summaryrefslogtreecommitdiff
path: root/kernel/trace/trace_uprobe.c
AgeCommit message (Collapse)Author
2019-03-15Merge tag 'trace-v5.1-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes and cleanups from Steven Rostedt: "This contains a series of last minute clean ups, small fixes and error checks" * tag 'trace-v5.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing/probe: Verify alloc_trace_*probe() result tracing/probe: Check event/group naming rule at parsing tracing/probe: Check the size of argument name and body tracing/probe: Check event name length correctly tracing/probe: Check maxactive error cases tracing: kdb: Fix ftdump to not sleep trace/probes: Remove kernel doc style from non kernel doc comment tracing/probes: Make reserved_field_names static
2019-03-14tracing/probe: Verify alloc_trace_*probe() resultMasami Hiramatsu
Since alloc_trace_*probe() returns -EINVAL only if !event && !group, it should not happen in trace_*probe_create(). If we catch that case there is a bug. So use WARN_ON_ONCE() instead of pr_info(). Link: http://lkml.kernel.org/r/155253785078.14922.16902223633734601469.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-14tracing/probe: Check event/group naming rule at parsingMasami Hiramatsu
Check event and group naming rule at parsing it instead of allocating probes. Link: http://lkml.kernel.org/r/155253784064.14922.2336893061156236237.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-01-17tracing/uprobes: Fix output for multiple string argumentsAndreas Ziegler
When printing multiple uprobe arguments as strings the output for the earlier arguments would also include all later string arguments. This is best explained in an example: Consider adding a uprobe to a function receiving two strings as parameters which is at offset 0xa0 in strlib.so and we want to print both parameters when the uprobe is hit (on x86_64): $ echo 'p:func /lib/strlib.so:0xa0 +0(%di):string +0(%si):string' > \ /sys/kernel/debug/tracing/uprobe_events When the function is called as func("foo", "bar") and we hit the probe, the trace file shows a line like the following: [...] func: (0x7f7e683706a0) arg1="foobar" arg2="bar" Note the extra "bar" printed as part of arg1. This behaviour stacks up for additional string arguments. The strings are stored in a dynamically growing part of the uprobe buffer by fetch_store_string() after copying them from userspace via strncpy_from_user(). The return value of strncpy_from_user() is then directly used as the required size for the string. However, this does not take the terminating null byte into account as the documentation for strncpy_from_user() cleary states that it "[...] returns the length of the string (not including the trailing NUL)" even though the null byte will be copied to the destination. Therefore, subsequent calls to fetch_store_string() will overwrite the terminating null byte of the most recently fetched string with the first character of the current string, leading to the "accumulation" of strings in earlier arguments in the output. Fix this by incrementing the return value of strncpy_from_user() by one if we did not hit the maximum buffer size. Link: http://lkml.kernel.org/r/20190116141629.5752-1-andreas.ziegler@fau.de Cc: Ingo Molnar <mingo@redhat.com> Cc: stable@vger.kernel.org Fixes: 5baaa59ef09e ("tracing/probes: Implement 'memory' fetch method for uprobes") Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Andreas Ziegler <andreas.ziegler@fau.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-01-17tracing: uprobes: Fix typo in pr_fmt stringAndreas Ziegler
The subsystem-specific message prefix for uprobes was also "trace_kprobe: " instead of "trace_uprobe: " as described in the original commit message. Link: http://lkml.kernel.org/r/20190117133023.19292-1-andreas.ziegler@fau.de Cc: Ingo Molnar <mingo@redhat.com> Cc: stable@vger.kernel.org Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Fixes: 7257634135c24 ("tracing/probe: Show subsystem name in messages") Signed-off-by: Andreas Ziegler <andreas.ziegler@fau.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-10tracing: Consolidate trace_add/remove_event_call back to the nolock functionsSteven Rostedt (VMware)
The trace_add/remove_event_call_nolock() functions were added to allow the tace_add/remove_event_call() code be called when the event_mutex lock was already taken. Now that all callers are done within the event_mutex, there's no reason to have two different interfaces. Remove the current wrapper trace_add/remove_event_call()s and rename the _nolock versions back to the original names. Link: http://lkml.kernel.org/r/154140866955.17322.2081425494660638846.stgit@devbox Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08tracing/uprobes: Use dyn_event framework for uprobe eventsMasami Hiramatsu
