From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 BF0A98BFF for ; Sun, 8 Jun 2025 23:42:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749426165; cv=none; b=TFNlxXbKGFiTWT8m9MnCLswc8P5lB3xqL2R2KHGa/svVJlVflopIDzm5NdWYHZm5p8VmWSgm/p7/z89+TForPY4+dI4bEDbf/kgK6FBV/4LGg2Uz7cHh0a+BdogzsP5+62qGp+TapiwF4w8wt6Mv3ZJzThqOsnjGpc+M0B0uZC8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749426165; c=relaxed/simple; bh=3BrPqick3GI480dewMt6lfWOE6CKi6PdWbeMGGqvCn8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Z6N/0R5O9Gfo+RP5GY6sHa3u1HYGEwfnKvZjXhQ9XMsa7lZjEmy7Ydi4R/zH6N1hCv4KnZXGRIEamCmmyRXcV8ylcHJJrrjAzqCivbJOmpd1qcvhaSci6UjtjahMakvzgeHAqH4h8uXMDM1q0TgKXwVnPI2wa+NyEuzfZ2PqsPc= 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=XEAdgQ0Y; arc=none smtp.client-ip=170.10.129.124 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="XEAdgQ0Y" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1749426162; h=from:from: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:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=BrhPYURkD84ucWukiI2OFvciF9PKhh9wNSV3UCxvffw=; b=XEAdgQ0Yd7sLbdcoPj59BFQOyjwPtdJibsFCaYF4X2/VGmGMc6AqEVme0+eVB6LxvFFndR jxROxGMxY1gn7o4zjJCZ7+nPBJYieHKJRZFswfPjRTRhoAuvhldeMiAic86pKWCd+2qEd0 rHhipB4eUwTbha9bkR6N91pIAvGXiX8= Received: from mail-pl1-f198.google.com (mail-pl1-f198.google.com [209.85.214.198]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-479-2vC9Y-o6Mv-h_1-PQ1fEjw-1; Sun, 08 Jun 2025 19:42:41 -0400 X-MC-Unique: 2vC9Y-o6Mv-h_1-PQ1fEjw-1 X-Mimecast-MFC-AGG-ID: 2vC9Y-o6Mv-h_1-PQ1fEjw_1749426160 Received: by mail-pl1-f198.google.com with SMTP id d9443c01a7336-23536f7c2d7so58261975ad.2 for ; Sun, 08 Jun 2025 16:42:41 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1749426160; x=1750030960; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=BrhPYURkD84ucWukiI2OFvciF9PKhh9wNSV3UCxvffw=; b=KUlq5i/ArXf4gcZDLoFXEWPu5TxUxz8P4zIFbv50RFsjMl2/eQrONYj+14oZuy4pgI MaABeZCzFqTzTaM51+qpYbg/Yn0DETYioblBgOsPOIFsokp47k5B3WGZWVO7+SzXTYJZ 8gprwPIgF8BXc9pNoeF7NTz9h0WflQhE+zhHy7UTE/X8bO9Y9JBYRS9AIxunII9mxPsS 6cdGiY3R/9dKGinhF7wWGk+dRQ5m2CWRN3HfN9yQjraEEyo9gd572Z6gFJ05pCwu0mSx JLvNFXC+/OPuE560ME4luaGS2fnERDpxAxXwI3pmDIWj+zCoDYXIxLg5l207wTgqEtNM hP/Q== X-Forwarded-Encrypted: i=1; AJvYcCUyQ3q0+7kGDOYSRfNOytAFC2Zz5SC3rmqef4z1HhZzphkrpMVlpGslTQDdDN2MUwLUBbU=@vger.kernel.org X-Gm-Message-State: AOJu0YxFpNL78QhEhbZVY/EPvKceujjTtzSokob4slCFId49a7snx9r5 E4znDfXtrK8mIVXUFePhENRn57WEEFQ8xcuZzwd+FA6SL92A3IEEA3nPz4CsQhQ38+VQp2v6IpQ vf2ViF5J/ow3EnR2Wf97IGnAFChosz/bCBK7xx7idqPv6xOC4NmkJaw== X-Gm-Gg: ASbGncudu4p+oO/5DccB+pm3LFQNEK90MgWen9Jjzysnt/6ll2GhBGzFBNAo9JCs/UB wCacdG8yPCuH9Klofn6f+Yz2bX2o3nG34qCjeunN3wGIUulokGtDsNmiprcTdYEOuchhLDieQDV bymx0vAzaS5U0LTqsIokoCO4Wis4NiUFZLJAhZLuMiks/WWpBTYMdKVgBjc6QRQ99IrpS4vu0RP R8aSdeSW6TgVhg3KuSy41D8OKpl50GKybk9dYqUiGlxKNQFBOUUGQFazWX483s6197BVhbRXX8F QGG1MGt0R3tQqAjZgl1mJnoZdRxlinu5RVt96yG7Qg7A27grnPoSU0+BV2SjJQ== X-Received: by 2002:a17:902:d483:b0:235:e1d6:4e29 with SMTP id d9443c01a7336-23601dc0136mr171113795ad.36.1749426160466; Sun, 