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2019-06-25tracing: Silence GCC 9 array bounds warningMiguel Ojeda
commit 0c97bf863efce63d6ab7971dad811601e6171d2f upstream. Starting with GCC 9, -Warray-bounds detects cases when memset is called starting on a member of a struct but the size to be cleared ends up writing over further members. Such a call happens in the trace code to clear, at once, all members after and including `seq` on struct trace_iterator: In function 'memset', inlined from 'ftrace_dump' at kernel/trace/trace.c:8914:3: ./include/linux/string.h:344:9: warning: '__builtin_memset' offset [8505, 8560] from the object at 'iter' is out of the bounds of referenced subobject 'seq' with type 'struct trace_seq' at offset 4368 [-Warray-bounds] 344 | return __builtin_memset(p, c, size); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ In order to avoid GCC complaining about it, we compute the address ourselves by adding the offsetof distance instead of referring directly to the member. Since there are two places doing this clear (trace.c and trace_kdb.c), take the chance to move the workaround into a single place in the internal header. Link: http://lkml.kernel.org/r/20190523124535.GA12931@gmail.com Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> [ Removed unnecessary parenthesis around "iter" ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19tracing/uprobe: Fix NULL pointer dereference in trace_uprobe_create()Eiichi Tsukata
commit f01098c74b5219f3969d4750eeed1a36bfc038e3 upstream. Just like the case of commit 8b05a3a7503c ("tracing/kprobes: Fix NULL pointer dereference in trace_kprobe_create()"), writing an incorrectly formatted string to uprobe_events can trigger NULL pointer dereference. Reporeducer: # echo r > /sys/kernel/debug/tracing/uprobe_events dmesg: BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 8000000079d12067 P4D 8000000079d12067 PUD 7b7ab067 PMD 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 0 PID: 1903 Comm: bash Not tainted 5.2.0-rc3+ #15 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-2.fc30 04/01/2014 RIP: 0010:strchr+0x0/0x30 Code: c0 eb 0d 84 c9 74 18 48 83 c0 01 48 39 d0 74 0f 0f b6 0c 07 3a 0c 06 74 ea 19 c0 83 c8 01 c3 31 c0 c3 0f 1f 84 00 00 00 00 00 <0f> b6 07 89 f2 40 38 f0 75 0e eb 13 0f b6 47 01 48 83 c RSP: 0018:ffffb55fc0403d10 EFLAGS: 00010293 RAX: ffff993ffb793400 RBX: 0000000000000000 RCX: ffffffffa4852625 RDX: 0000000000000000 RSI: 000000000000002f RDI: 0000000000000000 RBP: ffffb55fc0403dd0 R08: ffff993ffb793400 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff993ff9cc1668 R14: 0000000000000001 R15: 0000000000000000 FS: 00007f30c5147700(0000) GS:ffff993ffda00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000007b628000 CR4: 00000000000006f0 Call Trace: trace_uprobe_create+0xe6/0xb10 ? __kmalloc_track_caller+0xe6/0x1c0 ? __kmalloc+0xf0/0x1d0 ? trace_uprobe_create+0xb10/0xb10 create_or_delete_trace_uprobe+0x35/0x90 ? trace_uprobe_create+0xb10/0xb10 trace_run_command+0x9c/0xb0 trace_parse_run_command+0xf9/0x1eb ? probes_open+0x80/0x80 __vfs_write+0x43/0x90 vfs_write+0x14a/0x2a0 ksys_write+0xa2/0x170 do_syscall_64+0x7f/0x200 entry_SYSCALL_64_after_hwframe+0x49/0xbe Link: http://lkml.kernel.org/r/20190614074026.8045-1-devel@etsukata.com Cc: stable@vger.kernel.org Fixes: 0597c49c69d5 ("tracing/uprobes: Use dyn_event framework for uprobe events") Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Eiichi Tsukata <devel@etsukata.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19tracing: Prevent hist_field_var_ref() from accessing NULL tracing_map_eltsTom Zanussi
[ Upstream commit 55267c88c003a3648567beae7c90512d3e2ab15e ] hist_field_var_ref() is an implementation of hist_field_fn_t(), which can be called with a null tracing_map_elt elt param when assembling a key in event_hist_trigger(). In the case of hist_field_var_ref() this doesn't make sense, because a variable can only be resolved by looking it up using an already assembled key i.e. a variable can't be used to assemble a key since the key is required in order to access the variable. Upper layers should prevent the user from constructing a key using a variable in the first place, but in case one slips through, it shouldn't cause a NULL pointer dereference. Also if one does slip through, we want to know about it, so emit a one-time warning in that case. Link: http://lkml.kernel.org/r/64ec8dc15c14d305295b64cdfcc6b2b9dd14753f.1555597045.git.tom.zanussi@linux.intel.com Reported-by: Vincent Bernat <vincent@bernat.ch> Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-06-09tracing: Avoid memory leak in predicate_parse()Tomas Bortoli
commit dfb4a6f2191a80c8b790117d0ff592fd712d3296 upstream. In case of errors, predicate_parse() goes to the out_free label to free memory and to return an error code. However, predicate_parse() does not free the predicates of the temporary prog_stack array, thence leaking them. Link: http://lkml.kernel.org/r/20190528154338.29976-1-tomasbortoli@gmail.com Cc: stable@vger.kernel.org Fixes: 80765597bc587 ("tracing: Rewrite filter logic to be simpler and faster") Reported-by: syzbot+6b8e0fb820e570c59e19@syzkaller.appspotmail.com Signed-off-by: Tomas Bortoli <tomasbortoli@gmail.com> [ Added protection around freeing prog_stack[i].pred ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-31x86/uaccess, ftrace: Fix ftrace_likely_update() vs. SMAPPeter Zijlstra