Use dyn_event framework for uprobe events. This shows uprobe events on "dynamic_events" file. User can also define new uprobe events via dynamic_events. Link: http://lkml.kernel.org/r/154140858481.17322.9091293846515154065.stgit@devbox Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com> Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08tracing: Integrate similar probe argument parsersMasami Hiramatsu
Integrate similar argument parsers for kprobes and uprobes events into traceprobe_parse_probe_arg(). Link: http://lkml.kernel.org/r/154140850016.17322.9836787731210512176.stgit@devbox Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com> Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08tracing/uprobes: Add busy check when cleanup all uprobesMasami Hiramatsu
Add a busy check loop in cleanup_all_probes() before trying to remove all events in uprobe_events, the same way that kprobe_events does. Without this change, writing null to uprobe_events will try to remove events but if one of them is enabled, it will stop there leaving some events cleared and others not clceared. With this change, writing null to uprobe_events makes sure all events are not enabled before removing events. So, it clears all events, or returns an error (-EBUSY) with keeping all events. Link: http://lkml.kernel.org/r/154140841557.17322.12653952888762532401.stgit@devbox Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com> Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing/uprobes: Fix to return -EFAULT if copy_from_user failedMasami Hiramatsu
Fix probe_mem_read() to return -EFAULT if copy_from_user() failed. The copy_from_user() returns remaining bytes when it failed, but probe_mem_read() caller expects it returns error code like as probe_kernel_read(). Link: http://lkml.kernel.org/r/153547306719.26502.8353484532699160223.stgit@devbox Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing: probeevent: Add $argN for accessing function argsMasami Hiramatsu
Add $argN special fetch variable for accessing function arguments. This allows user to trace the Nth argument easily at the function entry. Note that this returns most probably assignment of registers and stacks. In some case, it may not work well. If you need to access correct registers or stacks you should use perf-probe. Link: http://lkml.kernel.org/r/152465888632.26224.3412465701570253696.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing: probeevent: Unify fetch_insn processing common partMasami Hiramatsu
Unify the fetch_insn bottom process (from stage 2: dereference indirect data) from kprobe and uprobe events, since those are mostly same. Link: http://lkml.kernel.org/r/152465879965.26224.8547240824606804815.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing: probeevent: Append traceprobe_ for exported functionMasami Hiramatsu
Append traceprobe_ for exported function set_print_fmt() as same as other functions. Link: http://lkml.kernel.org/r/152465877071.26224.11143125027282999726.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing: probeevent: Return consumed bytes of dynamic areaMasami Hiramatsu
Cleanup string fetching routine so that returns the consumed bytes of dynamic area and store the string information as data_loc format instead of data_rloc. This simplifies the fetcharg loop. Link: http://lkml.kernel.org/r/152465874163.26224.12125143907501289031.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing: probeevent: Unify fetch type tablesMasami Hiramatsu
Unify {k,u}probe_fetch_type_table to probe_fetch_type_table because the main difference of those type tables (fetcharg methods) are gone. Now we can consolidate it. Link: http://lkml.kernel.org/r/152465871274.26224.13999436317830479698.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing: probeevent: Introduce new argument fetching codeMasami Hiramatsu
Replace {k,u}probe event argument fetching framework with switch-case based. Currently that is implemented with structures, macros and chain of function-pointers, which is more complicated than necessary and may get a performance penalty by retpoline. This simplify that with an array of "fetch_insn" (opcode and oprands), and make process_fetch_insn() just interprets it. No function pointers are used. Link: http://lkml.kernel.org/r/152465868340.26224.2551120475197839464.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing: probeevent: Cleanup argument field definitionMasami Hiramatsu
Cleanup event argument definition code in one place for maintenancability. Link: http://lkml.kernel.org/r/152465862529.26224.9068605421476018902.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10tracing: probeevent: Cleanup print argument functionsMasami Hiramatsu
