_THIN_ADD_SUB as y if AS_IS_LLVM LoongArch: Enable objtool for Clang objtool: Handle frame pointer related instructions
| * | Docs/LoongArch: Add advanced extended IRQ model descriptionHuacai Chen2024-09-241-0/+32
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce the advanced extended interrupt controllers (AVECINTC). This feature will allow each core to have 256 independent interrupt vectors and MSI interrupts can be independently routed to any vector on any CPU. The whole topology of irqchips in LoongArch machines looks like this if AVECINTC is supported: +-----+ +-----------------------+ +-------+ | IPI | --> | CPUINTC | <-- | Timer | +-----+ +-----------------------+ +-------+ ^ ^ ^ | | | +---------+ +----------+ +---------+ +-------+ | EIOINTC | | AVECINTC | | LIOINTC | <-- | UARTs | +---------+ +----------+ +---------+ +-------+ ^ ^ | | +---------+ +---------+ | PCH-PIC | | PCH-MSI | +---------+ +---------+ ^ ^ ^ | | | +---------+ +---------+ +---------+ | Devices | | PCH-LPC | | Devices | +---------+ +---------+ +---------+ ^ | +---------+ | Devices | +---------+ Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> Signed-off-by: Tianyang Zhang <zhangtianyang@loongson.cn>
* | | Merge tag 'mm-stable-2024-09-20-02-31' of ↵Linus Torvalds2024-09-211-12/+0
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "Along with the usual shower of singleton patches, notable patch series in this pull request are: - "Align kvrealloc() with krealloc()" from Danilo Krummrich. Adds consistency to the APIs and behaviour of these two core allocation functions. This also simplifies/enables Rustification. - "Some cleanups for shmem" from Baolin Wang. No functional changes - mode code reuse, better function naming, logic simplifications. - "mm: some small page fault cleanups" from Josef Bacik. No functional changes - code cleanups only. - "Various memory tiering fixes" from Zi Yan. A small fix and a little cleanup. - "mm/swap: remove boilerplate" from Yu Zhao. Code cleanups and simplifications and .text shrinkage. - "Kernel stack usage histogram" from Pasha Tatashin and Shakeel Butt. This is a feature, it adds new feilds to /proc/vmstat such as $ grep kstack /proc/vmstat kstack_1k 3 kstack_2k 188 kstack_4k 11391 kstack_8k 243 kstack_16k 0 which tells us that 11391 processes used 4k of stack while none at all used 16k. Useful for some system tuning things, but partivularly useful for "the dynamic kernel stack project". - "kmemleak: support for percpu memory leak detect" from Pavel Tikhomirov. Teaches kmemleak to detect leaksage of percpu memory. - "mm: memcg: page counters optimizations" from Roman Gushchin. "3 independent small optimizations of page counters". - "mm: split PTE/PMD PT table Kconfig cleanups+clarifications" from David Hildenbrand. Improves PTE/PMD splitlock detection, makes powerpc/8xx work correctly by design rather than by accident. - "mm: remove arch_make_page_accessible()" from David Hildenbrand. Some folio conversions which make arch_make_page_accessible() unneeded. - "mm, memcg: cg2 memory{.swap,}.peak write handlers" fro David Finkel. Cleans up and fixes our handling of the resetting of the cgroup/process peak-memory-use detector. - "Make core VMA operations internal and testable" from Lorenzo Stoakes. Rationalizaion and encapsulation of the VMA manipulation APIs. With a view to better enable testing of the VMA functions, even from a userspace-only harness. - "mm: zswap: fixes for global shrinker" from Takero Funaki. Fix issues in the zswap global shrinker, resulting in improved performance. - "mm: print the promo watermark in zoneinfo" from Kaiyang Zhao. Fill in some missing info in /proc/zoneinfo. - "mm: replace follow_page() by folio_walk" from David Hildenbrand. Code cleanups and rationalizations (conversion to folio_walk()) resulting in the removal of follow_page(). - "improving dynamic zswap shrinker protection scheme" from Nhat Pham. Some tuning to improve zswap's