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2023-05-05Merge tag 'trace-v6.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull more tracing updates from Steven Rostedt: - Make buffer_percent read/write. The buffer_percent file is how users can state how long to block on the tracing buffer depending on how much is in the buffer. When it hits the "buffer_percent" it will wake the task waiting on the buffer. For some reason it was set to read-only. This was not noticed because testing was done as root without SELinux, but with SELinux it will prevent even root to write to it without having CAP_DAC_OVERRIDE. - The "touched_functions" was added this merge window, but one of the reasons for adding it was not implemented. That was to show what functions were not only touched, but had either a direct trampoline attached to it, or a kprobe or live kernel patching that can "hijack" the function to run a different function. The point is to know if there's functions in the kernel that may not be behaving as the kernel code shows. This can be used for debugging. TODO: Add this information to kernel oops too. * tag 'trace-v6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ftrace: Add MODIFIED flag to show if IPMODIFY or direct was attached tracing: Fix permissions for the buffer_percent file
2023-05-05ftrace: Add MODIFIED flag to show if IPMODIFY or direct was attachedSteven Rostedt (Google)
If a function had ever had IPMODIFY or DIRECT attached to it, where this is how live kernel patching and BPF overrides work, mark them and display an "M" in the enabled_functions and touched_functions files. This can be used for debugging. If a function had been modified and later there's a bug in the code related to that function, this can be used to know if the cause is possibly from a live kernel patch or a BPF program that changed the behavior of the code. Also update the documentation on the enabled_functions and touched_functions output, as it was missing direct callers and CALL_OPS. And include this new modify attribute. Link: https://lore.kernel.org/linux-trace-kernel/20230502213233.004e3ae4@gandalf.local.home Cc: Mark Rutland <mark.rutland@arm.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-04-28Merge tag 'trace-v6.4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing updates from Steven Rostedt: - User events are finally ready! After lots of collaboration between various parties, we finally locked down on a stable interface for user events that can also work with user space only tracing. This is implemented by telling the kernel (or user space library, but that part is user space only and not part of this patch set), where the variable is that the application uses to know if something is listening to the trace. There's also an interface to tell the kernel about these events, which will show up in the /sys/kernel/tracing/events/user_events/ directory, where it can be enabled. When it's enabled, the kernel will update the variable, to tell the application to start writing to the kernel. See https://lwn.net/Articles/927595/ - Cleaned up the direct trampolines code to simplify arm64 addition of direct trampolines. Direct trampolines use the ftrace interface but instead of jumping to the ftrace trampoline, applications (mostly BPF) can register their own trampoline for performance reasons. - Some updates to the fprobe infrastructure. fprobes are more efficient than kprobes, as it does not need to save all the registers that kprobes on ftrace do. More work needs to be done before the fprobes will be exposed as dynamic events. - More updates to references to the obsolete path of /sys/kernel/debug/tracing for the new /sys/kernel/tracing path. - Add a seq_buf_do_printk() helper to seq_bufs, to print a large buffer line by line instead of all at once. There are users in production kernels that have a large data dump that originally used printk() directly, but the data dump was larger than what printk() allowed as a single print. Using seq_buf() to do the printing fixes that. - Add /sys/kernel/tracing/touched_functions that shows all functions that was every traced by ftrace or a direct trampoline. This is used for debugging issues where a traced function could have caused a crash by a bpf program or live patching. - Add a "fields" option that is similar to "raw" but outputs the fields of the events. It's easier to read by humans. - Some minor fixes and clean ups. * tag 'trace-v6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (41 commits) ring-buffer: Sync IRQ works before buffer destruction tracing: Add missing spaces in trace_print_hex_seq() ring-buffer: Ensure proper resetting of atomic variables in ring_buffer_reset_online_cpus recordmcount: Fix memory leaks in the uwrite function tracing/user_events: Limit max fault-in attempts tracing/user_events: Prevent same address and bit per process tracing/user_events: Ensure bit is cleared on unregister tracing/user_events: Ensure write index cannot be negative seq_buf: Add seq_buf_do_printk() helper tracing: Fix print_fields() for __dyn_loc/__rel_loc tracing/user_events: Set event filter_type from type ring-buffer: Clearly check null ptr returned by rb_set_head_page() tracing: Unbreak user events tracing/user_events: Use print_format_fields() for trace output tracing/user_events: Align structs with tabs for readability tracing/user_events: Limit global user_event count tracing/user_events: Charge event allocs to cgroups tracing/user_events: Update documentation for ABI tracing/user_events: Use write ABI in example tracing/user_events: Add ABI self-test ...
2023-04-20docs: trace: Fix typo in ftrace.rstLin Yu Chen
There is a typo in the sentence "A kernel developer must be conscience ...". The word conscience should be conscious. This patch fixes it. Signed-off-by: Lin Yu Chen <starpt.official@gmail.com> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20230412183739.89894-1-starpt.official@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-03-29tracing/user_events: Update documentation for ABIBeau Belgrave
The ABI for user_events has changed from mmap() based to remote writes. Update the documentation to reflect these changes, add new section for unregistering events since lifetime is now tied to tasks instead of files. Link: https://lkml.kernel.org/r/20230328235219.203-10-beaub@linux.microsoft.com Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-03-29tracing: Add "fields" option to show raw trace event fieldsSteven Rostedt (Google)
The hex, raw and bin formats come from the old PREEMPT_RT patch set latency tracer. That actually gave real alternatives to reading the ascii buffer. But they have started to bit rot and they do not give a good representation of the tracing data. Add "fields" option that will read the trace event fields and parse the data from how the fields are defined: With "fields" = 0 (default) echo 1 > events/sched/sched_switch/enable cat trace <idle>-0 [003] d..2. 540.078653: sched_switch: prev_comm=swapper/3 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=kworker/3:1 next_pid=83 next_prio=120 kworker/3:1-83 [003] d..2. 540.078860: sched_switch: prev_comm=kworker/3:1 prev_pid=83 prev_prio=120 prev_state=I ==> next_comm=swapper/3 next_pid=0 next_prio=120 <idle>-0 [003] d..2. 540.206423: sched_switch: prev_comm=swapper/3 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=sshd next_pid=807 next_prio=120 sshd-807 [003] d..2. 540.206531: sched_switch: prev_comm=sshd prev_pid=807 prev_prio=120 prev_state=S ==> next_comm=swapper/3 next_pid=0 next_prio=120 <idle>-0 [001] d..2. 540.206597: sched_switch: prev_comm=swapper/1 prev_pid=0 prev_prio=120 prev_state=R ==> next_comm=kworker/u16:4 next_pid=58 next_prio=120 kworker/u16:4-58 [001] d..2. 540.206617: sched_switch: prev_comm=kworker/u16:4 prev_pid=58 prev_prio=120 prev_state=I ==> next_comm=bash next_pid=830 next_prio=120 bash-830 [001] d..2. 540.206678: sched_switch: prev_comm=bash prev_pid=830 prev_prio=120 prev_state=R ==> next_comm=kworker/u16:4 next_pid=58 next_prio=120 kworker/u16:4-58 [001] d..2. 