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2025-11-26function_graph: Enable funcgraph-args and funcgraph-retaddr to work ↵pengdonglin-32/+78
simultaneously Currently, the funcgraph-args and funcgraph-retaddr features are mutually exclusive. This patch resolves this limitation by allowing funcgraph-retaddr to have an args array. To verify the change, use perf to trace vfs_write with both options enabled: Before: # perf ftrace -G vfs_write --graph-opts args,retaddr ...... down_read() { /* <-n_tty_write+0xa3/0x540 */ __cond_resched(); /* <-down_read+0x12/0x160 */ preempt_count_add(); /* <-down_read+0x3b/0x160 */ preempt_count_sub(); /* <-down_read+0x8b/0x160 */ } After: # perf ftrace -G vfs_write --graph-opts args,retaddr ...... down_read(sem=0xffff8880100bea78) { /* <-n_tty_write+0xa3/0x540 */ __cond_resched(); /* <-down_read+0x12/0x160 */ preempt_count_add(val=1); /* <-down_read+0x3b/0x160 */ preempt_count_sub(val=1); /* <-down_read+0x8b/0x160 */ } Cc: Steven Rostedt (Google) <rostedt@goodmis.org> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Xiaoqin Zhang <zhangxiaoqin@xiaomi.com> Link: https://patch.msgid.link/20251125093425.2563849-1-dolinux.peng@gmail.com Signed-off-by: pengdonglin <pengdonglin@xiaomi.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-26tracing: Add boot-time backup of persistent ring bufferMasami Hiramatsu (Google)-6/+58
Currently, the persistent ring buffer instance needs to be read before using it. This means we have to wait for boot up user space and dump the persistent ring buffer. However, in that case we can not start tracing on it from the kernel cmdline. To solve this limitation, this adds an option which allows to create a trace instance as a backup of the persistent ring buffer at boot. If user specifies trace_instance=<BACKUP>=<PERSIST_RB> then the <BACKUP> instance is made as a copy of the <PERSIST_RB> instance. For example, the below kernel cmdline records all syscalls, scheduler and interrupt events on the persistent ring buffer `boot_map` but before starting the tracing, it makes a `backup` instance from the `boot_map`. Thus, the `backup` instance has the previous boot events. 'reserve_mem=12M:4M:trace trace_instance=boot_map@trace,syscalls:*,sched:*,irq:* trace_instance=backup=boot_map' As you can see, this just make a copy of entire reserved area and make a backup instance on it. So you can release (or shrink) the backup instance after use it to save the memory usage. /sys/kernel/tracing/instances # free total used free shared buff/cache available Mem: 1999284 55704 1930520 10132 13060 1914628 Swap: 0 0 0 /sys/kernel/tracing/instances # rmdir backup/ /sys/kernel/tracing/instances # free total used free shared buff/cache available Mem: 1999284 40640 1945584 10132 13060 1929692 Swap: 0 0 0 Note: since there is no reason to make a copy of empty buffer, this backup only accepts a persistent ring buffer as the original instance. Also, since this backup is based on vmalloc(), it does not support user-space mmap(). Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Link: https://patch.msgid.link/176377150002.219692.9425536150438129267.stgit@devnote2 Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-26ftrace: Allow tracing of some of the tracing codeSteven Rostedt-0/+31
There is times when tracing the tracing infrastructure can be useful for debugging the tracing code. Currently all files in the tracing directory are set to "notrace" the functions. Add a new config option FUNCTION_SELF_TRACING that will allow some of the files in the tracing infrastructure to be traced. It requires a config to enable because it will add noise to the function tracer if events and other tracing features are enabled. Tracing functions and events together is quite common, so not tracing the event code should be the default. Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Tom Zanussi <zanussi@kernel.org> Link: https://patch.msgid.link/20251120181514.736f2d5f@gandalf.local.home Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-26tracing: Use strim() in trigger_process_regex() instead of skip_spaces()Steven Rostedt-3/+2
The function trigger_process_regex() is called by a few functions, where only one calls strim() on the buffer passed to it. That leaves the other functions not trimming the end of the buffer passed in and making it a little inconsistent. Remove the strim() from event_trigger_regex_write() and have trigger_process_regex() use strim() instead of skip_spaces(). The buff variable is not passed in as const, so it can be modified. Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tom Zanussi <zanussi@kernel.org> Link: https://patch.msgid.link/20251125214032.323747707@kernel.org Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-26tracing: Add bulk garbage collection of freeing event_trigger_dataSteven Rostedt-3/+54
The event trigger data requires a full tracepoint_synchronize_unregister() call before freeing. That call can take 100s of milliseconds to complete. In order to allow for bulk freeing of the trigger data, it can not call the tracepoint_synchronize_unregister() for every individual trigger data being free. Create a kthread that gets created the first time a trigger data is freed, and have it use the lockless llist to get the list of data to free, run the tracepoint_synchronize_unregister() then free everything in the list. By freeing hundreds of event_trigger_data elements together, it only requires two runs of the synchronization function, and not hundreds of runs. This speeds up the operation by orders of magnitude (milliseconds instead of several seconds). Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tom Zanussi <zanussi@kernel.org> Link: https://patch.msgid.link/20251125214032.151674992@kernel.org Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-26tracing: Remove unneeded event_mutex lock in event_trigger_regex_release()Steven Rostedt-4/+0