[ Upstream commit 4a6c91fbdef846ec7250b82f2eeeb87ac5f18cf9 ] For CONFIG_TRACE_BRANCH_PROFILING=y the likely/unlikely things get overloaded and generate callouts to this code, and thus also when AC=1. Make it safe. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-05-31tracing: Add a check_val() check before updating cond_snapshot() track_valTom Zanussi
commit 9b2ca371b1505a547217b244f903ad3fb86fa5b4 upstream. Without this check a snapshot is taken whenever a bucket's max is hit, rather than only when the global max is hit, as it should be. Before: In this example, we do a first run of the workload (cyclictest), examine the output, note the max ('triggering value') (347), then do a second run and note the max again. In this case, the max in the second run (39) is below the max in the first run, but since we haven't cleared the histogram, the first max is still in the histogram and is higher than any other max, so it should still be the max for the snapshot. It isn't however - the value should still be 347 after the second run. # echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_waking/trigger # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0:onmax($wakeup_lat).save(next_prio,next_comm,prev_pid,prev_prio,prev_comm):onmax($wakeup_lat).snapshot() if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger # cyclictest -p 80 -n -s -t 2 -D 2 # cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist { next_pid: 2143 } hitcount: 199 max: 44 next_prio: 120 next_comm: cyclictest prev_pid: 0 prev_prio: 120 prev_comm: swapper/4 { next_pid: 2145 } hitcount: 1325 max: 38 next_prio: 19 next_comm: cyclictest prev_pid: 0 prev_prio: 120 prev_comm: swapper/2 { next_pid: 2144 } hitcount: 1982 max: 347 next_prio: 19 next_comm: cyclictest prev_pid: 0 prev_prio: 120 prev_comm: swapper/6 Snapshot taken (see tracing/snapshot). Details: triggering value { onmax($wakeup_lat) }: 347 triggered by event with key: { next_pid: 2144 } # cyclictest -p 80 -n -s -t 2 -D 2 # cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist { next_pid: 2143 } hitcount: 199 max: 44 next_prio: 120 next_comm: cyclictest prev_pid: 0 prev_prio: 120 prev_comm: swapper/4 { next_pid: 2148 } hitcount: 199 max: 16 next_prio: 120 next_comm: cyclictest prev_pid: 0 prev_prio: 120 prev_comm: swapper/1 { next_pid: 2145 } hitcount: 1325 max: 38 next_prio: 19 next_comm: cyclictest prev_pid: 0 prev_prio: 120 prev_comm: swapper/2 { next_pid: 2150 } hitcount: 1326 max: 39 next_prio: 19 next_comm: cyclictest prev_pid: 0 prev_prio: 120 prev_comm: swapper/4 { next_pid: 2144 } hitcount: 1982 max: 347 next_prio: 19 next_comm: cyclictest prev_pid: 0 prev_prio: 120 prev_comm: swapper/6 { next_pid: 2149 } hitcount: 1983 max: 130 next_prio: 19 next_comm: cyclictest prev_pid: 0 prev_prio: 120 prev_comm: swapper/0 Snapshot taken (see tracing/snapshot). Details: triggering value { onmax($wakeup_lat) }: 39 triggered by event with key: { next_pid: 2150 } After: In this example, we do a first run of the workload (cyclictest), examine the output, note the max ('triggering value') (375), then do a second run and note the max again. In this case, the max in the second run is still 375, the highest in any bucket, as it should be. # cyclictest -p 80 -n -s -t 2 -D 2 # cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist { next_pid: 2072 } hitcount: 200 max: 28 next_prio: 120 next_comm: cyclictest prev_pid: 0 prev_prio: 120 prev_comm: swapper/5 { next_pid: 2074 } hitcount: 1323 max: 375 next_prio: 19 next_comm: cyclictest prev_pid: 0 prev_prio: 120 prev_comm: swapper/2 { next_pid: 2073 } hitcount: 1980 max: 153 next_prio: 19 next_comm: cyclictest prev_pid: 0 prev_prio: 120 prev_comm: swapper/6 Snapshot taken (see tracing/snapshot). Details: triggering value { onmax($wakeup_lat) }: 375 triggered by event with key: { next_pid: 2074 } # cyclictest -p 80 -n -s -t 2 -D 2 # cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist { next_pid: 2101 } hitcount: 199 max: 49 next_prio: 120 next_comm: cyclictest prev_pid: 0 prev_prio: 120 prev_comm: swapper/6 { next_pid: 2072 } hitcount: 200 max: 28 next_prio: 120 next_comm: cyclictest prev_pid: 0 prev_prio: 120 prev_comm: swapper/5 { next_pid: 2074 } hitcount: 1323 max: 375 next_prio: 19 next_comm: cyclictest prev_pid: 0 prev_prio: 120 prev_comm: swapper/2 { next_pid: 2103 } hitcount: 1325 max: 74 next_prio: 19 next_comm: cyclictest prev_pid: 0 prev_prio: 120 prev_comm: swapper/4 { next_pid: 2073 } hitcount: 1980 max: 153 next_prio: 19 next_comm: cyclictest prev_pid: 0 prev_prio: 120 prev_comm: swapper/6 { next_pid: 2102 } hitcount: 1981 max: 84 next_prio: 19 next_comm: cyclictest prev_pid: 12 prev_prio: 120 prev_comm: kworker/0:1 Snapshot taken (see tracing/snapshot). Details: triggering value { onmax($wakeup_lat) }: 375 triggered by event with key: { next_pid: 2074 } Link: http://lkml.kernel.org/r/95958351329f129c07504b4d1769c47a97b70d65.1555597045.git.tom.zanussi@linux.intel.com Cc: stable@vger.kernel.org Fixes: a3785b7eca8fd ("tracing: Add hist trigger snapshot() action") Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-25tracing: probeevent: Fix to make the type of $comm stringMasami Hiramatsu
