From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id CD0A42AD2E; Wed, 5 Aug 2026 10:52:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785927128; cv=none; b=Yc/UORB48r55JaZtIyD8UGm69xL2e0oBtkII/AGJ7zM30rEJ2K9rKuWNwpOhMSCOJNKfMTwoFte7k4SP+60qE8Sj7xLJ/iyup7NK/13siUpG++dLHUgAvtpr7Mh5mVhMP3djKcsOUJyfJeXQDheGikZ37O08oh1g4k0AdXQ/J0I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785927128; c=relaxed/simple; bh=osqcgEZrB4tIRuddtFyChcekiAZrXeFH6SN6KLCXUeQ=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=AvOsIV7T3at0VUBo9jkuBNMbB5iJeG0y25BvSHOUhJAihdxk+IPMvuc+TPiZAcgZWLMpTliDvNXYGnpczZETQr1VIY5+8eLSNTg6H1wsqe1qoDsdhvhOSqRIwY+M7PvnL84bubsofztc1bpaG2Cxxzqluw2mZXMcxXT0f4FQFWQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=MccCTMFj; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="MccCTMFj" Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5A7A4153B; Wed, 5 Aug 2026 03:52:02 -0700 (PDT) Received: from [10.57.44.180] (unknown [10.57.44.180]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 743203F632; Wed, 5 Aug 2026 03:51:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1785927126; bh=osqcgEZrB4tIRuddtFyChcekiAZrXeFH6SN6KLCXUeQ=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=MccCTMFj2hIMMjW795szcS5FxXktDxGWArGGS9xJv4VDpKX5Fq4pBTHZ+Dqo3dGwn I3za+Zt5GbrL3mgj2p5MRpqTGbT/okZGd5AlVXHozUBVFgINdiUcI9YZ5TtSpFFehy 9K99FQyL3HUPo3MkG8rpZnXuHfDYEsMZGyYwsLhU= Message-ID: Date: Wed, 5 Aug 2026 11:51:55 +0100 Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v9 09/41] KVM: guest_memfd: Filter both shared and private when invalidating Content-Language: en-GB To: ackerleytng@google.com, aik@amd.com, andrew.jones@linux.dev, binbin.wu@linux.intel.com, 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, 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 , Vlastimil Babka Cc: 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 References: <20260728-gmem-inplace-conversion-v9-0-35f9aec2aed2@google.com> <20260728-gmem-inplace-conversion-v9-9-35f9aec2aed2@google.com> From: Suzuki K Poulose In-Reply-To: <20260728-gmem-inplace-conversion-v9-9-35f9aec2aed2@google.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 29/07/2026 01:35, Ackerley Tng via B4 Relay wrote: > From: Ackerley Tng > > Before conversion, a guest_memfd could be either all shared, or all > private, configured at creation time using the INIT_SHARED flag. Hence, > when zapping pages from stage 2 page tables, guest_memfd can filter which > to zap based on the initial shared/private state. > > With conversion, guest_memfd tracks shared/private state on a per-page > level, so a range can contain both private and shared pages. Zap both > private and shared pages for simplicity. > > An alternative would be to iterate guest_memfd attributes and only zap both > if shared and private pages exist within the range. Setting both the shared > and private filters lets the zapping logic do that iteration instead. > > Signed-off-by: Ackerley Tng Reviewed-by: Suzuki K Poulose