summaryrefslogtreecommitdiff
path: root/Documentation/printk-formats.txt
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2015-11-07 22:32:45 (GMT)
committerLinus Torvalds <torvalds@linux-foundation.org>2015-11-07 22:32:45 (GMT)
commitad804a0b2a769a0eed29015c53fe395449c09d13 (patch)
tree3f96dd15fe24705cd8244bdb8fb81a7195f6ea04 /Documentation/printk-formats.txt
parentab9f2faf8f40604551336e5b0a18e0910a57b92c (diff)
parent5f2a2d5d423d5337a1392fa016ec23a8a4206006 (diff)
downloadlinux-ad804a0b2a769a0eed29015c53fe395449c09d13.tar.xz
Merge branch 'akpm' (patches from Andrew)
Merge second patch-bomb from Andrew Morton: - most of the rest of MM - procfs - lib/ updates - printk updates - bitops infrastructure tweaks - checkpatch updates - nilfs2 update - signals - various other misc bits: coredump, seqfile, kexec, pidns, zlib, ipc, dma-debug, dma-mapping, ... * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (102 commits) ipc,msg: drop dst nil validation in copy_msg include/linux/zutil.h: fix usage example of zlib_adler32() panic: release stale console lock to always get the logbuf printed out dma-debug: check nents in dma_sync_sg* dma-mapping: tidy up dma_parms default handling pidns: fix set/getpriority and ioprio_set/get in PRIO_USER mode kexec: use file name as the output message prefix fs, seqfile: always allow oom killer seq_file: reuse string_escape_str() fs/seq_file: use seq_* helpers in seq_hex_dump() coredump: change zap_threads() and zap_process() to use for_each_thread() coredump: ensure all coredumping tasks have SIGNAL_GROUP_COREDUMP signal: remove jffs2_garbage_collect_thread()->allow_signal(SIGCONT) signal: introduce kernel_signal_stop() to fix jffs2_garbage_collect_thread() signal: turn dequeue_signal_lock() into kernel_dequeue_signal() signals: kill block_all_signals() and unblock_all_signals() nilfs2: fix gcc uninitialized-variable warnings in powerpc build nilfs2: fix gcc unused-but-set-variable warnings MAINTAINERS: nilfs2: add header file for tracing nilfs2: add tracepoints for analyzing reading and writing metadata files ...
Diffstat (limited to 'Documentation/printk-formats.txt')
-rw-r--r--Documentation/printk-formats.txt29
1 files changed, 29 insertions, 0 deletions
diff --git a/Documentation/printk-formats.txt b/Documentation/printk-formats.txt
index 2216eb1..b784c27 100644
--- a/Documentation/printk-formats.txt
+++ b/Documentation/printk-formats.txt
@@ -23,6 +23,10 @@ Example:
Reminder: sizeof() result is of type size_t.
+The kernel's printf does not support %n. For obvious reasons, floating
+point formats (%e, %f, %g, %a) are also not recognized. Use of any
+unsupported specifier or length qualifier results in a WARN and early
+return from vsnprintf.
Raw pointer value SHOULD be printed with %p. The kernel supports
the following extended format specifiers for pointer types:
@@ -119,6 +123,7 @@ Raw buffer as an escaped string:
If field width is omitted the 1 byte only will be escaped.
Raw buffer as a hex string:
+
%*ph 00 01 02 ... 3f
%*phC 00:01:02: ... :3f
%*phD 00-01-02- ... -3f
@@ -234,6 +239,7 @@ UUID/GUID addresses:
Passed by reference.
dentry names:
+
%pd{,2,3,4}
%pD{,2,3,4}
@@ -256,6 +262,8 @@ struct va_format:
va_list *va;
};
+ Implements a "recursive vsnprintf".
+
Do not use this feature without some mechanism to verify the
correctness of the format string and va_list arguments.
@@ -284,6 +292,27 @@ bitmap and its derivatives such as cpumask and nodemask:
Passed by reference.
+Network device features:
+
+ %pNF 0x000000000000c000
+
+ For printing netdev_features_t.
+
+ Passed by reference.
+
+Command from struct task_struct
+
+ %pT ls
+
+ For printing executable name excluding path from struct
+ task_struct.
+
+ Passed by reference.
+
+If you add other %p extensions, please extend lib/test_printf.c with
+one or more test cases, if at all feasible.
+
+
Thank you for your cooperation and attention.