[PATCH 21/22] arm: mm: drop ctor call for kernel page tables

From: Kevin Brodsky <kevin.brodsky@arm.com>
To: linux-mm@kvack.org
Cc: Kevin Brodsky <kevin.brodsky@arm.com>,
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Subject: [PATCH 21/22] arm: mm: drop ctor call for kernel page tables
Date: Tue, 14 Jul 2026 15:04:10 +0100	[thread overview]
Message-ID: <20260714-remove_pgtable_cdtor-v1-21-44be8a7685d7@arm.com> (raw)
In-Reply-To: <20260714-remove_pgtable_cdtor-v1-0-44be8a7685d7@arm.com>

Thanks to recent changes:

* pagetable_pte_ctor() does nothing for kernel page tables.

* efi_mm is also treated like a kernel mm by the page table logic,
  including ctors.

We can therefore drop the ctor call when allocating special kernel
page tables in mmu.c.

Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
---
 arch/arm/mm/mmu.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index 23b87b5ef7f1..c8de77a6f01e 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -728,8 +728,7 @@ static void *__init late_alloc(unsigned long sz)
 	void *ptdesc = pagetable_alloc(GFP_PGTABLE_KERNEL & ~__GFP_HIGHMEM,
 			get_order(sz));
 
-	if (!ptdesc || !pagetable_pte_ctor(NULL, ptdesc))
-		BUG();
+	BUG_ON(!ptdesc);
 	return ptdesc_address(ptdesc);
 }
 

-- 
2.51.2


