From nobody Mon Feb 9 06:34:46 2026 Received: from mail-pl1-f201.google.com (mail-pl1-f201.google.com [209.85.214.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DABE836A606 for ; Tue, 28 Oct 2025 22:58:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761692337; cv=none; b=U6wYEBd0n5n0IwUcwJa6RW1ILVNeEgCiW6uzQbhRsxaZqgmKQz6PnD6GKIiq3ocvwrEa1Nh6kgDLOp7Urpe9R777vTk3zdesl0NAXCGr5VCGE+zoaYFmHwbLxALm6ui028KuPuFrp8xhUaqmASR4xiN/IASfVt/jp3zn5c+ZV+0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761692337; c=relaxed/simple; bh=9LfQM2hIUlxZZG/asJrlAoGIB42sfh2arlqfx9NqS1s=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Content-Type; b=PnyNuuo/R+bCeEVYZkED02lezms7zjKrXZ6UFhWXewbbEq6QjOzhgDh7HnabP/3tPPofFMbzcDZtbeMxpHPEdMBSi8oF/jq46e3vvm9IOPhL7TILqPCEzoP3ne3BlR3jWq282ofLsP7ThQFRP96q2UVPyZEqyGgK+BChYPaQwcI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--jmattson.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=Gi4jsgAl; arc=none smtp.client-ip=209.85.214.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--jmattson.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Gi4jsgAl" Received: by mail-pl1-f201.google.com with SMTP id d9443c01a7336-26983c4d708so49624725ad.3 for ; Tue, 28 Oct 2025 15:58:55 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1761692335; x=1762297135; darn=vger.kernel.org; h=to:from:subject:message-id:references:mime-version:in-reply-to:date :from:to:cc:subject:date:message-id:reply-to; bh=LsN+TIOejwkRxcFvSTLIziuR7qVC+NSwlbaa713vCGw=; b=Gi4jsgAl6gOVkt9ckb0Tpv47WFDv0jLavDbPetB/+v0sG2bhtZFpe1WI/M/WmmW7WC f4FkKhiBdhUn8zbSXlC93pS4hQ7lXg9ZlD8WDP0eYY+MdbRo0JOgQ/2tScHAoSI6l7ZE 2xnINzE+JpAH/oE/l7qUPuzmiZe3ptERHe0wMmqmrdzgaAupueUu41kMx6GtppEJUjiH krNp4eynWEijmX+elrszyXel+KEOia8AEdNI+qzfgKL856cnobtRrgjtLRuXz/GJtt6u HEIfhyQNl6bkEtTxPGxFUgR2tVGFYh2eKZiJuTbnepwV5BWr5Y61B/v+OicPGDjVt9T9 fCSA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1761692335; x=1762297135; h=to:from:subject:message-id:references:mime-version:in-reply-to:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=LsN+TIOejwkRxcFvSTLIziuR7qVC+NSwlbaa713vCGw=; b=wgS1yg4qc/ISytlY4qM3fD/wr8QXLPjSk0W3rmoPPu/hgf6dQquKiBbv8JOCyNZrwh nnP5+8XRvuvYwPUYuORz/IfwnjkYvCjGJspyxukLkWBSQxxMSBaF7XjABz1Qgi0RlGri +iVUig7F452mXGKppc0YffldRROia/j4P78lLbhGmfOXEPGydtMOS5G+2pbUq258GA69 YS4kkzElRWYxrlhbU51zIz1a6jpe8vrBYBqfFfMoLy5w02xVvyWZERFWoiSk/zQOaLqa Z6Lmdv19K1b5KK+bBH0HiSwusnZZOAd0c8npar2rYedK9hd7MpZRXqD9/kKBBKtnyznn 8Fag== X-Forwarded-Encrypted: i=1; AJvYcCVV/5GgQpLcwzDFaSGfoS4HWG8x8PlOeveONfUcNEUI0wYBor0y0r5c0gsZRD/bjrAFVYUEJiX8KePblWY=@vger.kernel.org X-Gm-Message-State: AOJu0Yy2P5r1nD7Ojajp96JsPcHK3NKhk5zjw4RlzUeahUnou3tfwyQm snMKZpsWWElk+YS2n0PeEKm9mpN4ROFNQNgf8Aoq4f88mHpO97eypwJny2r2OFR2peeC8ghws1w bkU0tXoxuZnDAEQ== X-Google-Smtp-Source: AGHT+IEMVSuG9lR7nieExZvnnc5AQBFrpxM2bdWmWvBi3SSEzKa00dcCH/wBtXjIXiNue0RQB/h1x65fEm/mgQ== X-Received: from pjvv11.prod.google.com ([2002:a17:90b:588b:b0:33e:3612:2208]) (user=jmattson