Cleanup the print-argument function to decouple it into print-name and print-value, so that it can support more flexible expression, like array type. Link: http://lkml.kernel.org/r/152465859635.26224.13452846788717102315.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10trace_uprobe: support reference counter in fd-based uprobeSong Liu
This patch enables uprobes with reference counter in fd-based uprobe. Highest 32 bits of perf_event_attr.config is used to stored offset of the reference count (semaphore). Format information in /sys/bus/event_source/devices/uprobe/format/ is updated to reflect this new feature. Link: http://lkml.kernel.org/r/20181002053636.1896903-1-songliubraving@fb.com Cc: Oleg Nesterov <oleg@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-09-24trace_uprobe/sdt: Prevent multiple reference counter for same uprobeRavi Bangoria
We assume to have only one reference counter for one uprobe. Don't allow user to add multiple trace_uprobe entries having same inode+offset but different reference counter. Ex, # echo "p:sdt_tick/loop2 /home/ravi/tick:0x6e4(0x10036)" > uprobe_events # echo "p:sdt_tick/loop2_1 /home/ravi/tick:0x6e4(0xfffff)" >> uprobe_events bash: echo: write error: Invalid argument # dmesg trace_kprobe: Reference counter offset mismatch. There is one exception though: When user is trying to replace the old entry with the new one, we allow this if the new entry does not conflict with any other existing entries. Link: http://lkml.kernel.org/r/20180820044250.11659-4-ravi.bangoria@linux.ibm.com Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Reviewed-by: Song Liu <songliubraving@fb.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Tested-by: Song Liu <songliubraving@fb.com> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-09-24uprobes: Support SDT markers having reference count (semaphore)Ravi Bangoria
Userspace Statically Defined Tracepoints[1] are dtrace style markers inside userspace applications. Applications like PostgreSQL, MySQL, Pthread, Perl, Python, Java, Ruby, Node.js, libvirt, QEMU, glib etc have these markers embedded in them. These markers are added by developer at important places in the code. Each marker source expands to a single nop instruction in the compiled code but there may be additional overhead for computing the marker arguments which expands to couple of instructions. In case the overhead is more, execution of it can be omitted by runtime if() condition when no one is tracing on the marker: if (reference_counter > 0) { Execute marker instructions; } Default value of reference counter is 0. Tracer has to increment the reference counter before tracing on a marker and decrement it when done with the tracing. Implement the reference counter logic in core uprobe. User will be able to use it from trace_uprobe as well as from kernel module. New trace_uprobe definition with reference counter will now be: <path>:<offset>[(ref_ctr_offset)] where ref_ctr_offset is an optional field. For kernel module, new variant of uprobe_register() has been introduced: uprobe_register_refctr(inode, offset, ref_ctr_offset, consumer) No new variant for uprobe_unregister() because it's assumed to have only one reference counter for one uprobe. [1] https://sourceware.org/systemtap/wiki/UserSpaceProbeImplementation Note: 'reference counter' is called as 'semaphore' in original Dtrace (or Systemtap, bcc and even in ELF) documentation and code. But the term 'semaphore' is misleading in this context. This is just a counter used to hold number of tracers tracing on a marker. This is not really used for any synchronization. So we are calling it a 'reference counter' in kernel / perf code. Link: http://lkml.kernel.org/r/20180820044250.11659-2-ravi.bangoria@linux.ibm.com Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> [Only trace_uprobe.c] Reviewed-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Song Liu <songliubraving@fb.com> Tested-by: Song Liu <songliubraving@fb.com> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-16tracing: Add SPDX License format tags to tracing filesSteven Rostedt (VMware)
Add the SPDX License header to ease license compliance management. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-10uprobes: Use synchronize_rcu() not synchronize_sched()Steven Rostedt (VMware)
While debugging another bug, I was looking at all the synchronize*() functions being used in kernel/trace, and noticed that trace_uprobes was using synchronize_sched(), with a comment to synchronize with {u,ret}_probe_trace_func(). When looking at those functions, the data is protected with "rcu_read_lock()" and not with "rcu_read_lock_sched()". This is using the wrong synchronize_*() function. Link: http://lkml.kernel.org/r/20180809160553.469e1e32@gandalf.local.home Cc: stable@vger.kernel.org Fixes: 70ed91c6ec7f8 ("tracing/uprobes: Support ftrace_event_file base multibuffer") Acked-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-05-24bpf: introduce bpf subcommand BPF_TASK_FD_QUERYYonghong Song