dynamic shrinker. Significant reductions in swapin and improvements in performance are shown. - "mm: Fix several issues with unaccepted memory" from Kirill Shutemov. Improvements to the new unaccepted memory feature, - "mm/mprotect: Fix dax puds" from Peter Xu. Implements mprotect on DAX PUDs. This was missing, although nobody seems to have notied yet. - "Introduce a store type enum for the Maple tree" from Sidhartha Kumar. Cleanups and modest performance improvements for the maple tree library code. - "memcg: further decouple v1 code from v2" from Shakeel Butt. Move more cgroup v1 remnants away from the v2 memcg code. - "memcg: initiate deprecation of v1 features" from Shakeel Butt. Adds various warnings telling users that memcg v1 features are deprecated. - "mm: swap: mTHP swap allocator base on swap cluster order" from Chris Li. Greatly improves the success rate of the mTHP swap allocation. - "mm: introduce numa_memblks" from Mike Rapoport. Moves various disparate per-arch implementations of numa_memblk code into generic code. - "mm: batch free swaps for zap_pte_range()" from Barry Song. Greatly improves the performance of munmap() of swap-filled ptes. - "support large folio swap-out and swap-in for shmem" from Baolin Wang. With this series we no longer split shmem large folios into simgle-page folios when swapping out shmem. - "mm/hugetlb: alloc/free gigantic folios" from Yu Zhao. Nice performance improvements and code reductions for gigantic folios. - "support shmem mTHP collapse" from Baolin Wang. Adds support for khugepaged's collapsing of shmem mTHP folios. - "mm: Optimize mseal checks" from Pedro Falcato. Fixes an mprotect() performance regression due to the addition of mseal(). - "Increase the number of bits available in page_type" from Matthew Wilcox. Increases the number of bits available in page_type! - "Simplify the page flags a little" from Matthew Wilcox. Many legacy page flags are now folio flags, so the page-based flags and their accessors/mutators can be removed. - "mm: store zero pages to be swapped out in a bitmap" from Usama Arif. An optimization which permits us to avoid writing/reading zero-filled zswap pages to backing store. - "Avoid MAP_FIXED gap exposure" from Liam Howlett. Fixes a race window which occurs when a MAP_FIXED operqtion is occurring during an unrelated vma tree walk. - "mm: remove vma_merge()" from Lorenzo Stoakes. Major rotorooting of the vma_merge() functionality, making ot cleaner, more testable and better tested. - "misc fixups for DAMON {self,kunit} tests" from SeongJae Park. Minor fixups of DAMON selftests and kunit tests. - "mm: memory_hotplug: improve do_migrate_range()" from Kefeng Wang. Code cleanups and folio conversions. - "Shmem mTHP controls and stats improvements" from Ryan Roberts. Cleanups for shmem controls and stats. - "mm: count the number of anonymous THPs per size" from Barry Song. Expose additional anon THP stats to userspace for improved tuning. - "mm: finish isolate/putback_lru_page()" from Kefeng Wang: more folio conversions and removal of now-unused page-based APIs. - "replace per-quota region priorities histogram buffer with per-context one" from SeongJae Park. DAMON histogram rationalization. - "Docs/damon: update GitHub repo URLs and maintainer-profile" from SeongJae Park. DAMON documentation updates. - "mm/vdpa: correct misuse of non-direct-reclaim __GFP_NOFAIL and improve related doc and warn" from Jason Wang: fixes usage of page allocator __GFP_NOFAIL and GFP_ATOMIC flags. - "mm: split underused THPs" from Yu Zhao. Improve THP=always policy. This was overprovisioning THPs in sparsely accessed memory areas. - "zram: introduce custom comp backends API" frm Sergey Senozhatsky. Add support for zram run-time compression algorithm tuning. - "mm: Care about shadow stack guard gap when getting an unmapped area" from Mark Brown. Fix up the various arch_get_unmapped_area() implementations to better respect guard areas. - "Improve