In event_trigger_regex_release(), the only code is: mutex_lock(&event_mutex); if (file->f_mode & FMODE_READ) seq_release(inode, file); mutex_unlock(&event_mutex); return 0; There's nothing special about the file->f_mode or the seq_release() that requires any locking. Remove the unnecessary locks. Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tom Zanussi <zanussi@kernel.org> Link: https://patch.msgid.link/20251125214031.975879283@kernel.org Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-26tracing: Merge struct event_trigger_ops into struct event_commandSteven Rostedt-202/+151
Now that there's pretty much a one to one mapping between the struct event_trigger_ops and struct event_command, there's no reason to have two different structures. Merge the function pointers of event_trigger_ops into event_command. There's one exception in trace_events_hist.c for the event_hist_trigger_named_ops. This has special logic for the init and free function pointers for "named histograms". In this case, allocate the cmd_ops of the event_trigger_data and set it to the proper init and free functions, which are used to initialize and free the event_trigger_data respectively. Have the free function and the init function (on failure) free the cmd_ops of the data element. Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Link: https://patch.msgid.link/20251125200932.446322765@kernel.org Reviewed-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-26tracing: Remove get_trigger_ops() and add count_func() from trigger opsSteven Rostedt-235/+116
The struct event_command has a callback function called get_trigger_ops(). This callback returns the "trigger_ops" to use for the trigger. These ops define the trigger function, how to init the trigger, how to print the trigger and how to free it. The only reason there's a callback function to get these ops is because some triggers have two types of operations. One is an "always on" operation, and the other is a "count down" operation. If a user passes in a parameter to say how many times the trigger should execute. For example: echo stacktrace:5 > events/kmem/kmem_cache_alloc/trigger It will trigger the stacktrace for the first 5 times the kmem_cache_alloc event is hit. Instead of having two different trigger_ops since the only difference between them is the tigger itself (the print, init and free functions are all the same), just use a single ops that the event_command points to and add a function field to the trigger_ops to have a count_func. When a trigger is added to an event, if there's a count attached to it and the trigger ops has the count_func field, the data allocated to represent this trigger will have a new flag set called COUNT. Then when the trigger executes, it will check if the COUNT data flag is set, and if so, it will call the ops count_func(). If that returns false, it returns without executing the trigger. This removes the need for duplicate event_trigger_ops structures. Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Link: https://patch.msgid.link/20251125200932.274566147@kernel.org Reviewed-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-26tracing: Show the tracer options in boot-time created instanceMasami Hiramatsu (Google)-3/+6
Since tracer_init_tracefs_work_func() only updates the tracer options for the global_trace, the instances created by the kernel cmdline do not have those options. Fix to update tracer options for those boot-time created instances to show those options. Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Link: https://patch.msgid.link/176354112555.2356172.3989277078358802353.stgit@mhiramat.tok.corp.google.com Fixes: 428add559b69 ("tracing: Have tracer option be instance specific") Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-26ftrace: Avoid redundant initialization in register_ftrace_directMenglong Dong-1/+1
The FTRACE_OPS_FL_INITIALIZED flag is cleared in register_ftrace_direct, which can make it initialized by ftrace_ops_init() even if it is already initialized. It seems that there is no big deal here, but let's still fix it. Link: https://patch.msgid.link/20251110121808.1559240-1-dongml2@chinatelecom.cn Fixes: f64dd4627ec6 ("ftrace: Add multi direct register/unregister interface") Acked-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-26tracing: Remove unused variable in tracing_trace_options_show()Steven Rostedt-3/+0
The flags and opts used in tracing_trace_options_show() now come directly from the trace array "current_trace_flags" and not the current_trace. The variable "trace" was still being assigned to tr->current_trace but never used. This caused a warning in clang. Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Link: https://patch.msgid.link/20251117120637.43ef995d@gandalf.local.home Reported-by: Andy Shevchenko <andriy.shevchenko@intel.com> Tested-by: Andy Shevchenko <andriy.shevchenko@intel.com> Closes: https://lore.kernel.org/all/aRtHWXzYa8ijUIDa@black.igk.intel.com/ Fixes: 428add559b692 ("tracing: Have tracer option be instance specific") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-26fgraph: Make fgraph_no_sleep_time signedSteven Rostedt-2/+2
