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 01DEF33EAEC; Mon, 18 Aug 2025 14:13:15 +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=1755526396; cv=none; b=RPI7Hx/r9PwUS7URlhYlwDurFEeCff7sXpwYZGy4k83Ch0GIn2fP9wu0W1nLztPjq62wVBecqE4T68s3WaF/Im9pv5h6Wu/22L+L2DtmhneJmZhqmWBSBMgWE+9ftbqZN7RlKX6iEb6HmTYmJj71OnUH63CbakUJIPUhBv95uUw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755526396; c=relaxed/simple; bh=pSLJ5Y1k/qSXfn6ar36UqJY+h7pK8CAkAROZb9PUAPc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=F0kInral48hzjkwky6QIe5nSiMMAfvdsoXZBvPI882LiXvbppToTcgnWXL7ghjTMHFL/33foU+RMW9NhlfDyvGoVkld6T26ljdeBAeaYKl73UBlbOmdrTGlE0N/jXkj89l8Uw++5U0uizCxZX+9KwnMpFF3QcnkFGE7CFy+wv10= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=MFGmlGo+; 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="MFGmlGo+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5A20FC4CEEB; Mon, 18 Aug 2025 14:13:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1755526395; bh=pSLJ5Y1k/qSXfn6ar36UqJY+h7pK8CAkAROZb9PUAPc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MFGmlGo+0YJ0cEsS5cseLGpzzaANSgt1TpN/ineTErWwo4mEDxI7w7KZO+YDPvQov F6hY0PLO9fk4qr08cUit8lvqKHhlATbHL3zv6sCaKX4rbxqmcfuNbHzWxUkDPjQgR9 1PiTgEQ6C5jZUISJDu3ClxEt5eriM55JlPsMAm+A= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, David Hildenbrand , Dan Williams , Lorenzo Stoakes , Jason Gunthorpe , Oscar Salvador , Alistair Popple , Baolin Wang , Dev Jain , Liam Howlett , Mariano Pache , Michal Hocko , Mike Rapoport , Ryan Roberts , Suren Baghdasaryan , Vlastimil Babka , Zi Yan , Andrew Morton Subject: [PATCH 6.16 543/570] mm/huge_memory: dont ignore queried cachemode in vmf_insert_pfn_pud() Date: Mon, 18 Aug 2025 14:48:50 +0200 Message-ID: <20250818124526.794145681@linuxfoundation.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250818124505.781598737@linuxfoundation.org> References: <20250818124505.781598737@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: David Hildenbrand commit 09fefdca80aebd1023e827cb0ee174983d829d18 upstream. Patch series "mm/huge_memory: vmf_insert_folio_*() and vmf_insert_pfn_pud() fixes", v3. While working on improving vm_normal_page() and friends, I stumbled over this issues: refcounted "normal" folios must not be marked using pmd_special() / pud_special(). Otherwise, we're effectively telling the system that these folios are no "normal", violating the rules we documented for vm_normal_page(). Fortunately, there are not many pmd_special()/pud_special() users yet. So far there doesn't seem to be serious damage. Tested using the ndctl tests ("ndctl:dax" suite). This patch (of 3): We set up the cache mode but ... don't forward the updated pgprot to insert_pfn_pud(). Only a problem on x86-64 PAT when mapping PFNs using PUDs that require a special cachemode. Fix it by using the proper pgprot where the cachemode was setup. It is unclear in which configurations we would get the cachemode wrong: through vfio seems possible. Getting cachemodes wrong is usually ... bad. As the fix is easy, let's backport it to stable. Identified by code inspection. Link: https://lkml.kernel.org/r/20250613092702.1943533-1-david@redhat.com Link: https://lkml.kernel.org/r/20250613092702.1943533-2-david@redhat.com Fixes: 7b806d229ef1 ("mm: remove vmf_insert_pfn_xxx_prot() for huge page-table entries") Signed-off-by: David Hildenbrand Reviewed-by: Dan Williams Reviewed-by: Lorenzo Stoakes Reviewed-by: Jason Gunthorpe Reviewed-by: Oscar Salvador Tested-by: Dan Williams Cc: Alistair Popple Cc: Baolin Wang Cc: Dev Jain Cc: Liam Howlett Cc: Mariano Pache Cc: Michal Hocko Cc: Mike Rapoport Cc: Ryan Roberts Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: Zi Yan Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- mm/huge_memory.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1516,10 +1516,9 @@ static pud_t maybe_pud_mkwrite(pud_t pud } static void insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr, - pud_t *pud, pfn_t pfn, bool write) + pud_t *pud, pfn_t pfn, pgprot_t prot, bool write) { struct mm_struct *mm = vma->vm_mm; - pgprot_t prot = vma->vm_page_prot; pud_t entry; if (!pud_none(*pud)) { @@ -1581,7 +1580,7 @@ vm_fault_t vmf_insert_pfn_pud(struct vm_ pfnmap_setup_cachemode_pfn(pfn_t_to_pfn(pfn), &pgprot); ptl = pud_lock(vma->vm_mm, vmf->pud); - insert_pfn_pud(vma, addr, vmf->pud, pfn, write); + insert_pfn_pud(vma, addr, vmf->pud, pfn, pgprot, write); spin_unlock(ptl); return VM_FAULT_NOPAGE; @@ -1625,7 +1624,7 @@ vm_fault_t vmf_insert_folio_pud(struct v add_mm_counter(mm, mm_counter_file(folio), HPAGE_PUD_NR); } insert_pfn_pud(vma, addr, vmf->pud, pfn_to_pfn_t(folio_pfn(folio)), - write); + vma->vm_page_prot, write); spin_unlock(ptl); return VM_FAULT_NOPAGE;