commit 3dd1f7f24f8ceec00bbbc364c2ac3c893f0fdc4c upstream. Fix to make the type of $comm "string". If we set the other type to $comm argument, it shows meaningless value or wrong data. Currently probe events allow us to set string array type (e.g. ":string[2]"), or other digit types like x8 on $comm. But since clearly $comm is just a string data, it should not be fetched by other types including array. Link: http://lkml.kernel.org/r/155723736241.9149.14582064184468574539.stgit@devnote2 Cc: Andreas Ziegler <andreas.ziegler@fau.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: stable@vger.kernel.org Fixes: 533059281ee5 ("tracing: probeevent: Introduce new argument fetching code") Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-25tracing: Fix partial reading of trace event's id fileElazar Leibovich
commit cbe08bcbbe787315c425dde284dcb715cfbf3f39 upstream. When reading only part of the id file, the ppos isn't tracked correctly. This is taken care by simple_read_from_buffer. Reading a single byte, and then the next byte would result EOF. While this seems like not a big deal, this breaks abstractions that reads information from files unbuffered. See for example https://github.com/golang/go/issues/29399 This code was mentioned as problematic in commit cd458ba9d5a5 ("tracing: Do not (ab)use trace_seq in event_id_read()") An example C code that show this bug is: #include <stdio.h> #include <stdint.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <unistd.h> int main(int argc, char **argv) { if (argc < 2) return 1; int fd = open(argv[1], O_RDONLY); char c; read(fd, &c, 1); printf("First %c\n", c); read(fd, &c, 1); printf("Second %c\n", c); } Then run with, e.g. sudo ./a.out /sys/kernel/debug/tracing/events/tcp/tcp_set_state/id You'll notice you're getting the first character twice, instead of the first two characters in the id file. Link: http://lkml.kernel.org/r/20181231115837.4932-1-elazar@lightbitslabs.com Cc: Orit Wasserman <orit.was@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: stable@vger.kernel.org Fixes: 23725aeeab10b ("ftrace: provide an id file for each event") Signed-off-by: Elazar Leibovich <elazar@lightbitslabs.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-26Merge tag 'trace-v5.1-rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "Three tracing fixes: - Use "nosteal" for ring buffer splice pages - Memory leak fix in error path of trace_pid_write() - Fix preempt_enable_no_resched() (use preempt_enable()) in ring buffer code" * tag 'trace-v5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: trace: Fix preempt_enable_no_resched() abuse tracing: Fix a memory leak by early error exit in trace_pid_write() tracing: Fix buffer_ref pipe ops
2019-04-26trace: Fix preempt_enable_no_resched() abusePeter Zijlstra
Unless the very next line is schedule(), or implies it, one must not use preempt_enable_no_resched(). It can cause a preemption to go missing and thereby cause arbitrary delays, breaking the PREEMPT=y invariant. Link: http://lkml.kernel.org/r/20190423200318.GY14281@hirez.programming.kicks-ass.net Cc: Waiman Long <longman@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: the arch/x86 maintainers <x86@kernel.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: huang ying <huang.ying.caritas@gmail.com> Cc: Roman Gushchin <guro@fb.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: stable@vger.kernel.org Fixes: 2c2d7329d8af ("tracing/ftrace: use preempt_enable_no_resched_notrace in ring_buffer_time_stamp()") Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-26tracing: Fix a memory leak by early error exit in trace_pid_write()Wenwen Wang
In trace_pid_write(), the buffer for trace parser is allocated through kmalloc() in trace_parser_get_init(). Later on, after the buffer is used, it is then freed through kfree() in trace_parser_put(). However, it is possible that trace_pid_write() is terminated due to unexpected errors, e.g., ENOMEM. In that case, the allocated buffer will not be freed, which is a memory leak bug. To fix this issue, free the allocated buffer when an error is encountered. Link: http://lkml.kernel.org/r/1555726979-15633-1-git-send-email-wang6495@umn.edu Fixes: f4d34a87e9c10 ("tracing: Use pid bitmap instead of a pid array for set_event_pid") Cc: stable@vger.kernel.org Signed-off-by: Wenwen Wang <wang6495@umn.edu> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-26tracing: Fix buffer_ref pipe opsJann Horn
This fixes multiple issues in buffer_pipe_buf_ops: - The ->steal() handler must not return zero unless the pipe buffer has the only reference to the page. But generic_pipe_buf_steal() assumes that every reference to the pipe is tracked by the page's refcount, which isn't true for these buffers - buffer_pipe_buf_get(), which duplicates a buffer, doesn't touch the page's refcount. Fix it by using generic_pipe_buf_nosteal(), which refuses every attempted theft. It should be easy to actually support ->steal, but the only current users of pipe_buf_steal() are the virtio console and FUSE, and they also only use it as an optimization. So it's probably not worth the effort. - The ->get() and ->release() handlers can be invoked concurrently on pipe buffers backed by the same struct buffer_ref. Make them safe against concurrency by using refcount_t. - The pointers stored in ->private were only zeroed out when the last reference to the buffer_ref was dropped. As far as I know, this shouldn't be necessary anyway, but if we do it, let's always do it. Link: http://lkml.kernel.org/r/20190404215925.253531-1-jannh@google.com Cc: Ingo Molnar <mingo@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: stable@vger.kernel.org Fixes: 73a757e63114d ("ring-buffer: Return reader page back into existing ring buffer") Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-19kprobes: Mark ftrace mcount handler functions nokprobeMasami Hiramatsu