The variable fgraph_no_sleep_time changed from being a boolean to being a counter. A check is made to make sure that it never goes below zero. But the variable being unsigned makes the check always fail even if it does go below zero. Make the variable a signed int so that checking it going below zero still works. Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Link: https://patch.msgid.link/20251125104751.4c9c7f28@gandalf.local.home Fixes: 5abb6ccb58f0 ("tracing: Have function graph tracer option sleep-time be per instance") Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Closes: https://lore.kernel.org/all/aR1yRQxDmlfLZzoo@stanley.mountain/ Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-25tracing: Fix WARN_ON in tracing_buffers_mmap_close for split VMAsDeepanshu Kartikey-0/+10
When a VMA is split (e.g., by partial munmap or MAP_FIXED), the kernel calls vm_ops->close on each portion. For trace buffer mappings, this results in ring_buffer_unmap() being called multiple times while ring_buffer_map() was only called once. This causes ring_buffer_unmap() to return -ENODEV on subsequent calls because user_mapped is already 0, triggering a WARN_ON. Trace buffer mappings cannot support partial mappings because the ring buffer structure requires the complete buffer including the meta page. Fix this by adding a may_split callback that returns -EINVAL to prevent VMA splits entirely. Cc: stable@vger.kernel.org Fixes: cf9f0f7c4c5bb ("tracing: Allow user-space mapping of the ring-buffer") Link: https://patch.msgid.link/20251119064019.25904-1-kartikey406@gmail.com Closes: https://syzkaller.appspot.com/bug?extid=a72c325b042aae6403c7 Tested-by: syzbot+a72c325b042aae6403c7@syzkaller.appspotmail.com Reported-by: syzbot+a72c325b042aae6403c7@syzkaller.appspotmail.com Signed-off-by: Deepanshu Kartikey <kartikey406@gmail.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-24ftrace: Introduce FTRACE_OPS_FL_JMPMenglong Dong-1/+28
For now, the "nop" will be replaced with a "call" instruction when a function is hooked by the ftrace. However, sometimes the "call" can break the RSB and introduce extra overhead. Therefore, introduce the flag FTRACE_OPS_FL_JMP, which indicate that the ftrace_ops should be called with a "jmp" instead of "call". For now, it is only used by the direct call case. When a direct ftrace_ops is marked with FTRACE_OPS_FL_JMP, the last bit of the ops->direct_call will be set to 1. Therefore, we can tell if we should use "jmp" for the callback in ftrace_call_replace(). Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20251118123639.688444-2-dongml2@chinatelecom.cn Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-11-19tracing: Switch to use %ptSpAndy Shevchenko-3/+3
Use %ptSp instead of open coded variants to print content of struct timespec64 in human readable format. Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://patch.msgid.link/20251113150217.3030010-22-andriy.shevchenko@linux.intel.com Signed-off-by: Petr Mladek <pmladek@suse.com>
2025-11-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf after 6.18-rc5+Alexei Starovoitov-18/+59
Cross-merge BPF and other fixes after downstream PR. Minor conflict in kernel/bpf/helpers.c Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-11-14Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfLinus Torvalds-15/+45
Pull bpf fixes from Alexei Starovoitov: - Fix interaction between livepatch and BPF fexit programs (Song Liu) With Steven and Masami acks. - Fix stack ORC unwind from BPF kprobe_multi (Jiri Olsa) With Steven and Masami acks. - Fix out of bounds access in widen_imprecise_scalars() in the verifier (Eduard Zingerman) - Fix conflicts between MPTCP and BPF sockmap (Jiayuan Chen) - Fix net_sched storage collision with BPF data_meta/data_end (Eric Dumazet) - Add _impl suffix to BPF kfuncs with implicit args to avoid breaking them in bpf-next when KF_IMPLICIT_ARGS is added (Mykyta Yatsenko) * tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: selftests/bpf: Test widen_imprecise_scalars() with different stack depth bpf: account for current allocated stack depth in widen_imprecise_scalars() bpf: Add bpf_prog_run_data_pointers() selftests/bpf: Add mptcp test with sockmap mptcp: Fix proto fallback detection with BPF mptcp: Disallow MPTCP subflows from sockmap selftests/bpf: Add stacktrace ips test for raw_tp selftests/bpf: Add stacktrace ips test for kprobe_multi/kretprobe_multi x86/fgraph,bpf: Fix stack ORC unwind from kprobe_multi return probe Revert "perf/x86: Always store regs->ip in perf_callchain_kernel()" bpf: add _impl suffix for bpf_stream_vprintk() kfunc bpf:add _impl suffix for bpf_task_work_schedule* kfuncs selftests/bpf: Add tests for livepatch + bpf trampoline ftrace: bpf: Fix IPMODIFY + DIRECT in modify_ftrace_direct() ftrace: Fix BPF fexit with livepatch
2025-11-14tracing: Convert function graph set_flags() to use a switch() statementSteven Rostedt-5/+7
Currently the set_flags() of the function graph tracer has a bunch of: if (bit == FLAG1) { [..] } if (bit == FLAG2) { [..] } To clean it up a bit, convert it over to a switch statement. Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Link: https://patch.msgid.link/20251114192319.117123664@kernel.org Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-14tracing: Have function graph tracer option sleep-time be per instanceSteven Rostedt-23/+60
