Patch "minmax.h: use BUILD_BUG_ON_MSG() for the lo < hi test in clamp()" has been added to the 6.1-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    minmax.h: use BUILD_BUG_ON_MSG() for the lo < hi test in clamp()

to the 6.1-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     minmax.h-use-build_bug_on_msg-for-the-lo-hi-test-in-clamp.patch
and it can be found in the queue-6.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


From stable+bounces-183179-greg=kroah.com@vger.kernel.org Fri Oct  3 14:27:07 2025
From: Eliav Farber <farbere@amazon.com>
Date: Fri, 3 Oct 2025 12:15:17 +0000
Subject: minmax.h: use BUILD_BUG_ON_MSG() for the lo < hi test in clamp()
To: <gregkh@linuxfoundation.org>, <kenneth.feng@amd.com>, <alexander.deucher@amd.com>, <christian.koenig@amd.com>, <airlied@gmail.com>, <simona@ffwll.ch>, <linus.walleij@linaro.org>, <dmitry.torokhov@gmail.com>, <tglx@linutronix.de>, <wens@csie.org>, <jernej.skrabec@gmail.com>, <samuel@sholland.org>, <agk@redhat.com>, <snitzer@kernel.org>, <mpatocka@redhat.com>, <clm@fb.com>, <dsterba@suse.com>, <luc.vanoostenryck@gmail.com>, <pmladek@suse.com>, <rostedt@goodmis.org>, <andriy.shevchenko@linux.intel.com>, <linux@rasmusvillemoes.dk>, <senozhatsky@chromium.org>, <akpm@linux-foundation.org>, <lijo.lazar@amd.com>, <asad.kamal@amd.com>, <kevinyang.wang@amd.com>, <David.Laight@ACULAB.COM>, <amd-gfx@lists.freedesktop.org>, <dri-devel@lists.freedesktop.org>, <linux-kernel@vger.kernel.org>, <linux-input@vger.kernel.org>, <linux-arm-kernel@lists.infradead.org>, <linux-sunxi@lists.linux.dev>, <dm-devel@lists.linux.dev>, <linux-btrfs@vger.kernel.org>, <linux-sparse@vger.kernel.org>, <stable@vger.
 kernel.org>, <farbere@amazon.com>
Cc: Arnd Bergmann <arnd@kernel.org>, Christoph Hellwig <hch@infradead.org>, Dan Carpenter <dan.carpenter@linaro.org>, "Jason A. Donenfeld" <Jason@zx2c4.com>, Jens Axboe <axboe@kernel.dk>, Lorenzo Stoakes <lorenzo.stoakes@oracle.com>, Mateusz Guzik <mjguzik@gmail.com>, "Matthew Wilcox" <willy@infradead.org>, Pedro Falcato <pedro.falcato@gmail.com>
Message-ID: <20251003121520.8176-9-farbere@amazon.com>

From: David Laight <David.Laight@ACULAB.COM>

[ Upstream commit a5743f32baec4728711bbc01d6ac2b33d4c67040 ]

Use BUILD_BUG_ON_MSG(statically_true(ulo > uhi), ...) for the sanity check
of the bounds in clamp().  Gives better error coverage and one less
expansion of the arguments.

Link: https://lkml.kernel.org/r/34d53778977747f19cce2abb287bb3e6@AcuMS.aculab.com
Signed-off-by: David Laight <david.laight@aculab.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Arnd Bergmann <arnd@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Dan Carpenter <dan.carpenter@linaro.org>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Pedro Falcato <pedro.falcato@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Eliav Farber <farbere@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 include/linux/minmax.h |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

--- a/include/linux/minmax.h
+++ b/include/linux/minmax.h
@@ -106,8 +106,7 @@
 	__auto_type uval = (val);						\
 	__auto_type ulo = (lo);							\
 	__auto_type uhi = (hi);							\
-	static_assert(__builtin_choose_expr(__is_constexpr((lo) > (hi)), 	\
-			(lo) <= (hi), true),					\
+	BUILD_BUG_ON_MSG(statically_true(ulo > uhi),				\
 		"clamp() low limit " #lo " greater than high limit " #hi);	\
 	BUILD_BUG_ON_MSG(!__types_ok3(uval, ulo, uhi),				\
 		"clamp("#val", "#lo", "#hi") signedness error");		\


Patches currently in stable-queue which might be from farbere@amazon.com are

queue-6.1/minmax-improve-macro-expansion-and-type-checking.patch
queue-6.1/minmax.h-simplify-the-variants-of-clamp.patch
queue-6.1/minmax.h-move-all-the-clamp-definitions-after-the-min-max-ones.patch
queue-6.1/minmax-don-t-use-max-in-situations-that-want-a-c-constant-expression.patch
queue-6.1/minmax.h-remove-some-defines-that-are-only-expanded-once.patch
queue-6.1/minmax.h-use-build_bug_on_msg-for-the-lo-hi-test-in-clamp.patch
queue-6.1/minmax-simplify-min-max-clamp-implementation.patch
queue-6.1/minmax.h-add-whitespace-around-operators-and-after-commas.patch
queue-6.1/minmax-fix-up-min3-and-max3-too.patch
queue-6.1/minmax.h-reduce-the-define-expansion-of-min-max-and-clamp.patch
queue-6.1/minmax.h-update-some-comments.patch