From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yb1-f201.google.com (mail-yb1-f201.google.com [209.85.219.201]) (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 296351C750 for ; Fri, 2 Jun 2023 16:20:02 +0000 (UTC) Received: by mail-yb1-f201.google.com with SMTP id 3f1490d57ef6-ba8337ade1cso3117343276.2 for ; Fri, 02 Jun 2023 09:20:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1685722802; x=1688314802; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=jB6mZ6+sZkvbswM4H6nQ7omw8CujCnjIDUHOjQN9Lak=; b=WzG81VZ+IOZZWpA5d8GyyFB+GNO5rd59XBOMZDWSQkbTFSpgSDMeCniff6+7OHEij5 6hoTs84id29QOXjOw8EHoZcr4T/0ZYFYEFe944xT/JJ+tF9azU/Cuirs/Pg7/Q2L7Xpt Hq8OKt/J6F5RePSKWMF5TvjkErofFJ4JT6hlxyRWSfFhkQLu+zptKjem6S1xudWoMoSO G7hp297qXl4sRDf1NkyFEEZysCmJrGxmUW4a79PFknUySCy8Dm2g/bW4ST5IKz9IXg/M jBH17KffIsGU6XV+UNRoQBPgrqaSlxHp1aoOr9WN04DdPMDQTnEZoiXXPrCCrrMOMWbA mYgQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1685722802; x=1688314802; h=cc: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=jB6mZ6+sZkvbswM4H6nQ7omw8CujCnjIDUHOjQN9Lak=; b=ZIkzufGNdhQ0BN7KJZocfMrWJ1MuaGfRrqVUDAJ7axvkFH5O+Bou8IZ45kBtANHujZ kg4HpafFQQxxg0PoXDlXLvLeG8bSvfliLN9wwxpTBXROs/qLkSF1MzGVGqzP1iwJ1DbT QjY+fZX7VpPzqcyX6iEfQotw0xTd0UPAHhRfhVK/48tYm9gr4UY3Nb1hFHiiFDfzU9Ce 5QpwwGPTKLm4ZTOicsmARberKgJuVHBYFKNKXWIvPblFCcLSavL9HtEK5J/ENcXXRMj0 CRUunlnI/EO5nZ+PxWMAxZiH7KsYolg7080UT6+OwMqvdPulvQlxiS/lwJlo+I0kO0Wk 2maA== X-Gm-Message-State: AC+VfDxypzXWiejGa7wVzsK+j5hRc6pzV6nBqc4QcZiWc/IEttz4Fx8z +ilv1xcV+3x3deoIAOsIWtA2/sYaK2elwA== X-Google-Smtp-Source: ACHHUZ5CZs2sEm/aP6c7Rto4UGYg7s6RPhTIofLLjydHszjo7abjQfyJ+FalU2Ytv3XZVw4SIwBatK59S9rkfQ== X-Received: from laogai.c.googlers.com ([fda3:e722:ac3:cc00:2b:7d90:c0a8:2c9]) (user=amoorthy job=sendgmr) by 2002:a25:e706:0:b0:bac:5d2c:844b with SMTP id e6-20020a25e706000000b00bac5d2c844bmr1317036ybh.8.1685722802127; Fri, 02 Jun 2023 09:20:02 -0700 (PDT) Date: Fri, 2 Jun 2023 16:19:16 +0000 In-Reply-To: <20230602161921.208564-1-amoorthy@google.com> Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20230602161921.208564-1-amoorthy@google.com> X-Mailer: git-send-email 2.41.0.rc0.172.g3f132b7071-goog Message-ID: <20230602161921.208564-12-amoorthy@google.com> Subject: [PATCH v4 11/16] KVM: arm64: Implement KVM_CAP_NOWAIT_ON_FAULT From: Anish Moorthy To: seanjc@google.com, oliver.upton@linux.dev, kvm@vger.kernel.org, kvmarm@lists.linux.dev Cc: pbonzini@redhat.com, maz@kernel.org, robert.hoo.linux@gmail.com, jthoughton@google.com, amoorthy@google.com, bgardon@google.com, dmatlack@google.com, ricarkol@google.com, axelrasmussen@google.com, peterx@redhat.com, nadav.amit@gmail.com, isaku.yamahata@gmail.com Content-Type: text/plain; charset="UTF-8" Return -EFAULT from user_mem_abort when the memslot flag is enabled and fast GUP fails to find a present mapping for the page. Signed-off-by: Anish Moorthy --- Documentation/virt/kvm/api.rst | 2 +- arch/arm64/kvm/arm.c | 1 + arch/arm64/kvm/mmu.c | 16 +++++++++++++++- 3 files changed, 17 insertions(+), 2 deletions(-) diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index aa7b4024fd41..8a1205f7c271 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -7783,7 +7783,7 @@ bugs and reported to the maintainers so that annotations can be added. 7.35 KVM_CAP_NOWAIT_ON_FAULT ---------------------------- -:Architectures: x86 +:Architectures: x86, arm64 :Returns: -EINVAL. The presence of this capability indicates that userspace may pass the diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index b34cf0cedffa..46a09c4db901 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -235,6 +235,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) case KVM_CAP_IRQFD_RESAMPLE: case KVM_CAP_COUNTER_OFFSET: case KVM_CAP_MEMORY_FAULT_INFO: + case KVM_CAP_NOWAIT_ON_FAULT: r = 1; break; case KVM_CAP_SET_GUEST_DEBUG2: diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 3b9d4d24c361..5451b712b0ac 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1232,6 +1232,8 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, long vma_pagesize, fault_granule; enum kvm_pgtable_prot prot = KVM_PGTABLE_PROT_R; struct kvm_pgtable *pgt; + bool exit_on_memory_fault = kvm_slot_nowait_on_fault(memslot); + uint64_t memory_fault_flags; fault_granule = 1UL << ARM64_HW_PGTABLE_LEVEL_SHIFT(fault_level); write_fault = kvm_is_write_fault(vcpu); @@ -1325,8 +1327,20 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, mmu_seq = vcpu->kvm->mmu_invalidate_seq; mmap_read_unlock(current->mm); - pfn = __gfn_to_pfn_memslot(memslot, gfn, false, false, NULL, + pfn = __gfn_to_pfn_memslot(memslot, gfn, exit_on_memory_fault, false, NULL, write_fault, &writable, NULL); + + if (exit_on_memory_fault && pfn == KVM_PFN_ERR_FAULT) { + memory_fault_flags = 0; + if (write_fault) + memory_fault_flags |= KVM_MEMORY_FAULT_FLAG_EXEC; + if (exec_fault) + memory_fault_flags |= KVM_MEMORY_FAULT_FLAG_EXEC; + kvm_populate_efault_info(vcpu, + round_down(gfn * PAGE_SIZE, vma_pagesize), vma_pagesize, + memory_fault_flags); + return -EFAULT; + } if (pfn == KVM_PFN_ERR_HWPOISON) { kvm_send_hwpoison_signal(hva, vma_shift); return 0; -- 2.41.0.rc0.172.g3f132b7071-goog