540.206696: sched_switch: prev_comm=kworker/u16:4 prev_pid=58 prev_prio=120 prev_state=I ==> next_comm=bash next_pid=830 next_prio=120 bash-830 [001] d..2. 540.206713: sched_switch: prev_comm=bash prev_pid=830 prev_prio=120 prev_state=R ==> next_comm=kworker/u16:4 next_pid=58 next_prio=120 echo 1 > options/fields <...>-998 [002] d..2. 538.643732: sched_switch: next_prio=0x78 (120) next_pid=0x0 (0) next_comm=swapper/2 prev_state=0x20 (32) prev_prio=0x78 (120) prev_pid=0x3e6 (998) prev_comm=trace-cmd <idle>-0 [001] d..2. 538.643806: sched_switch: next_prio=0x78 (120) next_pid=0x33e (830) next_comm=bash prev_state=0x0 (0) prev_prio=0x78 (120) prev_pid=0x0 (0) prev_comm=swapper/1 bash-830 [001] d..2. 538.644106: sched_switch: next_prio=0x78 (120) next_pid=0x3a (58) next_comm=kworker/u16:4 prev_state=0x0 (0) prev_prio=0x78 (120) prev_pid=0x33e (830) prev_comm=bash kworker/u16:4-58 [001] d..2. 538.644130: sched_switch: next_prio=0x78 (120) next_pid=0x33e (830) next_comm=bash prev_state=0x80 (128) prev_prio=0x78 (120) prev_pid=0x3a (58) prev_comm=kworker/u16:4 bash-830 [001] d..2. 538.644180: sched_switch: next_prio=0x78 (120) next_pid=0x3a (58) next_comm=kworker/u16:4 prev_state=0x0 (0) prev_prio=0x78 (120) prev_pid=0x33e (830) prev_comm=bash kworker/u16:4-58 [001] d..2. 538.644185: sched_switch: next_prio=0x78 (120) next_pid=0x33e (830) next_comm=bash prev_state=0x80 (128) prev_prio=0x78 (120) prev_pid=0x3a (58) prev_comm=kworker/u16:4 bash-830 [001] d..2. 538.644204: sched_switch: next_prio=0x78 (120) next_pid=0x0 (0) next_comm=swapper/1 prev_state=0x1 (1) prev_prio=0x78 (120) prev_pid=0x33e (830) prev_comm=bash <idle>-0 [003] d..2. 538.644211: sched_switch: next_prio=0x78 (120) next_pid=0x327 (807) next_comm=sshd prev_state=0x0 (0) prev_prio=0x78 (120) prev_pid=0x0 (0) prev_comm=swapper/3 sshd-807 [003] d..2. 538.644340: sched_switch: next_prio=0x78 (120) next_pid=0x0 (0) next_comm=swapper/3 prev_state=0x1 (1) prev_prio=0x78 (120) prev_pid=0x327 (807) prev_comm=sshd It traces the data safely without using the trace print formatting. Link: https://lore.kernel.org/linux-trace-kernel/20230328145156.497651be@gandalf.local.home Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-03-28docs: tracing: Update fprobe documentationMasami Hiramatsu (Google)
Update fprobe.rst for - the private entry_data argument - the return value of the entry handler - the nr_rethook_node field. Link: https://lkml.kernel.org/r/167526701579.433354.3057889264263546659.stgit@mhiramat.roam.corp.google.com Cc: Florent Revest <revest@chromium.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-02-24Merge tag 'char-misc-6.3-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc and other driver subsystem updates from Greg KH: "Here is the large set of driver changes for char/misc drivers and other smaller driver subsystems that flow through this git tree. Included in here are: - New IIO drivers and features and improvments in that subsystem - New hwtracing drivers and additions to that subsystem - lots of interconnect changes and new drivers as that subsystem seems under very active development recently. This required also merging in the icc subsystem changes through this tree. - FPGA driver updates - counter subsystem and driver updates - MHI driver updates - nvmem driver updates - documentation updates - Other smaller driver updates and fixes, full details in the shortlog All of these have been in linux-next for a while with no reported problems" * tag 'char-misc-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (223 commits) scripts/tags.sh: fix incompatibility with PCRE2 firmware: coreboot: Remove GOOGLE_COREBOOT_TABLE_ACPI/OF Kconfig entries mei: lower the log level for non-fatal failed messages mei: bus: disallow driver match while dismantling device misc: vmw_balloon: fix memory leak with using debugfs_lookup() nvmem: stm32: fix OPTEE dependency dt-bindings: nvmem: qfprom: add IPQ8074 compatible nvmem: qcom-spmi-sdam: register at device init time nvmem: rave-sp-eeprm: fix kernel-doc bad line warning nvmem: stm32: detect bsec pta presence for STM32MP15x nvmem: stm32: add OP-TEE support for STM32MP13x nvmem: core: use nvmem_add_one_cell() in nvmem_add_cells_from_of() nvmem: core: add nvmem_add_one_cell() nvmem: core: drop the removal of the cells in nvmem_add_cells() nvmem: core: move struct nvmem_cell_info to nvmem-provider.h nvmem: core: add an index parameter to the cell of: property: add #nvmem-cell-cells property of: property: make #.*-cells optional for simple props of: base: add of_parse_phandle_with_optional_args() net: add helper eth_addr_add() ...
2023-02-23Merge tag 'probes-v6.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull kprobes updates from Masami Hiramatsu: - Skip negative return code check for snprintf in eprobe - Add recursive call test cases for kprobe unit test - Add 'char' type to probe events to show it as the character instead of value - Update kselftest kprobe-event testcase to ignore '__pfx_' symbols - Fix kselftest to check filter on eprobe event correctly - Add filter on eprobe to the README file in tracefs - Fix optprobes to check whether there is 'under unoptimizing' optprobe when optimizing another kprobe correctly - Fix optprobe to check whether there is 'under unoptimizing' optprobe when fetching the original instruction correctly - Fix optprobe to free 'forcibly unoptimized' optprobe correctly * tag 'probes-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing/eprobe: no need to check for negative ret value for snprintf test_kprobes: Add recursed kprobe test case tracing/probe: add a char type to show the character value of traced arguments selftests/ftrace: Fix probepoint testcase to ignore __pfx_* symbols selftests/ftrace: Fix eprobe syntax test case to check filter support tracing/eprobe: Fix to add filter on eprobe description in README file x86/kprobes: Fix arch_check_optimized_kprobe check within optimized_kprobe range x86/kprobes: Fix __recover_optprobed_insn check optimizing logic kprobes: Fix to handle forcibly unoptimized kprobes on freeing_list
2023-02-23Merge tag 'trace-v6.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing updates from Steven Rostedt: - Add function names as a way to filter function addresses - Add sample module to test ftrace ops and dynamic trampolines - Allow stack traces to be passed from beginning event to end event for synthetic events. This will allow seeing the stack trace of when a task is scheduled out and recorded when it gets scheduled back in. - Add trace event helper __get_buf() to use as a temporary buffer when printing out trace event output. - Add kernel command line to create trace instances on boot up. - Add enabling of events to instances created at boot up. - Add trace_array_puts() to write into instances. - Allow boot instances to take a snapshot at the end of boot up. - Allow live patch modules to include trace events - Minor fixes and clean ups * tag 'trace-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (31 commits) tracing: Remove unnecessary NULL assignment tracepoint: Allow livepatch module add trace event tracing: Always use canonical ftrace path tracing/histogram: Fix stacktrace histogram Documententation tracing/histogram: Fix stacktrace key tracing/histogram: Fix a few problems with stacktrace variable printing tracing: Add BUILD_BUG() to make sure stacktrace fits in strings tracing/histogram: Don't use strlen to find length of stacktrace variables tracing: Allow boot instances to have snapshot buffers tracing: Add trace_array_puts() to write into instance tracing: Add enabling of events to boot instances tracing: Add creation of instances at boot command line tracing: Fix trace_event_raw_event_synth() if else statement samples: ftrace: Make some global variables static ftrace: sample: avoid open-coded 64-bit division samples: ftrace: Include the nospec-branch.h only for x86 tracing: Acquire buffer from temparary trace sequence tracing/histogram: Wrap remaining shell snippets in code blocks tracing/osnoise: No need for schedule_hrtimeout range bpf/tracing: Use stage6 of tracing to not duplicate macros ...
