From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kent Overstreet Subject: Re: echo dev > /sys/fs/bcache/register gives page allocation failure: order:4, mode:0x2040d0 Date: Mon, 15 Feb 2016 03:11:04 -0900 Message-ID: <20160215121104.GA30514@kmo-pixel> References: <20160215060410.GA30802@merlins.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-pa0-f42.google.com ([209.85.220.42]:35512 "EHLO mail-pa0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752435AbcBOMLI (ORCPT ); Mon, 15 Feb 2016 07:11:08 -0500 Received: by mail-pa0-f42.google.com with SMTP id ho8so86222995pac.2 for ; Mon, 15 Feb 2016 04:11:07 -0800 (PST) Content-Disposition: inline In-Reply-To: <20160215060410.GA30802@merlins.org> Sender: linux-bcache-owner@vger.kernel.org List-Id: linux-bcache@vger.kernel.org To: Marc MERLIN Cc: linux-bcache@vger.kernel.org On Sun, Feb 14, 2016 at 10:04:10PM -0800, Marc MERLIN wrote: > I was able to make one bcache ok, but when trying to make a 2nd one > where I only have a backing device, I'm getting repeated page allocation > failures. > > Just to be clear, this is what I want to do: every new HD backed device > will have bcache on top even if I don't have a cache device for it, so > that I can add bcache later. > Is it something reasonable to do? Setup partitions as bcache backing > devices without a cache device for them? > > So right now, I'm trying to do > md5 - bcache - dmcrypt - btrfs > > So I did > make-bcache -B /dev/md5 > echo /dev/md5 > /sys/fs/bcache/register > > and it fails: > bash: page allocation failure: order:4, mode:0x2040d0 You want CONFIG_COMPACTION=y