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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 041DCC433EF for ; Mon, 6 Sep 2021 08:40:04 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 89FE660E94 for ; Mon, 6 Sep 2021 08:40:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 89FE660E94 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id D14746B0072; Mon, 6 Sep 2021 04:40:02 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id CC3D86B0073; Mon, 6 Sep 2021 04:40:02 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BB3CA6B0074; Mon, 6 Sep 2021 04:40:02 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0069.hostedemail.com [216.40.44.69]) by kanga.kvack.org (Postfix) with ESMTP id A76006B0072 for ; Mon, 6 Sep 2021 04:40:02 -0400 (EDT) Received: from smtpin04.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 31CEC1814C6FC for ; Mon, 6 Sep 2021 08:40:02 +0000 (UTC) X-FDA: 78556501044.04.116ADBA Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf16.hostedemail.com (Postfix) with ESMTP id E0625F000090 for ; Mon, 6 Sep 2021 08:40:01 +0000 (UTC) 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=xT814fvWWw70J/M6nc8pISxm2/K29BOxkkAtfEmol6A=; b=aWOWFIKoKbEgpB/11WlRhs7NYQ FgHMpo+La1rd1IhbdPsSy/ThFnQ/LzZgp4+2DE4dokxiyX1VEEPq/LrmKsaZ371Kj8LKQCt1j9Fkb tFN323ZT8xcO+nUSRCzetUgtXrwKhZ6AzYoGAdCtBbR5GiGQUFqF10FEKEjQh7wlD1XfXwxCPZfHH u1wPRd4/b/LEMImjLvUaPxq8i9T1FFpiXan04sT/OA3eq4vUHNsT0ANcgfA9cD/Y7oNQWl6OF9BA4 HQg4qk+Honk7uK2k/Ob2CC0ljaEka/p30fhfFY9nTz/EPS3X9dKD889DVyJVGhL0iSEsVaYAsfRXT 23jHhYQQ==; Received: from hch by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1mNA8x-006mhR-5b; Mon, 06 Sep 2021 08:38:57 +0000 Date: Mon, 6 Sep 2021 09:38:19 +0100 From: Christoph Hellwig To: Jaewon Kim Cc: minchan@kernel.org, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, ytk.lee@samsung.com, jaewon31.kim@gmail.com Subject: Re: [PATCH] zram_drv: allow reclaim on bio_alloc Message-ID: References: <20210906052926.6007-1-jaewon31.kim@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210906052926.6007-1-jaewon31.kim@samsung.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html X-Rspamd-Queue-Id: E0625F000090 Authentication-Results: imf16.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=aWOWFIKo; dmarc=none; spf=none (imf16.hostedemail.com: domain of BATV@casper.srs.infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=BATV@casper.srs.infradead.org X-Rspamd-Server: rspam01 X-Stat-Signature: 6y7qe66wmwphi1hgq17mjc363q9es7kt X-HE-Tag: 1630917601-157229 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 Mon, Sep 06, 2021 at 02:29:26PM +0900, Jaewon Kim wrote: > The read_from_bdev_async is not called on atomic context. So GFP_NOIO is > available rather than GFP_ATOMIC. If there were reclaimable pages with > GFP_NOIO, we can avoid allocation failure and page fault failure. > > Reported-by: Yong-Taek Lee > Signed-off-by: Jaewon Kim > --- > drivers/block/zram/zram_drv.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c > index fcaf2750f68f..53be528a39a2 100644 > --- a/drivers/block/zram/zram_drv.c > +++ b/drivers/block/zram/zram_drv.c > @@ -587,7 +587,7 @@ static int read_from_bdev_async(struct zram *zram, struct bio_vec *bvec, > { > struct bio *bio; > > - bio = bio_alloc(GFP_ATOMIC, 1); > + bio = bio_alloc(GFP_NOIO|__GFP_HIGHMEM, 1); Passing __GFP_HIGHMEM to bio_alloc does not make any sense whatsoever.