From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.11]) (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 40245371CFF; Fri, 14 Aug 2026 06:36:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786689392; cv=none; b=hYUXV5rO1WxmRwpd4lHQ+44s54eMrRf8eucFwhRFFPgSpWpuj1ATBFeaz8b5xtuP/xBK2yGDQF1biB+FGT9ItD2GuFfh1OmLAw3HD9tG9rQ/H1aZwNW4Wtx0SilLaKLmncwVyAF39WHQfgNqZud2fc++I3Gx9eisFfRsnW096co= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786689392; c=relaxed/simple; bh=QS50L3Ej/o3Eh9pAbeQ2YK77qR7pbIzS03/vLRtWg60=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=XHw0AyAtspaGxr6LdifEnXUxxw0ux9Q15mSftvOA+vBk84kwXyHIJ3m0Y/5sy2VvR/FoiYmdlNMs4BC9IfRGLeFYeQk4maFkKSafpm0qCLsCNzQC4ifxsNonbWpmT5QT9Oh86EW+ms2lpWKxrK1yULuXjo+WaiZkTVPOZRFEcIw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=EXnO4n68; arc=none smtp.client-ip=192.198.163.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="EXnO4n68" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1786689390; x=1818225390; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=QS50L3Ej/o3Eh9pAbeQ2YK77qR7pbIzS03/vLRtWg60=; b=EXnO4n680GlEtZhSRJjvjCapi9SVIXyQpIvY4A75L3/urY1Ktyp+5/ZH Va9m0TBtncGDJ5aB8Mma8/CMWbY2i9zTqlDqIWegmV9iSDAdK4YXrMQbQ BmsFez3bjjWEtpXN3LgT/Vv9MitasUkdGgR6R/jwCvz9np5mgUXIeQpgF ujxyfcD1WZfzOtIggCLVd1+pZqTmYhr17a+1LG8hyfIvTfmTNhkmVI/Pe OGG2/GBNXuizUPGDfrzv5182VXqQr7yUdRECR4gqiG7jcQBr8b1PYdaYx MZczLFuz5HUfottjbEQLrUMcAlFJqq7qmM3kqTaNZppq4s1J1ifqeaEu9 Q==; X-CSE-ConnectionGUID: TnO7V0sESXK3G9nTYqkGew== X-CSE-MsgGUID: h/vRWQyvT4WwVQyNliqEbw== X-IronPort-AV: E=McAfee;i="6800,10657,11874"; a="97859361" X-IronPort-AV: E=Sophos;i="6.25,222,1779174000"; d="scan'208";a="97859361" Received: from fmviesa001.fm.intel.com ([10.60.135.141]) by fmvoesa105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Aug 2026 23:36:29 -0700 X-CSE-ConnectionGUID: GUn57tdyTJmSCwMdue8GsA== X-CSE-MsgGUID: wgv+28R0Spi44YdDQh7WUQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,222,1779174000"; d="scan'208";a="288935132" Received: from binbinwu-mobl.ccr.corp.intel.com (HELO [10.124.245.162]) ([10.124.245.162]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Aug 2026 23:36:15 -0700 Message-ID: <658c8441-972a-4298-a4b2-8ec4f2ca338a@linux.intel.com> Date: Fri, 14 Aug 2026 14:36:13 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v10 21/41] KVM: guest_memfd: Enable INIT_SHARED on guest_memfd for x86 Coco VMs To: ackerleytng@google.com Cc: aik@amd.com, andrew.jones@linux.dev, brauner@kernel.org, chao.p.peng@linux.intel.com, david@kernel.org, jmattson@google.com, jthoughton@google.com, michael.roth@amd.com, oupton@kernel.org, pankaj.gupta@amd.com, qperret@google.com, rick.p.edgecombe@intel.com, rientjes@google.com, shivankg@amd.com, steven.price@arm.com, tabba@google.com, willy@infradead.org, wyihan@google.com, yan.y.zhao@intel.com, forkloop@google.com, pratyush@kernel.org, suzuki.poulose@arm.com, aneesh.kumar@kernel.org, liam@infradead.org, Paolo Bonzini , Sean Christopherson , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Jonathan Corbet , Shuah Khan , Shuah Khan , Vishal Annapurve , Andrew Morton , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Youngjun Park , Qi Zheng , Shakeel Butt , Kiryl Shutsemau , Baoquan He , Jason Gunthorpe , John Hubbard , Peter Xu , tarunsahu@google.com, Vlastimil Babka , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, linux-coco@lists.linux.dev, Xiaoyao Li References: <20260807-gmem-inplace-conversion-v10-0-2fc18ee6d3ba@google.com> <20260807-gmem-inplace-conversion-v10-21-2fc18ee6d3ba@google.com> Content-Language: en-US From: Binbin Wu In-Reply-To: <20260807-gmem-inplace-conversion-v10-21-2fc18ee6d3ba@google.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/8/2026 5:53 AM, Ackerley Tng via B4 Relay wrote: > From: Sean Christopherson > > Now that guest_memfd supports tracking private vs. shared within gmem > itself, allow userspace to specify INIT_SHARED on a guest_memfd instance > for x86 Confidential Computing (CoCo) VMs, so long as in-place conversion > is enabled, i.e. when it's actually possible for a guest_memfd instance to > contain shared memory. > > Signed-off-by: Sean Christopherson > Reviewed-by: Fuad Tabba > Reviewed-by: Xiaoyao Li > Tested-by: Shivank Garg > Signed-off-by: Ackerley Tng Reviewed-by: Binbin Wu