From 6c95503c292610ff2898b4271c510c16efdcd4e1 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Sat, 20 Jun 2020 12:45:54 +0900 Subject: tracing/boot: Fix config dependency for synthedic event Since commit 726721a51838 ("tracing: Move synthetic events to a separate file") decoupled synthetic event from histogram, boot-time tracing also has to check CONFIG_SYNTH_EVENT instead of CONFIG_HIST_TRIGGERS. Link: http://lkml.kernel.org/r/159262475441.185015.5300725180746017555.stgit@devnote2 Fixes: 726721a51838 ("tracing: Move synthetic events to a separate file") Reviewed-by: Tom Zanussi Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_boot.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/trace/trace_boot.c') diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c index 9de29bb45a27..8b5490cb02bb 100644 --- a/kernel/trace/trace_boot.c +++ b/kernel/trace/trace_boot.c @@ -120,7 +120,7 @@ trace_boot_add_kprobe_event(struct xbc_node *node, const char *event) } #endif -#ifdef CONFIG_HIST_TRIGGERS +#ifdef CONFIG_SYNTH_EVENTS static int __init trace_boot_add_synth_event(struct xbc_node *node, const char *event) { -- cgit v1.2.3 From 20dc3847cc2fc886ee4eb9112e6e2fad9419b0c7 Mon Sep 17 00:00:00 2001 From: Sascha Ortmann Date: Thu, 18 Jun 2020 18:33:01 +0200 Subject: tracing/boottime: Fix kprobe multiple events Fix boottime kprobe events to report and abort after each failure when adding probes. As an example, when we try to set multiprobe kprobe events in bootconfig like this: ftrace.event.kprobes.vfsevents { probes = "vfs_read $arg1 $arg2,, !error! not reported;?", // leads to error "vfs_write $arg1 $arg2" } This will not work as expected. After commit da0f1f4167e3af69e ("tracing/boottime: Fix kprobe event API usage"), the function trace_boot_add_kprobe_event will not produce any error message when adding a probe fails at kprobe_event_gen_cmd_start. Furthermore, we continue to add probes when kprobe_event_gen_cmd_end fails (and kprobe_event_gen_cmd_start did not fail). In this case the function even returns successfully when the last call to kprobe_event_gen_cmd_end is successful. The behaviour of reporting and aborting after failures is not consistent. The function trace_boot_add_kprobe_event now reports each failure and stops adding probes immediately. Link: https://lkml.kernel.org/r/20200618163301.25854-1-sascha.ortmann@stud.uni-hannover.de Cc: stable@vger.kernel.org Cc: linux-kernel@i4.cs.fau.de Co-developed-by: Maximilian Werner Fixes: da0f1f4167e3 ("tracing/boottime: Fix kprobe event API usage") Acked-by: Masami Hiramatsu Signed-off-by: Maximilian Werner Signed-off-by: Sascha Ortmann Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_boot.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'kernel/trace/trace_boot.c') diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c index 8b5490cb02bb..fa0fc08c6ef8 100644 --- a/kernel/trace/trace_boot.c +++ b/kernel/trace/trace_boot.c @@ -101,12 +101,16 @@ trace_boot_add_kprobe_event(struct xbc_node *node, const char *event) kprobe_event_cmd_init(&cmd, buf, MAX_BUF_LEN); ret = kprobe_event_gen_cmd_start(&cmd, event, val); - if (ret) + if (ret) { + pr_err("Failed to generate probe: %s\n", buf); break; + } ret = kprobe_event_gen_cmd_end(&cmd); - if (ret) + if (ret) { pr_err("Failed to add probe: %s\n", buf); + break; + } } return ret; -- cgit v1.2.3