From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 593072DC792 for ; Wed, 16 Sep 2026 14:47:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789570029; cv=none; b=p7WLH7yMKLdhfDA5QfMidLNhJ1CBYaL3LGg/p2KVsxTogWQB8FhkJlvJ59He0C53+wN1NR0A5x/SmEu7n1NBRkuP6+ussT2QWi+04MP8GxP39fr9R6I5S+gK58BTo2JnBhShT11/RoDLUKNipYIV2HlE8dABhDz3drWIrD4d86c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789570029; c=relaxed/simple; bh=ZyEgeqrmj/4VPpxeZQ8HanuvLx83KqmUKGlFYw610XU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=MfkSvYqMXrHdVCFIZe5nb14khuyNVg0ua/iurYaAvKItp+yC6/o9hnyrqLumdmP0qDRwpYMewu5ENv6tMdmfwNBgnVinr1cefuxnW+lnxFqqxz6Hw1hyPdcEiGoqTF0i+ixtyRflrDW6Jqfclf9n4wcPPWF1Dg4auY1DbkbgHBs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=E+HDR9Xo; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="E+HDR9Xo" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 577F51F000FF; Wed, 16 Sep 2026 14:47:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789570027; bh=Z2rQ1L7Sb25HTZUvitDHbpcMKj8TuSQcOS0QQcKde74=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=E+HDR9XoFv+Z0Oct42oeB8Vef8SL94+fQkTsdj9qptiWvb3gSjnFAViacaxt+GcKq FjPaCYLucgQThchEAv4wYk81TUZXsHX1OhoGJWx0Z+uLBHXFYaW9tgcRsbRYygMMnW H164nmk/pDR+Duup16G98jjcDHxsoUyMzR1S6DdJ7tPIjbU1//R73fZRdndSdQI1Vg MmOcAEgVnu3yH4o32LkG9UM1Fi/H0FqLNNdv2m86GfRkqfbNrAsS/Z5dXa3Y7q8Rzs 0EMXwja6slrPf0l+NVnFosDe8ebJlbtDTtWT82pTGd3iTpITrytQMNKs0Ioud+6zW+ Qc18aSN/EOmYw== From: Sasha Levin To: stable@vger.kernel.org Cc: "Vishal Moola (Oracle)" , Dave Hansen , "Mike Rapoport (Microsoft)" , Sasha Levin Subject: [PATCH 6.18.y 1/3] x86/mm/pat: Convert split_large_page() to use ptdescs Date: Wed, 16 Sep 2026 10:47:03 -0400 Message-ID: <20260916144705.3627256-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026091615-lankiness-vowed-5e5d@gregkh> References: <2026091615-lankiness-vowed-5e5d@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: "Vishal Moola (Oracle)" [ Upstream commit e751303e0ad2e998f421d104193f6904df3516d1 ] Use the ptdesc APIs for all page table allocation and free sites to allow their separate allocation from struct page in the future. Update split_large_page() to allocate a ptdesc instead of allocating a page for use as a page table. Signed-off-by: Vishal Moola (Oracle) Signed-off-by: Dave Hansen Acked-by: Mike Rapoport (Microsoft) Link: https://patch.msgid.link/20260303194828.1406905-5-vishal.moola@gmail.com Stable-dep-of: d5d8b8662e6e ("x86/mm/pat: Acquire init_mm read lock on attribute changes to avoid UAF") Signed-off-by: Sasha Levin --- arch/x86/mm/pat/set_memory.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c index de74be2e69bf7..3621532fccb61 100644 --- a/arch/x86/mm/pat/set_memory.c +++ b/arch/x86/mm/pat/set_memory.c @@ -1125,9 +1125,10 @@ static void split_set_pte(struct cpa_data *cpa, pte_t *pte, unsigned long pfn, static int __split_large_page(struct cpa_data *cpa, pte_t *kpte, unsigned long address, - struct page *base) + struct ptdesc *ptdesc) { unsigned long lpaddr, lpinc, ref_pfn, pfn, pfninc = 1; + struct page *base = ptdesc_page(ptdesc); pte_t *pbase = (pte_t *)page_address(base); unsigned int i, level; pgprot_t ref_prot; @@ -1232,18 +1233,18 @@ __split_large_page(struct cpa_data *cpa, pte_t *kpte, unsigned long address, static int split_large_page(struct cpa_data *cpa, pte_t *kpte, unsigned long address) { - struct page *base; + struct ptdesc *ptdesc; if (!debug_pagealloc_enabled()) spin_unlock(&cpa_lock); - base = alloc_pages(GFP_KERNEL, 0); + ptdesc = pagetable_alloc(GFP_KERNEL, 0); if (!debug_pagealloc_enabled()) spin_lock(&cpa_lock); - if (!base) + if (!ptdesc) return -ENOMEM; - if (__split_large_page(cpa, kpte, address, base)) - __free_page(base); + if (__split_large_page(cpa, kpte, address, ptdesc)) + pagetable_free(ptdesc); return 0; } -- 2.53.0