From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 664ED34BA42; Wed, 21 Jan 2026 18:35:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769020529; cv=none; b=Fx0k592QjX0D3/j0nC/mI7C+EqvGpb2eYh9+JE6uF+/V7YMR5SW2Uz6o3PeoN8HwQWYRC2uZSWIk6yXCc+bgLSlxVCyh5UynMamsCCtdqg/qgMwWG4Y8S967g/PU+MxWD9vbOOQBVj6QbkDdt2HnKmrKNbvi3LoYB7QQEJFxvFc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769020529; c=relaxed/simple; bh=ZRNL0YJcwZni7rjVYRZiaYIUSvhHQRsNrKXMvKIrw7U=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=llO6zlVbPXhsAOkia1RxABLbbgOCB5bKmaXXiEo8cRQIxUClM2tWOwYvrSqDuftfHRoyL6GYJTeQ5DFFVSMDme1nAYLJIx4Q1QV0ZE/x0BEEh7EwElTD1WEoKoTfhBMVhCfNpc+eQXCashmNxHCeL20RVxAAkFu2lCRpGckouFE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=M+WpB2Ed; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="M+WpB2Ed" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 99612C4CEF1; Wed, 21 Jan 2026 18:35:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1769020529; bh=ZRNL0YJcwZni7rjVYRZiaYIUSvhHQRsNrKXMvKIrw7U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=M+WpB2Ed6zB6O8CInMyoK0twgcVqL/RHxE02jveXTbpf3otOsSNqCIF4KqtkEnb+A FAKCuijxokitob/3PWIDEHq3RxZJJbJnWDsF7taOjMRxyFsU577OuiHTBodRgnUWhi vxDI5pVkFs5j4X6HfpELuiSsRtynZzBP/tYaOQ9o= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dave Hansen , Lu Baolu , Jason Gunthorpe , Kevin Tian , Alistair Popple , Andy Lutomirski , Borislav Betkov , David Hildenbrand , Ingo Molnar , Jann Horn , Jean-Philippe Brucker , Joerg Roedel , Liam Howlett , Lorenzo Stoakes , "Matthew Wilcox (Oracle)" , Michal Hocko , "Mike Rapoport (Microsoft)" , Peter Zijlstra , Robin Murohy , Thomas Gleinxer , "Uladzislau Rezki (Sony)" , Vasant Hegde , Vinicius Costa Gomes , Vlastimil Babka , Will Deacon , Yi Lai , Andrew Morton Subject: [PATCH 6.18 186/198] x86/mm: use ptdesc when freeing PMD pages Date: Wed, 21 Jan 2026 19:16:54 +0100 Message-ID: <20260121181425.247229651@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260121181418.537774329@linuxfoundation.org> References: <20260121181418.537774329@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dave Hansen commit 412d000346ea38ac4b9bb715a86c73ef89d90dea upstream. There are a billion ways to refer to a physical memory address. One of the x86 PMD freeing code location chooses to use a 'pte_t *' to point to a PMD page and then call a PTE-specific freeing function for it. That's a bit wonky. Just use a 'struct ptdesc *' instead. Its entire purpose is to refer to page table pages. It also means being able to remove an explicit cast. Right now, pte_free_kernel() is a one-liner that calls pagetable_dtor_free(). Effectively, all this patch does is remove one superfluous __pa(__va(paddr)) conversion and then call pagetable_dtor_free() directly instead of through a helper. Link: https://lkml.kernel.org/r/20251022082635.2462433-5-baolu.lu@linux.intel.com Signed-off-by: Dave Hansen Signed-off-by: Lu Baolu Reviewed-by: Jason Gunthorpe Reviewed-by: Kevin Tian Cc: Alistair Popple Cc: Andy Lutomirski Cc: Borislav Betkov Cc: David Hildenbrand Cc: Ingo Molnar Cc: Jann Horn Cc: Jean-Philippe Brucker Cc: Joerg Roedel Cc: Liam Howlett Cc: Lorenzo Stoakes Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Mike Rapoport (Microsoft) Cc: Peter Zijlstra Cc: Robin Murohy Cc: Thomas Gleinxer Cc: "Uladzislau Rezki (Sony)" Cc: Vasant Hegde Cc: Vinicius Costa Gomes Cc: Vlastimil Babka Cc: Will Deacon Cc: Yi Lai Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- arch/x86/mm/pgtable.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -729,7 +729,7 @@ int pmd_clear_huge(pmd_t *pmd) int pud_free_pmd_page(pud_t *pud, unsigned long addr) { pmd_t *pmd, *pmd_sv; - pte_t *pte; + struct ptdesc *pt; int i; pmd = pud_pgtable(*pud); @@ -750,8 +750,8 @@ int pud_free_pmd_page(pud_t *pud, unsign for (i = 0; i < PTRS_PER_PMD; i++) { if (!pmd_none(pmd_sv[i])) { - pte = (pte_t *)pmd_page_vaddr(pmd_sv[i]); - pte_free_kernel(&init_mm, pte); + pt = page_ptdesc(pmd_page(pmd_sv[i])); + pagetable_dtor_free(pt); } } @@ -772,15 +772,15 @@ int pud_free_pmd_page(pud_t *pud, unsign */ int pmd_free_pte_page(pmd_t *pmd, unsigned long addr) { - pte_t *pte; + struct ptdesc *pt; - pte = (pte_t *)pmd_page_vaddr(*pmd); + pt = page_ptdesc(pmd_page(*pmd)); pmd_clear(pmd); /* INVLPG to clear all paging-structure caches */ flush_tlb_kernel_range(addr, addr + PAGE_SIZE-1); - pte_free_kernel(&init_mm, pte); + pagetable_dtor_free(pt); return 1; }