mem_cgroup_iter()" from Kinsey Ho. Improve the reliability of mem_cgroup_iter() and various code cleanups. - "mm: Support huge pfnmaps" from Peter Xu. Extends the usage of huge pfnmap support. - "resource: Fix region_intersects() vs add_memory_driver_managed()" from Huang Ying. Fix a bug in region_intersects() for systems with CXL memory. - "mm: hwpoison: two more poison recovery" from Kefeng Wang. Teaches a couple more code paths to correctly recover from the encountering of poisoned memry. - "mm: enable large folios swap-in support" from Barry Song. Support the swapin of mTHP memory into appropriately-sized folios, rather than into single-page folios" * tag 'mm-stable-2024-09-20-02-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (416 commits) zram: free secondary algorithms names uprobes: turn xol_area->pages[2] into xol_area->page uprobes: introduce the global struct vm_special_mapping xol_mapping Revert "uprobes: use vm_special_mapping close() functionality" mm: support large folios swap-in for sync io devices mm: add nr argument in mem_cgroup_swapin_uncharge_swap() helper to support large folios mm: fix swap_read_folio_zeromap() for large folios with partial zeromap mm/debug_vm_pgtable: Use pxdp_get() for accessing page table entries set_memory: add __must_check to generic stubs mm/vma: return the exact errno in vms_gather_munmap_vmas() memcg: cleanup with !CONFIG_MEMCG_V1 mm/show_mem.c: report alloc tags in human readable units mm: support poison recovery from copy_present_page() mm: support poison recovery from do_cow_fault() resource, kunit: add test case for region_intersects() resource: make alloc_free_mem_region() works for iomem_resource mm: z3fold: deprecate CONFIG_Z3FOLD vfio/pci: implement huge_fault support mm/arm64: support large pfn mappings mm/x86: support large pfn mappings ...
| * | | docs: move numa=fake description to kernel-parameters.txtMike Rapoport (Microsoft)2024-09-041-12/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | NUMA emulation can be now enabled on arm64 and riscv in addition to x86. Move description of numa=fake parameters from x86 documentation of admin-guide/kernel-parameters.txt Link: https://lkml.kernel.org/r/20240807064110.1003856-27-rppt@kernel.org Suggested-by: Zi Yan <ziy@nvidia.com> Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> [arm64 + CXL via QEMU] Acked-by: Dan Williams <dan.j.williams@intel.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: David S. Miller <davem@davemloft.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Rafael J. Wysocki <rafael@kernel.org> Cc: Rob Herring (Arm) <robh@kernel.org> Cc: Samuel Holland <samuel.holland@sifive.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | | | Merge tag 'docs-6.12' of git://git.lwn.net/linuxLinus Torvalds2024-09-176-8/+8
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * | | | Documentation: Fix spelling mistakesAmit Vadhavana2024-09-056-8/+8
| |/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* | | | Merge tag 'arm64-upstream' of ↵Linus Torvalds2024-09-162-2/+6
|\ \ \ \ | |_|/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "The highlights are support for Arm's "Permission Overlay Extension" using memory protection keys, support for running as a protected guest on Android as well as perf support for a bunch of new interconnect PMUs. Summary: ACPI: - Enable PMCG erratum workaround for HiSilicon HIP10 and 11 platforms. - Ensure arm64-specific IORT header is covered by MAINTAINERS. CPU Errata: - Enable workaround for hardware access/dirty issue on Ampere-1A cores. Memory management: - Define PHYSMEM_END to fix a crash in the amdgpu driver. - Avoid tripping over invalid kernel mappings on the kexec() path. - Userspace support for the Permission Overlay Extension (POE) using protection keys. Perf and PMUs: - Add support for the "fixed instruction counter" extension in the CPU PMU architecture. - Extend and fix the event encodings for Apple's