Currently the option to have function graph tracer to ignore time spent when a task is sleeping is global when the interface is per-instance. Changing the value in one instance will affect the results of another instance that is also running the function graph tracer. This can lead to confusing results. Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Link: https://patch.msgid.link/20251114192318.950255167@kernel.org Fixes: c132be2c4fcc1 ("function_graph: Have the instances use their own ftrace_ops for filtering") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-14tracing: Move graph-time out of function graph optionsSteven Rostedt-14/+23
The option "graph-time" affects the function profiler when it is using the function graph infrastructure. It has nothing to do with the function graph tracer itself. The option only affects the global function profiler and does nothing to the function graph tracer. Move it out of the function graph tracer options and make it a global option that is only available at the top level instance. Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Link: https://patch.msgid.link/20251114192318.781711154@kernel.org Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-14tracing: Have function graph tracer option funcgraph-irqs be per instanceSteven Rostedt-10/+31
Currently the option to trace interrupts in the function graph tracer is global when the interface is per-instance. Changing the value in one instance will affect the results of another instance that is also running the function graph tracer. This can lead to confusing results. Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Link: https://patch.msgid.link/20251114192318.613867934@kernel.org Fixes: c132be2c4fcc1 ("function_graph: Have the instances use their own ftrace_ops for filtering") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-13trace/pid_list: optimize pid_list->lock contentionYongliang Gao-9/+22
When the system has many cores and task switching is frequent, setting set_ftrace_pid can cause frequent pid_list->lock contention and high system sys usage. For example, in a 288-core VM environment, we observed 267 CPUs experiencing contention on pid_list->lock, with stack traces showing: #4 [ffffa6226fb4bc70] native_queued_spin_lock_slowpath at ffffffff99cd4b7e #5 [ffffa6226fb4bc90] _raw_spin_lock_irqsave at ffffffff99cd3e36 #6 [ffffa6226fb4bca0] trace_pid_list_is_set at ffffffff99267554 #7 [ffffa6226fb4bcc0] trace_ignore_this_task at ffffffff9925c288 #8 [ffffa6226fb4bcd8] ftrace_filter_pid_sched_switch_probe at ffffffff99246efe #9 [ffffa6226fb4bcf0] __schedule at ffffffff99ccd161 Replaces the existing spinlock with a seqlock to allow concurrent readers, while maintaining write exclusivity. Link: https://patch.msgid.link/20251113000252.1058144-1-leonylgao@gmail.com Reviewed-by: Huang Cun <cunhuang@tencent.com> Signed-off-by: Yongliang Gao <leonylgao@tencent.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-13tracing: Have function graph tracer define options per instanceSteven Rostedt-7/+11
Currently the function graph tracer's options are saved via a global mask when it should be per instance. Use the new infrastructure to define a "default_flags" field in the tracer structure that is used for the top level instance as well as new ones. Currently the global mask causes confusion: # cd /sys/kernel/tracing # mkdir instances/foo # echo function_graph > instances/foo/current_tracer # echo 1 > options/funcgraph-args # echo function_graph > current_tracer # cat trace [..] 2) | _raw_spin_lock_irq(lock=0xffff96b97dea16c0) { 2) 0.422 us | do_raw_spin_lock(lock=0xffff96b97dea16c0); 7) | rcu_sched_clock_irq(user=0) { 2) 1.478 us | } 7) 0.758 us | rcu_is_cpu_rrupt_from_idle(); 2) 0.647 us | enqueue_hrtimer(timer=0xffff96b97dea2058, base=0xffff96b97dea1740, mode=0); # cat instances/foo/options/funcgraph-args 1 # cat instances/foo/trace [..] 4) | __x64_sys_read() { 4) | ksys_read() { 4) 0.755 us | fdget_pos(); 4) | vfs_read() { 4) | rw_verify_area() { 4) | security_file_permission() { 4) | apparmor_file_permission() { 4) | common_file_perm() { 4) | aa_file_perm() { 4) | rcu_read_lock_held() { [..] The above shows that updating the "funcgraph-args" option at the top level instance also updates the "funcgraph-args" option in the instance but because the update is only done by the instance that gets changed (as it should), it's confusing to see that the option is already set in the other instance. Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Link: https://patch.msgid.link/20251111232429.641030027@kernel.org Fixes: c132be2c4fcc1 ("function_graph: Have the instances use their own ftrace_ops for filtering") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-12tracing: Have function tracer define options per instanceSteven Rostedt-5/+5
