From mboxrd@z Thu Jan 1 00:00:00 1970 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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E32B8D3E797 for ; Thu, 11 Dec 2025 06:56:45 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vTab7-000871-09; Thu, 11 Dec 2025 01:56:21 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vTab5-00085d-38 for qemu-devel@nongnu.org; Thu, 11 Dec 2025 01:56:19 -0500 Received: from mgamail.intel.com ([192.198.163.8]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vTab3-0002r2-FA for qemu-devel@nongnu.org; Thu, 11 Dec 2025 01:56:18 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1765436177; x=1796972177; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=hwV6SO4dnMAkdF+7KToIlu3XTOdCNR+uEY9rLZTHs4I=; b=nLD1ZtTxJtgwxEB5d6Ty/rhid+gaqWabpDNvFXWdzwkTCWuPKJ9F6O6t n+982KuI6MAfU1upJsxkPOwg1cE4FujumHoRfPlalOCNPEhQse8mCRjEF seXrbn6ONeAFud1AbvrXFlJNPsnHwvQGv/FfELKwz76tVplswgZP1qdAC 0lBl/hccjXRkxdowMRs/OD6CVfNPhtrFGWo1CNT2sG3uMU4addCkOXiaO i+sWd+PGgMgUMDFPvuS6TLl6sYd85GwzoFb99XjApq+S660Dg/A/cjlkX JFIVJnsdTvnPM4yPdAcp3u0crWbTFAwGMRRD4/aa8jz3N/EGIOZbuhbSA g==; X-CSE-ConnectionGUID: y6QNUm9QQLmHWvHINvh6yw== X-CSE-MsgGUID: VThL5qrvQJKOjcc7cbxD3Q== X-IronPort-AV: E=McAfee;i="6800,10657,11638"; a="85021699" X-IronPort-AV: E=Sophos;i="6.20,265,1758610800"; d="scan'208";a="85021699" Received: from orviesa005.jf.intel.com ([10.64.159.145]) by fmvoesa102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Dec 2025 22:56:15 -0800 X-CSE-ConnectionGUID: mZSZsQsjSzKoBkMpL8jNgw== X-CSE-MsgGUID: 3RnaMyYzSc60hNi/p896Ww== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.20,265,1758610800"; d="scan'208";a="201817078" Received: from xiaoyaol-hp-g830.ccr.corp.intel.com (HELO [10.124.240.173]) ([10.124.240.173]) by orviesa005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Dec 2025 22:56:13 -0800 Message-ID: <1f119eca-d3c0-4b32-9c37-c82921245d6d@intel.com> Date: Thu, 11 Dec 2025 14:56:09 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 2/9] kvm: Detect guest-memfd flags supported To: Peter Xu , qemu-devel@nongnu.org Cc: Paolo Bonzini , David Hildenbrand , Alexey Kardashevskiy , Chenyi Qiang , Juraj Marcin , Fabiano Rosas References: <20251119172913.577392-1-peterx@redhat.com> <20251119172913.577392-3-peterx@redhat.com> Content-Language: en-US From: Xiaoyao Li In-Reply-To: <20251119172913.577392-3-peterx@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=192.198.163.8; envelope-from=xiaoyao.li@intel.com; helo=mgamail.intel.com X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, HK_RANDOM_ENVFROM=0.001, HK_RANDOM_FROM=0.001, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On 11/20/2025 1:29 AM, Peter Xu wrote: > Detect supported guest-memfd flags by the current kernel, and reject > creations of guest-memfd using invalid flags. When the cap isn't > available, then no flag is supported. > > Signed-off-by: Peter Xu Reviewed-by: Xiaoyao Li > --- > accel/kvm/kvm-all.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c > index 96c194ce54..f477014126 100644 > --- a/accel/kvm/kvm-all.c > +++ b/accel/kvm/kvm-all.c > @@ -108,6 +108,7 @@ static int kvm_sstep_flags; > static bool kvm_immediate_exit; > static uint64_t kvm_supported_memory_attributes; > static bool kvm_guest_memfd_supported; > +static uint64_t kvm_guest_memfd_flags_supported; > static hwaddr kvm_max_slot_size = ~0; > > static const KVMCapabilityInfo kvm_required_capabilites[] = { > @@ -2787,6 +2788,10 @@ static int kvm_init(AccelState *as, MachineState *ms) > kvm_guest_memfd_supported = > kvm_vm_check_extension(s, KVM_CAP_GUEST_MEMFD) && > kvm_vm_check_extension(s, KVM_CAP_USER_MEMORY2); > + > + ret = kvm_vm_check_extension(s, KVM_CAP_GUEST_MEMFD_FLAGS); > + kvm_guest_memfd_flags_supported = ret > 0 ? ret : 0; > + > kvm_pre_fault_memory_supported = kvm_vm_check_extension(s, KVM_CAP_PRE_FAULT_MEMORY); > > if (s->kernel_irqchip_split == ON_OFF_AUTO_AUTO) { > @@ -4492,6 +4497,12 @@ int kvm_create_guest_memfd(uint64_t size, uint64_t flags, Error **errp) > return -1; > } > > + if (flags & ~kvm_guest_memfd_flags_supported) { > + error_setg(errp, "KVM does not support guest-memfd flag: 0x%"PRIx64, > + flags & ~kvm_guest_memfd_flags_supported); > + return -1; > + } > + > fd = kvm_vm_ioctl(kvm_state, KVM_CREATE_GUEST_MEMFD, &guest_memfd); > if (fd < 0) { > error_setg_errno(errp, errno, "Error creating KVM guest_memfd");