M1 CPU PMU. - Allow LSM hooks to decide on SPE permissions for physical profiling. - Add support for the CMN S3 and NI-700 PMUs. Confidential Computing: - Add support for booting an arm64 kernel as a protected guest under Android's "Protected KVM" (pKVM) hypervisor. Selftests: - Fix vector length issues in the SVE/SME sigreturn tests - Fix build warning in the ptrace tests. Timers: - Add support for PR_{G,S}ET_TSC so that 'rr' can deal with non-determinism arising from the architected counter. Miscellaneous: - Rework our IPI-based CPU stopping code to try NMIs if regular IPIs don't succeed. - Minor fixes and cleanups" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (94 commits) perf: arm-ni: Fix an NULL vs IS_ERR() bug arm64: hibernate: Fix warning for cast from restricted gfp_t arm64: esr: Define ESR_ELx_EC_* constants as UL arm64: pkeys: remove redundant WARN perf: arm_pmuv3: Use BR_RETIRED for HW branch event if enabled MAINTAINERS: List Arm interconnect PMUs as supported perf: Add driver for Arm NI-700 interconnect PMU dt-bindings/perf: Add Arm NI-700 PMU perf/arm-cmn: Improve format attr printing perf/arm-cmn: Clean up unnecessary NUMA_NO_NODE check arm64/mm: use lm_alias() with addresses passed to memblock_free() mm: arm64: document why pte is not advanced in contpte_ptep_set_access_flags() arm64: Expose the end of the linear map in PHYSMEM_END arm64: trans_pgd: mark PTEs entries as valid to avoid dead kexec() arm64/mm: Delete __init region from memblock.reserved perf/arm-cmn: Support CMN S3 dt-bindings: perf: arm-cmn: Add CMN S3 perf/arm-cmn: Refactor DTC PMU register access perf/arm-cmn: Make cycle counts less surprising perf/arm-cmn: Improve build-time assertion ...
| * | | Merge branch 'for-next/poe' into for-next/coreWill Deacon2024-09-121-0/+2
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 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 ...
| | * | | arm64: enable the Permission Overlay Extension for EL0Joey Gouly2024-09-041-0/+2
| | | |/ | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | Merge branch 'for-next/errata' into for-next/coreWill Deacon2024-09-121-0/+2
| |\ \ \ | | | | | | | | | | | | | | | | | | | | * for-next/errata: arm64: errata: Enable the AC03_CPU_38 workaround for ampere1a
| | * | | arm64: errata: Enable the AC03_CPU_38 workaround for ampere1aD Scott Phillips2024-08-301-0/+2
| | |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The ampere1a cpu is affected by erratum AC04_CPU_10 which is the same bug as AC03_CPU_38. Add ampere1a to the AC03_CPU_38 workaround midr list. Cc: <stable@vger.kernel.org> Signed-off-by: D Scott Phillips <scott@os.amperecomputing.com> Acked-by: Oliver Upton <oliver.upton@linux.dev> Link: https://lore.kernel.org/r/20240827211701.2216719-1-scott@os.amperecomputing.com Signed-off-by: Will Deacon <will@kernel.org>
| * / / ACPI/IORT: Add PMCG platform information for HiSilicon HIP10/11Yicong Yang2024-08-201-2/+2
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | HiSilicon HIP10/11 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. Signed-off-by: Yicong Yang <yangyicong@hisilicon.com> Link: https://lore.kernel.org/r/20240731092658.11012-1-yangyicong@huawei.com Signed-off-by: Will Deacon <will@kernel.org>
* | | Merge patch series "riscv: mm: Do not restrict mmap address based on hint"Palmer Dabbelt2024-08-291-16/+0
|\ \ \ | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Charlie Jenkins <charlie@rivosinc.com> says: There have been a couple of reports that using the hint address to restrict the address returned by mmap hint address has caused issues in applications. A different solution for restricting addresses returned by mmap is necessary to avoid breakages. [Palmer: This also just wasn't doing the right thing in the first place, as it didn't handle the sv39 cases we were trying to deal with.] * b4-shazam-merge: riscv: mm: Do not restrict mmap address based on hint riscv: selftests: Remove mmap hint address checks Revert "RISC-V: mm: Document mmap changes" Link: https://lore.kernel.org/r/20240826-riscv_mmap-v1-0-cd8962afe47f@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| * | Revert "RISC-V: mm: Document mmap changes"Charlie Jenkins2024-08-291-16/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | This mmap behavior caused unintended breakages so the behavior has been changed. Signed-off-by: Charlie Jenkins <charlie@rivosinc.com> Link: https://lore.kernel.org/r/20240826-riscv_mmap-v1-1-cd8962afe47f@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
