From patchwork Wed Oct 9 15:49:39 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 13828687 Received: from mail-pj1-f73.google.com (mail-pj1-f73.google.com [209.85.216.73]) (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 8D99F1E32D1 for ; Wed, 9 Oct 2024 15:49:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.73 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728488998; cv=none; b=iC8az5QdtVRoJ8ZJfTR3UcEiw/PBl95rNsK+5QeTQJJPAhhBToOAk79mUSAi2TxdlDjskGfMYwFKrZrM2OsY6owJKB+Hf1U2OqzmyzGTNTcH4XJfMEn8gwjrcuc7cmb80vJh7wNSaz6yNPdHDwBOpjv/bvsHyEmA07vHWiXFqLM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728488998; c=relaxed/simple; bh=lSrxQ0o4lzW28SX3OpFxYNNm5zyTaJtY872EDLEASgA=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=Yz+sMQ144baK0J2QWzl0sx5CAaZgsDGfZ4HHMHjwsYKKqCfdM+CfkddCb5917rprIL62U7lM2zzXeZ1zE7PJmS791etDygYvdtTnpeupuJVstTGi2Zg0FDju0sHwwMDyDp9VUnrJS2mDU46sax1FigSw4nCSmeo0Qa0Ua7kCtyw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=PVcHGzag; arc=none smtp.client-ip=209.85.216.73 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--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="PVcHGzag" Received: by mail-pj1-f73.google.com with SMTP id 98e67ed59e1d1-2e292f3e85fso304a91.2 for ; Wed, 09 Oct 2024 08:49:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1728488996; x=1729093796; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:reply-to:from:to:cc :subject:date:message-id:reply-to; bh=mp1GmMvEsdG1xOqt7J6qefXNw1tx4nozkIWjiF4j3SI=; b=PVcHGzag1ufwUKkgc0jFS5LtMuZyZQaR0RVDBF0NgNbA6XHuUWSfHCWMQHewhayKVi fTDxjQ3/9CrutAbmcPlMPJiSdNJ3dVXfqOtZ92vQfT5TUu5pOOpekt13Ilj7kXTR9H0b 7D+aXFTKxU6D4HCAUz3J2nKUU3qWeSIY1Iw5hT4WEOTVhZTvga0Yi2FAHfWF3M6mF5Ll nQRQ1qrgMkoeXrlosMeHiokof/xr1J8em69OCh/bd3VYDhQFizw3CdhvSiafxk51jUes +BEnSBbiBS4j8HLxoRpCwjVWu2gz8BeZjlNn4nmFL0u5t8hFKavVQTul0FB28PUBQVZ9 IilQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1728488996; x=1729093796; h=cc:to:from:subject:message-id:mime-version:date:reply-to :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=mp1GmMvEsdG1xOqt7J6qefXNw1tx4nozkIWjiF4j3SI=; b=RjzFXuY3VLxauiw7pYG4ur2svhqAEGguvCz5EAEfr7R23kAYIA/VZIDGN8LtWRohlI 1AgTnMBFZoGgLZcwp244z0ymwVOgQFOhrAjt4lRblOM08YJCnVco+U/rLQr+C582Hsef /ccSUuwE1D+aIZ5Hw+9km1gf0+FddJZiOaDS4aQE8EIcueFq141QayBN6eh3ED017ms3 Z+OQ4cEZyDqxFyAwImaE/coqLALACVD49xPb4kCQ39ikFG/y3yoqEV0WZ26kqkkDQISd uaQEk5HSlG0J4SzTAqiZl+da6/WWNLKFBxv/xTRGsxuhZfJp39uMyLMYpiktf5JNk0GZ LJsQ== X-Forwarded-Encrypted: i=1; AJvYcCWfWAmX0d3bd8sp/P034sXV/41VVyMDlH7YYuIKhIeKUAn9IOUGscpVQIkENLF21U8CiA0=@vger.kernel.org X-Gm-Message-State: AOJu0YzrQAueG+FatbI7jTEzlvqS37pxJQEyaVczb6b1lRhhJe0OklIM cvZz5IysLpplOWojI6nU6RnidLlyFd/3mhaNjpepJyEjaz2XtqdzY5EyW7OE+ojizIL0BGZ4u/1 3yg== X-Google-Smtp-Source: AGHT+IEKF1Ho4VsrxKapa7g6WWX3VRxIkgUDz21gNBA5z4SeEUBMmHmDj2XN+crbLzcKc/g4iyRtc0M+qRE= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:9d:3983:ac13:c240]) (user=seanjc job=sendgmr) by 2002:a17:90a:468a:b0:2e0:6c40:e384 with SMTP id 98e67ed59e1d1-2e2a251444emr3074a91.4.1728488995562; Wed, 09 Oct 2024 08:49:55 -0700 (PDT) Reply-To: Sean Christopherson Date: Wed, 9 Oct 2024 08:49:39 -0700 Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.47.0.rc0.187.ge670bccf7e-goog Message-ID: <20241009154953.1073471-1-seanjc@google.com> Subject: [PATCH v3 00/14] KVM: selftests: Morph max_guest_mem to mmu_stress From: Sean Christopherson To: Marc Zyngier , Oliver Upton , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Paolo Bonzini , Christian Borntraeger , Janosch Frank , Claudio Imbrenda Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Sean Christopherson , Andrew Jones , James Houghton The main purpose of this series is to convert the max_guest_memory_test into a more generic mmu_stress_test. The basic gist of the "conversion" is to have the test do mprotect() on guest memory while vCPUs are accessing said memory, e.g. to verify KVM and mmu_notifiers are working as intended. Patches 1-4 are a somewhat unexpected side quest. The