From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 7AFCA48380B; Wed, 2 Sep 2026 11:57:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788350289; cv=none; b=dIePLE7WwMmrpf4Yn6DepQK7WSbohn3t6FBdb9Okup98w4ATlcM++BeDf79ZVairn6Uf9+zG04j9CQMNVBg6hbs/uguXcbPajeBINwQGoHlRcSMVj2R3GqIy3ro5qNQhFBfDsj7z7Bj54csp1fBRpw2EVNPbU3q4wxGfByA9RQg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788350289; c=relaxed/simple; bh=u1Z77HcuVhsn6YhXUmkFsPEbxxF45OV6fwB+pGKvXaw=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=EMflEw+9FLbgjgpnEgAno6nJ4CvYtMxg3deEeygEKpraeySlEKYMAc6k7DOa65d5Zb8N4aDhdjXLMJJ0sQ6vBYIbAPIaYQk1GiL4o0lbxS9oBgMZ8hvF7vxaCZ5fcuWjyTJsNLHgGwUYkdG1w8UAvftYLS/Q+kjfzQziMq3QAqI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=KwVckYUF; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="KwVckYUF" 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 569A31E32; Wed, 2 Sep 2026 04:57:47 -0700 (PDT) Received: from e129823.arm.com (e129823.arm.com [10.2.213.3]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D20183F85F; Wed, 2 Sep 2026 04:57:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1788350271; bh=u1Z77HcuVhsn6YhXUmkFsPEbxxF45OV6fwB+pGKvXaw=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=KwVckYUFD0lh0ySdrjYJ96Swie3hj5sqm3vMY81r3S03FnG0fxHPzd0qowq8aZG5g IKesnnrhaDKSBya7uksmJfX5kn32Lpqri7nZkx6IJdyAEy0gh9YyZGvb8St62p+VF+ jHU2x45mp/UblfZisQApAggIrhQmd+H9mASJWRUg= From: Yeoreum Yun Date: Wed, 02 Sep 2026 12:56:12 +0100 Subject: [PATCH RFC v3 10/21] riscv: kvm: remove stack copy address of pXd in pXd_offset() Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260902-dummy_ptxp3-v3-10-5d8f5b17c25c@arm.com> References: <20260902-dummy_ptxp3-v3-0-5d8f5b17c25c@arm.com> In-Reply-To: <20260902-dummy_ptxp3-v3-0-5d8f5b17c25c@arm.com> To: Russell King , Huacai Chen , WANG Xuerui , Thomas Bogendoerfer , Catalin Marinas , Will Deacon , Arnd Bergmann , Andrew Morton , Kairui Song , Qi Zheng , Shakeel Butt , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Johannes Weiner , David Hildenbrand , Michal Hocko , Lorenzo Stoakes , Tianrui Zhao , Bibo Mao , Anup Patel , Atish Patra , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Dave Hansen , Andy Lutomirski , Peter Zijlstra , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H. Peter Anvin" , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jonas Bonn , Stefan Kristiansson , Stafford Horne Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-openrisc@vger.kernel.org, Yeoreum Yun X-Mailer: b4 0.13.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2078; i=yeoreum.yun@arm.com; h=from:subject:message-id; bh=u1Z77HcuVhsn6YhXUmkFsPEbxxF45OV6fwB+pGKvXaw=; b=owEB7QES/pANAwAKAW3Vw9FaxTEzAcsmYgBqmA7mT8hWwbLEAfZ37PxMdkX2SXibeCCh04uq4 LVfmdutif2JAbMEAAEKAB0WIQQtg+CS3QUzuFh1pJ1t1cPRWsUxMwUCapgO5gAKCRBt1cPRWsUx M+PqC/40X13zsXs8BTi8kV5papAGh8OSIhs97QZRguA2644nXsxQL0KWVabFVdCiD01eIXjwiwK xc28n/yQ0VytaKVRoLdH2uaCikWav9oZ9XDLjMzQLSF1EWLel4YSmV+pQdtzVzQsSoi9YTysn3x JkUT86wqAghgrmHxTDoQ6TjpqsBNziVpG+FIHDJt0oyS1A5b6+50SiwZpCxoJktIFfQqctIE67X pOpT704P02sdCZmz5tnhqEEANwjL1IDJy5g7ax557FSOnEeb1fqbAiC5aA32WSWn00wvg29OODg QEENRDtdwmzRDVlc6E6KtCngcNjmmnYj3BBEb6ma3mwUfahX0QMDHlGAEFkBKP7JbWcXpjz6UMh O7HhjVbbW6duC29hFpC0g4D0iBai5cCFlp4WKlyC5tzjeOm6WUg2qQJObDgIEGd6t/v+1NGFPg+ 7gtTrSnpWjJSAYpwvyDrtlfK3hO9M/URw/sMGNUnH2v1a6efUQCi9kCBVlEsxT7nPtlCo= X-Developer-Key: i=yeoreum.yun@arm.com; a=openpgp; fpr=2D83E092DD0533B85875A49D6DD5C3D15AC53133 The behaviour of pXdp_get() will change with generic compile-time folded page tables. To prepare for that, rework get_hva_mapping_size() to avoid use of a stack copy of a pXd and pass it as argument to pXd_offset() so that the folded entries value is ignored. Replace direct uses of stack-based pXd values with pXd_offset_lockless() and there should be no functional change. Reviewed-by: David Hildenbrand (Arm) Signed-off-by: Yeoreum Yun --- arch/riscv/kvm/mmu.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c index 6035b5ec9503..dd5a7b0bd084 100644 --- a/arch/riscv/kvm/mmu.c +++ b/arch/riscv/kvm/mmu.c @@ -450,10 +450,10 @@ static int get_hva_mapping_size(struct kvm *kvm, { int size = PAGE_SIZE; unsigned long flags; - pgd_t pgd; - p4d_t p4d; - pud_t pud; - pmd_t pmd; + pgd_t *pgdp, pgd; + p4d_t *p4dp, p4d; + pud_t *pudp, pud; + pmd_t *pmdp, pmd; /* * Disable IRQs to prevent concurrent tear down of host page tables, @@ -469,15 +469,18 @@ static int get_hva_mapping_size(struct kvm *kvm, * value) and then p*d_offset() walks into the target huge page instead * of the old page table (sees the new value). */ - pgd = pgdp_get(pgd_offset(kvm->mm, hva)); + pgdp = pgd_offset(kvm->mm, hva); + pgd = pgdp_get(pgdp); if (pgd_none(pgd)) goto out; - p4d = p4dp_get(p4d_offset(&pgd, hva)); + p4dp = p4d_offset_lockless(pgdp, pgd, hva); + p4d = p4dp_get(p4dp); if (p4d_none(p4d) || !p4d_present(p4d)) goto out; - pud = pudp_get(pud_offset(&p4d, hva)); + pudp = pud_offset_lockless(p4dp, p4d, hva); + pud = pudp_get(pudp); if (pud_none(pud) || !pud_present(pud)) goto out; @@ -486,7 +489,8 @@ static int get_hva_mapping_size(struct kvm *kvm, goto out; } - pmd = pmdp_get(pmd_offset(&pud, hva)); + pmdp = pmd_offset_lockless(pudp, pud, hva); + pmd = pmdp_get(pmdp); if (pmd_none(pmd) || !pmd_present(pmd)) goto out; -- 2.43.0