Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id ADD5AC433F5 for ; Tue, 23 Nov 2021 16:36:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235604AbhKWQj6 (ORCPT ); Tue, 23 Nov 2021 11:39:58 -0500 Received: from mail.kernel.org ([198.145.29.99]:45032 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237867AbhKWQjv (ORCPT ); Tue, 23 Nov 2021 11:39:51 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id D033C60FA0; Tue, 23 Nov 2021 16:36:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1637685403; bh=uUIkEweckbYo8Q6YoDffoleSraKp6ilZOhkzhdD8L1A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OrVza2x829sm/EjdHHmq+sgP8SEbBlBlDQNJV12YMQaCArhAz3tF4cYaDLjmfysIP UII/AN10+XB18JIsT2ikqIxOKguY0cg4ncledCkJwX05PjpxyteDvxnp8k5cMWuFB8 5hBZedNv9lJOtJqvU3gTFS3hnuq/fimlcRBCB2SiC1v24bGAFkuWir3Hl9WL3Iiurb cCXJlzY/3fSzmaEoUzM6+rLtimM0j3T974DROPzsSILQGy6JzN06TponjfgwqiDalt r7QDc8AN1t0jCK3ojRqr78paN2yE5GhCXVHF1DCg7uncvb05vd7VU3B2/uF2sNnDV+ MOuUTiLZaTIuA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Vitaly Kuznetsov , Christian Borntraeger , Christian Borntraeger , Paolo Bonzini , Sasha Levin , frankja@linux.ibm.com, hca@linux.ibm.com, gor@linux.ibm.com, kvm@vger.kernel.org, linux-s390@vger.kernel.org Subject: [PATCH MANUALSEL 5.15 5/8] KVM: s390: Cap KVM_CAP_NR_VCPUS by num_online_cpus() Date: Tue, 23 Nov 2021 11:36:27 -0500 Message-Id: <20211123163630.289306-5-sashal@kernel.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20211123163630.289306-1-sashal@kernel.org> References: <20211123163630.289306-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Vitaly Kuznetsov [ Upstream commit 82cc27eff4486f8e79ef8faac1af1f5573039aa4 ] KVM_CAP_NR_VCPUS is a legacy advisory value which on other architectures return num_online_cpus() caped by KVM_CAP_NR_VCPUS or something else (ppc and arm64 are special cases). On s390, KVM_CAP_NR_VCPUS returns the same as KVM_CAP_MAX_VCPUS and this may turn out to be a bad 'advice'. Switch s390 to returning caped num_online_cpus() too. Acked-by: Christian Borntraeger Signed-off-by: Vitaly Kuznetsov Reviewed-by: Christian Borntraeger Message-Id: <20211116163443.88707-6-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini Signed-off-by: Sasha Levin --- arch/s390/kvm/kvm-s390.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 1c97493d21e10..31bf4bc5a23d7 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -585,6 +585,8 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) r = KVM_MAX_VCPUS; else if (sclp.has_esca && sclp.has_64bscao) r = KVM_S390_ESCA_CPU_SLOTS; + if (ext == KVM_CAP_NR_VCPUS) + r = min_t(unsigned int, num_online_cpus(), r); break; case KVM_CAP_S390_COW: r = MACHINE_HAS_ESOP; -- 2.33.0