Mark ftrace mcount handler functions nokprobe since probing on these functions with kretprobe pushes return address incorrectly on kretprobe shadow stack. Reported-by: Francis Deslauriers <francis.deslauriers@efficios.com> Tested-by: Andrea Righi <righi.andrea@gmail.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/155094062044.6137.6419622920568680640.stgit@devbox Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-14Merge branch 'page-refs' (page ref overflow)Linus Torvalds
Merge page ref overflow branch. Jann Horn reported that he can overflow the page ref count with sufficient memory (and a filesystem that is intentionally extremely slow). Admittedly it's not exactly easy. To have more than four billion references to a page requires a minimum of 32GB of kernel memory just for the pointers to the pages, much less any metadata to keep track of those pointers. Jann needed a total of 140GB of memory and a specially crafted filesystem that leaves all reads pending (in order to not ever free the page references and just keep adding more). Still, we have a fairly straightforward way to limit the two obvious user-controllable sources of page references: direct-IO like page references gotten through get_user_pages(), and the splice pipe page duplication. So let's just do that. * branch page-refs: fs: prevent page refcount overflow in pipe_buf_get mm: prevent get_user_pages() from overflowing page refcount mm: add 'try_get_page()' helper function mm: make page ref count overflow check tighter and more explicit
2019-04-14fs: prevent page refcount overflow in pipe_buf_getMatthew Wilcox
Change pipe_buf_get() to return a bool indicating whether it succeeded in raising the refcount of the page (if the thing in the pipe is a page). This removes another mechanism for overflowing the page refcount. All callers converted to handle a failure. Reported-by: Jann Horn <jannh@google.com> Signed-off-by: Matthew Wilcox <willy@infradead.org> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-04-05syscalls: Remove start and number from syscall_get_arguments() argsSteven Rostedt (Red Hat)
At Linux Plumbers, Andy Lutomirski approached me and pointed out that the function call syscall_get_arguments() implemented in x86 was horribly written and not optimized for the standard case of passing in 0 and 6 for the starting index and the number of system calls to get. When looking at all the users of this function, I discovered that all instances pass in only 0 and 6 for these arguments. Instead of having this function handle different cases that are never used, simply rewrite it to return the first 6 arguments of a system call. This should help out the performance of tracing system calls by ptrace, ftrace and perf. Link: http://lkml.kernel.org/r/20161107213233.754809394@goodmis.org Cc: Oleg Nesterov <oleg@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Dave Martin <dave.martin@arm.com> Cc: "Dmitry V. Levin" <ldv@altlinux.org> Cc: x86@kernel.org Cc: linux-snps-arc@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-c6x-dev@linux-c6x.org Cc: uclinux-h8-devel@lists.sourceforge.jp Cc: linux-hexagon@vger.kernel.org Cc: linux-ia64@vger.kernel.org Cc: linux-mips@vger.kernel.org Cc: nios2-dev@lists.rocketboards.org Cc: openrisc@lists.librecores.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-riscv@lists.infradead.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: sparclinux@vger.kernel.org Cc: linux-um@lists.infradead.org Cc: linux-xtensa@linux-xtensa.org Cc: linux-arch@vger.kernel.org Acked-by: Paul Burton <paul.burton@mips.com> # MIPS parts Acked-by: Max Filippov <jcmvbkbc@gmail.com> # For xtensa changes Acked-by: Will Deacon <will.deacon@arm.com> # For the arm64 bits Reviewed-by: Thomas Gleixner <tglx@linutronix.de> # for x86 Reviewed-by: Dmitry V. Levin <ldv@altlinux.org> Reported-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-04tracing/syscalls: Pass in hardcoded 6 into syscall_get_arguments()Steven Rostedt (Red Hat)
The only users that calls syscall_get_arguments() with a variable and not a hard coded '6' is ftrace_syscall_enter(). syscall_get_arguments() can be optimized by removing a variable input, and always grabbing 6 arguments regardless of what the system call actually uses. Change ftrace_syscall_enter() to pass the 6 args into a local stack array and copy the necessary arguments into the trace event as needed. This is needed to remove two parameters from syscall_get_arguments(). Link: http://lkml.kernel.org/r/20161107213233.627583542@goodmis.org Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-26ftrace: Fix warning using plain integer as NULL & spelling correctionsHariprasad Kelam
Changed 0 --> NULL to avoid sparse warning Corrected spelling mistakes reported by checkpatch.pl Sparse warning below: sudo make C=2 CF=-D__CHECK_ENDIAN__ M=kernel/trace CHECK kernel/trace/ftrace.c kernel/trace/ftrace.c:3007:24: warning: Using plain integer as NULL pointer kernel/trace/ftrace.c:4758:37: warning: Using plain integer as NULL pointer Link: http://lkml.kernel.org/r/20190323183523.GA2244@hari-Inspiron-1545 Signed-off-by: Hariprasad Kelam <hariprasad.kelam@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-26tracing: initialize variable in create_dyn_event()Frank Rowand