Currently, suppose a userspace application has loaded a bpf program and attached it to a tracepoint/kprobe/uprobe, and a bpf introspection tool, e.g., bpftool, wants to show which bpf program is attached to which tracepoint/kprobe/uprobe. Such attachment information will be really useful to understand the overall bpf deployment in the system. There is a name field (16 bytes) for each program, which could be used to encode the attachment point. There are some drawbacks for this approaches. First, bpftool user (e.g., an admin) may not really understand the association between the name and the attachment point. Second, if one program is attached to multiple places, encoding a proper name which can imply all these attachments becomes difficult. This patch introduces a new bpf subcommand BPF_TASK_FD_QUERY. Given a pid and fd, if the <pid, fd> is associated with a tracepoint/kprobe/uprobe perf event, BPF_TASK_FD_QUERY will return . prog_id . tracepoint name, or . k[ret]probe funcname + offset or kernel addr, or . u[ret]probe filename + offset to the userspace. The user can use "bpftool prog" to find more information about bpf program itself with prog_id. Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-04-26tracing: Fix bad use of igrab in trace_uprobe.cSong Liu
As Miklos reported and suggested: This pattern repeats two times in trace_uprobe.c and in kernel/events/core.c as well: ret = kern_path(filename, LOOKUP_FOLLOW, &path); if (ret) goto fail_address_parse; inode = igrab(d_inode(path.dentry)); path_put(&path); And it's wrong. You can only hold a reference to the inode if you have an active ref to the superblock as well (which is normally through path.mnt) or holding s_umount. This way unmounting the containing filesystem while the tracepoint is active will give you the "VFS: Busy inodes after unmount..." message and a crash when the inode is finally put. Solution: store path instead of inode. This patch fixes two instances in trace_uprobe.c. struct path is added to struct trace_uprobe to keep the inode and containing mount point referenced. Link: http://lkml.kernel.org/r/20180423172135.4050588-1-songliubraving@fb.com Fixes: f3f096cfedf8 ("tracing: Provide trace events interface for uprobes") Fixes: 33ea4b24277b ("perf/core: Implement the 'perf_uprobe' PMU") Cc: stable@vger.kernel.org Cc: Ingo Molnar <mingo@redhat.com> Cc: Howard McLauchlan <hmclauchlan@fb.com> Cc: Josef Bacik <jbacik@fb.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Miklos Szeredi <mszeredi@redhat.com> Reported-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-15Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull more perf updates from Thomas Gleixner: "A rather large set of perf updates: Kernel: - Fix various initialization issues - Prevent creating [ku]probes for not CAP_SYS_ADMIN users Tooling: - Show only failing syscalls with 'perf trace --failure' (Arnaldo Carvalho de Melo) e.g: See what 'openat' syscalls are failing: # perf trace --failure -e openat 762.323 ( 0.007 ms): VideoCapture/4566 openat(dfd: CWD, filename: /dev/video2) = -1 ENOENT No such file or directory <SNIP N /dev/videoN open attempts... sigh, where is that improvised camera lid?!? > 790.228 ( 0.008 ms): VideoCapture/4566 openat(dfd: CWD, filename: /dev/video63) = -1 ENOENT No such file or directory ^C# - Show information about the event (freq, nr_samples, total period/nr_events) in the annotate --tui and --stdio2 'perf annotate' output, similar to the first line in the 'perf report --tui', but just for the samples for a the annotated symbol (Arnaldo Carvalho de Melo) - Introduce 'perf version --build-options' to show what features were linked, aliased as well as a shorter 'perf -vv' (Jin Yao) - Add a "dso_size" sort order (Kim Phillips) - Remove redundant ')' in the tracepoint output in 'perf trace' (Changbin Du) - Synchronize x86's cpufeatures.h, no effect on toolss (Arnaldo Carvalho de Melo) - Show group details on the title line in the annotate browser and 'perf annotate --stdio2' output, so that the per-event columns can have headers (Arnaldo Carvalho de Melo) - Fixup vertical line separating metrics from instructions and cleaning unused lines at the bottom, both in the annotate TUI browser (Arnaldo Carvalho de Melo) - Remove duplicated 'samples' in lost samples warning in 'perf report' (Arnaldo Carvalho de Melo) - Synchronize i915_drm.h, silencing the perf build process, automagically adding support for the new DRM_I915_QUERY ioctl (Arnaldo Carvalho de Melo) - Make auxtrace_queues__add_buffer() allocate struct buffer, from a patchkit already applied (Adrian