From: Chao Gao <chao.gao@intel.com>
To: Yang Weijiang <weijiang.yang@intel.com>
Cc: <seanjc@google.com>, <pbonzini@redhat.com>,
<peterz@infradead.org>, <john.allen@amd.com>,
<kvm@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
<rick.p.edgecombe@intel.com>, <binbin.wu@linux.intel.com>
Subject: Re: [PATCH v5 15/19] KVM:x86: Optimize CET supervisor SSP save/reload
Date: Fri, 4 Aug 2023 16:43:12 +0800 [thread overview]
Message-ID: <ZMy6INjzYiVqOKEy@chao-email> (raw)
In-Reply-To: <20230803042732.88515-16-weijiang.yang@intel.com>
On Thu, Aug 03, 2023 at 12:27:28AM -0400, Yang Weijiang wrote:
>Make PL{0,1,2}_SSP as write-intercepted to detect whether
>guest is using these MSRs. Disable intercept to the MSRs
>if they're written with non-zero values. KVM does save/
>reload for the MSRs only if they're used by guest.
What would happen if guest tries to use XRSTORS to load S_CET state from a
xsave area without any writes to the PL0-2_SSP (i.e., at that point, writes to
the MSRs are still intercepted)?
>@@ -2420,6 +2432,14 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
> else
> vmx->pt_desc.guest.addr_a[index / 2] = data;
> break;
>+ case MSR_IA32_PL0_SSP ... MSR_IA32_PL2_SSP:
>+ if (kvm_set_msr_common(vcpu, msr_info))
>+ return 1;
>+ if (data) {
>+ vmx_disable_write_intercept_sss_msr(vcpu);
>+ wrmsrl(msr_index, data);
Is it necessary to do the wrmsl()?
looks the next kvm_x86_prepare_switch_to_guest() will load PL0-2_SSP from the
caching values.
next prev parent reply other threads:[~2023-08-04 8:44 UTC|newest]
Thread overview: 82+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-08-03 4:27 [PATCH v5 00/19] Enable CET Virtualization Yang Weijiang
2023-08-03 4:27 ` [PATCH v5 01/19] x86/cpufeatures: Add CPU feature flags for shadow stacks Yang Weijiang
2023-08-03 4:27 ` [PATCH v5 02/19] x86/fpu/xstate: Introduce CET MSR and XSAVES supervisor states Yang Weijiang
2023-08-03 4:27 ` [PATCH v5 03/19] KVM:x86: Report XSS as to-be-saved if there are supported features Yang Weijiang
2023-08-03 4:27 ` [PATCH v5 04/19] KVM:x86: Refresh CPUID on write to guest MSR_IA32_XSS Yang Weijiang
2023-08-04 16:02 ` Sean Christopherson
2023-08-04 21:43 ` Paolo Bonzini
2023-08-09 3:11 ` Yang, Weijiang
2023-08-08 14:20 ` Yang, Weijiang
2023-08-04 18:27 ` Sean Christopherson
2023-08-07 6:55 ` Paolo Bonzini
2023-08-09 8:56 ` Yang, Weijiang
2023-08-10 0:01 ` Paolo Bonzini
2023-08-10 1:12 ` Yang, Weijiang
2023-08-03 4:27 ` [PATCH v5 05/19] KVM:x86: Initialize kvm_caps.supported_xss Yang Weijiang
2023-08-04 18:45 ` Sean Christopherson
2023-08-08 15:08 ` Yang, Weijiang
2023-08-03 4:27 ` [PATCH v5 06/19] KVM:x86: Load guest FPU state when access XSAVE-managed MSRs Yang Weijiang
2023-08-03 4:27 ` [PATCH v5 07/19] KVM:x86: Add fault checks for guest CR4.CET setting Yang Weijiang
2023-08-03 9:07 ` Chao Gao
2023-08-03 4:27 ` [PATCH v5 08/19] KVM:x86: Report KVM supported CET MSRs as to-be-saved Yang Weijiang
2023-08-03 10:39 ` Chao Gao
2023-08-04 3:13 ` Yang, Weijiang
2023-08-04 5:51 ` Chao Gao
2023-08-04 18:51 ` Sean Christopherson
