This is a note to let you know that I've just added the patch titled tracing: Have tracing_snapshot_instance_cond() write errors to the appropriate instance to the 6.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: tracing-have-tracing_snapshot_instance_cond-write-er.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 7956504631f26c0095dcbcf778b2b9fff45712cd Author: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx> Date: Tue Apr 4 22:21:14 2023 -0400 tracing: Have tracing_snapshot_instance_cond() write errors to the appropriate instance [ Upstream commit 9d52727f8043cfda241ae96896628d92fa9c50bb ] If a trace instance has a failure with its snapshot code, the error message is to be written to that instance's buffer. But currently, the message is written to the top level buffer. Worse yet, it may also disable the top level buffer and not the instance that had the issue. Link: https://lkml.kernel.org/r/20230405022341.688730321@xxxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Ross Zwisler <zwisler@xxxxxxxxxx> Fixes: 2824f50332486 ("tracing: Make the snapshot trigger work with instances") Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 5016ae826c463..3360d638071a1 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1112,22 +1112,22 @@ static void tracing_snapshot_instance_cond(struct trace_array *tr, unsigned long flags; if (in_nmi()) { - internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); - internal_trace_puts("*** snapshot is being ignored ***\n"); + trace_array_puts(tr, "*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); + trace_array_puts(tr, "*** snapshot is being ignored ***\n"); return; } if (!tr->allocated_snapshot) { - internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); - internal_trace_puts("*** stopping trace here! ***\n"); - tracing_off(); + trace_array_puts(tr, "*** SNAPSHOT NOT ALLOCATED ***\n"); + trace_array_puts(tr, "*** stopping trace here! ***\n"); + tracer_tracing_off(tr); return; } /* Note, snapshot can not be used when the tracer uses it */ if (tracer->use_max_tr) { - internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); - internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); + trace_array_puts(tr, "*** LATENCY TRACER ACTIVE ***\n"); + trace_array_puts(tr, "*** Can not use snapshot (sorry) ***\n"); return; }