From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CF3FB44C508; Mon, 31 Aug 2026 13:42:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788183758; cv=none; b=CgGTZow6JywdnBu0dx4jPvtTxI0okPZPihn71vreyKa3Sxuzqucjh8om0Zf0FuuMdRw/bwhTpp3HvWNud+6u01GSgpw+KrOvmry339KkDdE327PCivWaf5h/weg1zPTUEakVA83Nayd18MzUrTO2ziWWZuzRLorRdiZfKRWu5Hg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788183758; c=relaxed/simple; bh=DktWv7aXbnJXnXPDeiXHK6i5kr/rGM3NcXidzvRejcY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=N/Zdj9P0B8J02FJbphz0xUNQj8WXbYFdFd6aa49taH4LuSfhxpuyxAbCiRKK2F9ivQlFYgVOeLYRMad71PUc7Le8Mq3EwSsac9f/xov9bia72nlqsBo9upgSjlRvPQxuxgqE0ZkLSL5CXdGkmAQ1mZp/eSstVfn1lzkS+A9ynEE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=VPoTmNst; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="VPoTmNst" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2124A1F00ACA; Mon, 31 Aug 2026 13:42:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788183756; bh=N/OxTtREnItpf/te1zE/aDiBj9GfqkkimVcJ02hE86w=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=VPoTmNstqVeXy+un9G4sg8NpMjp0NXEnMjUvpSNkK0yN7WxZJgm07Zqm3MFRH9kMT tnH7VcGVIg2BOIQQwt9USfn8k2eGfR8ru2YvzOfSqEIJBzrNgbP7JOV22HsP0/raDd rm7qJeHkpoUGcrHfVHK0v9Dv6f1r7SXdiGin0uYw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Michael Roth , Sean Christopherson Subject: [PATCH 7.1 32/76] KVM: SEV: Mark vCPU RUNNABLE after AP_CREATE, even if VMSA is unusable Date: Mon, 31 Aug 2026 15:34:04 +0200 Message-ID: <20260831133401.021833801@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260831133359.185608553@linuxfoundation.org> References: <20260831133359.185608553@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sean Christopherson commit 98ade8c48c28c227fe2e80e545ff0c57cd4712a3 upstream. Always mark the vCPU as RUNNABLE after responding to AP_CREATE, even if the guest-specified VMSA is unusable, e.g. isn't backed by a memslot or doesn't have a backing guest_memfd page. If the VMSA is unusable, leaving the vCPU in a non-running state will effectively hang the vCPU instead of reporting an error to userspace. This will also allow retrying the VMSA load in the future, to fix a bug where KVM doesn't honor guest_memfd invalidation events, e.g. if AP_CREATION races with PUNCH_HOLE. Cc: stable@vger.kernel.org # 6.12.x Reviewed-by: Michael Roth Link: https://patch.msgid.link/20260709204948.1988414-4-seanjc@google.com Signed-off-by: Sean Christopherson Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/svm/sev.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -4134,9 +4134,6 @@ static void sev_snp_reload_vmsa(struct k svm->sev_es.snp_guest_vmsa_gpa = gpa; svm->vmcb->control.vmsa_pa = pfn_to_hpa(pfn); - /* Mark the vCPU as runnable */ - kvm_set_mp_state(vcpu, KVM_MP_STATE_RUNNABLE); - /* * gmem pages aren't currently migratable, but if this ever changes * then care should be taken to ensure svm->sev_es.vmsa is pinned @@ -4168,6 +4165,15 @@ static void sev_snp_init_protected_guest svm->sev_es.snp_pending_vmsa_gpa = INVALID_PAGE; sev_snp_reload_vmsa(vcpu, gpa); + + /* + * Mark the vCPU as runnable for CREATE requests, indicated by a valid + * VMSA GPA, even if installing the VMSA failed, so that KVM_RUN will + * fail instead of blocking indefinitely and hanging the vCPU, e.g. if + * the backing guest_memfd page is unavailable. + */ + if (VALID_PAGE(gpa)) + kvm_set_mp_state(vcpu, KVM_MP_STATE_RUNNABLE); } static int sev_snp_ap_creation(struct vcpu_svm *svm)