original plan was that patch 3 would be a single patch, but things snowballed. Patch 3 reworks vcpu_get_reg() to return a value instead of using an out-param. This is the entire motivation for including these patches; having to define a variable just to bump the program counter on arm64 annoyed me. Patch 4 adds hardening to vcpu_{g,s}et_reg() to detect potential truncation, as KVM's uAPI allows for registers greater than the 64 bits that are supported in the "outer" selftests APIs ((vcpu_set_reg() takes a u64, vcpu_get_reg() now returns a u64). Patch 1 is a change to KVM's uAPI headers to move the KVM_REG_SIZE definition to common code so that the selftests side of things doesn't need #ifdefs to implement the hardening in patch 4. Patch 2 is the truly unexpected part. With the vcpu_get_reg() rework, arm64's vpmu_counter_test fails when compiled with gcc-13, and on gcc-11 with an added "noinline". Long story short, selftests are being compiled with strict aliasing enabled, which allows the compiler to optimize away "u64 *" => "uint64_t *" casts as u64 (unsigned long long) and uint64_t (unsigned long) are technically not aliases of each other. *sigh* v3: - Rebased onto v6.12-rc2. - Disable strict aliasing to fix the PMCR snafu. - Collect reviews. [Drew] - Minor changelog fixes. [Drew] - Include ucall_common.h to prep for RISC-V. [Drew] v2: - Rebase onto kvm/next. - Add the aforementioned vcpu_get_reg() changes/disaster. - Actually add arm64 support for the fancy mprotect() testcase (I did this before v1, but managed to forget to include the changes when posting). - Emit "mov %rax, (%rax)" on x86. [James] - Add a comment to explain the fancy mprotect() vs. vCPUs logic. - Drop the KVM x86 patches (applied and/or will be handled separately). v1: https://lore.kernel.org/all/20240809194335.1726916-1-seanjc@google.com Sean Christopherson (14): KVM: Move KVM_REG_SIZE() definition to common uAPI header KVM: selftests: Disable strict aliasing KVM: selftests: Return a value from vcpu_get_reg() instead of using an out-param KVM: selftests: Assert that vcpu_{g,s}et_reg() won't truncate KVM: selftests: Check for a potential unhandled exception iff KVM_RUN succeeded KVM: selftests: Rename max_guest_memory_test to mmu_stress_test KVM: selftests: Only muck with SREGS on x86 in mmu_stress_test KVM: selftests: Compute number of extra pages needed in mmu_stress_test KVM: sefltests: Explicitly include ucall_common.h in mmu_stress_test.c KVM: selftests: Enable mmu_stress_test on arm64 KVM: selftests: Use vcpu_arch_put_guest() in mmu_stress_test KVM: selftests: Precisely limit the number of guest loops in mmu_stress_test KVM: selftests: Add a read-only mprotect() phase to mmu_stress_test KVM: selftests: Verify KVM correctly handles mprotect(PROT_READ) arch/arm64/include/uapi/asm/kvm.h | 3 - arch/riscv/include/uapi/asm/kvm.h | 3 - include/uapi/linux/kvm.h | 4 + tools/testing/selftests/kvm/Makefile | 11 +- .../selftests/kvm/aarch64/aarch32_id_regs.c | 10 +- .../selftests/kvm/aarch64/debug-exceptions.c | 4 +- .../selftests/kvm/aarch64/hypercalls.c | 6 +- .../selftests/kvm/aarch64/no-vgic-v3.c | 2 +- .../testing/selftests/kvm/aarch64/psci_test.c | 6 +- .../selftests/kvm/aarch64/set_id_regs.c | 18 +- .../kvm/aarch64/vpmu_counter_access.c | 19 +- .../testing/selftests/kvm/include/kvm_util.h | 10 +- .../selftests/kvm/lib/aarch64/processor.c | 8 +- tools/testing/selftests/kvm/lib/kvm_util.c | 3 +- .../selftests/kvm/lib/riscv/processor.c | 66 +++---- ..._guest_memory_test.c => mmu_stress_test.c} | 162 ++++++++++++++++-- .../testing/selftests/kvm/riscv/arch_timer.c | 2 +- .../testing/selftests/kvm/riscv/ebreak_test.c | 2 +- .../selftests/kvm/riscv/sbi_pmu_test.c | 2 +- tools/testing/selftests/kvm/s390x/resets.c | 2 +- tools/testing/selftests/kvm/steal_time.c | 3 +- 21 files changed, 241 insertions(+), 105 deletions(-) rename tools/testing/selftests/kvm/{max_guest_memory_test.c => mmu_stress_test.c} (60%) base-commit: 8cf0b93919e13d1e8d4466eb4080a4c4d9d66d7b