Currently the function tracer's options are saved via a global mask when it should be per instance. Use the new infrastructure to define a "default_flags" field in the tracer structure that is used for the top level instance as well as new ones. Currently the global mask causes confusion: # cd /sys/kernel/tracing # mkdir instances/foo # echo function > instances/foo/current_tracer # echo 1 > options/func-args # echo function > current_tracer # cat trace [..] <idle>-0 [005] d..3. 1050.656187: rcu_needs_cpu() <-tick_nohz_next_event <idle>-0 [005] d..3. 1050.656188: get_next_timer_interrupt(basej=0x10002dbad, basem=0xf45fd7d300) <-tick_nohz_next_event <idle>-0 [005] d..3. 1050.656189: _raw_spin_lock(lock=0xffff8944bdf5de80) <-__get_next_timer_interrupt <idle>-0 [005] d..4. 1050.656190: do_raw_spin_lock(lock=0xffff8944bdf5de80) <-__get_next_timer_interrupt <idle>-0 [005] d..4. 1050.656191: _raw_spin_lock_nested(lock=0xffff8944bdf5f140, subclass=1) <-__get_next_timer_interrupt # cat instances/foo/options/func-args 1 # cat instances/foo/trace [..] kworker/4:1-88 [004] ...1. 298.127735: next_zone <-refresh_cpu_vm_stats kworker/4:1-88 [004] ...1. 298.127736: first_online_pgdat <-refresh_cpu_vm_stats kworker/4:1-88 [004] ...1. 298.127738: next_online_pgdat <-refresh_cpu_vm_stats kworker/4:1-88 [004] ...1. 298.127739: fold_diff <-refresh_cpu_vm_stats kworker/4:1-88 [004] ...1. 298.127741: round_jiffies_relative <-vmstat_update [..] The above shows that updating the "func-args" option at the top level instance also updates the "func-args" option in the instance but because the update is only done by the instance that gets changed (as it should), it's confusing to see that the option is already set in the other instance. Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Link: https://patch.msgid.link/20251111232429.470883736@kernel.org Fixes: f20a580627f43 ("ftrace: Allow instances to use function tracing") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-12tracing: Have tracer option be instance specificSteven Rostedt-74/+186
Tracers can add specify options to modify them. This logic was added before instances were created and the tracer flags were global variables. After instances were created where a tracer may exist in more than one instance, the flags were not updated from being global into instance specific. This causes confusion with these options. For example, the function tracer has an option to enable function arguments: # cd /sys/kernel/tracing # mkdir instances/foo # echo function > instances/foo/current_tracer # echo 1 > options/func-args # echo function > current_tracer # cat trace [..] <idle>-0 [005] d..3. 1050.656187: rcu_needs_cpu() <-tick_nohz_next_event <idle>-0 [005] d..3. 1050.656188: get_next_timer_interrupt(basej=0x10002dbad, basem=0xf45fd7d300) <-tick_nohz_next_event <idle>-0 [005] d..3. 1050.656189: _raw_spin_lock(lock=0xffff8944bdf5de80) <-__get_next_timer_interrupt <idle>-0 [005] d..4. 1050.656190: do_raw_spin_lock(lock=0xffff8944bdf5de80) <-__get_next_timer_interrupt <idle>-0 [005] d..4. 1050.656191: _raw_spin_lock_nested(lock=0xffff8944bdf5f140, subclass=1) <-__get_next_timer_interrupt # cat instances/foo/options/func-args 1 # cat instances/foo/trace [..] kworker/4:1-88 [004] ...1. 298.127735: next_zone <-refresh_cpu_vm_stats kworker/4:1-88 [004] ...1. 298.127736: first_online_pgdat <-refresh_cpu_vm_stats kworker/4:1-88 [004] ...1. 298.127738: next_online_pgdat <-refresh_cpu_vm_stats kworker/4:1-88 [004] ...1. 298.127739: fold_diff <-refresh_cpu_vm_stats kworker/4:1-88 [004] ...1. 298.127741: round_jiffies_relative <-vmstat_update [..] The above shows that setting "func-args" in the top level instance also set it in the instance "foo", but since the interface of the trace flags are per instance, the update didn't take affect in the "foo" instance. Update the infrastructure to allow tracers to add a "default_flags" field in the tracer structure that can be set instead of "flags" which will make the flags per instance. If a tracer needs to keep the flags global (like blktrace), keeping the "flags" field set will keep the old behavior. This does not update function or the function graph tracers. That will be handled later. Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Link: https://patch.msgid.link/20251111232429.305317942@kernel.org Fixes: f20a580627f43 ("ftrace: Allow instances to use function tracing") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-11tracing: fprobe: use ftrace if CONFIG_DYNAMIC_FTRACE_WITH_ARGSMenglong Dong-10/+22
For now, we will use ftrace for the fprobe if fp->exit_handler not exists and CONFIG_DYNAMIC_FTRACE_WITH_REGS is enabled. However, CONFIG_DYNAMIC_FTRACE_WITH_REGS is not supported by some arch, such as arm. What we need in the fprobe is the function arguments, so we can use ftrace for fprobe if CONFIG_DYNAMIC_FTRACE_WITH_ARGS is enabled. Therefore, use ftrace if CONFIG_DYNAMIC_FTRACE_WITH_REGS or CONFIG_DYNAMIC_FTRACE_WITH_ARGS enabled. Link: https://lore.kernel.org/all/20251103063434.47388-1-dongml2@chinatelecom.cn/ Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2025-11-11tracing: fprobe: optimization for entry only caseMenglong Dong-9/+119
For now, fgraph is used for the fprobe, even if we need trace the entry only. However, the performance of ftrace is better than fgraph, and we can use ftrace_ops for this case. Then performance of kprobe-multi increases from 54M to 69M. Before this commit: $ ./benchs/run_bench_trigger.sh kprobe-multi kprobe-multi : 54.663 ± 0.493M/s After this commit: $ ./benchs/run_bench_trigger.sh kprobe-multi kprobe-multi : 69.447 ± 0.143M/s Mitigation is disable during the bench testing above. Link: https://lore.kernel.org/all/20251015083238.2374294-2-dongml2@chinatelecom.cn/ Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2025-11-11tracing: fprobe: Fix to init fprobe_ip_table earlierMasami Hiramatsu (Google)-1/+1
