mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2026-06-21 15:43:21 +02:00
Linus Torvalds
23b5d045ae
Pull tracing updates from Steven Rostedt: - Remove a redundant IS_ERR() check trace_pipe_open() already checks for IS_ERR() and does it again in the return path. Remove the return check. - Export seq_buf_putmem_hex() to allow kunit tests against them To add Kunit tests on seq_buf_putmem_hex(), it needs to be exported. - Replace strcat() and strcpy() with seq_buf() logic The code for synthetic events uses a series of strcat() and strcpy() which can be error prone. Replace them with seq_buf() logic that does all the necessary bound checking. - Add a lockdep rcu_is_watching() to trace_##event##_enabled() call The trace_##event##_enabled() is a static branch that is true if the "event" is enabled. But this can hide bugs if this logic is in a location where RCU is disabled and not "watching". It would only trigger if lockdep is enabled and the event is enabled. Add a "rcu_is_watching()" warning if lockdep is enabled in that helper function to trigger regardless if the event is enabled or not. - Remove the local variable in the trace_printk() macro For name space integrity, remove the _______STR variable in the trace_printk() macro for using the sizeof() macro directly. - Use guard()s for the trace_recursion_record.c file - Fix typo in a comment of eventfs_callback() kerneldoc - Use trace_call__##event() in events within trace_##event##_enabled() A couple of events are called within an if block guarded by trace_##event##_enabled(). That is a static key that is only enabled when the event is enabled. The trace_call_##event() calls the tracepoint code directly without adding a redundant static key for that check. - Allow perf to read synthetic events Currently, perf does not have the ability to enable a synthetic event. If it does, it will either cause a kernel warning or error with "No such device". Synthetic events are not much different than kprobes and perf can handle fine with a few modifications. - Replace printk(KERN_WARNING ...) with pr_warn() - Replace krealloc() on an array with krealloc_array() - Fix README file path name for synthetic events - Change tracing_map tracing_map_array to use a flexible array Instead of allocating a separate pointer to hold the pages field of tracing_map_array, allocate the pages field as a flexible array when allocating the structure. - Fold trace_iterator_increment() into trace_find_next_entry_inc() The function trace_iterator_increment() was only used by trace_find_next_entry_inc(). It's not big enough to be a helper function for one user. Fold it into its caller. - Make field_var_str field a flexible array of hist_elt_data Instead of allocating a separate pointer for the field_var_str array of the hist_elt_data structure, allocate it as a flexible array when allocating the structure. - Disable KCOV for trace_irqsoff.c Like trace_preemptirq.c, trace_irqsoff.c has code that will crash when KCOV is enabled on ARM. The irqsoff tracing can be called on ARM because the irqsoff tracing code can be run from early interrupt code and produce coverage unrelated to syscall inputs. - Fix warning in __unregister_ftrace_function() called by perf Perf calls unregister_ftrace_function() without checking if its ftrace_ops has already been unregistered. There's an error path where on clean up it will unregister the ftrace_ops even if it wasn't registered and causes a warning. * tag 'trace-v7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: perf/ftrace: Fix WARNING in __unregister_ftrace_function tracing: Disable KCOV instrumentation for trace_irqsoff.o tracing: Turn hist_elt_data field_var_str into a flexible array tracing: Move trace_iterator_increment() into trace_find_next_entry_inc() tracing: Simplify pages allocation for tracing_map logic tracing: Fix README path for synthetic_events tracing: Use krealloc_array() for trace option array growth tracing/branch: Use pr_warn() instead of printk(KERN_WARNING) tracing: Allow perf to read synthetic events HID: Use trace_call__##name() at guarded tracepoint call sites cpufreq: amd-pstate: Use trace_call__##name() at guarded tracepoint call site tracefs: Fix typo in a comment of eventfs_callback() kerneldoc tracing: Switch trace_recursion_record.c code over to use guard() tracing: Remove local variable for argument detection from trace_printk() tracepoint: Add lockdep rcu_is_watching() check to trace_##name##_enabled() tracing: Bound synthetic-field strings with seq_buf seq_buf: Export seq_buf_putmem_hex() and add KUnit tests tracing: Remove redundant IS_ERR() check in trace_pipe_open()
