linux-kernel - [PATCH] vsprintf: avoid misleading "(null)" for %px

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Date:   Sun,  4 Feb 2018 18:45:21 +0100
From:   Adam Borowski <kilobyte@...band.pl>
To:     Petr Mladek <pmladek@...e.com>,
        Sergey Senozhatsky <sergey.senozhatsky@...il.com>,
        Steven Rostedt <rostedt@...dmis.org>,
        linux-kernel@...r.kernel.org
Cc:     Adam Borowski <kilobyte@...band.pl>
Subject: [PATCH] vsprintf: avoid misleading "(null)" for %px

Like %pK already does, print "00000000" instead.

This confused people -- the convention is that "(null)" means you tried to
dereference a null pointer as opposed to printing the address.

Signed-off-by: Adam Borowski <kilobyte@...band.pl>
---
 lib/vsprintf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 77ee6ced11b1..d7a708f82559 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -1849,7 +1849,7 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr,
 {
 	const int default_width = 2 * sizeof(void *);
 
-	if (!ptr && *fmt != 'K') {
+	if (!ptr && *fmt != 'K' && *fmt != 'x') {
 		/*
 		 * Print (null) with the same width as a pointer so it makes
 		 * tabular output look nice.
-- 
2.15.1