From: Vishal Annapurve <vannapurve@google.com>
To: x86@kernel.org, kvm@vger.kernel.org,
linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org
Cc: pbonzini@redhat.com, vkuznets@redhat.com, wanpengli@tencent.com,
jmattson@google.com, joro@8bytes.org, tglx@linutronix.de,
mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com,
hpa@zytor.com, shuah@kernel.org, yang.zhong@intel.com,
ricarkol@google.com, aaronlewis@google.com, wei.w.wang@intel.com,
kirill.shutemov@linux.intel.com, corbet@lwn.net,
hughd@google.com, jlayton@kernel.org, bfields@fieldses.org,
akpm@linux-foundation.org, chao.p.peng@linux.intel.com,
yu.c.zhang@linux.intel.com, jun.nakajima@intel.com,
dave.hansen@intel.com, michael.roth@amd.com, qperret@google.com,
steven.price@arm.com, ak@linux.intel.com, david@redhat.com,
luto@kernel.org, vbabka@suse.cz, marcorr@google.com,
erdemaktas@google.com, pgonda@google.com, nikunj@amd.com,
seanjc@google.com, diviness@google.com, maz@kernel.org,
dmatlack@google.com, axelrasmussen@google.com,
maciej.szmigiero@oracle.com, mizhang@google.com,
bgardon@google.com, ackerleytng@google.com,
Vishal Annapurve <vannapurve@google.com>
Subject: [V1 PATCH 1/6] KVM: x86: Add support for testing private memory
Date: Fri, 11 Nov 2022 01:42:39 +0000 [thread overview]
Message-ID: <20221111014244.1714148-2-vannapurve@google.com> (raw)
In-Reply-To: <20221111014244.1714148-1-vannapurve@google.com>
Introduce HAVE_KVM_PRIVATE_MEM_TESTING config to be able to test fd based
approach to support private memory with non-confidential selftest VMs.
To support this testing few important aspects need to be considered from
the perspective of selftests -
* KVM needs to know whether the access from guest VM is private or shared.
Confidential VMs (SNP/TDX) carry a dedicated bit in gpa that can be used by
KVM to deduce the nature of the access.
Non-confidential VMs don't have mechanism to carry/convey such an
information to KVM. So KVM just relies on what attributes are set by
userspace VMM keeping the userspace VMM in the TCB for the testing
purposes.
* arch_private_mem_supported is updated to allow private memory logic to
work with non-confidential vm selftests.
Signed-off-by: Vishal Annapurve <vannapurve@google.com>
---
arch/x86/kvm/mmu/mmu.c | 4 ++++
arch/x86/kvm/mmu/mmu_internal.h | 4 +++-
virt/kvm/Kconfig | 4 ++++
virt/kvm/kvm_main.c | 2 +-
4 files changed, 12 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 10017a9f26ee..b3118d00b284 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4280,6 +4280,10 @@ static int direct_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault
fault->gfn = fault->addr >> PAGE_SHIFT;
fault->slot = kvm_vcpu_gfn_to_memslot(vcpu, fault->gfn);
+#ifdef CONFIG_HAVE_KVM_PRIVATE_MEM_TESTING
+ fault->is_private = kvm_slot_can_be_private(fault->slot) &&
+ kvm_mem_is_private(vcpu->kvm, fault->gfn);
+#endif
if (page_fault_handle_page_track(vcpu, fault))
return RET_PF_EMULATE;
diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index 5cdff5ca546c..2e759f39c2c5 100644
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -188,7 +188,6 @@ struct kvm_page_fault {
/* Derived from mmu and global state. */
const bool is_tdp;
- const bool is_private;
const bool nx_huge_page_workaround_enabled;
/*
@@ -221,6 +220,9 @@ struct kvm_page_fault {
/* The memslot containing gfn. May be NULL. */
struct kvm_memory_slot *slot;
+ /* Derived from encryption bits of the faulting GPA for CVMs. */