Since the fprobe_ip_table is used from module unloading in the failure path of load_module(), it must be initialized in the earlier timing than late_initcall(). Unless that, the fprobe_module_callback() will use an uninitialized spinlock of fprobe_ip_table. Initialize fprobe_ip_table in core_initcall which is the same timing as ftrace. Link: https://lore.kernel.org/all/175939434403.3665022.13030530757238556332.stgit@mhiramat.tok.corp.google.com/ Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202509301440.be4b3631-lkp@intel.com Fixes: e5a4cc28a052 ("tracing: fprobe: use rhltable for fprobe_ip_table") Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Menglong Dong <menglong8.dong@gmail.com>
2025-11-11rv: Add explicit lockdep context for reactorsThomas Weißschuh-0/+4
Reactors can be called from any context through tracepoints. When developing reactors care needs to be taken to only call APIs which are safe. As the tracepoints used during testing may not actually be called from restrictive contexts lockdep may not be helpful. Add explicit overrides to help lockdep find invalid code patterns. The usage of LD_WAIT_FREE will trigger lockdep warnings in the panic reactor. These are indeed valid warnings but they are out of scope for RV and will instead be fixed by the printk subsystem. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Acked-by: Nam Cao <namcao@linutronix.de> Link: https://lore.kernel.org/r/20251014-rv-lockdep-v1-3-0b9e51919ea8@linutronix.de Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
2025-11-11rv: Make rv_reacting_on() staticThomas Weißschuh-1/+1
There are no external users left. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Link: https://lore.kernel.org/r/20251014-rv-lockdep-v1-2-0b9e51919ea8@linutronix.de Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
2025-11-11rv: Pass va_list to reactorsThomas Weißschuh-11/+17
The only thing the reactors can do with the passed in varargs is to convert it into a va_list. Do that in a central helper instead. It simplifies the reactors, removes some hairy macro-generated code and introduces a convenient hook point to modify reactor behavior. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Link: https://lore.kernel.org/r/20251014-rv-lockdep-v1-1-0b9e51919ea8@linutronix.de Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
2025-11-10tracing: Report wrong dynamic event commandMasami Hiramatsu (Google)-2/+9
Report wrong dynamic event type in the command via error_log. ----- # echo "z hoge" > /sys/kernel/tracing/dynamic_events sh: write error: Invalid argument # cat /sys/kernel/tracing/error_log [ 22.977022] dynevent: error: No matching dynamic event type Command: z hoge ^ ----- Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Link: https://patch.msgid.link/176278970056.343441.10528135217342926645.stgit@devnote2 Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-10tracing: Use switch statement instead of ifs in set_tracer_flag()Steven Rostedt-15/+23
The "mask" passed in to set_trace_flag() has a single bit set. The function then checks if the mask is equal to one of the option masks and performs the appropriate function associated to that option. Instead of having a bunch of "if ()" statement, use a "switch ()" statement instead to make it cleaner and a bit more optimal. No function changes. Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Link: https://patch.msgid.link/20251106003501.890298562@kernel.org Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-10tracing: Exit out immediately after update_marker_trace()Steven Rostedt-1/+4
The call to update_marker_trace() in set_tracer_flag() performs the update to the tr->trace_flags. There's no reason to perform it again after it is called. Return immediately instead. Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Link: https://patch.msgid.link/20251106003501.726406870@kernel.org Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-10tracing: Have add_tracer_options() error pass up to callersSteven Rostedt-21/+34
The function add_tracer_options() can fail, but currently it is ignored. Pass the status of add_tracer_options() up to adding a new tracer as well as when an instance is created. Have the instance creation fail if the add_tracer_options() fail. Only print a warning for the top level instance, like it does with other failures. Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Link: https://patch.msgid.link/20251105161935.375299297@kernel.org Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-10tracing: Remove dummy options and flagsSteven Rostedt-32/+16
When a tracer does not define their own flags, dummy options and flags are used so that the values are always valid. There's not that many locations that reference these values so having dummy versions just complicates the code. Remove the dummy values and just check for NULL when appropriate. Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Link: https://patch.msgid.link/20251105161935.206093132@kernel.org Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-10tracing: Hide __NR_utimensat and _NR_mq_timedsend when not definedSteven Rostedt-0/+4
Some architectures (riscv-32) do not define __NR_utimensat and _NR_mq_timedsend, and fails to build when they are used. Hide them in "ifdef"s. Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Link: https://patch.msgid.link/20251104205310.00a1db9a@batman.local.home Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202511031239.ZigDcWzY-lkp@intel.com/ Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-07Merge tag 'trace-v6.18-rc4' of ↵Linus Torvalds-2/+8