Fix compile warning in create_dyn_event(): 'ret' may be used uninitialized in this function [-Wuninitialized]. Link: http://lkml.kernel.org/r/1553237900-8555-1-git-send-email-frowand.list@gmail.com Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Tom Zanussi <tom.zanussi@linux.intel.com> Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com> Cc: stable@vger.kernel.org Fixes: 5448d44c3855 ("tracing: Add unified dynamic event framework") Signed-off-by: Frank Rowand <frank.rowand@sony.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-26tracing: Remove unnecessary var_ref destroy in track_data_destroy()Tom Zanussi
Commit 656fe2ba85e8 (tracing: Use hist trigger's var_ref array to destroy var_refs) centralized the destruction of all the var_refs in one place so that other code didn't have to do it. The track_data_destroy() added later ignored that and also destroyed the track_data var_ref, causing a double-free error flagged by KASAN. ================================================================== BUG: KASAN: use-after-free in destroy_hist_field+0x30/0x70 Read of size 8 at addr ffff888086df2210 by task bash/1694 CPU: 6 PID: 1694 Comm: bash Not tainted 5.1.0-rc1-test+ #15 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016 Call Trace: dump_stack+0x71/0xa0 ? destroy_hist_field+0x30/0x70 print_address_description.cold.3+0x9/0x1fb ? destroy_hist_field+0x30/0x70 ? destroy_hist_field+0x30/0x70 kasan_report.cold.4+0x1a/0x33 ? __kasan_slab_free+0x100/0x150 ? destroy_hist_field+0x30/0x70 destroy_hist_field+0x30/0x70 track_data_destroy+0x55/0xe0 destroy_hist_data+0x1f0/0x350 hist_unreg_all+0x203/0x220 event_trigger_open+0xbb/0x130 do_dentry_open+0x296/0x700 ? stacktrace_count_trigger+0x30/0x30 ? generic_permission+0x56/0x200 ? __x64_sys_fchdir+0xd0/0xd0 ? inode_permission+0x55/0x200 ? security_inode_permission+0x18/0x60 path_openat+0x633/0x22b0 ? path_lookupat.isra.50+0x420/0x420 ? __kasan_kmalloc.constprop.12+0xc1/0xd0 ? kmem_cache_alloc+0xe5/0x260 ? getname_flags+0x6c/0x2a0 ? do_sys_open+0x149/0x2b0 ? do_syscall_64+0x73/0x1b0 ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 ? _raw_write_lock_bh+0xe0/0xe0 ? __kernel_text_address+0xe/0x30 ? unwind_get_return_address+0x2f/0x50 ? __list_add_valid+0x2d/0x70 ? deactivate_slab.isra.62+0x1f4/0x5a0 ? getname_flags+0x6c/0x2a0 ? set_track+0x76/0x120 do_filp_open+0x11a/0x1a0 ? may_open_dev+0x50/0x50 ? _raw_spin_lock+0x7a/0xd0 ? _raw_write_lock_bh+0xe0/0xe0 ? __alloc_fd+0x10f/0x200 do_sys_open+0x1db/0x2b0 ? filp_open+0x50/0x50 do_syscall_64+0x73/0x1b0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7fa7b24a4ca2 Code: 25 00 00 41 00 3d 00 00 41 00 74 4c 48 8d 05 85 7a 0d 00 8b 00 85 c0 75 6d 89 f2 b8 01 01 00 00 48 89 fe bf 9c ff ff ff 0f 05 <48> 3d 00 f0 ff ff 0f 87 a2 00 00 00 48 8b 4c 24 28 64 48 33 0c 25 RSP: 002b:00007fffbafb3af0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000055d3648ade30 RCX: 00007fa7b24a4ca2 RDX: 0000000000000241 RSI: 000055d364a55240 RDI: 00000000ffffff9c RBP: 00007fffbafb3bf0 R08: 0000000000000020 R09: 0000000000000002 R10: 00000000000001b6 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000001 R15: 000055d364a55240 ================================================================== So remove the track_data_destroy() destroy_hist_field() call for that var_ref. Link: http://lkml.kernel.org/r/1deffec420f6a16d11dd8647318d34a66d1989a9.camel@linux.intel.com Fixes: 466f4528fbc69 ("tracing: Generalize hist trigger onmax and save action") Reported-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-16Merge tag 'for-5.1/block-post-20190315' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull more block layer changes from Jens Axboe: "This is a collection of both stragglers, and fixes that came in after I finalized the initial pull. This contains: - An MD pull request from Song, with a few minor fixes - Set of NVMe patches via Christoph - Pull request from Konrad, with a few fixes for xen/blkback - pblk fix IO calculation fix (Javier) - Segment calculation fix for pass-through (Ming) - Fallthrough annotation for blkcg (Mathieu)" * tag 'for-5.1/block-post-20190315' of git://git.kernel.dk/linux-block: (25 commits) blkcg: annotate implicit fall through nvme-tcp: support C2HData with SUCCESS flag nvmet: ignore EOPNOTSUPP for discard nvme: add proper write zeroes setup for the multipath device nvme: add proper discard setup for the multipath device nvme: remove nvme_ns_config_oncs nvme: disable Write Zeroes for qemu controllers nvmet-fc: bring Disconnect into compliance with FC-NVME spec nvmet-fc: fix issues with targetport assoc_list list walking nvme-fc: reject reconnect if io queue count is reduced to zero nvme-fc: fix numa_node when dev is null nvme-fc: use nr_phys_segments to determine existence of sgl nvme-loop: init nvmet_ctrl fatal_err_work when allocate nvme: update comment to make the code easier to read nvme: put ns_head ref if namespace fails allocation nvme-trace: fix cdw10 buffer overrun nvme: don't warn on block content change effects nvme: add get-feature to admin cmds tracer md: Fix failed allocation of md_register_thread It's wrong to add len to sector_nr in raid10 reshape twice ...