Linux kernel ============ The Linux kernel is the core of any Linux operating system. It manages hardware, system resources, and provides the fundamental services for all other software. Quick Start ----------- * Report a bug: See Documentation/admin-guide/reporting-issues.rst * Get the latest kernel: https://kernel.org * Build the kernel: See Documentation/admin-guide/quickly-build-trimmed-linux.rst * Join the community: https://lore.kernel.org/ Essential Documentation ----------------------- All users should be familiar with: * Building requirements: Documentation/process/changes.rst * Code of Conduct: Documentation/process/code-of-conduct.rst * License: See COPYING Documentation can be built with make htmldocs or viewed online at: https://www.kernel.org/doc/html/latest/ Who Are You? ============ Find your role below: * New Kernel Developer - Getting started with kernel development * Academic Researcher - Studying kernel internals and architecture * Security Expert - Hardening and vulnerability analysis * Backport/Maintenance Engineer - Maintaining stable kernels * System Administrator - Configuring and troubleshooting * Maintainer - Leading subsystems and reviewing patches * Hardware Vendor - Writing drivers for new hardware * Distribution Maintainer - Packaging kernels for distros * AI Coding Assistant - LLMs and AI-powered development tools For Specific Users ================== New Kernel Developer -------------------- Welcome! Start your kernel development journey here: * Getting Started: Documentation/process/development-process.rst * Your First Patch: Documentation/process/submitting-patches.rst * Coding Style: Documentation/process/coding-style.rst * Build System: Documentation/kbuild/index.rst * Development Tools: Documentation/dev-tools/index.rst * Kernel Hacking Guide: Documentation/kernel-hacking/hacking.rst * Core APIs: Documentation/core-api/index.rst Academic Researcher ------------------- Explore the kernel's architecture and internals: * Researcher Guidelines: Documentation/process/researcher-guidelines.rst * Memory Management: Documentation/mm/index.rst * Scheduler: Documentation/scheduler/index.rst * Networking Stack: Documentation/networking/index.rst * Filesystems: Documentation/filesystems/index.rst * RCU (Read-Copy Update): Documentation/RCU/index.rst * Locking Primitives: Documentation/locking/index.rst * Power Management: Documentation/power/index.rst Security Expert --------------- Security documentation and hardening guides: * Security Documentation: Documentation/security/index.rst * LSM Development: Documentation/security/lsm-development.rst * Self Protection: Documentation/security/self-protection.rst * Reporting Vulnerabilities: Documentation/process/security-bugs.rst * CVE Procedures: Documentation/process/cve.rst * Embargoed Hardware Issues: Documentation/process/embargoed-hardware-issues.rst * Security Features: Documentation/userspace-api/seccomp_filter.rst Backport/Maintenance Engineer ----------------------------- Maintain and stabilize kernel versions: * Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst * Backporting Guide: Documentation/process/backporting.rst * Applying Patches: Documentation/process/applying-patches.rst * Subsystem Profile: Documentation/maintainer/maintainer-entry-profile.rst * Git for Maintainers: Documentation/maintainer/configure-git.rst System Administrator -------------------- Configure, tune, and troubleshoot Linux systems: * Admin Guide: Documentation/admin-guide/index.rst * Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst * Sysctl Tuning: Documentation/admin-guide/sysctl/index.rst * Tracing/Debugging: Documentation/trace/index.rst * Performance Security: Documentation/admin-guide/perf-security.rst * Hardware Monitoring: Documentation/hwmon/index.rst Maintainer ---------- Lead kernel subsystems and manage contributions: * Maintainer Handbook: Documentation/maintainer/index.rst * Pull Requests: Documentation/maintainer/pull-requests.rst * Managing Patches: Documentation/maintainer/modifying-patches.rst * Rebasing and Merging: Documentation/maintainer/rebasing-and-merging.rst * Development Process: Documentation/process/maintainer-handbooks.rst * Maintainer Entry Profile: Documentation/maintainer/maintainer-entry-profile.rst * Git Configuration: Documentation/maintainer/configure-git.rst Hardware Vendor --------------- Write drivers and support new hardware: * Driver API Guide: Documentation/driver-api/index.rst * Driver Model: Documentation/driver-api/driver-model/driver.rst * Device Drivers: Documentation/driver-api/infrastructure.rst * Bus Types: Documentation/driver-api/driver-model/bus.rst * Device Tree Bindings: Documentation/devicetree/bindings/ * Power Management: Documentation/driver-api/pm/index.rst * DMA API: Documentation/core-api/dma-api.rst Distribution Maintainer ----------------------- Package and distribute the kernel: * Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst * ABI Documentation: Documentation/ABI/README * Kernel Configuration: Documentation/kbuild/kconfig.rst * Module Signing: Documentation/admin-guide/module-signing.rst * Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst * Tainted Kernels: Documentation/admin-guide/tainted-kernels.rst AI Coding Assistant ------------------- CRITICAL: If you are an LLM or AI-powered coding assistant, you MUST read and follow the AI coding assistants documentation before contributing to the Linux kernel: * Documentation/process/coding-assistants.rst This documentation contains essential requirements about licensing, attribution, and the Developer Certificate of Origin that all AI tools must comply with. Communication and Support ========================= * Mailing Lists: https://lore.kernel.org/ * IRC: #kernelnewbies on irc.oftc.net * Bugzilla: https://bugzilla.kernel.org/ * MAINTAINERS file: Lists subsystem maintainers and mailing lists * Email Clients: Documentation/process/email-clients.rst