Hunter) - Fix the --stdio2/TUI annotate output to include group details, be it for a recorded '{a,b,f}' explicit event group or when forcing group display using 'perf report --group' for a set of events not recorded as a group (Arnaldo Carvalho de Melo) - Fix display artifacts in the ui browser (base class for the annotate and main report/top TUI browser) related to the extra title lines work (Arnaldo Carvalho de Melo) - perf auxtrace refactorings, leftovers from a previously partially processed patchset (Adrian Hunter) - Fix the builtin clang build (Sandipan Das, Arnaldo Carvalho de Melo) - Synchronize i915_drm.h, silencing a perf build warning and in the process automagically adding support for a new ioctl command (Arnaldo Carvalho de Melo) - Fix a strncpy issue in uprobe tracing" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits) perf/core: Need CAP_SYS_ADMIN to create k/uprobe with perf_event_open() tracing/uprobe_event: Fix strncpy corner case perf/core: Fix perf_uprobe_init() perf/core: Fix perf_kprobe_init() perf/core: Fix use-after-free in uprobe_perf_close() perf tests clang: Fix function name for clang IR test perf clang: Add support for recent clang versions perf tools: Fix perf builds with clang support perf tools: No need to include namespaces.h in util.h perf hists browser: Remove leftover from row returned from refresh perf hists browser: Show extra_title_lines in the 'D' debug hotkey perf auxtrace: Make auxtrace_queues__add_buffer() do CPU filtering tools headers uapi: Synchronize i915_drm.h perf report: Remove duplicated 'samples' in lost samples warning perf ui browser: Fixup cleaning unused lines at the bottom perf annotate browser: Fixup vertical line separating metrics from instructions perf annotate: Show group details on the title line perf auxtrace: Make auxtrace_queues__add_buffer() allocate struct buffer perf/x86/intel: Move regs->flags EXACT bit init perf trace: Remove redundant ')' ...
2018-04-12Merge tag 'trace-v4.17-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "A few clean ups and bug fixes: - replace open coded "ARRAY_SIZE()" with macro - updates to uprobes - bug fix for perf event filter on error path" * tag 'trace-v4.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Enforce passing in filter=NULL to create_filter() trace_uprobe: Simplify probes_seq_show() trace_uprobe: Use %lx to display offset tracing/uprobe: Add support for overlayfs tracing: Use ARRAY_SIZE() macro instead of open coding it
2018-04-11trace_uprobe: Simplify probes_seq_show()Ravi Bangoria
Simplify probes_seq_show() function. No change in output before and after patch. Link: http://lkml.kernel.org/r/20180315082756.9050-2-ravi.bangoria@linux.vnet.ibm.com Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-11trace_uprobe: Use %lx to display offsetRavi Bangoria
tu->offset is unsigned long, not a pointer, thus %lx should be used to print it, not the %px. Link: http://lkml.kernel.org/r/20180315082756.9050-1-ravi.bangoria@linux.vnet.ibm.com Cc: stable@vger.kernel.org Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Fixes: 0e4d819d0893 ("trace_uprobe: Display correct offset in uprobe_events") Suggested-by: Kees Cook <keescook@chromium.org> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-11tracing/uprobe: Add support for overlayfsHoward McLauchlan
uprobes cannot successfully attach to binaries located in a directory mounted with overlayfs. To verify, create directories for mounting overlayfs (upper,lower,work,merge), move some binary into merge/ and use readelf to obtain some known instruction of the binary. I used /bin/true and the entry instruction(0x13b0): $ mount -t overlay overlay -o lowerdir=lower,upperdir=upper,workdir=work merge $ cd /sys/kernel/debug/tracing $ echo 'p:true_entry PATH_TO_MERGE/merge/true:0x13b0' > uprobe_events $ echo 1 > events/uprobes/true_entry/enable This returns 'bash: echo: write error: Input/output error' and dmesg tells us 'event trace: Could not enable event true_entry' This change makes create_trace_uprobe() look for the real inode of a dentry. In the case of normal filesystems, this simplifies to just returning the inode. In the case of overlayfs(and similar fs) we will obtain the underlying dentry and corresponding inode, upon which uprobes can successfully register. Running the example above with the patch applied, we can see that the uprobe is enabled and will output to trace as expected. Link: http://lkml.kernel.org/r/20180410231030.2720-1-hmclauchlan@fb.com Reviewed-by: Josef Bacik <jbacik@fb.com> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Howard McLauchlan <hmclauchlan@fb.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-04-10tracing/uprobe_event: Fix strncpy corner caseMasami Hiramatsu
