From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DC6DDC11F68 for ; Wed, 30 Jun 2021 12:05:40 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 83C4D6161E for ; Wed, 30 Jun 2021 12:05:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 83C4D6161E Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id AE5326B00A3; Wed, 30 Jun 2021 08:05:39 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A95AC6B00A4; Wed, 30 Jun 2021 08:05:39 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 936466B00A5; Wed, 30 Jun 2021 08:05:39 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0179.hostedemail.com [216.40.44.179]) by kanga.kvack.org (Postfix) with ESMTP id 6CFC16B00A3 for ; Wed, 30 Jun 2021 08:05:39 -0400 (EDT) Received: from smtpin30.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 3C18D827CB7E for ; Wed, 30 Jun 2021 12:05:39 +0000 (UTC) X-FDA: 78310260798.30.CD0D15D Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by imf12.hostedemail.com (Postfix) with ESMTP id 6A0EA10000A6 for ; Wed, 30 Jun 2021 12:05:37 +0000 (UTC) Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out2.suse.de (Postfix) with ESMTP id 318BF1FE79; Wed, 30 Jun 2021 12:05:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1625054736; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=t/k459D83dqEBaY9eVSzKip+FmzUX8gzpSpVVytyhG4=; b=eIEBb7gEQPHY6YfiEq0LRY2mB6zcXszr5m324zcFMxb+5I3XEksWKVCXCC3vCTkJidEchM TStrsqir+uxpYPfb0jbCuXsoOsEpK06SkWWJ2eW+z2gQJSkqZ5EywKDlpLtPGLMR4Cctg0 noy1HCiqsrG80dFtzlO/B/h0+3hD8vI= Received: from suse.cz (unknown [10.100.201.86]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by relay2.suse.de (Postfix) with ESMTPS id ED62DA3B8A; Wed, 30 Jun 2021 12:05:35 +0000 (UTC) Date: Wed, 30 Jun 2021 14:05:35 +0200 From: Michal Hocko To: Mel Gorman Cc: Dave Chinner , linux-xfs@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 1/3] mm: Add kvrealloc() Message-ID: References: <20210630061431.1750745-1-david@fromorbit.com> <20210630061431.1750745-2-david@fromorbit.com> <20210630100455.GI3840@techsingularity.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210630100455.GI3840@techsingularity.net> X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 6A0EA10000A6 X-Stat-Signature: woruk4bqensawqsksb4o8p733u9qwjae Authentication-Results: imf12.hostedemail.com; dkim=pass header.d=suse.com header.s=susede1 header.b=eIEBb7gE; dmarc=pass (policy=quarantine) header.from=suse.com; spf=pass (imf12.hostedemail.com: domain of mhocko@suse.com designates 195.135.220.29 as permitted sender) smtp.mailfrom=mhocko@suse.com X-HE-Tag: 1625054737-821429 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed 30-06-21 11:04:55, Mel Gorman wrote: [...] > I didn't do a full audit to determine what fallout, if any, there is > to ultimately passing __GFP_NOFAIL to kvmalloc although kvmalloc_node > explicitly notes that __GFP_NOFAIL is not supported. Adding Michal Hocko > to the cc to see if he remembers why __GFP_NOFAIL was problematic. This is because there are allocations in the vmalloc path which do not get the full gfp context. E.g. page table allocations. This could be likely handled somewhere at the vmalloc layer and retry but I do not remember anybody would be really requesting the support. -- Michal Hocko SUSE Labs