This patch initializes handle->options list in tracecmd_attach_cpu_data_fd().
When recorder sends trace data via network, server recording process is killed by SIGSEGV from the patch 71484a0854f7. This is because add_options() uses handle->options list from the patch, but tracecmd_attach_cpu_data_fd() calling add_options() does not initialize the list in spite of allocation of new handle. As the result, the server recording process will be killed because handle->options is cleared to zero in tracecmd_attach_cpu_data_fd(). <How to test> 1. Execute network(listen) server # trace-cmd listen -p 12345 2. Execute network client # trace-cmd record -e sched* -N <server IP>:12345 3. Stop the record on client ^C Here, network server should output a line "CPUX data recorded at offset=XXXX", but current network server aborts silently. Moreover the client's per-cpu files are separated. (Normally those files are merged into one trace file.) 4. Confirm error on network server # dmesg | tail -1 [18551.537113] trace-cmd[23073]: segfault at ffffffffffffffe8 ip 0000000000432fd1 sp 00007fffffa4caa0 error 5 in trace-cmd[400000+47000] After we would introduce this patch, the server will be fully able to output the client's tracing data and we will not get this error. Signed-off-by: Yoshihiro YUNOMAE <[email protected]> Cc: Steven Rostedt <[email protected]> --- trace-output.c | 1 + 1 file changed, 1 insertion(+) diff --git a/trace-output.c b/trace-output.c index ed81466..b033baa 100644 --- a/trace-output.c +++ b/trace-output.c @@ -1202,6 +1202,7 @@ int tracecmd_attach_cpu_data_fd(int fd, int cpus, char * const *cpu_data_files) handle->pevent = tracecmd_get_pevent(ihandle); pevent_ref(pevent); handle->page_size = tracecmd_page_size(ihandle); + list_head_init(&handle->options); if (tracecmd_append_cpu_data(handle, cpus, cpu_data_files) >= 0) ret = 0; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
