From nobody Tue Feb 10 00:38:43 2026 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 29CE729B76B for ; Mon, 12 May 2025 18:04:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747073095; cv=none; b=D64NctGXXiD64sloYtHvDdtzNb97AWSOBprQ0vlXAMxqZI5oym7TjuFRtREHPc0ssxGRHJGiX2u0aL1kG+5pP/e4IGUCIwDaL97ynrkngnFjW+KN92Hz0RHFcIORCLG3vs50g6s7n0k4aCt2keP6HpXbKfae3k+LxtsVO2LducE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747073095; c=relaxed/simple; bh=oiXTP7GjIgf+KmXueG6Az0Eq8s4f06kD4cWloaCRxtY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nk3lv1wgofs5e9075b9quiHZPPvg/mtRWtmK8eJrdRNj0ShkpjqzBeEZAAjiFQnlN/L+8GtpJ6R29hWERYymE05btB4oAulGz8zZkQpvYxYjDwkZ50zKwDzGYg7WdTd0Fa+QsSH7hLJSm3hl0T2Lutv0np1TjD/Sd2bbSfA6jyI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=TKr5FRcy; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="TKr5FRcy" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1747073093; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Q6PrbmwQ6A0Seyvbao8fqw7a8VX7wKunfxAgqBK7Cp0=; b=TKr5FRcyaLdOuRPbB/eU3ELiDWL4kBeCgQ4y3cTStl4DcyCMrQWaGMaMxRV3eC9vK/JKZs MMon5PHCfPxJW51QWOvQoLDChl0ZNaROktaTrQOiGNHSJ9rF4rNI8lLmXro30k+3s6ofV6 P9eqLOxiRWlXjVP+K1G4f8lHaFZVu0g= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-130-mGHcVdicNDaIEHmdxj9Oxw-1; Mon, 12 May 2025 14:04:49 -0400 X-MC-Unique: mGHcVdicNDaIEHmdxj9Oxw-1 X-Mimecast-MFC-AGG-ID: mGHcVdicNDaIEHmdxj9Oxw_1747073085 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 894251800373; Mon, 12 May 2025 18:04:45 +0000 (UTC) Received: from intellaptop.lan (unknown [10.22.80.5]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id E1A5830002D4; Mon, 12 May 2025 18:04:39 +0000 (UTC) From: Maxim Levitsky To: kvm@vger.kernel.org Cc: Suzuki K Poulose , Jing Zhang , "H. Peter Anvin" , Sebastian Ott , Shusen Li , Waiman Long , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, Bjorn Helgaas , Borislav Petkov , Anup Patel , Will Deacon , Palmer Dabbelt , Alexander Potapenko , kvmarm@lists.linux.dev, Keisuke Nishimura , Zenghui Yu , Peter Zijlstra , Atish Patra , Joey Gouly , x86@kernel.org, Marc Zyngier , Sean Christopherson , Andre Przywara , Kunkun Jiang , linux-riscv@lists.infradead.org, Randy Dunlap , Paolo Bonzini , Boqun Feng , Catalin Marinas , Alexandre Ghiti , linux-kernel@vger.kernel.org, Dave Hansen , Oliver Upton , kvm-riscv@lists.infradead.org, Maxim Levitsky , Ingo Molnar , Paul Walmsley , Albert Ou Subject: [PATCH v5 4/6] x86: KVM: SVM: use kvm_lock_all_vcpus instead of a custom implementation Date: Mon, 12 May 2025 14:04:05 -0400 Message-ID: <20250512180407.659015-5-mlevitsk@redhat.com> In-Reply-To: <20250512180407.659015-1-mlevitsk@redhat.com> References: <20250512180407.659015-1-mlevitsk@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 Content-Type: text/plain; charset="utf-8" Use kvm_lock_all_vcpus instead of sev's own implementation. Because kvm_lock_all_vcpus uses the _nest_lock feature of lockdep, which ignores subclasses, there is no longer a need to use separate subclasses for source and target VMs. No functional change intended. Suggested-by: Paolo Bonzini Signed-off-by: Maxim Levitsky --- arch/x86/kvm/svm/sev.c | 72 +++--------------------------------------- 1 file changed, 4 insertions(+), 68 deletions(-) diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 0bc708ee2788..16db6179013d 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -1882,70 +1882,6 @@ static void sev_unlock_two_vms(struct kvm *dst_kvm, = struct kvm *src_kvm) atomic_set_release(&src_sev->migration_in_progress, 0); } =20 -/* vCPU mutex subclasses. */ -enum sev_migration_role { - SEV_MIGRATION_SOURCE =3D 0, - SEV_MIGRATION_TARGET, - SEV_NR_MIGRATION_ROLES, -}; - -static int sev_lock_vcpus_for_migration(struct kvm *kvm, - enum sev_migration_role role) -{ - struct kvm_vcpu *vcpu; - unsigned long i, j; - - kvm_for_each_vcpu(i, vcpu, kvm) { - if (mutex_lock_killable_nested(&vcpu->mutex, role)) - goto out_unlock; - -#ifdef CONFIG_PROVE_LOCKING - if (!i) - /* - * Reset the role to one that avoids colliding with - * the role used for the first vcpu mutex. - */ - role =3D SEV_NR_MIGRATION_ROLES; - else - mutex_release(&vcpu->mutex.dep_map, _THIS_IP_); -#endif - } - - return 0; - -out_unlock: - - kvm_for_each_vcpu(j, vcpu, kvm) { - if (i =3D=3D j) - break; - -#ifdef CONFIG_PROVE_LOCKING - if (j) - mutex_acquire(&vcpu->mutex.dep_map, role, 0, _THIS_IP_); -#endif - - mutex_unlock(&vcpu->mutex); - } - return -EINTR; -} - -static void sev_unlock_vcpus_for_migration(struct kvm *kvm) -{ - struct kvm_vcpu *vcpu; - unsigned long i; - bool first =3D true; - - kvm_for_each_vcpu(i, vcpu, kvm) { - if (first) - first =3D false; - else - mutex_acquire(&vcpu->mutex.dep_map, - SEV_NR_MIGRATION_ROLES, 0, _THIS_IP_); - - mutex_unlock(&vcpu->mutex); - } -} - static void sev_migrate_from(struct kvm *dst_kvm, struct kvm *src_kvm) { struct kvm_sev_info *dst =3D to_kvm_sev_info(dst_kvm); @@ -2083,10 +2019,10 @@ int sev_vm_move_enc_context_from(struct kvm *kvm, u= nsigned int source_fd) charged =3D true; } =20 - ret =3D sev_lock_vcpus_for_migration(kvm, SEV_MIGRATION_SOURCE); + ret =3D kvm_lock_all_vcpus(kvm); if (ret) goto out_dst_cgroup; - ret =3D sev_lock_vcpus_for_migration(source_kvm, SEV_MIGRATION_TARGET); + ret =3D kvm_lock_all_vcpus(source_kvm); if (ret) goto out_dst_vcpu; =20 @@ -2100,9 +2036,9 @@ int sev_vm_move_enc_context_from(struct kvm *kvm, uns= igned int source_fd) ret =3D 0; =20 out_source_vcpu: - sev_unlock_vcpus_for_migration(source_kvm); + kvm_unlock_all_vcpus(source_kvm); out_dst_vcpu: - sev_unlock_vcpus_for_migration(kvm); + kvm_unlock_all_vcpus(kvm); out_dst_cgroup: /* Operates on the source on success, on the destination on failure. */ if (charged) --=20 2.46.0