kasan_init() maps each memblock region with for_each_mem_range() and passes
it to kasan_init_phys_region(), which does nothing when start >= end.
for_each_mem_range() never returns an invalid range, so start < end always.

Therefore the start >= end check is unreachable, so remove it.

No functional change.

Signed-off-by: Sang-Heon Jeon <redacted>
---
This patch is similar to my earlier series [1] that removed unreachable invalid
range checks in memblock iteration loops. I just missed it at the time.

[1] https://lore.kernel.org/all/20260621145919.1453-1-ekffu200098@gmail.com/ (local)
---

 arch/powerpc/mm/kasan/init_book3e_64.c | 3 ---
 arch/powerpc/mm/kasan/init_book3s_64.c | 3 ---
 2 files changed, 6 deletions(-)

diff --git a/arch/powerpc/mm/kasan/init_book3e_64.c b/arch/powerpc/mm/kasan/init_book3e_64.c
index 0d3a73d6d4b0..0ed372fb8b09 100644
--- a/arch/powerpc/mm/kasan/init_book3e_64.c
+++ b/arch/powerpc/mm/kasan/init_book3e_64.c

@@ -68,9 +68,6 @@ static void __init kasan_init_phys_region(void *start, void *end)
 	unsigned long k_start, k_end, k_cur;
 	void *va;
 
-	if (start >= end)
-		return;
-
 	k_start = ALIGN_DOWN((unsigned long)kasan_mem_to_shadow(start), PAGE_SIZE);
 	k_end = ALIGN((unsigned long)kasan_mem_to_shadow(end), PAGE_SIZE);
 

diff --git a/arch/powerpc/mm/kasan/init_book3s_64.c b/arch/powerpc/mm/kasan/init_book3s_64.c
index dcafa641804c..ccfbfb894637 100644
--- a/arch/powerpc/mm/kasan/init_book3s_64.c
+++ b/arch/powerpc/mm/kasan/init_book3s_64.c

@@ -24,9 +24,6 @@ static void __init kasan_init_phys_region(void *start, void *end)
 	unsigned long k_start, k_end, k_cur;
 	void *va;
 
-	if (start >= end)
-		return;
-
 	k_start = ALIGN_DOWN((unsigned long)kasan_mem_to_shadow(start), PAGE_SIZE);
 	k_end = ALIGN((unsigned long)kasan_mem_to_shadow(end), PAGE_SIZE);
 

-- 
2.43.0