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>
2019-03-14tracing/probe: Check the size of argument name and bodyMasami Hiramatsu
Check the size of argument name and expression is not 0 and smaller than maximum length. Link: http://lkml.kernel.org/r/155253783029.14922.12650939303827581096.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 name length correctlyMasami Hiramatsu
Ensure given name of event is not too long when parsing it, and fix to update event name offset correctly when the group name is given. For example, this makes probe event to check the "p:foo/" error case correctly. Link: http://lkml.kernel.org/r/155253782046.14922.14724124823730168629.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-14tracing/probe: Check maxactive error casesMasami Hiramatsu
Check maxactive on kprobe error case, because maxactive is only for kretprobe, not for kprobe. Also, maxactive should not be 0, it should be at least 1. Link: http://lkml.kernel.org/r/155253780952.14922.15784129810238750331.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-13blkcg: annotate implicit fall throughMathieu Malaterre
There is a plan to build the kernel with -Wimplicit-fallthrough and this place in the code produced a warning (W=1). This commit remove the following warning: kernel/trace/blktrace.c:725:9: warning: this statement may fall through [-Wimplicit-fallthrough=] Signed-off-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-03-13tracing: kdb: Fix ftdump to not sleepDouglas Anderson
As reported back in 2016-11 [1], the "ftdump" kdb command triggers a BUG for "sleeping function called from invalid context". kdb's "ftdump" command wants to call ring_buffer_read_prepare() in atomic context. A very simple solution for this is to add allocation flags to ring_buffer_read_prepare() so kdb can call it without triggering the allocation error. This patch does that. Note that in the original email thread about this, it was suggested that perhaps the solution for kdb was to either preallocate the buffer ahead of time or create our own iterator. I'm hoping that this alternative of adding allocation flags to ring_buffer_read_prepare() can be considered since it means I don't need to duplicate more of the core trace code into "trace_kdb.c" (for either creating my own iterator or re-preparing a ring allocator whose memory was already allocated). NOTE: another option for kdb is to actually figure out how to make it reuse the existing ftrace_dump() function and totally eliminate the duplication. This sounds very appealing and actually works (the "sr z" command can be seen to properly dump the ftrace buffer). The downside here is that ftrace_dump() fully consumes the trace buffer. Unless that is changed I'd rather not use it because it means "ftdump | grep xyz" won't be very useful to search the ftrace buffer since it will throw away the whole trace on the first grep. A future patch to dump only the last few lines of the buffer will also be hard to implement. [1] https://lkml.kernel.org/r/20161117191605.GA21459@google.com Link: http://lkml.kernel.org/r/20190308193205.213659-1-dianders@chromium.org Reported-by: Brian Norris <briannorris@chromium.org> Signed-off-by: Douglas Anderson <dianders@chromium.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-12Merge branch 'work.misc' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc vfs updates from Al Viro: "Assorted fixes (really no common topic here)" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: vfs: Make __vfs_write() static vfs: fix preadv64v2 and pwritev64v2 compat syscalls with offset == -1 pipe: stop using ->can_merge splice: don't merge into linked buffers fs: move generic stat response attr handling to vfs_getattr_nosec orangefs: don't reinitialize result_mask in ->getattr fs/devpts: always delete dcache dentry-s in dput()
2019-03-12trace/probes: Remove kernel doc style from non kernel doc commentValdis Klētnieks
CC kernel/trace/trace_kprobe.o kernel/trace/trace_kprobe.c:41: warning: cannot understand function prototype: 'struct trace_kprobe ' The real problem is that a comment looked like kerneldoc when it shouldn't be... Link: http://lkml.kernel.org/r/2812.1552381112@turing-police Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-12tracing/probes: Make reserved_field_names staticValdis Klētnieks
sparse complains: CHECK kernel/trace/trace_probe.c kernel/trace/trace_probe.c:16:12: warning: symbol 'reserved_field_names' was not declared. Should it be static? Yes, it should be static. Link: http://lkml.kernel.org/r/2478.1552380778@turing-police Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-11Merge tag 'trace-v5.1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "The biggest change for this release is in the histogram code: - Add "onchange(var)" histogram handler that executes a action when $var changes. - Add new "snapshot()" action for histogram handlers, that causes a snapshot of the ring buffer when triggered. ie. onchange(var).snapshot() will trigger a snapshot if var changes. - Add alternative for "trace()" action. Currently, to trigger a synthetic event, the name of that event is used as the handler name, which is inconsistent with the other actions. onchange(var).synthetic(param) where it can now be onchange(var).trace(synthetic, param). The older method will still be allowed, as long as the synthetic events do not overlap with other handler names. - The histogram documentation at testcases were updated for the new changes. Outside of the histogram code, we have: - Added a quicker way to enable set_ftrace_filter files, that will make it much quicker to bisect tracing a function that shouldn't be traced and crashes the kernel. (You can echo in numbers to set_ftrace_filter, and it will select the corresponding function that is in available_filter_functions). - Some better displaying of the tracing data (and more information was added). The rest are small fixes and more clean ups to the code" * tag 'trace-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (37 commits) tracing: Use strncpy instead of memcpy when copying comm in trace.c tracing: Use strncpy instead of memcpy when copying comm for hist triggers tracing: Use strncpy instead of memcpy for string keys in hist triggers tracing: Use str_has_prefix() in synth_event_create() x86/ftrace: Fix warning and considate ftrace_jmp_replace() and ftrace_call_replace() tracing/perf: Use strndup_user() instead of buggy open-coded version doc: trace: Fix documentation for uprobe_profile tracing: Fix spelling mistake: "analagous" -> "analogous" tracing: Comment why cond_snapshot is checked outside of max_lock protection tracing: Add hist trigger action 'expected fail' test case tracing: Add alternative synthetic event trace action test case tracing: Add hist trigger onchange() handler test case tracing: Add hist trigger snapshot() action test case tracing: Add SPDX license GPL-2.0 license identifier to inter-event testcases tracing: Add alternative synthetic event trace action syntax tracing: Add hist trigger onchange() handler Documentation tracing: Add hist trigger onchange() handler tracing: Add hist trigger snapshot() action Documentation tracing: Add hist trigger snapshot() action tracing: Add conditional snapshot ...
