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 A3A1F12B63; Thu, 7 Nov 2024 15:10:14 +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=1730992216; cv=none; b=FTHZ7lg7LDu/ENe3v7PmB0O/yP+DHcvTtu4M9rsWltYa/RkIprtfuFTk8HGoK0s55GCgh3bUV+YUUMC/Py0SjW8i2JAZ9ZiQFgRM3q5TYIXERJf5vGRuM2s9K/Yi9sTwSFI4Fi80eHSRmdwGZnT9ESsvZ7xU1/Al+Ae9YQwD0gw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730992216; c=relaxed/simple; bh=dF5XVTxIII6iMggWIEemDLIC7Cxe07E6GULEaQ+Lc60=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=eQndNuMuedmJb3dtHuc5qNGRgVUZQgieh2pbZil1a3vCBve3TYcpocqTzhLIub8j+9w12MGcdbLQuiYo404AhihM7qTlwwZeR/Iw++bnrr3jAKd2ypu8twMjrR5qfklDq5ll4OP8idqbvUGpBLVvfzBRjuY6qNqe86TL4YmSxkw= 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=GuCmWcel; 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="GuCmWcel" 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=Vom1WJYdLvjku2r/Xl0EhIhQ5E31YZkW3BtO+U5Dsek=; b=GuCmWcelHu3QNDVTgzwIceTERX /vZoa+fZx0pT+5jVIJzTCv4ZeGycAXKZ3WwH8ZIMz+UT6M09CyrfQf1dpKHT0h9TQDt7wIIwZFQMR jqTi79AogfM+fEMudUmIdznL/18LTQnR5GyxB3te8KLOPk2/tBUc41LuSKeak40E/SdOtz73JCu6G XqwMJZZPYY+Ahs8ZDynRIykD5DX82jInNorF8DV35Rroz+gdSejfsjnLsw+r9X9jP0LPRRRbCHyyU BTuDrcnLXh+iFBOFnLbAulo4+xDfmkRer56WnCT4YEvMuRMroRNIuix2qLa2bU/s9nzQ0smuqQsK9 dgIZeC2Q==; Received: from willy by casper.infradead.org with local (Exim 4.98 #2 (Red Hat Linux)) id 1t949B-00000006rdv-0Z6w; Thu, 07 Nov 2024 15:10:09 +0000 Date: Thu, 7 Nov 2024 15:10:08 +0000 From: Matthew Wilcox To: Shivank Garg Cc: x86@kernel.org, viro@zeniv.linux.org.uk, brauner@kernel.org, jack@suse.cz, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-api@vger.kernel.org, linux-arch@vger.kernel.org, kvm@vger.kernel.org, chao.gao@intel.com, pgonda@google.com, thomas.lendacky@amd.com, seanjc@google.com, luto@kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, arnd@arndb.de, pbonzini@redhat.com, kees@kernel.org, bharata@amd.com, nikunj@amd.com, michael.day@amd.com, Neeraj.Upadhyay@amd.com, linux-coco@lists.linux.dev Subject: Re: [RFC PATCH 0/4] Add fbind() and NUMA mempolicy support for KVM guest_memfd Message-ID: References: <20241105164549.154700-1-shivankg@amd.com> <6004eaa4-934c-48f4-b502-cf7e436462fc@amd.com> Precedence: bulk X-Mailing-List: linux-api@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: <6004eaa4-934c-48f4-b502-cf7e436462fc@amd.com> On Thu, Nov 07, 2024 at 02:24:20PM +0530, Shivank Garg wrote: > The folio allocation path from guest_memfd typically looks like this... > > kvm_gmem_get_folio > filemap_grab_folio > __filemap_get_folio > filemap_alloc_folio > __folio_alloc_node_noprof > -> goes to the buddy allocator > > Hence, I am trying to have a version of filemap_alloc_folio() that takes an mpol. It only takes that path if cpuset_do_page_mem_spread() is true. Is the real problem that you're trying to solve that cpusets are being used incorrectly? Backing up, it seems like you want to make a change to the page cache, you've had a long discussion with people who aren't the page cache maintainer, and you all understand the pros and cons of everything, and here you are dumping a solution on me without talking to me, even though I was at Plumbers, you didn't find me to tell me I needed to go to your talk. So you haven't explained a damned thing to me, and I'm annoyed at you. Do better. Starting with your cover letter.