[1] and [2] introduced a new gid mount options that could apply to a
group to all entries in tracefs.

Document this in the tracing readme.

[1] https://lore.kernel.org/r/[email protected]/T/#u
[2] https://lore.kernel.org/r/[email protected]/T/#u

Cc: David Howells <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Masami Hiramatsu <[email protected]>
Signed-off-by: Kalesh Singh <[email protected]>
---
 kernel/trace/trace.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index a8f52b6527ca..2b64b3ec67d9 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -5501,6 +5501,10 @@ static const struct file_operations tracing_iter_fops = {
 
 static const char readme_msg[] =
        "tracing mini-HOWTO:\n\n"
+       "By default tracefs removes all OTH file permission bits.\n"
+       "When mounting tracefs an optional group id can be specified\n"
+       "which adds the group to every directory and file in tracefs:\n\n"
+       "\t e.g. mount -t tracefs [-o [gid=<gid>]] nodev 
/sys/kernel/tracing\n\n"
        "# echo 0 > tracing_on : quick way to disable tracing\n"
        "# echo 1 > tracing_on : quick way to re-enable tracing\n\n"
        " Important files:\n"
-- 
2.47.0.163.g1226f6d8fa-goog


Reply via email to