+ bool is_private;
+
/* Outputs of kvm_faultin_pfn. */
kvm_pfn_t pfn;
hva_t hva;
diff --git a/virt/kvm/Kconfig b/virt/kvm/Kconfig
index 69ca59e82149..300876afb0ca 100644
--- a/virt/kvm/Kconfig
+++ b/virt/kvm/Kconfig
@@ -93,3 +93,7 @@ config HAVE_KVM_RESTRICTED_MEM
config KVM_GENERIC_PRIVATE_MEM
bool
depends on HAVE_KVM_RESTRICTED_MEM
+
+config HAVE_KVM_PRIVATE_MEM_TESTING
+ bool
+ depends on KVM_GENERIC_PRIVATE_MEM
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index dae6a2c196ad..54e57b7f1c15 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1750,7 +1750,7 @@ static void kvm_replace_memslot(struct kvm *kvm,
bool __weak kvm_arch_has_private_mem(struct kvm *kvm)
{
- return false;
+ return IS_ENABLED(CONFIG_HAVE_KVM_PRIVATE_MEM_TESTING);
}
static int check_memory_region_flags(struct kvm *kvm,
--
2.38.1.431.g37b22c650d-goog
next prev parent reply other threads:[~2022-11-11 1:43 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-11-11 1:42 [V1 PATCH 0/6] selftests: KVM: selftests for fd-based private memory Vishal Annapurve
2022-11-11 1:42 ` Vishal Annapurve [this message]
2022-11-22 10:07 ` [V1 PATCH 1/6] KVM: x86: Add support for testing " Chao Peng
2022-11-22 20:06 ` Sean Christopherson
2022-11-24 1:49 ` Marc Orr
2022-11-28 16:21 ` Sean Christopherson
2022-11-24 13:17 ` Chao Peng
2022-12-02 0:26 ` Michael Roth
2022-11-11 1:42 ` [V1 PATCH 2/6] KVM: Selftests: Add support for " Vishal Annapurve
2022-11-11 1:42 ` [V1 PATCH 3/6] KVM: selftests: x86: Add IS_ALIGNED/IS_PAGE_ALIGNED helpers Vishal Annapurve
2022-11-11 1:42 ` [V1 PATCH 4/6] KVM: selftests: x86: Execute VMs with private memory Vishal Annapurve
2022-11-14 19:37 ` Peter Gonda
2022-11-15 1:53 ` Vishal Annapurve
2022-12-08 21:56 ` Vishal Annapurve
2022-11-11 1:42 ` [V1 PATCH 5/6] KVM: selftests: Add get_free_huge_2m_pages Vishal Annapurve
2022-11-11 1:42 ` [V1 PATCH 6/6] KVM: selftests: x86: Add selftest for private memory Vishal Annapurve
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20221111014244.1714148-2-vannapurve@google.com \
--to=vannapurve@google.com \
--cc=aaronlewis@google.com \
--cc=ackerleytng@google.com \
--cc=ak@linux.intel.com \
--cc=akpm@linux-foundation.org \
--cc=axelrasmussen@google.com \
--cc=bfields@fieldses.org \
--cc=bgardon@google.com \
--cc=bp@alien8.de \
--cc=chao.p.peng@linux.intel.com \
--cc=corbet@lwn.net \
--cc=dave.hansen@intel.com \
--cc=dave.hansen@linux.intel.com \
--cc=david@redhat.com \
--cc=diviness@google.com \
--cc=dmatlack@google.com \
--cc=erdemaktas@google.com \
--cc=hpa@zytor.com \
--cc=hughd@google.com \
--cc=jlayton@kernel.org \
--cc=jmattson@google.com \
--cc=joro@8bytes.org \
--cc=jun.nakajima@intel.com \
--cc=kirill.shutemov@linux.intel.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-kselftest@vger.kernel.org \
--cc=luto@kernel.org \
--cc=maciej.szmigiero@oracle.com \
--cc=marcorr@google.com \
--cc=maz@kernel.org \
--cc=michael.roth@amd.com \
--cc=mingo@redhat.com \
--cc=mizhang@google.com \
--cc=nikunj@amd.com \
--cc=pbonzini@redhat.com \
--cc=pgonda@google.com \
--cc=qperret@google.com \
--cc=ricarkol@google.com \
--cc=seanjc@google.com \
--cc=shuah@kernel.org \
--cc=steven.price@arm.com \
--cc=tglx@linutronix.de \
--cc=vbabka@suse.cz \
--cc=vkuznets@redhat.com \
--cc=wanpengli@tencent.com \
--cc=wei.w.wang@intel.com \
--cc=x86@kernel.org \
--cc=yang.zhong@intel.com \
--cc=yu.c.zhang@linux.intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).