From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (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 E6A0A2DC765; Tue, 16 Sep 2025 02:00:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.50.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757988034; cv=none; b=eQE6CQcDTgwbCmHyKb/oqCyPWlVCMYmSKT0nUlMy5CjDicKleyWhEWevE+p0IjtGsDWnJvT060HqunkQXeyd4QKGpR75xmrJ7Gd1vQzgQxVGR9MYvDeinsInG3J1KoPIEJLe51BZ3H9QgPcfZGMx9K5iKot9x2V1yJD5vxFCNhU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757988034; c=relaxed/simple; bh=dEAGRAtP8MWvQ01ZcTojl+58fTwwxUGVRfZ5aVBkcYQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=CdVmyz27IW1J8nyphTEX73BgGaHo5eUGBE0Ms0fTKNKtQXSYspuYjvJxYoN3UZcXQAsmrBeKN+mfg+hs6Nb1f5FiBm/a9aLiS06PSFMFoh5Cm7S3dRoBECYNrqZCex4cIIfg9CDdh0senOKgpSk6AK/OseRydYSASGTuf6TE4M4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=Fs8qO5nX; arc=none smtp.client-ip=90.155.50.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="Fs8qO5nX" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=1vLbiGQX0AC9H7KluJOU/q9glSrJZnzHnZoclCwUWks=; b=Fs8qO5nXlZ6sLXrQWKCVDzYpAb D8rXf2rGYfMLMaQ/39ZY+LeLb8A5U3uUT63WR2SwmCRc5OjcXtuiH9o6Q5heD/6OTRRSybgaSeXcm UdPI0elIYFXp4LNQNDiQwn9HKkNmdylzrAf7huSt712ThMHxInXeNNrcdrCC+MdkO++mCoFLjkLvr XXPtwewEvN3slr+xBJltB7k8btx2kgWhOcdRrQ5fyyfmSVjFws7nmbW/jVZzalMG5+BrTMvIzF39O VurlrYO7JWMpan+hRPOqON+fROn/mOP0ctcNs5l2OJRtniph+xYhlObgtQCaxN8KHHZ9cNGvnpMZr lNZBXHAw==; Received: from willy by casper.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1uyKzX-0000000BcoG-1EAX; Tue, 16 Sep 2025 02:00:23 +0000 Date: Tue, 16 Sep 2025 03:00:23 +0100 From: Matthew Wilcox To: "Kalyazin, Nikita" Cc: "akpm@linux-foundation.org" , "david@redhat.com" , "pbonzini@redhat.com" , "seanjc@google.com" , "viro@zeniv.linux.org.uk" , "brauner@kernel.org" , "peterx@redhat.com" , "lorenzo.stoakes@oracle.com" , "Liam.Howlett@oracle.com" , "vbabka@suse.cz" , "rppt@kernel.org" , "surenb@google.com" , "mhocko@suse.com" , "jack@suse.cz" , "linux-mm@kvack.org" , "kvm@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-fsdevel@vger.kernel.org" , "jthoughton@google.com" , "tabba@google.com" , "vannapurve@google.com" , "Roy, Patrick" , "Thomson, Jack" , "Manwaring, Derek" , "Cali, Marco" Subject: Re: [RFC PATCH v6 1/2] mm: guestmem: introduce guestmem library Message-ID: References: <20250915161815.40729-1-kalyazin@amazon.com> <20250915161815.40729-2-kalyazin@amazon.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250915161815.40729-2-kalyazin@amazon.com> On Mon, Sep 15, 2025 at 04:18:27PM +0000, Kalyazin, Nikita wrote: > From: Nikita Kalyazin > > Move MM-generic parts of guest_memfd from KVM to MM. This allows other > hypervisors to use guestmem code and enables UserfaultFD implementation > for guest_memfd [1]. Previously it was not possible because KVM (and > guest_memfd code) might be built as a module. https://lore.kernel.org/kvm/Z0DOdTRAaK3whZKW@casper.infradead.org/ remains un-addressed. ie this entire approach is garbage. throw it away and start again.