job=prod-delivery.src-stubby-dispatcher) by 2002:a17:903:2a86:b0:290:dd1f:3d60 with SMTP id d9443c01a7336-294def5a88amr8429735ad.51.1761692335281; Tue, 28 Oct 2025 15:58:55 -0700 (PDT) Date: Tue, 28 Oct 2025 15:30:40 -0700 In-Reply-To: <20251028225827.2269128-1-jmattson@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20251028225827.2269128-1-jmattson@google.com> X-Mailer: git-send-email 2.51.1.851.g4ebd6896fd-goog Message-ID: <20251028225827.2269128-3-jmattson@google.com> Subject: [PATCH v2 2/4] KVM: selftests: Use a loop to walk guest page tables From: Jim Mattson To: Paolo Bonzini , Shuah Khan , Sean Christopherson , Marc Zyngier , Oliver Upton , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Andrew Jones , Huacai Chen , Bibo Mao , Jim Mattson , "Pratik R. Sampat" , James Houghton , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Walk the guest page tables via a loop when searching for a PTE, instead of using unique variables for each level of the page tables. This simplifies the code and makes it easier to support 5-level paging in the future. Signed-off-by: Jim Mattson Reviewed-by: Yosry Ahmed --- .../testing/selftests/kvm/lib/x86/processor.c | 23 ++++++++----------- 1 file changed, 10 insertions(+), 13 deletions(-) diff --git a/tools/testing/selftests/kvm/lib/x86/processor.c b/tools/testin= g/selftests/kvm/lib/x86/processor.c index 738f2a44083f..720c678187b5 100644 --- a/tools/testing/selftests/kvm/lib/x86/processor.c +++ b/tools/testing/selftests/kvm/lib/x86/processor.c @@ -307,7 +307,8 @@ static bool vm_is_target_pte(uint64_t *pte, int *level,= int current_level) uint64_t *__vm_get_page_table_entry(struct kvm_vm *vm, uint64_t vaddr, int *level) { - uint64_t *pml4e, *pdpe, *pde; + uint64_t *pte =3D &vm->pgd; + int current_level; =20 TEST_ASSERT(!vm->arch.is_pt_protected, "Walking page tables of protected guests is impossible"); @@ -328,19 +329,15 @@ uint64_t *__vm_get_page_table_entry(struct kvm_vm *vm= , uint64_t vaddr, TEST_ASSERT(vaddr =3D=3D (((int64_t)vaddr << 16) >> 16), "Canonical check failed. The virtual address is invalid."); =20 - pml4e =3D virt_get_pte(vm, &vm->pgd, vaddr, PG_LEVEL_512G); - if (vm_is_target_pte(pml4e, level, PG_LEVEL_512G)) - return pml4e; - - pdpe =3D virt_get_pte(vm, pml4e, vaddr, PG_LEVEL_1G); - if (vm_is_target_pte(pdpe, level, PG_LEVEL_1G)) - return pdpe; - - pde =3D virt_get_pte(vm, pdpe, vaddr, PG_LEVEL_2M); - if (vm_is_target_pte(pde, level, PG_LEVEL_2M)) - return pde; + for (current_level =3D vm->pgtable_levels; + current_level > PG_LEVEL_4K; + current_level--) { + pte =3D virt_get_pte(vm, pte, vaddr, current_level); + if (vm_is_target_pte(pte, level, current_level)) + return pte; + } =20 - return virt_get_pte(vm, pde, vaddr, PG_LEVEL_4K); + return virt_get_pte(vm, pte, vaddr, PG_LEVEL_4K); } =20 uint64_t *vm_get_page_table_entry(struct kvm_vm *vm, uint64_t vaddr) --=20 2.51.1.851.g4ebd6896fd-goog