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 2844B3D75C9; Wed, 8 Apr 2026 18:48:43 +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=1775674123; cv=none; b=Wz1QiJ/pQe1aoe475BqpRyTG0AblvuXK5VT1CzFzJIraKVq7XPhDasvXpcDKe9fFWJkTSEoGaoEeJV1Weavq9ACLo65895mq75azbgLl97fJMM5gnkzGe/sfshB0p75tMhV7aNYwFF/7a3kOXVlmix3GAcAWGVjARJ/pynzCECw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775674123; c=relaxed/simple; bh=4dr1lm8gzXOr3VI16dSs13mT6z55E07qIqOXCteOwJs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=EsfakyCYKqxhgpt3lUJ+zW6g3sfgVfnYU8u5/pFP8xyZdhyfy5T+e+GSXYV8/PcGvc3tgxtCNSUozdQ/1R4T+SNmXA7eNXEuVTuI/THp+e9EF8StqZfSUeLEecQ8f+M8yIakqGppe5mm9HoEd++D0KW+mzFLWwvgBQPyRf1SSio= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=OKrRqd3U; 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="OKrRqd3U" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A8064C19421; Wed, 8 Apr 2026 18:48:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1775674123; bh=4dr1lm8gzXOr3VI16dSs13mT6z55E07qIqOXCteOwJs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OKrRqd3UDeZjIoyIpSoEPU5Mm/N+R63+26J6mVW6rSga8Tmp6AECCeZvwFt6QBAfO a/6wWEriamknMpVbstuh+YMewFA80Wgb+4N5JcG/DZOl84BfYGRNY5SgGgAC8DIt71 RywqQl10L+MvYEW45cm5TiDIhPokwccnotqI2ilU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Anshuman Khandual , David Hildenbrand , Lance Yang , Wei Yang , Dev Jain , Andrew Morton , Sasha Levin Subject: [PATCH 6.12 219/242] mm: replace READ_ONCE() with standard page table accessors Date: Wed, 8 Apr 2026 20:04:19 +0200 Message-ID: <20260408175935.282337893@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260408175927.064985309@linuxfoundation.org> References: <20260408175927.064985309@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 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Anshuman Khandual [ Upstream commit c0efdb373c3aaacb32db59cadb0710cac13e44ae ] Replace all READ_ONCE() with a standard page table accessors i.e pxdp_get() that defaults into READ_ONCE() in cases where platform does not override. Link: https://lkml.kernel.org/r/20251007063100.2396936-1-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual Acked-by: David Hildenbrand Reviewed-by: Lance Yang Reviewed-by: Wei Yang Reviewed-by: Dev Jain Signed-off-by: Andrew Morton Stable-dep-of: ffef67b93aa3 ("mm/memory: fix PMD/PUD checks in follow_pfnmap_start()") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- mm/gup.c | 10 +++++----- mm/hmm.c | 2 +- mm/memory.c | 4 ++-- mm/mprotect.c | 2 +- mm/sparse-vmemmap.c | 2 +- mm/vmscan.c | 2 +- 6 files changed, 11 insertions(+), 11 deletions(-) --- a/mm/gup.c +++ b/mm/gup.c @@ -1013,7 +1013,7 @@ static struct page *follow_pud_mask(stru struct mm_struct *mm = vma->vm_mm; pudp = pud_offset(p4dp, address); - pud = READ_ONCE(*pudp); + pud = pudp_get(pudp); if (!pud_present(pud)) return no_page_table(vma, flags, address); if (pud_leaf(pud)) { @@ -1038,7 +1038,7 @@ static struct page *follow_p4d_mask(stru p4d_t *p4dp, p4d; p4dp = p4d_offset(pgdp, address); - p4d = READ_ONCE(*p4dp); + p4d = p4dp_get(p4dp); BUILD_BUG_ON(p4d_leaf(p4d)); if (!p4d_present(p4d) || p4d_bad(p4d)) @@ -3301,7 +3301,7 @@ static int gup_fast_pud_range(p4d_t *p4d pudp = pud_offset_lockless(p4dp, p4d, addr); do { - pud_t pud = READ_ONCE(*pudp); + pud_t pud = pudp_get(pudp); next = pud_addr_end(addr, end); if (unlikely(!pud_present(pud))) @@ -3327,7 +3327,7 @@ static int gup_fast_p4d_range(pgd_t *pgd p4dp = p4d_offset_lockless(pgdp, pgd, addr); do { - p4d_t p4d = READ_ONCE(*p4dp); + p4d_t p4d = p4dp_get(p4dp); next = p4d_addr_end(addr, end); if (!p4d_present(p4d)) @@ -3349,7 +3349,7 @@ static void gup_fast_pgd_range(unsigned pgdp = pgd_offset(current->mm, addr); do { - pgd_t pgd = READ_ONCE(*pgdp); + pgd_t pgd = pgdp_get(pgdp); next = pgd_addr_end(addr, end); if (pgd_none(pgd)) --- a/mm/hmm.c +++ b/mm/hmm.c @@ -423,7 +423,7 @@ static int hmm_vma_walk_pud(pud_t *pudp, /* Normally we don't want to split the huge page */ walk->action = ACTION_CONTINUE; - pud = READ_ONCE(*pudp); + pud = pudp_get(pudp); if (!pud_present(pud)) { spin_unlock(ptl); return hmm_vma_walk_hole(start, end, -1, walk); --- a/mm/memory.c +++ b/mm/memory.c @@ -6451,12 +6451,12 @@ retry: goto out; p4dp = p4d_offset(pgdp, address); - p4d = READ_ONCE(*p4dp); + p4d = p4dp_get(p4dp); if (p4d_none(p4d) || unlikely(p4d_bad(p4d))) goto out; pudp = pud_offset(p4dp, address); - pud = READ_ONCE(*pudp); + pud = pudp_get(pudp); if (pud_none(pud)) goto out; if (pud_leaf(pud)) { --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -447,7 +447,7 @@ again: break; } - pud = READ_ONCE(*pudp); + pud = pudp_get(pudp); if (pud_none(pud)) continue; --- a/mm/sparse-vmemmap.c +++ b/mm/sparse-vmemmap.c @@ -337,7 +337,7 @@ int __meminit vmemmap_populate_hugepages return -ENOMEM; pmd = pmd_offset(pud, addr); - if (pmd_none(READ_ONCE(*pmd))) { + if (pmd_none(pmdp_get(pmd))) { void *p; p = vmemmap_alloc_block_buf(PMD_SIZE, node, altmap); --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -3631,7 +3631,7 @@ static int walk_pud_range(p4d_t *p4d, un pud = pud_offset(p4d, start & P4D_MASK); restart: for (i = pud_index(start), addr = start; addr != end; i++, addr = next) { - pud_t val = READ_ONCE(pud[i]); + pud_t val = pudp_get(pud + i); next = pud_addr_end(addr, end);