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From: Sang-Heon Jeon <ekffu200098@gmail.com>
To: Andrey Ryabinin <ryabinin.a.a@gmail.com>,
	Russell King <linux@armlinux.org.uk>
Cc: Sang-Heon Jeon <ekffu200098@gmail.com>,
	Alexander Potapenko <glider@google.com>,
	Andrey Konovalov <andreyknvl@gmail.com>,
	Dmitry Vyukov <dvyukov@google.com>,
	kasan-dev@googlegroups.com, linux-arm-kernel@lists.infradead.org,
	Vincenzo Frascino <vincenzo.frascino@arm.com>
Subject: [PATCH] ARM: remove unreachable invalid range check in kasan_init()
Date: Fri, 26 Jun 2026 03:40:36 +0900	[thread overview]
Message-ID: <20260625184037.630815-1-ekffu200098@gmail.com> (raw)

kasan_init() maps each memblock region with for_each_mem_range(), which
guarantees pa_start < pa_end. Then it skips any region with
pa_start >= arm_lowmem_limit, so pa_start < arm_lowmem_limit is guaranteed
as well.

When pa_end <= arm_lowmem_limit, pa_start < pa_end means start < end, so
the start >= end check is unreachable.

When pa_end > arm_lowmem_limit, end is clamped to __va(arm_lowmem_limit),
and pa_start < arm_lowmem_limit means start < end, so the check is
unreachable as well.

No functional change.

Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
---
 arch/arm/mm/kasan_init.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/arch/arm/mm/kasan_init.c b/arch/arm/mm/kasan_init.c
index c6625e808bf8..1f7c74c5df9e 100644
--- a/arch/arm/mm/kasan_init.c
+++ b/arch/arm/mm/kasan_init.c
@@ -262,12 +262,6 @@ void __init kasan_init(void)
 				&pa_start, &pa_end, &arm_lowmem_limit);
 			end = __va(arm_lowmem_limit);
 		}
-		if (start >= end) {
-			pr_info("Skipping invalid memory block %pa-%pa (virtual %p-%p)\n",
-				&pa_start, &pa_end, start, end);
-			continue;
-		}
-
 		create_mapping(start, end);
 	}
 
-- 
2.43.0



                 reply	other threads:[~2026-06-25 18:44 UTC|newest]

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