On Thu, 25 Jan 2024 17:16:21 -0300 "Ricardo B. Marliere" <[email protected]> wrote:
> Now that trace_seq_reset have been created, correct the places where the > buffers need to be initialized. This patch would need to come first. You don't ever want to intentionally create a broken kernel. Also, the change log should be: In order to extend trace_seq into being dynamic, the struct trace_seq will no longer be valid if simply set to zero. Call trace_seq_init() for all trace_seq when they are first created. > > Suggested-by: Steven Rostedt <[email protected]> > Signed-off-by: Ricardo B. Marliere <[email protected]> > --- > kernel/trace/trace.c | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > You also need to initialize iter.seq in ftrace_dump() -- Steve > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > index d4c55d3e21c2..9827700d0164 100644 > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -4889,6 +4889,9 @@ __tracing_open(struct inode *inode, struct file *file, > bool snapshot) > > mutex_unlock(&trace_types_lock); > > + trace_seq_init(&iter->seq); > + trace_seq_init(&iter->tmp_seq); > + > return iter; > > fail: > @@ -6770,6 +6773,7 @@ static int tracing_open_pipe(struct inode *inode, > struct file *filp) > } > > trace_seq_init(&iter->seq); > + trace_seq_init(&iter->tmp_seq); > iter->trace = tr->current_trace; > > if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { > @@ -6947,6 +6951,7 @@ tracing_read_pipe(struct file *filp, char __user *ubuf, > trace_iterator_reset(iter); > cpumask_clear(iter->started); > trace_seq_init(&iter->seq); > + trace_seq_init(&iter->tmp_seq); > > trace_event_read_lock(); > trace_access_lock(iter->cpu_file); > @@ -8277,6 +8282,9 @@ static int tracing_buffers_open(struct inode *inode, > struct file *filp) > if (ret < 0) > trace_array_put(tr); > > + trace_seq_init(&info->iter.seq); > + trace_seq_init(&info->iter.tmp_seq); > + > return ret; > } > > @@ -10300,6 +10308,9 @@ void trace_init_global_iter(struct trace_iterator > *iter) > iter->temp_size = STATIC_TEMP_BUF_SIZE; > iter->fmt = static_fmt_buf; > iter->fmt_size = STATIC_FMT_BUF_SIZE; > + > + trace_seq_init(&iter->seq); > + trace_seq_init(&iter->tmp_seq); > } > > void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) > @@ -10712,6 +10723,9 @@ void __init early_trace_init(void) > tracepoint_printk = 0; > else > static_key_enable(&tracepoint_printk_key.key); > + > + trace_seq_init(&tracepoint_print_iter->seq); > + trace_seq_init(&tracepoint_print_iter->tmp_seq); > } > tracer_alloc_buffers(); >