* | | Merge patch series "RISC-V: hwprobe: Misaligned scalar perf fix and rename"Palmer Dabbelt2024-08-151-14/+22
|\ \ \ | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Evan Green <evan@rivosinc.com> says: The CPUPERF0 hwprobe key was documented and identified in code as a bitmask value, but its contents were an enum. This produced incorrect behavior in conjunction with the WHICH_CPUS hwprobe flag. The first patch in this series fixes the bitmask/enum problem by creating a new hwprobe key that returns the same data, but is properly described as a value instead of a bitmask. The second patch renames the value definitions in preparation for adding vector misaligned access info. As of this version, the old defines are kept in place to maintain source compatibility with older userspace programs. * b4-shazam-merge: RISC-V: hwprobe: Add SCALAR to misaligned perf defines RISC-V: hwprobe: Add MISALIGNED_PERF key Link: https://lore.kernel.org/r/20240809214444.3257596-1-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| * | RISC-V: hwprobe: Add SCALAR to misaligned perf definesEvan Green2024-08-141-13/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In preparation for misaligned vector performance hwprobe keys, rename the hwprobe key values associated with misaligned scalar accesses to include the term SCALAR. Leave the old defines in place to maintain source compatibility. This change is intended to be a functional no-op. Signed-off-by: Evan Green <evan@rivosinc.com> Reviewed-by: Charlie Jenkins <charlie@rivosinc.com> Link: https://lore.kernel.org/r/20240809214444.3257596-3-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| * | RISC-V: hwprobe: Add MISALIGNED_PERF keyEvan Green2024-08-141-7/+13
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | RISCV_HWPROBE_KEY_CPUPERF_0 was mistakenly flagged as a bitmask in hwprobe_key_is_bitmask(), when in reality it was an enum value. This causes problems when used in conjunction with RISCV_HWPROBE_WHICH_CPUS, since SLOW, FAST, and EMULATED have values whose bits overlap with each other. If the caller asked for the set of CPUs that was SLOW or EMULATED, the returned set would also include CPUs that were FAST. Introduce a new hwprobe key, RISCV_HWPROBE_KEY_MISALIGNED_PERF, which returns the same values in response to a direct query (with no flags), but is properly handled as an enumerated value. As a result, SLOW, FAST, and EMULATED are all correctly treated as distinct values under the new key when queried with the WHICH_CPUS flag. Leave the old key in place to avoid disturbing applications which may have already come to rely on the key, with or without its broken behavior with respect to the WHICH_CPUS flag. Fixes: e178bf146e4b ("RISC-V: hwprobe: Introduce which-cpus flag") Signed-off-by: Evan Green <evan@rivosinc.com> Reviewed-by: Charlie Jenkins <charlie@rivosinc.com> Reviewed-by: Andrew Jones <ajones@ventanamicro.com> Link: https://lore.kernel.org/r/20240809214444.3257596-2-evan@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
* / arm64: errata: Expand speculative SSBS workaround (again)Mark Rutland2024-08-011-0/+18