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Check for reader catching up in ring_buffer_map_get_reader() If the reader catches up to the writer in the memory mapped ring buffer then calling rb_get_reader_page() will return NULL as there's no pages left. But this isn't checked for before calling rb_get_reader_page() and the return of NULL causes a warning. If it is detected that the reader caught up to the writer, then simply exit the routine - Fix memory leak in histogram create_field_var() The couple of the error paths in create_field_var() did not properly clean up what was allocated. Make sure everything is freed properly on error - Fix help message of tools latency_collector The help message incorrectly stated that "-t" was the same as "--threads" whereas "--threads" is actually represented by "-e" * tag 'trace-v6.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing/tools: Fix incorrcet short option in usage text for --threads tracing: Fix memory leaks in create_field_var() ring-buffer: Do not warn in ring_buffer_map_get_reader() when reader catches up
2025-11-06tracing: Fix memory leaks in create_field_var()Zilin Guan-2/+4
The function create_field_var() allocates memory for 'val' through create_hist_field() inside parse_atom(), and for 'var' through create_var(), which in turn allocates var->type and var->var.name internally. Simply calling kfree() to release these structures will result in memory leaks. Use destroy_hist_field() to properly free 'val', and explicitly release the memory of var->type and var->var.name before freeing 'var' itself. Link: https://patch.msgid.link/20251106120132.3639920-1-zilin@seu.edu.cn Fixes: 02205a6752f22 ("tracing: Add support for 'field variables'") Signed-off-by: Zilin Guan <zilin@seu.edu.cn> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-06ring-buffer: Do not warn in ring_buffer_map_get_reader() when reader catches upSteven Rostedt-0/+4
The function ring_buffer_map_get_reader() is a bit more strict than the other get reader functions, and except for certain situations the rb_get_reader_page() should not return NULL. If it does, it triggers a warning. This warning was triggering but after looking at why, it was because another acceptable situation was happening and it wasn't checked for. If the reader catches up to the writer and there's still data to be read on the reader page, then the rb_get_reader_page() will return NULL as there's no new page to get. In this situation, the reader page should not be updated and no warning should trigger. Cc: stable@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Vincent Donnefort <vdonnefort@google.com> Reported-by: syzbot+92a3745cea5ec6360309@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/690babec.050a0220.baf87.0064.GAE@google.com/ Link: https://lore.kernel.org/20251016132848.1b11bb37@gandalf.local.home Fixes: 117c39200d9d7 ("ring-buffer: Introducing ring-buffer mapping functions") Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-07tracing: tprobe-events: Fix to put tracepoint_user when disable the tprobeMasami Hiramatsu (Google)-0/+4
__unregister_trace_fprobe() checks tf->tuser to put it when removing tprobe. However, disable_trace_fprobe() does not use it and only calls unregister_fprobe(). Thus it forgets to disable tracepoint_user. If the trace_fprobe has tuser, put it for unregistering the tracepoint callbacks when disabling tprobe correctly. Link: https://lore.kernel.org/all/176244794466.155515.3971904050506100243.stgit@devnote2/ Fixes: 2867495dea86 ("tracing: tprobe-events: Register tracepoint when enable tprobe event") Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Tested-by: Beau Belgrave <beaub@linux.microsoft.com> Reviewed-by: Beau Belgrave <beaub@linux.microsoft.com>
2025-11-07tracing: tprobe-events: Fix to register tracepoint correctlyMasami Hiramatsu (Google)-1/+2
Since __tracepoint_user_init() calls tracepoint_user_register() without initializing tuser->tpoint with given tracpoint, it does not register tracepoint stub function as callback correctly, and tprobe does not work. Initializing tuser->tpoint correctly before tracepoint_user_register() so that it sets up tracepoint callback. I confirmed below example works fine again. echo "t sched_switch preempt prev_pid=prev->pid next_pid=next->pid" > /sys/kernel/tracing/dynamic_events echo 1 > /sys/kernel/tracing/events/tracepoints/sched_switch/enable cat /sys/kernel/tracing/trace_pipe Link: https://lore.kernel.org/all/176244793514.155515.6466348656998627773.stgit@devnote2/ Fixes: 2867495dea86 ("tracing: tprobe-events: Register tracepoint when enable tprobe event") Reported-by: Beau Belgrave <beaub@linux.microsoft.com> Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Tested-by: Beau Belgrave <beaub@linux.microsoft.com> Reviewed-by: Beau Belgrave <beaub@linux.microsoft.com>
2025-11-05trace: use override credential guardChristian Brauner-12/+5
Use override credential guards for scoped credential override with automatic restoration on scope exit. Link: https://patch.msgid.link/20251103-work-creds-guards-prepare_creds-v1-12-b447b82f2c9b@kernel.org Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-05trace: use prepare credential guardChristian Brauner-4/+1