08 Jun 2025 16:42:40 -0700 (PDT) X-Google-Smtp-Source: AGHT+IFhhqD14zLILdtjSL+nHgtl9T+hPRFKWMZ0ZPJay0gEN8OyStVlbzILHd0cwkG13OOqkgTWcw== X-Received: by 2002:a17:902:d483:b0:235:e1d6:4e29 with SMTP id d9443c01a7336-23601dc0136mr171113545ad.36.1749426160106; Sun, 08 Jun 2025 16:42:40 -0700 (PDT) Received: from [192.168.68.51] (n175-34-62-5.mrk21.qld.optusnet.com.au. [175.34.62.5]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-236032fceb2sm43669945ad.96.2025.06.08.16.42.19 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 08 Jun 2025 16:42:39 -0700 (PDT) Message-ID: Date: Mon, 9 Jun 2025 09:42:17 +1000 Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v11 08/18] KVM: guest_memfd: Allow host to map guest_memfd pages To: Fuad Tabba , kvm@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-mm@kvack.org, kvmarm@lists.linux.dev Cc: pbonzini@redhat.com, chenhuacai@kernel.org, mpe@ellerman.id.au, anup@brainfault.org, paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu, seanjc@google.com, viro@zeniv.linux.org.uk, brauner@kernel.org, willy@infradead.org, akpm@linux-foundation.org, xiaoyao.li@intel.com, yilun.xu@intel.com, chao.p.peng@linux.intel.com, jarkko@kernel.org, amoorthy@google.com, dmatlack@google.com, isaku.yamahata@intel.com, mic@digikod.net, vbabka@suse.cz, vannapurve@google.com, ackerleytng@google.com, mail@maciej.szmigiero.name, david@redhat.com, michael.roth@amd.com, wei.w.wang@intel.com, liam.merwick@oracle.com, isaku.yamahata@gmail.com, kirill.shutemov@linux.intel.com, suzuki.poulose@arm.com, steven.price@arm.com, quic_eberman@quicinc.com, quic_mnalajal@quicinc.com, quic_tsoni@quicinc.com, quic_svaddagi@quicinc.com, quic_cvanscha@quicinc.com, quic_pderrin@quicinc.com, quic_pheragu@quicinc.com, catalin.marinas@arm.com, james.morse@arm.com, yuzenghui@huawei.com, oliver.upton@linux.dev, maz@kernel.org, will@kernel.org, qperret@google.com, keirf@google.com, roypat@amazon.co.uk, shuah@kernel.org, hch@infradead.org, jgg@nvidia.com, rientjes@google.com, jhubbard@nvidia.com, fvdl@google.com, hughd@google.com, jthoughton@google.com, peterx@redhat.com, pankaj.gupta@amd.com, ira.weiny@intel.com References: <20250605153800.557144-1-tabba@google.com> <20250605153800.557144-9-tabba@google.com> Content-Language: en-US From: Gavin Shan In-Reply-To: <20250605153800.557144-9-tabba@google.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 6/6/25 1:37 AM, Fuad Tabba wrote: > This patch enables support for shared memory in guest_memfd, including > mapping that memory from host userspace. > > This functionality is gated by the KVM_GMEM_SHARED_MEM Kconfig option, > and enabled for a given instance by the GUEST_MEMFD_FLAG_SUPPORT_SHARED > flag at creation time. > > Co-developed-by: Ackerley Tng > Signed-off-by: Ackerley Tng > Signed-off-by: Fuad Tabba > --- > include/linux/kvm_host.h | 13 +++++++ > include/uapi/linux/kvm.h | 1 + > virt/kvm/Kconfig | 4 +++ > virt/kvm/guest_memfd.c | 76 ++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 94 insertions(+) > Reviewed-by: Gavin Shan