linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Paolo Bonzini <pbonzini@redhat.com>
To: Sasha Levin <sashal@kernel.org>,
	linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Maxim Levitsky <mlevitsk@redhat.com>,
	tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
	x86@kernel.org, kvm@vger.kernel.org
Subject: Re: [PATCH MANUALSEL 5.14 4/9] KVM: x86: reset pdptrs_from_userspace when exiting smm
Date: Wed, 6 Oct 2021 15:36:29 +0200	[thread overview]
Message-ID: <e5b8a6d4-6d5c-ada9-bb36-7ed3c8b7d637@redhat.com> (raw)
In-Reply-To: <20211006133021.271905-4-sashal@kernel.org>

On 06/10/21 15:30, Sasha Levin wrote:
> From: Maxim Levitsky <mlevitsk@redhat.com>
> 
> [ Upstream commit 37687c403a641f251cb2ef2e7830b88aa0647ba9 ]
> 
> When exiting SMM, pdpts are loaded again from the guest memory.
> 
> This fixes a theoretical bug, when exit from SMM triggers entry to the
> nested guest which re-uses some of the migration
> code which uses this flag as a workaround for a legacy userspace.
> 
> Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
> Message-Id: <20210913140954.165665-4-mlevitsk@redhat.com>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> ---
>   arch/x86/kvm/x86.c | 7 +++++++
>   1 file changed, 7 insertions(+)
> 
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index b3f855d48f72..1e7d629bbf36 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -7659,6 +7659,13 @@ static void kvm_smm_changed(struct kvm_vcpu *vcpu, bool entering_smm)
>   
>   		/* Process a latched INIT or SMI, if any.  */
>   		kvm_make_request(KVM_REQ_EVENT, vcpu);
> +
> +		/*
> +		 * Even if KVM_SET_SREGS2 loaded PDPTRs out of band,
> +		 * on SMM exit we still need to reload them from
> +		 * guest memory
> +		 */
> +		vcpu->arch.pdptrs_from_userspace = false;
>   	}
>   
>   	kvm_mmu_reset_context(vcpu);
> 

Acked-by: Paolo Bonzini <pbonzini@redhat.com>


  reply	other threads:[~2021-10-06 13:36 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-10-06 13:30 [PATCH MANUALSEL 5.14 1/9] selftests: KVM: Align SMCCC call with the spec in steal_time Sasha Levin
2021-10-06 13:30 ` [PATCH MANUALSEL 5.14 2/9] KVM: x86: Handle SRCU initialization failure during page track init Sasha Levin
2021-10-06 13:36   ` Paolo Bonzini
2021-10-06 13:30 ` [PATCH MANUALSEL 5.14 3/9] KVM: do not shrink halt_poll_ns below grow_start Sasha Levin
2021-10-06 13:36   ` Paolo Bonzini
2021-10-06 13:30 ` [PATCH MANUALSEL 5.14 4/9] KVM: x86: reset pdptrs_from_userspace when exiting smm Sasha Levin
2021-10-06 13:36   ` Paolo Bonzini [this message]
2021-10-07 15:23     ` Naresh Kamboju
2021-10-07 17:47       ` Paolo Bonzini
2021-10-06 13:30 ` [PATCH MANUALSEL 5.14 5/9] KVM: x86: VMX: synthesize invalid VM exit when emulating invalid guest state Sasha Levin
2021-10-06 13:35   ` Paolo Bonzini
2021-10-06 13:30 ` [PATCH MANUALSEL 5.14 6/9] KVM: x86: nVMX: don't fail nested VM entry on invalid guest state if !from_vmentry Sasha Levin
2021-10-06 13:36   ` Paolo Bonzini
2021-10-06 13:30 ` [PATCH MANUALSEL 5.14 7/9] kvm: x86: Add AMD PMU MSRs to msrs_to_save_all[] Sasha Levin
2021-10-06 13:36   ` Paolo Bonzini
2021-10-06 13:30 ` [PATCH MANUALSEL 5.14 8/9] KVM: x86: nSVM: restore int_vector in svm_clear_vintr Sasha Levin
2021-10-06 13:36   ` Paolo Bonzini
2021-10-06 13:30 ` [PATCH MANUALSEL 5.14 9/9] ALSA: pcsp: Make hrtimer forwarding more robust Sasha Levin
2021-10-06 13:36 ` [PATCH MANUALSEL 5.14 1/9] selftests: KVM: Align SMCCC call with the spec in steal_time Paolo Bonzini

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=e5b8a6d4-6d5c-ada9-bb36-7ed3c8b7d637@redhat.com \
    --to=pbonzini@redhat.com \
    --cc=bp@alien8.de \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=mlevitsk@redhat.com \
    --cc=sashal@kernel.org \
    --cc=stable@vger.kernel.org \
    --cc=tglx@linutronix.de \
    --cc=x86@kernel.org \
    /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).