Add a WARN() macro; this is WARN_ON() + printk arguments

Add a WARN() macro that acts like WARN_ON(), with the added feature that it
takes a printk like argument that is printed as part of the warning message.

[akpm@linux-foundation.org: fix printk arguments]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Greg KH <greg@kroah.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 22 insertions, 0 deletions

diff --git a/kernel/panic.c b/kernel/panic.c
index 425567f45b9f..12c5a0a6c89b 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -318,6 +318,28 @@ void warn_on_slowpath(const char *file, int line)
         add_taint(TAINT_WARN);
 }
 EXPORT_SYMBOL(warn_on_slowpath);
+
+
+void warn_slowpath(const char *file, int line, const char *fmt, ...)
+{
+        va_list args;
+        char function[KSYM_SYMBOL_LEN];
+        unsigned long caller = (unsigned long)__builtin_return_address(0);
+        sprint_symbol(function, caller);
+
+        printk(KERN_WARNING "------------[ cut here ]------------\n");
+        printk(KERN_WARNING "WARNING: at %s:%d %s()\n", file,
+                line, function);
+        va_start(args, fmt);
+        vprintk(fmt, args);
+        va_end(args);
+
+        print_modules();
+        dump_stack();
+        print_oops_end_marker();
+        add_taint(TAINT_WARN);
+}
+EXPORT_SYMBOL(warn_slowpath);
 #endif
 
 #ifdef CONFIG_CC_STACKPROTECTOR