From 9a229ae249e0a24276901ad6807f31b32124f5c5 Mon Sep 17 00:00:00 2001
From: Finn Thain <fthain@linux-m68k.org>
Date: Tue, 13 Jan 2026 16:22:28 +1100
Subject: atomic: add option for weaker alignment check

Add a new Kconfig symbol to make CONFIG_DEBUG_ATOMIC more useful on those
architectures which do not align dynamic allocations to 8-byte boundaries.
Without this, CONFIG_DEBUG_ATOMIC produces excessive WARN splats.

Link: https://lkml.kernel.org/r/6d25a12934fe9199332f4d65d17c17de450139a8.1768281748.git.fthain@linux-m68k.org
Signed-off-by: Finn Thain <fthain@linux-m68k.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: "Borislav Petkov (AMD)" <bp@alien8.de>
Cc: Daniel Borkman <daniel@iogearbox.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Eduard Zingerman <eddyz87@gmail.com>
Cc: Gary Guo <gary@garyguo.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Hao Luo <haoluo@google.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Marc Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Sasha Levin (Microsoft) <sashal@kernel.org>
Cc: Song Liu <song@kernel.org>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Stanislav Fomichev <sdf@fomichev.me>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Cc: Yonghong Song <yonghong.song@linux.dev>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 lib/Kconfig.debug | 8 ++++++++
 1 file changed, 8 insertions(+)

(limited to 'lib')

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 9eb685d1ec44..7eed3b197ca9 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1370,6 +1370,14 @@ config DEBUG_ATOMIC
 
 	  This option has potentially significant overhead.
 
+config DEBUG_ATOMIC_LARGEST_ALIGN
+	bool "Check alignment only up to __aligned_largest"
+	depends on DEBUG_ATOMIC
+	help
+	  If you say Y here then the check for natural alignment of
+	  atomic accesses will be constrained to the compiler's largest
+	  alignment for scalar types.
+
 menu "Lock Debugging (spinlocks, mutexes, etc...)"
 
 config LOCK_DEBUGGING_SUPPORT
-- 
cgit v1.2.3