summaryrefslogtreecommitdiff
path: root/Documentation/admin-guide/dynamic-debug-howto.rst
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/admin-guide/dynamic-debug-howto.rst')
-rw-r--r--Documentation/admin-guide/dynamic-debug-howto.rst10
1 files changed, 8 insertions, 2 deletions
diff --git a/Documentation/admin-guide/dynamic-debug-howto.rst b/Documentation/admin-guide/dynamic-debug-howto.rst
index 0e9b48daf690..095a63892257 100644
--- a/Documentation/admin-guide/dynamic-debug-howto.rst
+++ b/Documentation/admin-guide/dynamic-debug-howto.rst
@@ -26,6 +26,11 @@ Dynamic debug provides:
- format string
- class name (as known/declared by each module)
+NOTE: To actually get the debug-print output on the console, you may
+need to adjust the kernel ``loglevel=``, or use ``ignore_loglevel``.
+Read about these kernel parameters in
+Documentation/admin-guide/kernel-parameters.rst.
+
Viewing Dynamic Debug Behaviour
===============================
@@ -218,12 +223,13 @@ The flags are::
f Include the function name
s Include the source file name
l Include line number
+ d Include call trace
For ``print_hex_dump_debug()`` and ``print_hex_dump_bytes()``, only
the ``p`` flag has meaning, other flags are ignored.
-Note the regexp ``^[-+=][fslmpt_]+$`` matches a flags specification.
-To clear all flags at once, use ``=_`` or ``-fslmpt``.
+Note the regexp ``^[-+=][fslmptd_]+$`` matches a flags specification.
+To clear all flags at once, use ``=_`` or ``-fslmptd``.
Debug messages during Boot Process