2023-02-21tracing/probe: add a char type to show the character value of traced argumentsDonglin Peng
There are scenes that we want to show the character value of traced arguments other than a decimal or hexadecimal or string value for debug convinience. I add a new type named 'char' to do it and a new test case file named 'kprobe_args_char.tc' to do selftest for char type. For example: The to be traced function is 'void demo_func(char type, char *name);', we can add a kprobe event as follows to show argument values as we want: echo 'p:myprobe demo_func $arg1:char +0($arg2):char[5]' > kprobe_events we will get the following trace log: ... myprobe: (demo_func+0x0/0x29) arg1='A' arg2={'b','p','f','1',''} Link: https://lore.kernel.org/all/20221219110613.367098-1-dolinux.peng@gmail.com/ Signed-off-by: Donglin Peng <dolinux.peng@gmail.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-02-16tracing/histogram: Fix stacktrace histogram DocumententationTom Zanussi
Fix a small problem with the histogram specification in the Documentation, and change the example to show output using a stacktrace field rather than the global stacktrace. Link: https://lkml.kernel.org/r/f75f807dd4998249e513515f703a2ff7407605f4.1676063532.git.zanussi@kernel.org Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-02-07tracing/histogram: Wrap remaining shell snippets in code blocksBagas Sanjaya
Most shell command snippets (echo/cat) and their output are already in literal code blocks. However a few still isn't wrapped, in which the htmldocs output is ugly. Wrap the remaining unwrapped snippets, while also fix recent kernel test robot warnings. Link: https://lore.kernel.org/linux-trace-kernel/20230129031402.47420-1-bagasdotme@gmail.com Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/linux-doc/202301290253.LU5yIxcJ-lkp@intel.com/ Fixes: 88238513bb2671 ("tracing/histogram: Document variable stacktrace") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-01-31docs: ftrace: always use canonical ftrace pathRoss Zwisler
The canonical location for the tracefs filesystem is at /sys/kernel/tracing. But, from Documentation/trace/ftrace.rst: Before 4.1, all ftrace tracing control files were within the debugfs file system, which is typically located at /sys/kernel/debug/tracing. For backward compatibility, when mounting the debugfs file system, the tracefs file system will be automatically mounted at: /sys/kernel/debug/tracing Many parts of Documentation still reference this older debugfs path, so let's update them to avoid confusion. Signed-off-by: Ross Zwisler <zwisler@google.com> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20230125213251.2013791-1-zwisler@google.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-01-25tracing/histogram: Document variable stacktraceSteven Rostedt (Google)
Add a little documentation (and a useful example) of how a stacktrace can be used within a histogram variable and synthetic event. Link: https://lkml.kernel.org/r/20230117152236.320181354@goodmis.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tom Zanussi <zanussi@kernel.org> Cc: Ross Zwisler <zwisler@google.com> Cc: Ching-lin Yu <chinglinyu@google.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-01-25tracing: Add a way to filter function addresses to function namesSteven Rostedt (Google)
There's been several times where an event records a function address in its field and I needed to filter on that address for a specific function name. It required looking up the function in kallsyms, finding its size, and doing a compare of "field >= function_start && field < function_end". But this would change from boot to boot and is unreliable in scripts. Also, it is useful to have this at boot up, where the addresses will not be known. For example, on the boot command line: trace_trigger="initcall_finish.traceoff if func.function == acpi_init" To implement this, add a ".function" prefix, that will check that the field is of size long, and the only operations allowed (so far) are "==" and "!=". Link: https://lkml.kernel.org/r/20221219183213.916833763@goodmis.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tom Zanussi <zanussi@kernel.org> Cc: Zheng Yejian <zhengyejian1@huawei.com> Reviewed-by: Ross Zwisler <zwisler@google.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-01-24Documentation: kprobetrace: Split paragraphsYoann Congal
Add an empty line to force the output to split paragraphs like it is splitin the REST source. Signed-off-by: Yoann Congal <yoann.congal@smile.fr> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Link: https://lore.kernel.org/r/20230121225304.1711635-4-yoann.congal@smile.fr Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-01-24Documentation: kprobetrace: Fix code block markupYoann Congal
This display the following code extract as a code block instead of a normal paragraph. Signed-off-by: Yoann Congal <yoann.congal@smile.fr> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Link: https://lore.kernel.org/r/20230121225304.1711635-3-yoann.congal@smile.fr Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-01-24Documentation: kprobetrace: Fix some typosYoann Congal
* Uncapitalise tracepoint * Hyphen in *-based * Plurals * fetch-args -> fetchargs * 2bytes hex -> 2-byte hex * .. -> . * arch -> architecture Signed-off-by: Yoann Congal <yoann.congal@smile.fr> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Link: https://lore.kernel.org/r/20230121225304.1711635-2-yoann.congal@smile.fr Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2023-01-23Documentation: coresight: tpdm: Add dummy comment after sysfs listBagas Sanjaya
kernel test robot reported htmldocs warning: Documentation/trace/coresight/coresight-tpdm.rst:43: WARNING: Document may not end with a transition. Since there is no more documentation left for TPDM, fix the warning by adding dummy comment, thus creating the required text transition. Link: https://lore.kernel.org/linux-doc/202301210955.zYxDrLgv-lkp@intel.com/ Fixes: 758d638667d474 ("Documentation: trace: Add documentation for TPDM and TPDA") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Link: https://lore.kernel.org/r/20230121040015.28139-3-bagasdotme@gmail.com
2023-01-23Documentation: coresight: Extend title heading syntax in TPDM and TPDA ↵Bagas Sanjaya
documentation kernel test robot reported htmldocs warnings: Documentation/trace/coresight/coresight-tpda.rst:3: WARNING: Title overline too short. Documentation/trace/coresight/coresight-tpdm.rst:3: WARNING: Title overline too short. Extend title heading syntax (overline and underline) to match title text to fix these warnings. While at it, trim unneeded period in the title text. Link: https://lore.kernel.org/linux-doc/202301210955.zYxDrLgv-lkp@intel.com/ Fixes: 758d638667d474 ("Documentation: trace: Add documentation for TPDM and TPDA") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Link: https://lore.kernel.org/r/20230121040015.28139-2-bagasdotme@gmail.com
2023-01-20Documentation: trace: Add documentation for TPDM and TPDAMao Jinlong
Add documentation for the TPDM and TPDA under trace/coresight. Signed-off-by: Mao Jinlong <quic_jinlmao@quicinc.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Link: https://lore.kernel.org/r/20230117145708.16739-9-quic_jinlmao@quicinc.com
2023-01-16Documentation: Add document for UltraSoc SMB driverQi Liu
Bring in documentation for UltraSoc SMB driver. It simply describes the device, sysfs interface and the firmware bindings. Signed-off-by: Qi Liu <liuqi115@huawei.com> Signed-off-by: Junhao He <hejunhao3@huawei.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Link: https://lore.kernel.org/r/20230114101302.62320-3-hejunhao3@huawei.com
2023-01-02docs: ftrace: fix a issue with duplicated subtitle numberDonglin Peng
The subtitle "5.3 Clearing filters" and "5.3 Subsystem filters" has the same index number, let's fix it. Fixes: 95b696088c1c ("tracing/filters: add filter Documentation") Signed-off-by: Donglin Peng <dolinux.peng@gmail.com> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20221209025119.1371570-1-dolinux.peng@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-12-21Merge tag 'trace-probes-v6.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull trace probes updates from Steven Rostedt: - New "symstr" type for dynamic events that writes the name of the function+offset into the ring buffer and not just the address - Prevent kernel symbol processing on addresses in user space probes (uprobes). - And minor fixes and clean ups * tag 'trace-probes-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing/probes: Reject symbol/symstr type for uprobe tracing/probes: Add symstr type for dynamic events kprobes: kretprobe events missing on 2-core KVM guest kprobes: Fix check for probe enabled in kill_kprobe() test_kprobes: Fix implicit declaration error of test_kprobes tracing: Fix race where eprobes can be called before the event
2022-12-15Merge tag 'trace-v6.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing updates from Steven Rostedt: - Add options to the osnoise tracer: - 'panic_on_stop' option that panics the kernel if osnoise is greater than some user defined threshold. - 'preempt' option, to test noise while preemption is disabled - 'irq' option, to test noise when interrupts are disabled - Add .percent and .graph suffix to histograms to give different outputs - Add nohitcount to disable showing hitcount in histogram output - Add new __cpumask() to trace event fields to annotate that a unsigned long array is a cpumask to user space and should be treated as one. - Add trace_trigger kernel command line parameter to enable trace event triggers at boot up. Useful to trace stack traces, disable tracing and take snapshots. - Fix x86/kmmio mmio tracer to work with the updates to lockdep - Unify the panic and die notifiers - Add back ftrace_expect reference that is used to extract more information in the ftrace_bug() code. - Have trigger filter parsing errors show up in the tracing error log. - Updated MAINTAINERS file to add kernel tracing mailing list and patchwork info - Use IDA to keep track of event type numbers. - And minor fixes and clean ups * tag 'trace-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (44 commits) tracing: Fix cpumask() example typo tracing: Improve panic/die notifiers ftrace: Prevent RCU stall on PREEMPT_VOLUNTARY kernels tracing: Do not synchronize freeing of trigger filter on boot up tracing: Remove pointer (asterisk) and brackets from cpumask_t field tracing: Have trigger filter parsing errors show up in error_log x86/mm/kmmio: Remove redundant preempt_disable() tracing: Fix infinite loop in tracing_read_pipe on overflowed print_trace_line Documentation/osnoise: Add osnoise/options documentation tracing/osnoise: Add preempt and/or irq disabled options tracing/osnoise: Add PANIC_ON_STOP option Documentation/osnoise: Escape underscore of NO_ prefix tracing: Fix some checker warnings tracing/osnoise: Make osnoise_options static tracing: remove unnecessary trace_trigger ifdef ring-buffer: Handle resize in early boot up tracing/hist: Fix issue of losting command info in error_log tracing: Fix issue of missing one synthetic field tracing/hist: Fix out-of-bound write on 'action_data.var_ref_idx' tracing/hist: Fix wrong return value in parse_action_params() ...