2019-03-10Merge tag 'kbuild-v5.1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - do not generate unneeded top-level built-in.a - let git ignore O= directory entirely - optimize scripts/kallsyms slightly - exclude DWARF info from *.s regardless of config options - fix GCC toolchain search path for Clang to prepare ld.lld support - do not generate modules.order when CONFIG_MODULES is disabled - simplify single target rules and remove VPATH for external module build - allow to add optional flags to dpkg-buildpackage when building deb-pkg - move some compiler option tests from Makefile to Kconfig - various Makefile cleanups * tag 'kbuild-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (40 commits) kbuild: remove scripts/basic/% build target kbuild: use -Werror=implicit-... instead of -Werror-implicit-... kbuild: clean up scripts/gcc-version.sh kbuild: remove cc-version macro kbuild: update comment block of scripts/clang-version.sh kbuild: remove commented-out INITRD_COMPRESS kbuild: move -gsplit-dwarf, -gdwarf-4 option tests to Kconfig kbuild: [bin]deb-pkg: add DPKG_FLAGS variable kbuild: move ".config not found!" message from Kconfig to Makefile kbuild: invoke syncconfig if include/config/auto.conf.cmd is missing kbuild: simplify single target rules kbuild: remove empty rules for makefiles kbuild: make -r/-R effective in top Makefile for old Make versions kbuild: move tools_silent to a more relevant place kbuild: compute false-positive -Wmaybe-uninitialized cases in Kconfig kbuild: refactor cc-cross-prefix implementation kbuild: hardcode genksyms path and remove GENKSYMS variable scripts/gdb: refactor rules for symlink creation kbuild: create symlink to vmlinux-gdb.py in scripts_gdb target scripts/gdb: do not descend into scripts/gdb from scripts ...
2019-03-07Merge tag 'trace-v5.0-pre' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fix/cleanup from Steven Rostedt: "This is a "pre-pull". It's only one small fix and one small clean up. I'm testing a few small patches for my real pull request which will come at a later time. The second patch depends on your tree anyway so I included it along with the urgent fix. A small fix Pavel sent me back in august was accidentally lost due to it being placed with some other patches that failed some tests, and was rebased out of my local tree. Which was a regression that caused event filters not to handle negative numbers. The clean up is from Masami that realized that the code in kprobes that calls probe_mem_read() wrapper, which is to be used in code used by both kprobes and uprobes, was only in code for kprobes. It should not use the wrapper there, but instead call probe_kernel_read() directly" * tag 'trace-v5.0-pre' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing/kprobes: Use probe_kernel_read instead of probe_mem_read tracing: Fix event filters and triggers to handle negative numbers
2019-03-05tracing: Use strncpy instead of memcpy when copying comm in trace.cTom Zanussi
Because there may be random garbage beyond a string's null terminator, code that might use the entire comm array e.g. histogram keys, can give unexpected results if that garbage is copied in too, so avoid that possibility by using strncpy instead of memcpy. Link: http://lkml.kernel.org/r/1d6ebac26570c2a29ce9fb575379f17ef5c8b81b.1551802084.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Suggested-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-05tracing: Use strncpy instead of memcpy when copying comm for hist triggersTom Zanussi
Because there may be random garbage beyond a string's null terminator, code that might use the entire comm array e.g. histogram keys, can give unexpected results if that garbage is copied in too, so avoid that possibility by using strncpy instead of memcpy. Link: http://lkml.kernel.org/r/1eb9f096a8086c3c82c7fc087c900005143cec54.1551802084.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>
2019-03-05tracing: Use strncpy instead of memcpy for string keys in hist triggersTom Zanussi
Because there may be random garbage beyond a string's null terminator, it's not correct to copy the the complete character array for use as a hist trigger key. This results in multiple histogram entries for the 'same' string key. So, in the case of a string key, use strncpy instead of memcpy to avoid copying in the extra bytes. Before, using the gdbus entries in the following hist trigger as an example: # echo 'hist:key=comm' > /sys/kernel/debug/tracing/events/sched/sched_waking/trigger # cat /sys/kernel/debug/tracing/events/sched/sched_waking/hist ... { comm: ImgDecoder #4 } hitcount: 203 { comm: gmain } hitcount: 213 { comm: gmain } hitcount: 216 { comm: StreamTrans #73 } hitcount: 221 { comm: mozStorage #3 } hitcount: 230 { comm: gdbus } hitcount: 233 { comm: StyleThread#5 } hitcount: 253 { comm: gdbus } hitcount: 256 { comm: gdbus } hitcount: 260 { comm: StyleThread#4 } hitcount: 271 ... # cat /sys/kernel/debug/tracing/events/sched/sched_waking/hist | egrep gdbus | wc -l 51 After: # cat /sys/kernel/debug/tracing/events/sched/sched_waking/hist | egrep gdbus | wc -l 1 Link: http://lkml.kernel.org/r/50c35ae1267d64eee975b8125e151e600071d4dc.1549309756.git.tom.zanussi@linux.intel.com Cc: Namhyung Kim <namhyung@kernel.org> Cc: stable@vger.kernel.org Fixes: 79e577cbce4c4 ("tracing: Support string type key properly") Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-05tracing: Use str_has_prefix() in synth_event_create()Tom Zanussi
Since we now have a str_has_prefix() that returns the length, we can use that instead of explicitly calculating it. Link: http://lkml.kernel.org/r/03418373fd1e80030e7394b8e3e081c5de28a710.1549309756.git.tom.zanussi@linux.intel.com Cc: Joe Perches <joe@perches.com> Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-01tracing/kprobes: Use probe_kernel_read instead of probe_mem_readMasami Hiramatsu
Use probe_kernel_read() instead of probe_mem_read() because probe_mem_read() is a kind of wrapper for switching memory read function between uprobes and kprobes. Link: http://lkml.kernel.org/r/20190222011643.3e19ade84a3db3e83518648f@kernel.org Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-03-01tracing: Fix event filters and triggers to handle negative numbersPavel Tikhomirov
