From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 635D0C433FE for ; Fri, 18 Nov 2022 05:31:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239454AbiKRFbP (ORCPT ); Fri, 18 Nov 2022 00:31:15 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52886 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230004AbiKRFbN (ORCPT ); Fri, 18 Nov 2022 00:31:13 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 6E81D87A49 for ; Thu, 17 Nov 2022 21:31:11 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 4595223A; Thu, 17 Nov 2022 21:31:17 -0800 (PST) Received: from a077893.blr.arm.com (unknown [10.162.41.7]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 0C5873F587; Thu, 17 Nov 2022 21:31:07 -0800 (PST) From: Anshuman Khandual To: linux-arm-kernel@lists.infradead.org Cc: Anshuman Khandual , Catalin Marinas , Will Deacon , Mark Rutland , Andrew Morton , linux-kernel@vger.kernel.org Subject: [PATCH] arm64/mm: Drop redundant BUG_ON(!pgtable_alloc) Date: Fri, 18 Nov 2022 11:01:02 +0530 Message-Id: <20221118053102.500216-1-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org __create_pgd_mapping_locked() expects a page allocator used while mapping a virtual range. This page allocator function propagates down the call chain, while building intermediate levels in the page table. Passed page allocator is a necessary ingredient required to build the page table but its presence can be asserted just once in the very beginning rather than in all the down stream functions. This consolidates BUG_ON(!pgtable_alloc) checks just in a single place i.e __create_pgd_mapping_locked(). Cc: Catalin Marinas Cc: Will Deacon Cc: Mark Rutland Cc: Andrew Morton Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual --- This applies on v6.1-rc5 arch/arm64/mm/mmu.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 5a19950e7289..97ca82001089 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -207,7 +207,6 @@ static void alloc_init_cont_pte(pmd_t *pmdp, unsigned long addr, if (flags & NO_EXEC_MAPPINGS) pmdval |= PMD_TABLE_PXN; - BUG_ON(!pgtable_alloc); pte_phys = pgtable_alloc(PAGE_SHIFT); __pmd_populate(pmdp, pte_phys, pmdval); pmd = READ_ONCE(*pmdp); @@ -285,7 +284,6 @@ static void alloc_init_cont_pmd(pud_t *pudp, unsigned long addr, if (flags & NO_EXEC_MAPPINGS) pudval |= PUD_TABLE_PXN; - BUG_ON(!pgtable_alloc); pmd_phys = pgtable_alloc(PMD_SHIFT); __pud_populate(pudp, pmd_phys, pudval); pud = READ_ONCE(*pudp); @@ -324,7 +322,6 @@ static void alloc_init_pud(pgd_t *pgdp, unsigned long addr, unsigned long end, if (flags & NO_EXEC_MAPPINGS) p4dval |= P4D_TABLE_PXN; - BUG_ON(!pgtable_alloc); pud_phys = pgtable_alloc(PUD_SHIFT); __p4d_populate(p4dp, pud_phys, p4dval); p4d = READ_ONCE(*p4dp); @@ -383,6 +380,7 @@ static void __create_pgd_mapping_locked(pgd_t *pgdir, phys_addr_t phys, phys &= PAGE_MASK; addr = virt & PAGE_MASK; end = PAGE_ALIGN(virt + size); + BUG_ON(!pgtable_alloc); do { next = pgd_addr_end(addr, end); -- 2.25.1