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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") Since then, similar errata have been published for a number of other Arm Ltd CPUs, for which the same mitigation is sufficient. This is described in their respective Software Developer Errata Notice (SDEN) documents: * Cortex-A76 (MP052) SDEN v31.0, erratum 3324349 https://developer.arm.com/documentation/SDEN-885749/3100/ * Cortex-A77 (MP074) SDEN v19.0, erratum 3324348 https://developer.arm.com/documentation/SDEN-1152370/1900/ * Cortex-A78 (MP102) SDEN v21.0, erratum 3324344 https://developer.arm.com/documentation/SDEN-1401784/2100/ * Cortex-A78C (MP138) SDEN v16.0, erratum 3324346 https://developer.arm.com/documentation/SDEN-1707916/1600/ * Cortex-A78C (MP154) SDEN v10.0, erratum 3324347 https://developer.arm.com/documentation/SDEN-2004089/1000/ * Cortex-A725 (MP190) SDEN v5.0, erratum 3456106 https://developer.arm.com/documentation/SDEN-2832921/0500/ * Cortex-X1 (MP077) SDEN v21.0, erratum 3324344 https://developer.arm.com/documentation/SDEN-1401782/2100/ * Cortex-X1C (MP136) SDEN v16.0, erratum 3324346 https://developer.arm.com/documentation/SDEN-1707914/1600/ * Neoverse-N1 (MP050) SDEN v32.0, erratum 3324349 https://developer.arm.com/documentation/SDEN-885747/3200/ * Neoverse-V1 (MP076) SDEN v19.0, erratum 3324341 https://developer.arm.com/documentation/SDEN-1401781/1900/ Note that due to the manner in which Arm develops IP and tracks errata, some CPUs share a common erratum number and some CPUs have multiple erratum numbers for the same HW issue. On parts without SB, it is necessary to use ISB for the workaround. The spec_bar() macro used in the mitigation will expand to a "DSB SY; ISB" sequence in this case, which is sufficient on all affected parts. Enable the existing mitigation by adding the relevant MIDRs to erratum_spec_ssbs_list. The list is sorted alphanumerically (involving moving Neoverse-V3 after Neoverse-V2) so that this is easy to audit and potentially extend again in future. The Kconfig text is also updated to clarify the set of affected parts and the mitigation. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Will Deacon <will@kernel.org> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Acked-by: Will Deacon <will@kernel.org> Link: https://lore.kernel.org/r/20240801101803.1982459-4-mark.rutland@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* RISC-V: Provide the frequency of time CSR via hwprobePalmer Dabbelt2024-07-261-0/+2
| | | | | | | | | | | | | | | | | | | The RISC-V architecture makes a real time counter CSR (via RDTIME instruction) available for applications in U-mode but there is no architected mechanism for an application to discover the frequency the counter is running at. Some applications (e.g., DPDK) use the time counter for basic performance analysis as well as fine grained time-keeping. Add support to the hwprobe system call to export the time CSR frequency to code running in U-mode. Signed-off-by: Yunhui Cui <cuiyunhui@bytedance.com> Reviewed-by: Evan Green <evan@rivosinc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Acked-by: Punit Agrawal <punit.agrawal@bytedance.com> Link: https://lore.kernel.org/r/20240702033731.71955-2-cuiyunhui@bytedance.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
* riscv: Extend sv39 linear mapping max size to 128GStuart Menefy2024-07-261-5/+6
| | | | | | | | | | | | | | | | | | This harmonizes all virtual addressing modes which can now all map (PGDIR_SIZE * PTRS_PER_PGD) / 4 of physical memory. The RISCV implementation of KASAN requires that the boundary between shallow mappings are aligned on an 8G boundary. In this case we need VMALLOC_START to be 8G aligned. So although we only need to move the start of the linear mapping down by 4GiB to allow 128GiB to be mapped, we actually move it down by 8GiB (creating a 4GiB hole between the linear mapping and KASAN shadow space) to maintain the alignment requirement. Signed-off-by: Stuart Menefy <stuart.menefy@codasip.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20240630110550.1731929-1-stuart.menefy@codasip.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