Use the prepare credential guard for allocating a new set of credentials. Link: https://patch.msgid.link/20251103-work-creds-guards-prepare_creds-v1-11-b447b82f2c9b@kernel.org Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-04Merge branch 'topic/func-profiler-offset' of ↵Steven Rostedt-154/+197
git://git.kernel.org/pub/scm/linux/kernel/git/mhiramat/linux into trace/trace/core Updates to the function profiler adds new options to tracefs. The options are currently defined by an enum as flags. The added options brings the number of options over 32, which means they can no longer be held in a 32 bit enum. The TRACE_ITER_* flags are converted to a macro TRACE_ITER(*) to allow the creation of options to still be done by macros. This change is intrusive, as it affects all TRACE_ITER* options throughout the trace code. Merge the branch that added these options and converted the TRACE_ITER_* enum into a TRACE_ITER(*) macro, to allow the topic branches to still be developed without conflict. Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-04tracing: Add an option to show symbols in _text+offset for function profilerMasami Hiramatsu (Google)-4/+38
Function profiler shows the hit count of each function using its symbol name. However, there are some same-name local symbols, which we can not distinguish. To solve this issue, this introduces an option to show the symbols in "_text+OFFSET" format. This can avoid exposing the random shift of KASLR. The functions in modules are shown as "MODNAME+OFFSET" where the offset is from ".text". E.g. for the kernel text symbols, specify vmlinux and the output to addr2line, you can find the actual function and source info; $ addr2line -fie vmlinux _text+3078208 __balance_callbacks kernel/sched/core.c:5064 for modules, specify the module file and .text+OFFSET; $ addr2line -fie samples/trace_events/trace-events-sample.ko .text+8224 do_simple_thread_func samples/trace_events/trace-events-sample.c:23 Link: https://lore.kernel.org/all/176187878064.994619.8878296550240416558.stgit@devnote2/ Suggested-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2025-11-04tracing: Allow tracer to add more than 32 optionsMasami Hiramatsu (Google)-150/+159
Since enum trace_iterator_flags is 32bit, the max number of the option flags is limited to 32 and it is fully used now. To add a new option, we need to expand it. So replace the TRACE_ITER_##flag with TRACE_ITER(flag) macro which is 64bit bitmask. Link: https://lore.kernel.org/all/176187877103.994619.166076000668757232.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2025-11-03ftrace: bpf: Fix IPMODIFY + DIRECT in modify_ftrace_direct()Song Liu-9/+31
ftrace_hash_ipmodify_enable() checks IPMODIFY and DIRECT ftrace_ops on the same kernel function. When needed, ftrace_hash_ipmodify_enable() calls ops->ops_func() to prepare the direct ftrace (BPF trampoline) to share the same function as the IPMODIFY ftrace (livepatch). ftrace_hash_ipmodify_enable() is called in register_ftrace_direct() path, but not called in modify_ftrace_direct() path. As a result, the following operations will break livepatch: 1. Load livepatch to a kernel function; 2. Attach fentry program to the kernel function; 3. Attach fexit program to the kernel function. After 3, the kernel function being used will not be the livepatched version, but the original version. Fix this by adding __ftrace_hash_update_ipmodify() to __modify_ftrace_direct() and adjust some logic around the call. Signed-off-by: Song Liu <song@kernel.org> Reviewed-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20251027175023.1521602-3-song@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-03ftrace: Fix BPF fexit with livepatchSong Liu-6/+14
When livepatch is attached to the same function as bpf trampoline with a fexit program, bpf trampoline code calls register_ftrace_direct() twice. The first time will fail with -EAGAIN, and the second time it will succeed. This requires register_ftrace_direct() to unregister the address on the first attempt. Otherwise, the bpf trampoline cannot attach. Here is an easy way to reproduce this issue: insmod samples/livepatch/livepatch-sample.ko bpftrace -e 'fexit:cmdline_proc_show {}' ERROR: Unable to attach probe: fexit:vmlinux:cmdline_proc_show... Fix this by cleaning up the hash when register_ftrace_function_nolock hits errors. Also, move the code that resets ops->func and ops->trampoline to the error path of register_ftrace_direct(); and add a helper function reset_direct() in register_ftrace_direct() and unregister_ftrace_direct(). Fixes: d05cb470663a ("ftrace: Fix modification of direct_function hash while in use") Cc: stable@vger.kernel.org # v6.6+ Reported-by: Andrey Grodzovsky <andrey.grodzovsky@crowdstrike.com> Closes: https://lore.kernel.org/live-patching/c5058315a39d4615b333e485893345be@crowdstrike.com/ Cc: Steven Rostedt (Google) <rostedt@goodmis.org> Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-and-tested-by: Andrey Grodzovsky <andrey.grodzovsky@crowdstrike.com> Signed-off-by: Song Liu <song@kernel.org> Reviewed-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20251027175023.1521602-2-song@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2025-11-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf after 6.18-rc4Alexei Starovoitov-6/+7
Cross-merge BPF and other fixes after downstream PR. No conflicts. Signed-off-by: Alexei Starovoitov <ast@kernel.org>