Then tracing syscall exit event it is extremely useful to filter exit codes equal to some negative value, to react only to required errors. But negative numbers does not work: [root@snorch sys_exit_read]# echo "ret == -1" > filter bash: echo: write error: Invalid argument [root@snorch sys_exit_read]# cat filter ret == -1 ^ parse_error: Invalid value (did you forget quotes)? Similar thing happens when setting triggers. These is a regression in v4.17 introduced by the commit mentioned below, testing without these commit shows no problem with negative numbers. Link: http://lkml.kernel.org/r/20180823102534.7642-1-ptikhomirov@virtuozzo.com Cc: stable@vger.kernel.org Fixes: 80765597bc58 ("tracing: Rewrite filter logic to be simpler and faster") Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-28Merge branch 'linus' into perf/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-27kbuild: compute false-positive -Wmaybe-uninitialized cases in KconfigMasahiro Yamada
Since -Wmaybe-uninitialized was introduced by GCC 4.7, we have patched various false positives: - commit e74fc973b6e5 ("Turn off -Wmaybe-uninitialized when building with -Os") turned off this option for -Os. - commit 815eb71e7149 ("Kbuild: disable 'maybe-uninitialized' warning for CONFIG_PROFILE_ALL_BRANCHES") turned off this option for CONFIG_PROFILE_ALL_BRANCHES - commit a76bcf557ef4 ("Kbuild: enable -Wmaybe-uninitialized warning for "make W=1"") turned off this option for GCC < 4.9 Arnd provided more explanation in https://lkml.org/lkml/2017/3/14/903 I think this looks better by shifting the logic from Makefile to Kconfig. Link: https://github.com/ClangBuiltLinux/linux/issues/350 Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Tested-by: Nick Desaulniers <ndesaulniers@google.com>
2019-02-21tracing/perf: Use strndup_user() instead of buggy open-coded versionJann Horn
The first version of this method was missing the check for `ret == PATH_MAX`; then such a check was added, but it didn't call kfree() on error, so there was still a small memory leak in the error case. Fix it by using strndup_user() instead of open-coding it. Link: http://lkml.kernel.org/r/20190220165443.152385-1-jannh@google.com Cc: Ingo Molnar <mingo@kernel.org> Cc: stable@vger.kernel.org Fixes: 0eadcc7a7bc0 ("perf/core: Fix perf_uprobe_init()") Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-20tracing: Fix spelling mistake: "analagous" -> "analogous"Colin Ian King
There is a spelling mistake in the mini-howto help text. Fix it. Link: http://lkml.kernel.org/r/20190217223222.16479-1-colin.king@canonical.com Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-20tracing: Comment why cond_snapshot is checked outside of max_lock protectionSteven Rostedt (VMware)
Before setting tr->cond_snapshot, it must be NULL before it can be updated. It can go to NULL when a trace event hist trigger is created or removed, and can only be modified under the max_lock spin lock. But because it can only be set to something other than NULL under both the max_lock spin lock as well as the trace_types_lock, we can perform the check if it is not NULL only under the trace_types_lock and fail out without having to grab the max_lock spin lock. This is very subtle, and deserves a comment. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-20tracing: Add alternative synthetic event trace action syntaxTom Zanussi
Add a 'trace(synthetic_event_name, params)' alternative to synthetic_event_name(params). Currently, the syntax used for generating synthetic events is to invoke synthetic_event_name(params) i.e. use the synthetic event name as a function call. Users requested a new form that more explicitly shows that the synthetic event is in effect being traced. In this version, a new 'trace()' keyword is used, and the synthetic event name is passed in as the first argument. In addition, for the sake of consistency with other actions, change the documention to emphasize the trace() form over the function-call form, which remains documented as equivalent. Link: http://lkml.kernel.org/r/d082773e50232a001480cf837679a1e01c1a2eb7.1550100284.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>
2019-02-20tracing: Add hist trigger onchange() handlerTom Zanussi
Add support for a hist:onchange($var) handler, similar to the onmax() handler but triggering whenever there's any change in $var, not just a max. Link: http://lkml.kernel.org/r/dfbc7e4ada242603e9ec3f049b5ad076a07dfd03.1550100284.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-02-20tracing: Add hist trigger snapshot() actionTom Zanussi
Add support for hist:handlerXXX($var).snapshot(), which will take a snapshot of the current trace buffer whenever handlerXXX is hit. As a first user, this also adds snapshot() action support for the onmax() handler i.e. hist:onmax($var).snapshot(). Also, the hist trigger key printing is moved into a separate function so the snapshot() action can print a histogram key outside the histogram display - add and use hist_trigger_print_key() for that purpose. Link: http://lkml.kernel.org/r/2f1a952c0dcd8aca8702ce81269581a692396d45.1550100284.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>
2019-02-20tracing: Add conditional snapshotTom Zanussi
Currently, tracing snapshots are context-free - they capture the ring buffer contents at the time the tracing_snapshot() function was invoked, and nothing else. Additionally, they're always taken unconditionally - the calling code can decide whether or not to take a snapshot, but the data used to make that decision is kept separately from the snapshot itself. This change adds the ability to associate with each trace instance some user data, along with an 'update' function that can use that data to determine whether or not to actually take a snapshot. The update function can then update that data along with any other state (as part of the data presumably), if warranted. Because snapshots are 'global' per-instance, only one user can enable and use a conditional snapshot for any given trace instance. To enable a conditional snapshot (see details in the function and data structure comments), the user calls tracing_snapshot_cond_enable(). Similarly, to disable a conditional snapshot and free it up for other users, tracing_snapshot_cond_disable() should be called. To actually initiate a conditional snapshot, tracing_snapshot_cond() should be called. tracing_snapshot_cond() will invoke the update() callback, allowing the user to decide whether or not to actually take the snapshot and update the user-defined data associated with the snapshot. If the callback returns 'true', tracing_snapshot_cond() will then actually take the snapshot and return. This scheme allows for flexibility in snapshot implementations - for example, by implementing slightly different update() callbacks, snapshots can be taken in situations where the user is only interested in taking a snapshot when a new maximum in hit versus when a value changes in any way at all. Future patches will demonstrate both cases. Link: http://lkml.kernel.org/r/1bea07828d5fd6864a585f83b1eed47ce097eb45.1550100284.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>