* Merge tag 'riscv-for-linus-6.11-mw1' of ↵Linus Torvalds2024-07-201-0/+50
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V updates from Palmer Dabbelt: - Support for various new ISA extensions: * The Zve32[xf] and Zve64[xfd] sub-extensios of the vector extension * Zimop and Zcmop for may-be-operations * The Zca, Zcf, Zcd and Zcb sub-extensions of the C extension * Zawrs - riscv,cpu-intc is now dtschema - A handful of performance improvements and cleanups to text patching - Support for memory hot{,un}plug - The highest user-allocatable virtual address is now visible in hwprobe * tag 'riscv-for-linus-6.11-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (58 commits) riscv: lib: relax assembly constraints in hweight riscv: set trap vector earlier KVM: riscv: selftests: Add Zawrs extension to get-reg-list test KVM: riscv: Support guest wrs.nto riscv: hwprobe: export Zawrs ISA extension riscv: Add Zawrs support for spinlocks dt-bindings: riscv: Add Zawrs ISA extension description riscv: Provide a definition for 'pause' riscv: hwprobe: export highest virtual userspace address riscv: Improve sbi_ecall() code generation by reordering arguments riscv: Add tracepoints for SBI calls and returns riscv: Optimize crc32 with Zbc extension riscv: Enable DAX VMEMMAP optimization riscv: mm: Add support for ZONE_DEVICE virtio-mem: Enable virtio-mem for RISC-V riscv: Enable memory hotplugging for RISC-V riscv: mm: Take memory hotplug read-lock during kernel page table dump riscv: mm: Add memory hotplugging support riscv: mm: Add pfn_to_kaddr() implementation riscv: mm: Refactor create_linear_mapping_range() for memory hot add ...
| * Merge patch series "riscv: Apply Zawrs when available"Palmer Dabbelt2024-07-121-0/+4
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Andrew Jones <ajones@ventanamicro.com> says: Zawrs provides two instructions (wrs.nto and wrs.sto), where both are meant to allow the hart to enter a low-power state while waiting on a store to a memory location. The instructions also both wait an implementation-defined "short" duration (unless the implementation terminates the stall for another reason). The difference is that while wrs.sto will terminate when the duration elapses, wrs.nto, depending on configuration, will either just keep waiting or an ILL exception will be raised. Linux will use wrs.nto, so if platforms have an implementation which falls in the "just keep waiting" category (which is not expected), then it should _not_ advertise Zawrs in the hardware description. Like wfi (and with the same {m,h}status bits to configure it), when wrs.nto is configured to raise exceptions it's expected that the higher privilege level will see the instruction was a wait instruction, do something, and then resume execution following the instruction. For example, KVM does configure exceptions for wfi (hstatus.VTW=1) and therefore also for wrs.nto. KVM does this for wfi since it's better to allow other tasks to be scheduled while a VCPU waits for an interrupt. For waits such as those where wrs.nto/sto would be used, which are typically locks, it is also a good idea for KVM to be involved, as it can attempt to schedule the lock holding VCPU. This series starts with Christoph's addition of the riscv smp_cond_load_relaxed function which applies wrs.sto when available. That patch has been reworked to use wrs.nto and to use the same approach as Arm for the wait loop, since we can't have arbitrary C code between the load-reserved and the wrs. Then, hwprobe support is added (since the instructions are also usable from usermode), and finally KVM is taught about wrs.nto, allowing guests to see and use the Zawrs extension. We still don't have test results from hardware, and it's not possible to prove that using Zawrs is a win when testing on QEMU, not even when oversubscribing VCPUs to guests. However, it is possible to use KVM selftests to force a scenario where we can prove Zawrs does its job and does it well. [4] is