2022-12-15tracing/probes: Add symstr type for dynamic eventsMasami Hiramatsu (Google)
Add 'symstr' type for storing the kernel symbol as a string data instead of the symbol address. This allows us to filter the events by wildcard symbol name. e.g. # echo 'e:wqfunc workqueue.workqueue_execute_start symname=$function:symstr' >> dynamic_events # cat events/eprobes/wqfunc/format name: wqfunc ID: 2110 format: field:unsigned short common_type; offset:0; size:2; signed:0; field:unsigned char common_flags; offset:2; size:1; signed:0; field:unsigned char common_preempt_count; offset:3; size:1; signed:0; field:int common_pid; offset:4; size:4; signed:1; field:__data_loc char[] symname; offset:8; size:4; signed:1; print fmt: " symname=\"%s\"", __get_str(symname) Note that there is already 'symbol' type which just change the print format (so it still stores the symbol address in the tracing ring buffer.) On the other hand, 'symstr' type stores the actual "symbol+offset/size" data as a string. Link: https://lore.kernel.org/all/166679930847.1528100.4124308529180235965.stgit@devnote3/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2022-12-15kprobes: kretprobe events missing on 2-core KVM guestwuqiang
Default value of maxactive is set as num_possible_cpus() for nonpreemptable systems. For a 2-core system, only 2 kretprobe instances would be allocated in default, then these 2 instances for execve kretprobe are very likely to be used up with a pipelined command. Here's the testcase: a shell script was added to crontab, and the content of the script is: #!/bin/sh do_something_magic `tr -dc a-z < /dev/urandom | head -c 10` cron will trigger a series of program executions (4 times every hour). Then events loss would be noticed normally after 3-4 hours of testings. The issue is caused by a burst of series of execve requests. The best number of kretprobe instances could be different case by case, and should be user's duty to determine, but num_possible_cpus() as the default value is inadequate especially for systems with small number of cpus. This patch enables the logic for preemption as default, thus increases the minimum of maxactive to 10 for nonpreemptable systems. Link: https://lore.kernel.org/all/20221110081502.492289-1-wuqiang.matt@bytedance.com/ Signed-off-by: wuqiang <wuqiang.matt@bytedance.com> Reviewed-by: Solar Designer <solar@openwall.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2022-12-12Merge tag 'fs.ovl.setgid.v6.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping Pull setgid inheritance updates from Christian Brauner: "This contains the work to make setgid inheritance consistent between modifying a file and when changing ownership or mode as this has been a repeated source of very subtle bugs. The gist is that we perform the same permission checks in the write path as we do in the ownership and mode changing paths after this series where we're currently doing different things. We've already made setgid inheritance a lot more consistent and reliable in the last releases by moving setgid stripping from the individual filesystems up into the vfs. This aims to make the logic even more consistent and easier to understand and also to fix long-standing overlayfs setgid inheritance bugs. Miklos was nice enough to just let me carry the trivial overlayfs patches from Amir too. Below is a more detailed explanation how the current difference in setgid handling lead to very subtle bugs exemplified via overlayfs which is a victim of the current rules. I hope this explains why I think taking the regression risk here is worth it. A long while ago I found a few setgid inheritance bugs in overlayfs in the write path in certain conditions. Amir recently picked this back up in [1] and I jumped on board to fix this more generally. On the surface all that overlayfs would need to fix setgid inheritance would be to call file_remove_privs() or file_modified() but actually that isn't enough because the setgid inheritance api is wildly inconsistent in that area. Before this pr setgid stripping in file_remove_privs()'s old should_remove_suid() helper was inconsistent with other parts of the vfs. Specifically, it only raises ATTR_KILL_SGID if the inode is S_ISGID and S_IXGRP but not if the inode isn't in the caller's groups and the caller isn't privileged over the inode although we require this already in setattr_prepare() and setattr_copy() and so all filesystem implement this requirement implicitly because they have to use setattr_{prepare,copy}() anyway. But the inconsistency shows up in setgid stripping bugs for overlayfs in xfstests (e.g., generic/673, generic/683, generic/685, generic/686, generic/687). For example, we test whether suid and setgid stripping works correctly when performing various write-like operations as an unprivileged user (fallocate, reflink, write, etc.): echo "Test 1 - qa_user, non-exec file $verb" setup_testfile chmod a+rws $junk_file commit_and_check "$qa_user" "$verb" 64k 64k The test basically creates a file with 6666 permissions. While the file has the S_ISUID and S_ISGID bits set it does not have the S_IXGRP set. On a regular filesystem like xfs what will happen is: sys_fallocate() -> vfs_fallocate() -> xfs_file_fallocate() -> file_modified() -> __file_remove_privs() -> dentry_needs_remove_privs() -> should_remove_suid() -> __remove_privs() newattrs.ia_valid = ATTR_FORCE | kill; -> notify_change() -> setattr_copy() In should_remove_suid() we can see that ATTR_KILL_SUID is raised unconditionally because the file in the test has S_ISUID set. But we also see that ATTR_KILL_SGID won't be set because while the file is S_ISGID it is not S_IXGRP (see above) which is a condition for ATTR_KILL_SGID being raised. So by the time we call notify_change() we have attr->ia_valid set to ATTR_KILL_SUID | ATTR_FORCE. Now notify_change() sees that ATTR_KILL_SUID is set and does: ia_valid = attr->ia_valid |= ATTR_MODE attr->ia_mode = (inode->i_mode & ~S_ISUID); which means that when we call setattr_copy() later we will definitely update inode->i_mode. Note that attr->ia_mode still contains S_ISGID. Now we call into the filesystem's ->setattr() inode operation which will end up calling setattr_copy(). Since ATTR_MODE is set we will hit: if (ia_valid & ATTR_MODE) { umode_t mode = attr->ia_mode; vfsgid_t vfsgid = i_gid_into_vfsgid(mnt_userns, inode); if (!vfsgid_in_group_p(vfsgid) && !capable_wrt_inode_uidgid(mnt_userns, inode, CAP_FSETID)) mode &= ~S_ISGID; inode->i_mode = mode; } and since the caller in the test is neither capable nor in the group of the inode the S_ISGID bit is stripped. But assume the file isn't suid then ATTR_KILL_SUID won't be raised which has the consequence that neither the setgid nor the suid bits are stripped even though it should be stripped because the inode isn't in the caller's groups and the caller isn't privileged over the inode. If overlayfs is in the mix things become a bit more complicated and the bug shows up more clearly. When e.g., ovl_setattr() is hit from ovl_fallocate()'s call to file_remove_privs() then ATTR_KILL_SUID and ATTR_KILL_SGID might be raised but because the check in notify_change() is questioning the ATTR_KILL_SGID flag again by requiring S_IXGRP for it to be stripped the S_ISGID bit isn't removed even though it should be stripped: sys_fallocate() -> vfs_fallocate() -> ovl_fallocate() -> file_remove_privs() -> dentry_needs_remove_privs() -> should_remove_suid() -> __remove_privs() newattrs.ia_valid = ATTR_FORCE | kill; -> notify_change() -> ovl_setattr() /* TAKE ON MOUNTER'S CREDS */ -> ovl_do_notify_change() -> notify_change() /* GIVE UP MOUNTER'S CREDS */ /* TAKE ON MOUNTER'S CREDS */ -> vfs_fallocate() -> xfs_file_fallocate() -> file_modified() -> __file_remove_privs() -> dentry_needs_remove_privs() -> should_remove_suid() -> __remove_privs() newattrs.ia_valid = attr_force | kill; -> notify_change() The fix for all of this is to make file_remove_privs()'s should_remove_suid() helper perform the same checks as we already require in setattr_prepare() and setattr_copy() and have notify_change() not pointlessly requiring S_IXGRP again. It doesn't make any sense in the first place because the caller must calculate the flags via should_remove_suid() anyway which would raise ATTR_KILL_SGID Note that some xfstests will now fail as these patches will cause the setgid bit to be lost in certain conditions for unprivileged users modifying a setgid file when they would've been kept otherwise. I think this risk is worth taking and I explained and mentioned this multiple times on the list [2]. Enforcing the rules consistently across write operations and chmod/chown will lead to losing the setgid bit in cases were it might've been retained before. While I've mentioned this a few times but it's worth repeating just to make sure that this is understood. For the sake of maintainability, consistency, and security this is a risk worth taking. If we really see regressions for workloads the fix is to have special setgid handling in the write path again with different semantics from chmod/chown and possibly additional duct tape for overlayfs. I'll update the relevant xfstests with if you should decide to merge this second setgid cleanup. Before that people should be aware that there might be failures for fstests where unprivileged users modify a setgid file" Link: https://lore.kernel.org/linux-fsdevel/20221003123040.900827-1-amir73il@gmail.com [1] Link: https://lore.kernel.org/linux-fsdevel/20221122142010.zchf2jz2oymx55qi@wittgenstein [2] * tag 'fs.ovl.setgid.v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping: fs: use consistent setgid checks in is_sxid() ovl: remove privs in ovl_fallocate() ovl: remove privs in ovl_copyfile() attr: use consistent sgid stripping checks attr: add setattr_should_drop_sgid() fs: move should_remove_suid() attr: add in_group_or_capable()
2022-12-10Documentation/osnoise: Add osnoise/options documentationDaniel Bristot de Oliveira
Add the documentation about the osnoise/options file, the options, and some additional explanation about the OSNOISE_WORKLOAD option. Link: https://lkml.kernel.org/r/fde5567a4bae364f67fd1e9a644d1d62862618a6.1670623111.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-12-10Documentation/osnoise: Escape underscore of NO_ prefixBagas Sanjaya
kernel test robot reported unknown target name warning: Documentation/trace/osnoise-tracer.rst:112: WARNING: Unknown target name: "no". The warning causes NO_ prefix to be rendered as link text instead, which points to non-existent link target. Escape the prefix underscore to fix the warning. Link: https://lkml.kernel.org/r/20221125034300.24168-1-bagasdotme@gmail.com Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ammar Faizi <ammarfaizi2@gnuweeb.org> Cc: GNU/Weeb Mailing List <gwml@vger.gnuweeb.org> Link: https://lore.kernel.org/linux-doc/202211240447.HxRNftE5-lkp@intel.com/ Fixes: 67543cd6b8eee5 ("Documentation/osnoise: Add osnoise/options documentation") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-12-09tracing: docs: Update histogram doc for .percent/.graph and 'nohitcount'Masami Hiramatsu (Google)
Update histogram document for .percent/.graph suffixes and 'nohitcount' option. Link: https://lore.kernel.org/linux-trace-kernel/166610815604.56030.4124933216911828519.stgit@devnote2 Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Tom Zanussi <zanussi@kernel.org> Tested-by: Tom Zanussi <zanussi@kernel.org>
2022-11-23Documentation/osnoise: Add osnoise/options documentationDaniel Bristot de Oliveira
Add the documentation about the osnoise/options file, along with an explanation about the OSNOISE_WORKLOAD option. Link: https://lkml.kernel.org/r/777af8f3d87beedd304805f98eff6c8291d64226.1668692096.git.bristot@kernel.org Cc: Daniel Bristot de Oliveira <bristot@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-10-18tracing/histogram: Update document for KEYS_MAX sizeZheng Yejian
After commit 4f36c2d85ced ("tracing: Increase tracing map KEYS_MAX size"), 'keys' supports up to three fields. Signed-off-by: Zheng Yejian <zhengyejian1@huawei.com> Cc: stable@vger.kernel.org Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Link: https://lore.kernel.org/r/20221017103806.2479139-1-zhengyejian1@huawei.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-10-18attr: use consistent sgid stripping checksChristian Brauner
Currently setgid stripping in file_remove_privs()'s should_remove_suid() helper is inconsistent with other parts of the vfs. Specifically, it only raises ATTR_KILL_SGID if the inode is S_ISGID and S_IXGRP but not if the inode isn't in the caller's groups and the caller isn't privileged over the inode although we require this already in setattr_prepare() and setattr_copy() and so all filesystem implement this requirement implicitly because they have to use setattr_{prepare,copy}() anyway. But the inconsistency shows up in setgid stripping bugs for overlayfs in xfstests (e.g., generic/673, generic/683, generic/685, generic/686, generic/687). For example, we test whether suid and setgid stripping works correctly when performing various write-like operations as an unprivileged user (fallocate, reflink, write, etc.): echo "Test 1 - qa_user, non-exec file $verb" setup_testfile chmod a+rws $junk_file commit_and_check "$qa_user" "$verb" 64k 64k The test basically creates a file with 6666 permissions. While the file has the S_ISUID and S_ISGID bits set it does not have the S_IXGRP set. On a regular filesystem like xfs what will happen is: sys_fallocate() -> vfs_fallocate() -> xfs_file_fallocate() -> file_modified() -> __file_remove_privs() -> dentry_needs_remove_privs() -> should_remove_suid() -> __remove_privs() newattrs.ia_valid = ATTR_FORCE | kill; -> notify_change() -> setattr_copy() In should_remove_suid() we can see that ATTR_KILL_SUID is raised unconditionally because the file in the test has S_ISUID set. But we also see that ATTR_KILL_SGID won't be set because while the file is S_ISGID it is not S_IXGRP (see above) which is a condition for ATTR_KILL_SGID being raised. So by the time we call notify_change() we have attr->ia_valid set to ATTR_KILL_SUID | ATTR_FORCE. Now notify_change() sees that ATTR_KILL_SUID is set and does: ia_valid = attr->ia_valid |= ATTR_MODE attr->ia_mode = (inode->i_mode & ~S_ISUID); which means that when we call setattr_copy() later we will definitely update inode->i_mode. Note that attr->ia_mode still contains S_ISGID. Now we call into the filesystem's ->setattr() inode operation which will end up calling setattr_copy(). Since ATTR_MODE is set we will hit: if (ia_valid & ATTR_MODE) { umode_t mode = attr->ia_mode; vfsgid_t vfsgid = i_gid_into_vfsgid(mnt_userns, inode); if (!vfsgid_in_group_p(vfsgid) && !capable_wrt_inode_uidgid(mnt_userns, inode, CAP_FSETID)) mode &= ~S_ISGID; inode->i_mode = mode; } and since the caller in the test is neither capable nor in the group of the inode the S_ISGID bit is stripped. But assume the file isn't suid then ATTR_KILL_SUID won't be raised which has the consequence that neither the setgid nor the suid bits are stripped even though it should be stripped because the inode isn't in the caller's groups and the caller isn't privileged over the inode. If overlayfs is in the mix things become a bit more complicated and the bug shows up more clearly. When e.g., ovl_setattr() is hit from ovl_fallocate()'s call to file_remove_privs() then ATTR_KILL_SUID and ATTR_KILL_SGID might be raised but because the check in notify_change() is questioning the