manpage: Document probe provider compatibility

Fixes #502

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/doc/man/lttng-ust.3 b/doc/man/lttng-ust.3
index 7cc3bfde5b7112b354d6d5c4e81fc4c0115d45dc..4e30d7622c37e950e3c482141872b7e805ec63d9 100644 (file)
--- a/doc/man/lttng-ust.3
+++ b/doc/man/lttng-ust.3
@@ -362,10 +362,23 @@ startup time.
 .PP
 lttng-gen-tp(1), lttng(1), babeltrace(1), lttng-sessiond(8)
 .PP
+
+.SH "COMPATIBILITY"
+
+.PP
+Older lttng-ust libraries reject more recent, and incompatible, probe
+providers. Newer lttng-ust librairies accept older probe providers, even
+though some newer features might not be available with those providers.
+.PP
+
 .SH "BUGS"
 
 .PP
-No knows bugs at this point.
+LTTng-UST 2.0 and 2.1 lttng-ust libraries do not check for probe
+provider version compatibility. This can lead to out-of-bound accesses
+when using a more recent probe provider with an older lttng-ust library.
+These error only trigger when tracing is active. This issue has been
+fixed in LTTng-UST 2.2.
 
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