Fix string fetch function to terminate with NUL. It is OK to drop the rest of string. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <songliubraving@fb.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: security@kernel.org Cc: 范龙飞 <long7573@126.com> Fixes: 5baaa59ef09e ("tracing/probes: Implement 'memory' fetch method for uprobes") Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-17Merge branch 'perf/urgent' into perf/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-06perf/core: Implement the 'perf_uprobe' PMUSong Liu
This patch adds perf_uprobe support with similar pattern as previous patch (for kprobe). Two functions, create_local_trace_uprobe() and destroy_local_trace_uprobe(), are created so a uprobe can be created and attached to the file descriptor created by perf_event_open(). Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Yonghong Song <yhs@fb.com> Reviewed-by: Josef Bacik <jbacik@fb.com> Cc: <daniel@iogearbox.net> Cc: <davem@davemloft.net> Cc: <kernel-team@fb.com> Cc: <rostedt@goodmis.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20171206224518.3598254-7-songliubraving@fb.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-01-23trace_uprobe: Display correct offset in uprobe_eventsRavi Bangoria
Recently, how the pointers being printed with %p has been changed by commit ad67b74d2469 ("printk: hash addresses printed with %p"). This is causing a regression while showing offset in the uprobe_events file. Instead of %p, use %px to display offset. Before patch: # perf probe -vv -x /tmp/a.out main Opening /sys/kernel/debug/tracing//uprobe_events write=1 Writing event: p:probe_a/main /tmp/a.out:0x58c # cat /sys/kernel/debug/tracing/uprobe_events p:probe_a/main /tmp/a.out:0x0000000049a0f352 After patch: # cat /sys/kernel/debug/tracing/uprobe_events p:probe_a/main /tmp/a.out:0x000000000000058c Link: http://lkml.kernel.org/r/20180106054246.15375-1-ravi.bangoria@linux.vnet.ibm.com Cc: stable@vger.kernel.org Fixes: ad67b74d2469 ("printk: hash addresses printed with %p") Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-11-17Merge tag 'trace-v4.15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from - allow module init functions to be traced - clean up some unused or not used by config events (saves space) - clean up of trace histogram code - add support for preempt and interrupt enabled/disable events - other various clean ups * tag 'trace-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (30 commits) tracing, thermal: Hide cpu cooling trace events when not in use tracing, thermal: Hide devfreq trace events when not in use ftrace: Kill FTRACE_OPS_FL_PER_CPU perf/ftrace: Small cleanup perf/ftrace: Fix function trace events perf/ftrace: Revert ("perf/ftrace: Fix double traces of perf on ftrace:function") tracing, dma-buf: Remove unused trace event dma_fence_annotate_wait_on tracing, memcg, vmscan: Hide trace events when not in use tracing/xen: Hide events that are not used when X86_PAE is not defined tracing: mark trace_test_buffer as __maybe_unused printk: Remove superfluous memory barriers from printk_safe ftrace: Clear hashes of stale ips of init memory tracing: Add support for preempt and irq enable/disable events tracing: Prepare to add preempt and irq trace events ftrace/kallsyms: Have /proc/kallsyms show saved mod init functions ftrace: Add freeing algorithm to free ftrace_mod_maps ftrace: Save module init functions kallsyms symbols for tracing ftrace: Allow module init functions to be traced ftrace: Add a ftrace_free_mem() function for modules to use tracing: Reimplement log2 ...
2017-10-25bpf: permit multiple bpf attachments for a single perf eventYonghong Song
This patch enables multiple bpf attachments for a kprobe/uprobe/tracepoint single trace event. Each trace_event keeps a list of attached perf events. When an event happens, all attached bpf programs will be executed based on the order of attachment. A global bpf_event_mutex lock is introduced to protect prog_array attaching and detaching. An alternative will be introduce a mutex lock in every trace_event_call structure, but it takes a lot of extra memory. So a global bpf_event_mutex lock is a good compromise. The bpf prog detachment involves allocation of memory. If the allocation fails, a dummy do-nothing program will replace to-be-detached program in-place. Signed-off-by: Yonghong Song <yhs@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-16perf/ftrace: Revert ("perf/ftrace: Fix double traces of perf on ↵Peter Zijlstra
ftrace:function") Revert commit: 75e8387685f6 ("perf/ftrace: Fix double traces of perf on ftrace:function") The reason I instantly stumbled on that patch is that it only addresses the ftrace situation and doesn't mention the other _5_ places that use this interface. It doesn't explain why those don't have the problem and if not, why their solution doesn't work for ftrace. It doesn't, but this is just putting more duct tape on. Link: http://lkml.kernel.org/r/20171011080224.200565770@infradead.org Cc: Zhou Chengming <zhouchengming1@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-04tracing: Make traceprobe parsing code reusableTom Zanussi