ATTR_KILL_SGID flag again by requiring S_IXGRP for it to be stripped the S_ISGID bit isn't removed even though it should be stripped: sys_fallocate() -> vfs_fallocate() -> ovl_fallocate() -> file_remove_privs() -> dentry_needs_remove_privs() -> should_remove_suid() -> __remove_privs() newattrs.ia_valid = ATTR_FORCE | kill; -> notify_change() -> ovl_setattr() // TAKE ON MOUNTER'S CREDS -> ovl_do_notify_change() -> notify_change() // GIVE UP MOUNTER'S CREDS // TAKE ON MOUNTER'S CREDS -> vfs_fallocate() -> xfs_file_fallocate() -> file_modified() -> __file_remove_privs() -> dentry_needs_remove_privs() -> should_remove_suid() -> __remove_privs() newattrs.ia_valid = attr_force | kill; -> notify_change() The fix for all of this is to make file_remove_privs()'s should_remove_suid() helper to perform the same checks as we already require in setattr_prepare() and setattr_copy() and have notify_change() not pointlessly requiring S_IXGRP again. It doesn't make any sense in the first place because the caller must calculate the flags via should_remove_suid() anyway which would raise ATTR_KILL_SGID. While we're at it we move should_remove_suid() from inode.c to attr.c where it belongs with the rest of the iattr helpers. Especially since it returns ATTR_KILL_S{G,U}ID flags. We also rename it to setattr_should_drop_suidgid() to better reflect that it indicates both setuid and setgid bit removal and also that it returns attr flags. Running xfstests with this doesn't report any regressions. We should really try and use consistent checks. Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-10-13Merge tag 'docs-6.1-2' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation fixes from Jonathan Corbet: "A handful of relatively simple documentation fixes, plus a set of patches catching the Chinese translation up with the front-page rework" * tag 'docs-6.1-2' of git://git.lwn.net/linux: Documentation: rtla: Correct command line example docs/zh_CN: add a man-pages link to zh_CN/index.rst docs/zh_CN: Rewrite the Chinese translation front page docs/zh_CN: add zh_CN/arch.rst docs/zh_CN: promote the title of zh_CN/process/index.rst docs/zh_CN: Update the translation of page_owner to 6.0-rc7 docs/zh_CN: Update the translation of ksm to 6.0-rc7 docs/howto: Replace abundoned URL of gmane.org Documentation: ubifs: Fix compression idiom Documentation/mm/page_owner.rst: delete frequently changing experimental data docs/zh_CN: Fix build warning docs: ftrace: Correct access mode
2022-10-11Merge tag 'perf-tools-for-v6.1-1-2022-10-07' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux Pull perf tools updates from Arnaldo Carvalho de Melo: - Add support for AMD on 'perf mem' and 'perf c2c', the kernel enablement patches went via tip. Example: $ sudo perf mem record -- -c 10000 ^C[ perf record: Woken up 227 times to write data ] [ perf record: Captured and wrote 58.760 MB perf.data (836978 samples) ] $ sudo perf mem report -F mem,sample,snoop Samples: 836K of event 'ibs_op//', Event count (approx.): 8418762 Memory access Samples Snoop N/A 700620 N/A L1 hit 126675 N/A L2 hit 424 N/A L3 hit 664 HitM L3 hit 10 N/A Local RAM hit 2 N/A Remote RAM (1 hop) hit 8558 N/A Remote Cache (1 hop) hit 3 N/A Remote Cache (1 hop) hit 2 HitM Remote Cache (2 hops) hit 10 HitM Remote Cache (2 hops) hit 6 N/A Uncached hit 4 N/A $ - "perf lock" improvements: - Add -E/--entries option to limit the number of entries to display, say to ask for just the top 5 contended locks. - Add -q/--quiet option to suppress header and debug messages. - Add a 'perf test' kernel lock contention entry to test 'perf lock'. - "perf lock contention" improvements: - Ask BPF's bpf_get_stackid() to skip some callchain entries. The ones closer to the tooling are bpf related and not that interesting, the ones calling the locking function are the ones we're interested in, example of a full, unskipped callstack: - Allow changing the callstack depth and number of entries to skip. 1 10.74 us 10.74 us 10.74 us spinlock __bpf_trace_contention_begin+0xb 0xffffffffc03b5c47 bpf_prog_bf07ae9e2cbd02c5_contention_begin+0x117 0xffffffffc03b5c47 bpf_prog_bf07ae9e2cbd02c5_contention_begin+0x117 0xffffffffbb8b8e75 bpf_trace_run2+0x35 0xffffffffbb7eab9b __bpf_trace_contention_begin+0xb 0xffffffffbb7ebe75 queued_spin_lock_slowpath+0x1f5 0xffffffffbc1c26ff _raw_spin_lock+0x1f 0xffffffffbb841015 tick_do_update_jiffies64+0x25 0xffffffffbb8409ee tick_irq_enter+0x9e - Show full callstack in verbose mode (-v option), sometimes this is desirable instead of showing just one callstack entry. - Allow multiple time ranges in 'perf record --delay' to help in reducing the amount of data collected from hardware tracing (Intel PT, etc) when there is a rough idea of periods of time where events of interest take time. - Add Intel PT to record only decoder debug messages when error happens. - Improve layout of Intel PT man page. - Add new branch types: alignment, data and inst faults and arch specific ones, such as fiq, debug_halt, debug_exit, debug_inst and debug_data on arm64. Kernel enablement went thru the tip tree. - Fix 'perf probe' error log check in 'perf test' when no debuginfo is available. - Fix 'perf stat' aggregation mode logic, it should be looking at the CPU not at the core number. - Fix flags parsing in 'perf trace' filters. - Introduce compact encoding of CPU range encoding on perf.data, to avoid having a bitmap with all the CPUs. - Improvements to the 'perf stat' metrics, including adding "core_wide", and computing "smt" from the CPU topology. - Add support to the new PERF_FORMAT_LOST perf_event_attr.read_format, that allows tooling to ask for the precise number of lost samples for a given event. - Add 'addr' sort key to see just the address of sampled instructions: $ perf record -o- true | perf report -i- -s addr [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.000 MB - ] # Samples: 12 of event 'cycles:u' # Event count (approx.): 252512 # # Overhead Address # ........ .................. 42.96% 0x7f96f08443d7 29.55% 0x7f96f0859b50 14.76% 0x7f96f0852e02 8.30% 0x7f96f0855028 4.43% 0xffffffff8de01087 perf annotate: Toggle full address <-> offset display - Add 'f' hotkey to the 'perf annotate' TUI interface when in 'disassembler output' mode ('o' hotkey) to toggle showing full virtual address or just the offset. - Cache DSO build-ids when synthesizing PERF_RECORD_MMAP records for pre-existing threads, at the start of a 'perf record' session, speeding up that record startup phase. - Add a command line option to specify build ids in 'perf inject'. - Update JSON event files for the Intel alderlake, broadwell, broadwellde, broadwellx, cascadelakex, haswell, haswellx, icelake, icelakex, ivybridge, ivytown, jaketown, sandybridge, sapphirerapids, skylake, skylakex, and tigerlake processors. - Update vendor JSON event files for the ARM Neoverse V1 and E1 platforms. - Add a 'perf test' entry for 'perf mem' where a struct has false sharing and this gets detected in the 'perf mem' output, tested with Intel, AMD and ARM64 systems. - Add a 'perf test' entry to test the resolution of java symbols, where an output like this is expected: 8.18% jshell jitted-50116-29.so [.] Interpreter 0.75% Thread-1 jitted-83602-1670.so [.] jdk.internal.jimage.BasicImageReader.getString(int) - Add tests for the ARM64 CoreSight hardware tracing feature, with specially crafted pureloop, memcpy, thread loop and unroll tread that then gets traced and the output compared with expected output. Documentation explaining it is also included. - Add per thread Intel PT 'perf test' entry to check that PERF_RECORD_TEXT_POKE events are recorded per CPU, resulting in a mixture of per thread and per CPU events and mmaps, verify that this gets all recorded correctly. - Introduce