a test which does this and, on my machine, without Zawrs it takes 16 seconds to complete and with Zawrs it takes 0.25 seconds. This series is also available here [1]. In order to use QEMU for testing a build with [2] is needed. In order to enable guests to use Zawrs with KVM using kvmtool, the branch at [3] may be used. [1] https://github.com/jones-drew/linux/commits/riscv/zawrs-v3/ [2] https://lore.kernel.org/all/20240312152901.512001-2-ajones@ventanamicro.com/ [3] https://github.com/jones-drew/kvmtool/commits/riscv/zawrs/ [4] https://github.com/jones-drew/linux/commit/cb2beccebcece10881db842ed69bdd5715cfab5d Link: https://lore.kernel.org/r/20240426100820.14762-8-ajones@ventanamicro.com * b4-shazam-merge: KVM: riscv: selftests: Add Zawrs extension to get-reg-list test KVM: riscv: Support guest wrs.nto riscv: hwprobe: export Zawrs ISA extension riscv: Add Zawrs support for spinlocks dt-bindings: riscv: Add Zawrs ISA extension description riscv: Provide a definition for 'pause' Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| | * riscv: hwprobe: export Zawrs ISA extensionAndrew Jones2024-07-121-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Export Zawrs ISA extension through hwprobe. [Palmer: there's a gap in the numbers here as there will be a merge conflict when this is picked up. To avoid confusion I just set the hwprobe ID to match what it would be post-merge.] Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Clément Léger <cleger@rivosinc.com> Link: https://lore.kernel.org/r/20240426100820.14762-12-ajones@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| * | riscv: hwprobe: export highest virtual userspace addressClément Léger2024-07-111-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some userspace applications (OpenJDK for instance) uses the free MSBs in pointers to insert additional information for their own logic and need to get this information from somewhere. Currently they rely on parsing /proc/cpuinfo "mmu=svxx" string to obtain the current value of virtual address usable bits [1]. Since this reflect the raw supported MMU mode, it might differ from the logical one used internally which is why arch_get_mmap_end() is used. Exporting the highest mmapable address through hwprobe will allow a more stable interface to be used. For that purpose, add a new hwprobe key named RISCV_HWPROBE_KEY_HIGHEST_VIRT_ADDRESS which will export the highest userspace virtual address. Link: https://github.com/openjdk/jdk/blob/master/src/hotspot/os_cpu/linux_riscv/vm_version_linux_riscv.cpp#L171 [1] Signed-off-by: Clément Léger <cleger@rivosinc.com> Reviewed-by: Charlie Jenkins <charlie@rivosinc.com> Link: https://lore.kernel.org/r/20240410144558.1104006-1-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| * | riscv: hwprobe: export Zcmop ISA extensionClément Léger2024-06-261-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | Export Zcmop ISA extension through hwprobe. Signed-off-by: Clément Léger <cleger@rivosinc.com> Reviewed-by: Evan Green <evan@rivosinc.com> Link: https://lore.kernel.org/r/20240619113529.676940-15-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| * | riscv: hwprobe: export Zca, Zcf, Zcd and Zcb ISA extensionsClément Léger2024-06-261-0/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | Export Zca, Zcf, Zcd and Zcb ISA extension through hwprobe. Signed-off-by: Clément Léger <cleger@rivosinc.com> Reviewed-by: Charlie Jenkins <charlie@rivosinc.com> Link: https://lore.kernel.org/r/20240619113529.676940-10-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| * | riscv: hwprobe: export Zimop ISA extensionClément Léger2024-06-261-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | Export Zimop ISA extension through hwprobe. Signed-off-by: Clément Léger <cleger@rivosinc.com> Reviewed-by: Charlie Jenkins <charlie@rivosinc.com> Link: https://lore.kernel.org/r/20240619113529.676940-4-cleger@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>