traceprobe_probes_write() and traceprobe_command() actually contain nothing that ties them to kprobes - the code is generically useful for similar types of parsing elsewhere, so separate it out and move it to trace.c/trace.h. Other than moving it, the only change is in naming: traceprobe_probes_write() becomes trace_parse_run_command() and traceprobe_command() becomes trace_run_command(). Link: http://lkml.kernel.org/r/ae5c26ea40c196a8986854d921eb6e713ede7e3f.1506105045.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-08-29perf/ftrace: Fix double traces of perf on ftrace:functionZhou Chengming
When running perf on the ftrace:function tracepoint, there is a bug which can be reproduced by: perf record -e ftrace:function -a sleep 20 & perf record -e ftrace:function ls perf script ls 10304 [005] 171.853235: ftrace:function: perf_output_begin ls 10304 [005] 171.853237: ftrace:function: perf_output_begin ls 10304 [005] 171.853239: ftrace:function: task_tgid_nr_ns ls 10304 [005] 171.853240: ftrace:function: task_tgid_nr_ns ls 10304 [005] 171.853242: ftrace:function: __task_pid_nr_ns ls 10304 [005] 171.853244: ftrace:function: __task_pid_nr_ns We can see that all the function traces are doubled. The problem is caused by the inconsistency of the register function perf_ftrace_event_register() with the probe function perf_ftrace_function_call(). The former registers one probe for every perf_event. And the latter handles all perf_events on the current cpu. So when two perf_events on the current cpu, the traces of them will be doubled. So this patch adds an extra parameter "event" for perf_tp_event, only send sample data to this event when it's not NULL. Signed-off-by: Zhou Chengming <zhouchengming1@huawei.com> Reviewed-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: acme@kernel.org Cc: alexander.shishkin@linux.intel.com Cc: huawei.libin@huawei.com Link: http://lkml.kernel.org/r/1503668977-12526-1-git-send-email-zhouchengming1@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare to use <linux/rcuupdate.h> instead of ↵Ingo Molnar
<linux/rculist.h> in <linux/sched.h> We don't actually need the full rculist.h header in sched.h anymore, we will be able to include the smaller rcupdate.h header instead. But first update code that relied on the implicit header inclusion. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-15tracing/probe: Show subsystem name in messagesMasami Hiramatsu
Show "trace_probe:", "trace_kprobe:" and "trace_uprobe:" headers for each warning/error/info message. This will help people to notice that kprobe/uprobe events caused those messages. Link: http://lkml.kernel.org/r/148646647813.24658.16705315294927615333.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-01-17uprobe: Find last occurrence of ':' when parsing uprobe PATH:OFFSETKenny Yu
Previously, `create_trace_uprobe` found the *first* occurence of the ':' character when parsing `PATH:OFFSET` for a uprobe. However, if the path contains a ':' character, then the function would parse the path incorrectly. Even worse, if the path does not exist, the subsequent call to `kern_path()` would set `ret` to `ENOENT`, leading to very cryptic errno values in user space. The fix is to find the *last* occurence of ':'. How to repro:: The write fails with "No such file or directory", suggesting incorrectly that the `uprobe_events` file does not exist. $ mkdir testing && cd testing $ cp /bin/bash . $ cp /bin/bash ./bash:with:colon $ echo "p:uprobes/p__root_testing_bash_0x6 /root/testing/bash:0x6" > /sys/kernel/debug/tracing/uprobe_events # this works $ echo "p:uprobes/p__root_testing_bash_with_colon_0x6 /root/testing/bash:with:colon:0x6" >> /sys/kernel/debug/tracing/uprobe_events # this doesn't -bash: echo: write error: No such file or directory With the patch: $ echo "p:uprobes/p__root_testing_bash_0x6 /root/testing/bash:0x6" > /sys/kernel/debug/tracing/uprobe_events # this still works $ echo "p:uprobes/p__root_testing_bash_with_colon_0x6 /root/testing/bash:with:colon:0x6" >> /sys/kernel/debug/tracing/uprobe_events # this works now too! $ cat /sys/kernel/debug/tracing/uprobe_events p:uprobes/p__root_testing_bash_0x6 /root/testing/bash:0x0000000000000006 p:uprobes/p__root_testing_bash_with_colon_0x6 /root/testing/bash:with:colon:0x0000000000000006 Link: http://lkml.kernel.org/r/20170113165834.4081016-1-kennyyu@fb.com Signed-off-by: Kenny Yu <kennyyu@fb.com> Reviewed-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2016-10-06Merge