pthread mutex wrappers to allow for building with clang's -Wthread-safety, i.e. using the "guarded_by" "pt_guarded_by" "lockable", "exclusive_lock_function", "exclusive_trylock_function", "exclusive_locks_required", and "no_thread_safety_analysis" compiler function attributes. - Fix empty version number when building outside of a git repo. - Improve feature detection display when multiple versions of a feature are present, such as for binutils libbfd, that has a mix of possible ways to detect according to the Linux distribution. Previously in some cases we had: Auto-detecting system features <SNIP> ... libbfd: [ on ] ... libbfd-liberty: [ on ] ... libbfd-liberty-z: [ on ] <SNIP> Now for this case we show just the main feature: Auto-detecting system features <SNIP> ... libbfd: [ on ] <SNIP> - Remove some unused structs, variables, macros, function prototypes and includes from various places. * tag 'perf-tools-for-v6.1-1-2022-10-07' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (169 commits) perf script: Add missing fields in usage hint perf mem: Print "LFB/MAB" for PERF_MEM_LVLNUM_LFB perf mem/c2c: Avoid printing empty lines for unsupported events perf mem/c2c: Add load store event mappings for AMD perf mem/c2c: Set PERF_SAMPLE_WEIGHT for LOAD_STORE events perf mem: Add support for printing PERF_MEM_LVLNUM_{CXL|IO} perf amd ibs: Sync arch/x86/include/asm/amd-ibs.h header with the kernel tools headers UAPI: Sync include/uapi/linux/perf_event.h header with the kernel perf stat: Fix cpu check to use id.cpu.cpu in aggr_printout() perf test coresight: Add relevant documentation about ARM64 CoreSight testing perf test: Add git ignore for tmp and output files of ARM CoreSight tests perf test coresight: Add unroll thread test shell script perf test coresight: Add unroll thread test tool perf test coresight: Add thread loop test shell scripts perf test coresight: Add thread loop test tool perf test coresight: Add memcpy thread test shell script perf test coresight: Add memcpy thread test tool perf test: Add git ignore for perf data generated by the ARM CoreSight tests perf test: Add arm64 asm pureloop test shell script perf test: Add asm pureloop test tool ...
2022-10-10Merge tag 'trace-v6.1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing updates from Steven Rostedt: "Major changes: - Changed location of tracing repo from personal git repo to: git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace.git - Added Masami Hiramatsu as co-maintainer - Updated MAINTAINERS file to separate out FTRACE as it is more than just TRACING. Minor changes: - Added Mark Rutland as FTRACE reviewer - Updated user_events to make it on its way to remove the BROKEN tag. The changes should now be acceptable but will run it through a cycle and hopefully we can remove the BROKEN tag next release. - Added filtering to eprobes - Added a delta time to the benchmark trace event - Have the histogram and filter callbacks called via a switch statement instead of indirect functions. This speeds it up to avoid retpolines. - Add a way to wake up ring buffer waiters waiting for the ring buffer to fill up to its watermark. - New ioctl() on the trace_pipe_raw file to wake up ring buffer waiters. - Wake up waiters when the ring buffer is disabled. A reader may block when the ring buffer is disabled, but if it was blocked when the ring buffer is disabled it should then wake up. Fixes: - Allow splice to read partially read ring buffer pages. This fixes splice never moving forward. - Fix inverted compare that made the "shortest" ring buffer wait queue actually the longest. - Fix a race in the ring buffer between resetting a page when a writer goes to another page, and the reader. - Fix ftrace accounting bug when function hooks are added at boot up before the weak functions are set to "disabled". - Fix bug that freed a user allocated snapshot buffer when enabling a tracer. - Fix possible recursive locks in osnoise tracer - Fix recursive locking direct functions - Other minor clean ups and fixes" * tag 'trace-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (44 commits) ftrace: Create separate entry in MAINTAINERS for function hooks tracing: Update MAINTAINERS to reflect new tracing git repo tracing: Do not free snapshot if tracer is on cmdline ftrace: Still disable enabled records marked as disabled tracing/user_events: Move pages/locks into groups to prepare for namespaces tracing: Add Masami Hiramatsu as co-maintainer tracing: Remove unused variable 'dups' MAINTAINERS: add myself as a tracing reviewer ring-buffer: Fix race between reset page and reading page tracing/user_events: Update ABI documentation to align to bits vs bytes tracing/user_events: Use bits vs bytes for enabled status page data tracing/user_events: Use refcount instead of atomic for ref tracking tracing/user_events: Ensure user provided strings are safely formatted tracing/user_events: Use WRITE instead of READ for io vector import tracing/user_events: Use NULL for strstr checks tracing: Fix spelling mistake "preapre" -> "prepare" tracing: Wake up waiters when tracing is disabled tracing: Add ioctl() to force ring buffer waiters to wake up tracing: Wake up ring buffer waiters on closing of the file ring-buffer: Add ring_buffer_wake_waiters() ...
2022-10-10docs: ftrace: Correct access modeLeo Yan
The documentation gives an example for opening trace marker with write-only mode, but the flag WR_ONLY is not defined by glibc. Use O_WRONLY to replace it. Signed-off-by: Leo Yan <leo.yan@linaro.org> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20221008083250.3160-1-leo.yan@linaro.org Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-10-08Merge tag 'char-misc-6.1-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc and other driver updates from Greg KH: "Here is the large set of char/misc and other small driver subsystem changes for 6.1-rc1. Loads of different things in here: - IIO driver updates, additions, and changes. Probably the largest part of the diffstat - habanalabs driver update with support for new hardware and features, the second largest part of the diff. - fpga subsystem driver updates and additions - mhi subsystem updates - Coresight driver updates - gnss subsystem updates - extcon driver updates - icc subsystem updates - fsi subsystem updates - nvmem subsystem and driver updates - misc driver updates - speakup driver additions for new features - lots of tiny driver updates and cleanups All of these have been in the linux-next tree for a while with no reported issues" * tag 'char-misc-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (411 commits) w1: Split memcpy() of struct cn_msg flexible array spmi: pmic-arb: increase SPMI transaction timeout delay spmi: pmic-arb: block access for invalid PMIC arbiter v5 SPMI writes spmi: pmic-arb: correct duplicate APID to PPID mapping logic spmi: pmic-arb: add support to dispatch interrupt based on IRQ status spmi: pmic-arb: check apid against limits before calling irq handler spmi: pmic-arb: do not ack and clear peripheral interrupts in cleanup_irq spmi: pmic-arb: handle spurious interrupt spmi: pmic-arb: add a print in cleanup_irq drivers: spmi: Directly use ida_alloc()/free() MAINTAINERS: add TI ECAP driver info counter: ti-ecap-capture: capture driver support for ECAP Documentation: ABI: sysfs-bus-counter: add frequency & num_overflows items dt-bindings: counter: add ti,am62-ecap-capture.yaml counter: Introduce the COUNTER_COMP_ARRAY component type counter: Consolidate Counter extension sysfs attribute creation counter: Introduce the Count capture component counter: 104-quad-8: Add Signal polarity component counter: Introduce the Signal polarity component counter: interrupt-cnt: Implement watch_validate callback ...
