+ bug-shut-up-format-attribute-warning-for-clang-as-well.patch added to mm-hotfixes-unstable branch

+ bug-shut-up-format-attribute-warning-for-clang-as-well.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: lib/bug.c: shut up format attribute warning for clang as well
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     bug-shut-up-format-attribute-warning-for-clang-as-well.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/bug-shut-up-format-attribute-warning-for-clang-as-well.patch

This patch will later appear in the mm-hotfixes-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Arnd Bergmann <arnd@arndb.de>
Subject: lib/bug.c: shut up format attribute warning for clang as well
Date: Fri, 20 Mar 2026 22:14:25 +0100

Like gcc, clang-22 now also warns about a function that it
incorrectly identifies as a printf-style format:

lib/bug.c:190:22: error: diagnostic behavior may be improved by adding the 'format(printf, 1, 0)' attribute to the declaration of '__warn_printf' [-Werror,-Wmissing-format-attribute]
  179 | static void __warn_printf(const char *fmt, struct pt_regs *regs)
      | __attribute__((format(printf, 1, 0)))
  180 | {
  181 |         if (!fmt)
  182 |                 return;
  183 |
  184 | #ifdef HAVE_ARCH_BUG_FORMAT_ARGS
  185 |         if (regs) {
  186 |                 struct arch_va_list _args;
  187 |                 va_list *args = __warn_args(&_args, regs);
  188 |
  189 |                 if (args) {
  190 |                         vprintk(fmt, *args);
      |                                           ^

Turn off this warning for all compilers and versions.

Link: https://lkml.kernel.org/r/20260320211528.2474389-1-arnd@kernel.org
Fixes: d36067d6ea00 ("bug: Hush suggest-attribute=format for __warn_printf()")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Bill Wendling <morbo@google.com>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Justin Stitt <justinstitt@google.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 lib/bug.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

--- a/lib/bug.c~bug-shut-up-format-attribute-warning-for-clang-as-well
+++ a/lib/bug.c
@@ -174,8 +174,7 @@ struct bug_entry *find_bug(unsigned long
 }
 
 __diag_push();
-__diag_ignore(GCC, all, "-Wsuggest-attribute=format",
-	      "Not a valid __printf() conversion candidate.");
+__diag_ignore_all("-Wmissing-format-attribute", "Not a valid __printf() conversion candidate.");
 static void __warn_printf(const char *fmt, struct pt_regs *regs)
 {
 	if (!fmt)
_

Patches currently in -mm which might be from arnd@arndb.de are

bug-shut-up-format-attribute-warning-for-clang-as-well.patch
ubsan-turn-off-kmsan-inside-of-ubsan-instrumentation.patch
mm-vmscan-avoid-false-positive-wuninitialized-warning.patch