2023-08-04 22:01 ` Paolo Bonzini
2023-08-08 15:16 ` Yang, Weijiang
2023-08-06 8:54 ` Yang, Weijiang
2023-08-04 18:55 ` Sean Christopherson
2023-08-08 15:26 ` Yang, Weijiang
2023-08-04 21:47 ` Paolo Bonzini
2023-08-09 3:14 ` Yang, Weijiang
2023-08-03 4:27 ` [PATCH v5 09/19] KVM:x86: Make guest supervisor states as non-XSAVE managed Yang Weijiang
2023-08-03 11:15 ` Chao Gao
2023-08-04 3:26 ` Yang, Weijiang
2023-08-04 20:45 ` Sean Christopherson
2023-08-04 20:59 ` Peter Zijlstra
2023-08-04 21:32 ` Paolo Bonzini
2023-08-09 2:51 ` Yang, Weijiang
2023-08-09 2:39 ` Yang, Weijiang
2023-08-10 9:29 ` Yang, Weijiang
2023-08-10 14:29 ` Dave Hansen
2023-08-10 15:15 ` Paolo Bonzini
2023-08-10 15:37 ` Sean Christopherson
2023-08-11 3:03 ` Yang, Weijiang
2023-08-28 21:00 ` Dave Hansen
2023-08-29 7:05 ` Yang, Weijiang
2023-08-03 4:27 ` [PATCH v5 10/19] KVM:VMX: Introduce CET VMCS fields and control bits Yang Weijiang
2023-08-03 4:27 ` [PATCH v5 11/19] KVM:VMX: Emulate read and write to CET MSRs Yang Weijiang
2023-08-04 5:14 ` Chao Gao
2023-08-04 21:27 ` Sean Christopherson
2023-08-04 21:45 ` Paolo Bonzini
2023-08-04 22:21 ` Sean Christopherson
2023-08-07 7:03 ` Paolo Bonzini
2023-08-06 8:44 ` Yang, Weijiang
2023-08-07 7:00 ` Paolo Bonzini
2023-08-04 8:28 ` Chao Gao
2023-08-09 7:12 ` Yang, Weijiang
2023-08-04 21:40 ` Paolo Bonzini
2023-08-09 3:05 ` Yang, Weijiang
2023-08-03 4:27 ` [PATCH v5 12/19] KVM:x86: Save and reload SSP to/from SMRAM Yang Weijiang
2023-08-04 7:53 ` Chao Gao
2023-08-04 15:25 ` Sean Christopherson
2023-08-06 9:14 ` Yang, Weijiang
2023-08-03 4:27 ` [PATCH v5 13/19] KVM:VMX: Set up interception for CET MSRs Yang Weijiang
2023-08-04 8:16 ` Chao Gao
2023-08-06 9:22 ` Yang, Weijiang
2023-08-07 1:16 ` Chao Gao
2023-08-09 6:11 ` Yang, Weijiang
2023-08-03 4:27 ` [PATCH v5 14/19] KVM:VMX: Set host constant supervisor states to VMCS fields Yang Weijiang
2023-08-04 8:23 ` Chao Gao
2023-08-03 4:27 ` [PATCH v5 15/19] KVM:x86: Optimize CET supervisor SSP save/reload Yang Weijiang
2023-08-04 8:43 ` Chao Gao [this message]
2023-08-09 9:00 ` Yang, Weijiang
2023-08-03 4:27 ` [PATCH v5 16/19] KVM:x86: Enable CET virtualization for VMX and advertise to userspace Yang Weijiang
2023-08-03 4:27 ` [PATCH v5 17/19] KVM:x86: Enable guest CET supervisor xstate bit support Yang Weijiang
2023-08-04 22:02 ` Paolo Bonzini
2023-08-09 6:07 ` Yang, Weijiang
2023-08-03 4:27 ` [PATCH v5 18/19] KVM:nVMX: Refine error code injection to nested VM Yang Weijiang
2023-08-04 21:38 ` Sean Christopherson
2023-08-09 3:00 ` Yang, Weijiang
2023-08-03 4:27 ` [PATCH v5 19/19] KVM:nVMX: Enable CET support for " Yang Weijiang
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=ZMy6INjzYiVqOKEy@chao-email \
--to=chao.gao@intel.com \
--cc=binbin.wu@linux.intel.com \
--cc=john.allen@amd.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=pbonzini@redhat.com \
--cc=peterz@infradead.org \
--cc=rick.p.edgecombe@intel.com \
--cc=seanjc@google.com \
--cc=weijiang.yang@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).