2022-10-06perf test coresight: Add relevant documentation about ARM64 CoreSight testingCarsten Haitzler
Add/improve documentation helping people get started with CoreSight and perf as well as describe the testing and how it works. Reviewed-by: James Clark <james.clark@arm.com> Signed-off-by: Carsten Haitzler <carsten.haitzler@arm.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Mike Leach <mike.leach@linaro.org> Cc: Suzuki Poulouse <suzuki.poulose@arm.com> Cc: coresight@lists.linaro.org Cc: linux-doc@vger.kernel.org Link: https://lore.kernel.org/r/20220909152803.2317006-14-carsten.haitzler@foss.arm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-09-29docs, kprobes: Fix the wrong location of KprobesTiezhu Yang
After commit 22471e1313f2 ("kconfig: use a menu in arch/Kconfig to reduce clutter"), the location of Kprobes is under "General architecture-dependent options" rather than "General setup". Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Fixes: 22471e1313f2 ("kconfig: use a menu in arch/Kconfig to reduce clutter") Link: https://lore.kernel.org/r/1663322106-12178-1-git-send-email-yangtiezhu@loongson.cn Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-09-29tracing/user_events: Update ABI documentation to align to bits vs bytesBeau Belgrave
Update the documentation to reflect the new ABI requirements and how to use the byte index with the mask properly to check event status. Link: https://lkml.kernel.org/r/20220728233309.1896-7-beaub@linux.microsoft.com Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-09-27Delete duplicate words from kernel docsAkhil Raj
I have deleted duplicate words like to, guest, trace, when, we Signed-off-by: Akhil Raj <lf32.dev@gmail.com> Link: https://lore.kernel.org/r/20220829065239.4531-1-lf32.dev@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-09-08docs: trace: Add HiSilicon PTT device driver documentationYicong Yang
Document the introduction and usage of HiSilicon PTT device driver as well as the sysfs attributes description provided by the driver. Signed-off-by: Yicong Yang <yangyicong@hisilicon.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> [Fixed month and kernel version] Link: https://lore.kernel.org/r/20220816114414.4092-5-yangyicong@huawei.com Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
2022-08-26coresight: etm4x: docs: Add documentation for 'ts_source' sysfs interfaceGerman Gomez
Sync sysfs documentation pages to include the new ts_source (timestamp source) interface. Signed-off-by: German Gomez <german.gomez@arm.com> Signed-off-by: James Clark <james.clark@arm.com> Link: https://lore.kernel.org/r/20220823160650.455823-3-james.clark@arm.com Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
2022-08-22coresight: docs: Fix a broken referenceChristophe JAILLET
Since the commit in Fixes: tag, "coresight-cpu-debug.txt" has been turned into "arm,coresight-cpu-debug.yaml". Update the doc accordingly to avoid a 'make htmldocs' warning Fixes: 66d052047ca8 ("dt-bindings: arm: Convert CoreSight CPU debug to DT schema") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Reviewed-by: James Clark <james.clark@arm.com> Link: https://lore.kernel.org/r/c7f864854e9e03916017712017ff59132c51c338.1659251193.git.christophe.jaillet@wanadoo.fr Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
2022-08-05Merge tag 'trace-v6.0' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: - Runtime verification infrastructure This is the biggest change here. It introduces the runtime verification that is necessary for running Linux on safety critical systems. It allows for deterministic automata models to be inserted into the kernel that will attach to tracepoints, where the information on these tracepoints will move the model from state to state. If a state is encountered that does not belong to the model, it will then activate a given reactor, that could just inform the user or even panic the kernel (for which safety critical systems will detect and can recover from). - Two monitor models are also added: Wakeup In Preemptive (WIP - not to be confused with "work in progress"), and Wakeup While Not Running (WWNR). - Added __vstring() helper to the TRACE_EVENT() macro to replace several vsnprintf() usages that were all doing it wrong. - eprobes now can have their event autogenerated when the event name is left off. - The rest is various cleanups and fixes. * tag 'trace-v6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (50 commits) rv: Unlock on error path in rv_unregister_reactor() tracing: Use alignof__(struct {type b;}) instead of offsetof() tracing/eprobe: Show syntax error logs in error_log file scripts/tracing: Fix typo 'the the' in comment tracepoints: It is CONFIG_TRACEPOINTS not CONFIG_TRACEPOINT tracing: Use free_trace_buffer() in allocate_trace_buffers() tracing: Use a struct alignof to determine trace event field alignment rv/reactor: Add the panic reactor rv/reactor: Add the printk reactor rv/monitor: Add the wwnr monitor rv/monitor: Add the wip monitor rv/monitor: Add the wip monitor skeleton created by dot2k Documentation/rv: Add deterministic automata instrumentation documentation Documentation/rv: Add deterministic automata monitor synthesis documentation tools/rv: Add dot2k Documentation/rv: Add deterministic automaton documentation tools/rv: Add dot2c Documentation/rv: Add a basic documentation rv/include: Add instrumentation helper functions rv/include: Add deterministic automata monitor definition via C macros ...
2022-07-30rv/monitor: Add the wwnr monitorDaniel Bristot de Oliveira
Per task wakeup while not running (wwnr) monitor. This model is broken, the reason is that a task can be running in the processor without being set as RUNNABLE. Think about a task about to sleep: 1: set_current_state(TASK_UNINTERRUPTIBLE); 2: schedule(); And then imagine an IRQ happening in between the lines one and two, waking the task up. BOOM, the wakeup will happen while the task is running. Q: Why do we need this model, so? A: To test the reactors. Link: https://lkml.kernel.org/r/473c0fc39967250fdebcff8b620311c11dccad30.1659052063.git.bristot@kernel.org Cc: Wim Van Sebroeck <wim@linux-watchdog.org> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marco Elver <elver@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Gabriele Paoloni <gpaoloni@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Tao Zhou <tao.zhou@linux.dev> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-30rv/monitor: Add the wip monitorDaniel Bristot de Oliveira
The wakeup in preemptive (wip) monitor verifies if the wakeup events always take place with preemption disabled: | | v #==================# H preemptive H <+ #==================# | | | | preempt_disable | preempt_enable v | sched_waking +------------------+ | +--------------- | | | | | non_preemptive | | +--------------> | | -+ +------------------+ The wakeup event always takes place with preemption disabled because of the scheduler synchronization. However, because the preempt_count and its trace event are not atomic with regard to interrupts, some inconsistencies might happen. The documentation illustrates one of these cases. Link: https://lkml.kernel.org/r/c98ca678df81115fddc04921b3c79720c836b18f.1659052063.git.bristot@kernel.org Cc: Wim Van Sebroeck <wim@linux-watchdog.org> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marco Elver <elver@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: "Paul E. McKenney" <paulmck@kernel.org> Cc: Shuah Khan <skhan@linuxfoundation.org> Cc: Gabriele Paoloni <gpaoloni@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Tao Zhou <tao.zhou@linux.dev> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-trace-devel@vger.kernel.org Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>