linux-kernel - [PATCH v2 5/5] mm: simplify variadic args handling

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-Id: <20251201-va_format_call-v2-5-2906f3093b60@intel.com>
Date: Mon, 01 Dec 2025 10:31:26 +0100
From: Andrzej Hajda <andrzej.hajda@...el.com>
To: Petr Mladek <pmladek@...e.com>, Steven Rostedt <rostedt@...dmis.org>, 
 John Ogness <john.ogness@...utronix.de>, 
 Sergey Senozhatsky <senozhatsky@...omium.org>, 
 Greg Kroah-Hartman <gregkh@...uxfoundation.org>, 
 "Rafael J. Wysocki" <rafael@...nel.org>, Danilo Krummrich <dakr@...nel.org>, 
 Andrew Morton <akpm@...ux-foundation.org>, Vlastimil Babka <vbabka@...e.cz>, 
 Suren Baghdasaryan <surenb@...gle.com>, Michal Hocko <mhocko@...e.com>, 
 Brendan Jackman <jackmanb@...gle.com>, Johannes Weiner <hannes@...xchg.org>, 
 Zi Yan <ziy@...dia.com>, Christoph Lameter <cl@...two.org>, 
 David Rientjes <rientjes@...gle.com>, 
 Roman Gushchin <roman.gushchin@...ux.dev>, Harry Yoo <harry.yoo@...cle.com>
Cc: linux-kernel@...r.kernel.org, linux-mm@...ck.org, 
 Andrzej Hajda <andrzej.hajda@...el.com>
Subject: [PATCH v2 5/5] mm: simplify variadic args handling

Changing argument type from va_list to struct va_format * allows
to simplify variadic argument handling with va_format_call helper.

Signed-off-by: Andrzej Hajda <andrzej.hajda@...el.com>
---
 mm/slub.c | 23 ++++-------------------
 1 file changed, 4 insertions(+), 19 deletions(-)

diff --git a/mm/slub.c b/mm/slub.c
index 786c5a4195d4..12d8ec97eac5 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1135,27 +1135,16 @@ void skip_orig_size_check(struct kmem_cache *s, const void *object)
 	set_orig_size(s, (void *)object, s->object_size);
 }

-static void __slab_bug(struct kmem_cache *s, const char *fmt, va_list argsp)
+static void __slab_bug(struct kmem_cache *s, const char *fmt, struct va_format *vaf)
 {
-	struct va_format vaf;
-	va_list args;
-
-	va_copy(args, argsp);
-	vaf.fmt = fmt;
-	vaf.va = &args;
 	pr_err("=============================================================================\n");
-	pr_err("BUG %s (%s): %pV\n", s ? s->name : "<unknown>", print_tainted(), &vaf);
+	pr_err("BUG %s (%s): %pV\n", s ? s->name : "<unknown>", print_tainted(), vaf);
 	pr_err("-----------------------------------------------------------------------------\n\n");
-	va_end(args);
 }

 static void slab_bug(struct kmem_cache *s, const char *fmt, ...)
 {
-	va_list args;
-
-	va_start(args, fmt);
-	__slab_bug(s, fmt, args);
-	va_end(args);
+	va_format_call(fmt, __slab_bug, s, fmt, va_format_arg);
 }

 __printf(2, 3)
@@ -1252,14 +1241,10 @@ static void __slab_err(struct slab *slab)
 static __printf(3, 4) void slab_err(struct kmem_cache *s, struct slab *slab,
 			const char *fmt, ...)
 {
-	va_list args;
-
 	if (slab_add_kunit_errors())
 		return;

-	va_start(args, fmt);
-	__slab_bug(s, fmt, args);
-	va_end(args);
+	va_format_call(fmt, __slab_bug, s, fmt, va_format_arg);

 	__slab_err(slab);
 }

-- 
2.43.0