From ab1561f23867c4a538c4aeaa11b7d01bd678eeaf Mon Sep 17 00:00:00 2001
From: Randy Dunlap <randy.dunlap@oracle.com>
Date: Wed, 12 Nov 2008 13:26:55 -0800
Subject: [PATCH] --- yaml --- r: 118911 b: refs/heads/master c:
 b67ad18b06701b77ca8bfe9bb760c5c9e765e3cf h: refs/heads/master i:   118909:
 1fa86a2753ed50393b4e28f43dd1866cef2c698e   118907:
 e65e00423abe6d55bb384691b84484ba0b4d4e79   118903:
 404bb1ec2c9f1a231b1cb8fdcbdfb95096080a01   118895:
 b6f8e0ecf3aa769c7ce8a5dd69bdf3fead3e89a5   118879:
 1bbc577a862b5a38b8358b1ac991671d90c97ae8   118847:
 c09381f54c05105b6b94b2ccc665006ff203b1cd   118783:
 e9cfd9d0e9c7c1ce7a6051b7a72d180d1d5e5070 v: v3

---
 [refs]                                 |  2 +-
 trunk/Documentation/00-INDEX           |  2 ++
 trunk/Documentation/printk-formats.txt | 35 ++++++++++++++++++++++++++
 3 files changed, 38 insertions(+), 1 deletion(-)
 create mode 100644 trunk/Documentation/printk-formats.txt

diff --git a/[refs] b/[refs]
index 5fe49c4df88e..239c300b18a9 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: b76f90b526737070302a127c710263e2ac707676
+refs/heads/master: b67ad18b06701b77ca8bfe9bb760c5c9e765e3cf
diff --git a/trunk/Documentation/00-INDEX b/trunk/Documentation/00-INDEX
index edef85ce1195..50f99eab0e1f 100644
--- a/trunk/Documentation/00-INDEX
+++ b/trunk/Documentation/00-INDEX
@@ -290,6 +290,8 @@ powerpc/
 	- directory with info on using Linux with the PowerPC.
 preempt-locking.txt
 	- info on locking under a preemptive kernel.
+printk-formats.txt
+	- how to get printk format specifiers right
 prio_tree.txt
 	- info on radix-priority-search-tree use for indexing vmas.
 ramdisk.txt
diff --git a/trunk/Documentation/printk-formats.txt b/trunk/Documentation/printk-formats.txt
new file mode 100644
index 000000000000..1b5a5ddbc3ef
--- /dev/null
+++ b/trunk/Documentation/printk-formats.txt
@@ -0,0 +1,35 @@
+If variable is of Type,		use printk format specifier:
+---------------------------------------------------------
+		int			%d or %x
+		unsigned int		%u or %x
+		long			%ld or %lx
+		unsigned long		%lu or %lx
+		long long		%lld or %llx
+		unsigned long long	%llu or %llx
+		size_t			%zu or %zx
+		ssize_t			%zd or %zx
+
+Raw pointer value SHOULD be printed with %p.
+
+u64 SHOULD be printed with %llu/%llx, (unsigned long long):
+
+	printk("%llu", (unsigned long long)u64_var);
+
+s64 SHOULD be printed with %lld/%llx, (long long):
+
+	printk("%lld", (long long)s64_var);
+
+If <type> is dependent on a config option for its size (e.g., sector_t,
+blkcnt_t, phys_addr_t, resource_size_t) or is architecture-dependent
+for its size (e.g., tcflag_t), use a format specifier of its largest
+possible type and explicitly cast to it.  Example:
+
+	printk("test: sector number/total blocks: %llu/%llu\n",
+		(unsigned long long)sector, (unsigned long long)blockcount);
+
+Reminder: sizeof() result is of type size_t.
+
+Thank you for your cooperation and attention.
+
+
+By Randy Dunlap <rdunlap@xenotime.net>