tag 'trace-v4.9' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "This release cycle is rather small. Just a few fixes to tracing. The big change is the addition of the hwlat tracer. It not only detects SMIs, but also other latency that's caused by the hardware. I have detected some latency from large boxes having bus contention" * tag 'trace-v4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Call traceoff trigger after event is recorded ftrace/scripts: Add helper script to bisect function tracing problem functions tracing: Have max_latency be defined for HWLAT_TRACER as well tracing: Add NMI tracing in hwlat detector tracing: Have hwlat trace migrate across tracing_cpumask CPUs tracing: Add documentation for hwlat_detector tracer tracing: Added hardware latency tracer ftrace: Access ret_stack->subtime only in the function profiler function_graph: Handle TRACE_BPUTS in print_graph_comment tracing/uprobe: Drop isdigit() check in create_trace_uprobe
2016-09-01tracing/uprobe: Drop isdigit() check in create_trace_uprobeDmitry Safonov
It's useless. Before: [tracing]# echo 'p:test /a:0x0' >> uprobe_events [tracing]# echo 'p:test a:0x0' >> uprobe_events -bash: echo: write error: No such file or directory [tracing]# echo 'p:test 1:0x0' >> uprobe_events -bash: echo: write error: Invalid argument After: [tracing]# echo 'p:test 1:0x0' >> uprobe_events -bash: echo: write error: No such file or directory Link: http://lkml.kernel.org/r/20160825152110.25663-3-dsafonov@virtuozzo.com Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-08-23ftrace: kprobe: uprobe: Add x8/x16/x32/x64 for hexadecimal typesMasami Hiramatsu
Add x8/x16/x32/x64 for hexadecimal type casting to kprobe/uprobe event tracer. These type casts can be used for integer arguments for explicitly showing them in hexadecimal digits in formatted text. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Hemant Kumar <hemant@linux.vnet.ibm.com> Cc: Naohiro Aota <naohiro.aota@hgst.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/r/147151067029.12957.11591314629326414783.stgit@devbox Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-07perf: split perf_trace_buf_prepare into alloc and update partsAlexei Starovoitov
split allows to move expensive update of 'struct trace_entry' to later phase. Repurpose unused 1st argument of perf_tp_event() to indicate event type. While splitting use temp variable 'rctx' instead of '*rctx' to avoid unnecessary loads done by the compiler due to -fno-strict-aliasing Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-22kernel/...: convert pr_warning to pr_warnJoe Perches
Use the more common logging method with the eventual goal of removing pr_warning altogether. Miscellanea: - Realign arguments - Coalesce formats - Add missing space between a few coalesced formats Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [kernel/power/suspend.c] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-08-26tracing/uprobes: Do not print '0x (null)' when offset is 0Wang Nan
When manually added uprobe point with zero address, 'uprobe_events' output '(null)' instead of 0x00000000: # echo p:probe_libc/abs_0 /path/to/lib.bin:0x0 arg1=%ax > \ /sys/kernel/debug/tracing/uprobe_events # cat /sys/kernel/debug/tracing/uprobe_events p:probe_libc/abs_0 /path/to/lib.bin:0x (null) arg1=%ax This patch fixes this behavior: # cat /sys/kernel/debug/tracing/uprobe_events p:probe_libc/abs_0 /path/to/lib.bin:0x0000000000000000 Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1440586666-235233-8-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-08-06tracing, perf: Implement BPF programs attached to uprobesWang Nan
By copying BPF related operation to uprobe processing path, this patch allow users attach BPF programs to uprobes like what they are already doing on kprobes. After this patch, users are allowed to use PERF_EVENT_IOC_SET_BPF on a uprobe perf event. Which make it possible to profile user space programs and kernel events together using BPF. Because of this patch, CONFIG_BPF_EVENTS should be selected by CONFIG_UPROBE_EVENT to ensure trace_call_bpf() is compiled even if KPROBE_EVENT is not set. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1435716878-189507-3-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-13tracing: Rename ftrace_trigger_soft_disabled() to trace_trigger_soft_disabled()Steven Rostedt (Red Hat)
The name "ftrace" really refers to the function hook infrastructure. It is not about the trace_events. The ftrace_trigger_soft_disabled() tests if a trace_event is soft disabled (called but not traced), and returns true if it is. It has nothing to do with function tracing and should be renamed. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
generated by cgit (git 2.34.1) at 2024-05-30 21:02:40 +0000