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Peter Anvin" , Ard Biesheuvel , Paolo Bonzini , Sean Christopherson , Vitaly Kuznetsov , Jim Mattson , Andy Lutomirski , Dave Hansen , Sergio Lopez , Peter Zijlstra , Srinivas Pandruvada , David Rientjes , Dov Murik , Tobin Feldman-Fitzthum , Borislav Petkov , Michael Roth , Vlastimil Babka , "Kirill A . Shutemov" , Andi Kleen , Tony Luck , Marc Orr , Sathyanarayanan Kuppuswamy , Alper Gun , "Dr. David Alan Gilbert" , jarkko@kernel.org Content-Type: text/plain; charset="UTF-8" ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1656088573; a=rsa-sha256; cv=none; b=ABAUpTUr3Y/8G5eApmNUxF33cmTyfmLMZR6KM9NJzr7oLiDizFXvC16vug/XsYOs1804oy lKqnVcmMagNm+kgCifPJj/0crILdafpgUjKUJzUlIB0jGYU05VrXZYpBlZ8Uh+ivEDDOPS s4zvbwaNqipGUkNefUMuOZ2he6mqynU= ARC-Authentication-Results: i=1; imf18.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=VHI4cibU; spf=pass (imf18.hostedemail.com: domain of pgonda@google.com designates 209.85.208.171 as permitted sender) smtp.mailfrom=pgonda@google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1656088573; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=v0kR56a3js8tVSJ/80FTzZmMgZbMcBIHC4Horg01B0c=; b=O/Qw9/fmMXI7osuYTgXdD15irr3c/59IY0cOZK3ItRz8KtWe7jw4wMgiq3GaJT+rHDJKwR TBbzsssKURPVbeeW3dEPA2pp0cxm2zdOevkBaJO2nQsp1jv4JB9TSKXnbvHMeo54MIxd/G ktJ6WFFiBxSM8DGcPRsEM2H+MXbxh1Y= X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: E7C041C009B Authentication-Results: imf18.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=VHI4cibU; spf=pass (imf18.hostedemail.com: domain of pgonda@google.com designates 209.85.208.171 as permitted sender) smtp.mailfrom=pgonda@google.com; dmarc=pass (policy=reject) header.from=google.com X-Rspam-User: X-Stat-Signature: kisfjgp9hy4wwdkgitziem1m3b4w4y5f X-HE-Tag: 1656088572-767000 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Jun 20, 2022 at 5:15 PM Ashish Kalra wrote: > > From: Michael Roth > > Signed-off-by: Michael Roth Can you add a commit description here? Is this a fix for existing SEV-ES support or should this be incorporated into a patch in this series which adds this issue? > --- > arch/x86/kvm/svm/svm.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c > index fced6ea423ad..f78e3b1bde0e 100644 > --- a/arch/x86/kvm/svm/svm.c > +++ b/arch/x86/kvm/svm/svm.c > @@ -1352,7 +1352,7 @@ static void svm_vcpu_free(struct kvm_vcpu *vcpu) > static void svm_prepare_switch_to_guest(struct kvm_vcpu *vcpu) > { > struct vcpu_svm *svm = to_svm(vcpu); > - struct svm_cpu_data *sd = per_cpu(svm_data, vcpu->cpu); > + struct svm_cpu_data *sd; > > if (sev_es_guest(vcpu->kvm)) > sev_es_unmap_ghcb(svm); > @@ -1360,6 +1360,10 @@ static void svm_prepare_switch_to_guest(struct kvm_vcpu *vcpu) > if (svm->guest_state_loaded) > return; > > + /* sev_es_unmap_ghcb() can resched, so grab per-cpu pointer afterward. */ > + barrier(); > + sd = per_cpu(svm_data, vcpu->cpu); > + > /* > * Save additional host state that will be restored on VMEXIT (sev-es) > * or subsequent vmload of host save area. > -- > 2.25.1 >