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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 08E5AC433FE for ; Wed, 23 Mar 2022 00:25:03 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 3E7206B0072; Tue, 22 Mar 2022 20:25:03 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 3701A6B0073; Tue, 22 Mar 2022 20:25:03 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 25D6F6B0074; Tue, 22 Mar 2022 20:25:03 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0053.hostedemail.com [216.40.44.53]) by kanga.kvack.org (Postfix) with ESMTP id 129D36B0072 for ; Tue, 22 Mar 2022 20:25:03 -0400 (EDT) Received: from smtpin20.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id B289D8249980 for ; Wed, 23 Mar 2022 00:25:02 +0000 (UTC) X-FDA: 79273756044.20.82972BE Received: from mail-pg1-f171.google.com (mail-pg1-f171.google.com [209.85.215.171]) by imf26.hostedemail.com (Postfix) with ESMTP id 2C890140035 for ; Wed, 23 Mar 2022 00:25:02 +0000 (UTC) Received: by mail-pg1-f171.google.com with SMTP id s72so11071489pgc.5 for ; Tue, 22 Mar 2022 17:25:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=R+KjN3V1SlenXxLe5Smnpn6Kl0EaEBKZxKusql1w254=; b=cvECYKNH5pjdsTN/s4iB+l7+gDkakGP7uIYy2JGzTxtG2ATo9nLBii0ZdatESkWG3r xpu9zPFmFQIcFc2NgGPRDHqFw286JKtjV4porAqlXMNXwjp3taEqGJGgENu7mlpc7UJE pz91lVnxkYRu1p+b95nNx2EkIDcRYKEaNTHEM8Zaf8Gq+Dc4UhOutT/roPqH2cmF75JV c59rhnnyv/iSyQKaM8GMVvYIYNFsEZPjLnyZ3Ca2c/1wZbRaJpD9NsfnJJ0BMz1IJ0oa bBsifDdmeE2f7E99dKbDCRH03P1IbvTt4/rnGec8PnA+0KqtLa7vmz4O42hF6kN3ebm5 KOUQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=R+KjN3V1SlenXxLe5Smnpn6Kl0EaEBKZxKusql1w254=; b=Fks2e+IRoEGUDtbIZhZm8zda+9iSEjnfTzriFdebsyRKm8DwZ0+QJDFubYHkdHfT4U 5H3l8ItAFKBL+4P55zgOSa1m0frr0HZLH2mm0ej2Sui4krf+0PuOhBA4GhvKQpzjGDjr gBJ0kiPaV669g2qdAjiecmEXvOSP6ZkeIh26/SuRX0gK+cWGPmDVu2yyoSNXtmEorsLC MvQy7tjWSaG7kr/6XYwd1G667Zu9RNzhGh9yuPXlhswaNh3/HcONzH//T/0HuTHy0BsI B9ODaN3JgQwKqxqDivcT7GMdcKjLQq5sV5tWC9APp7Yp7AtMqJ4/J5HxjHLhvay7RK90 WT6Q== X-Gm-Message-State: AOAM532Jrvx8cF6cbM1hmsCqUpPuC6yfZHANYWadPUUYNxJUQh/bp2wB xFzqJ5C1tY7ZOozfGabO+yc= X-Google-Smtp-Source: ABdhPJzCZi/vmJnOJ2M5f5b9fWl00X7eHUop/OzzdFXBsx9usW96xIqvw/d6pRX/L31s2XfkT3Y6nQ== X-Received: by 2002:a63:194e:0:b0:372:c757:c569 with SMTP id 14-20020a63194e000000b00372c757c569mr23701978pgz.516.1647995101156; Tue, 22 Mar 2022 17:25:01 -0700 (PDT) Received: from google.com ([2620:15c:211:201:3d69:cefc:7302:2e52]) by smtp.gmail.com with ESMTPSA id n14-20020a17090a394e00b001c670d67b8esm3968381pjf.32.2022.03.22.17.24.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 22 Mar 2022 17:25:00 -0700 (PDT) Date: Tue, 22 Mar 2022 17:24:58 -0700 From: Minchan Kim To: Andrew Morton Cc: vbabka@suse.cz, surenb@google.com, stable@vger.kernel.org, sfr@canb.auug.org.au, rientjes@google.com, nadav.amit@gmail.com, mhocko@suse.com, quic_charante@quicinc.com, patches@lists.linux.dev, linux-mm@kvack.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org Subject: Re: [patch 163/227] mm: madvise: skip unmapped vma holes passed to process_madvise Message-ID: References: <20220322143803.04a5e59a07e48284f196a2f9@linux-foundation.org> <20220322214648.AB7A1C340EC@smtp.kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220322214648.AB7A1C340EC@smtp.kernel.org> X-Rspamd-Server: rspam09 X-Rspam-User: X-Stat-Signature: zykrwghdmshzaci5w7i8isu13484j9m4 Authentication-Results: imf26.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=cvECYKNH; dmarc=fail reason="SPF not aligned (relaxed), DKIM not aligned (relaxed)" header.from=kernel.org (policy=none); spf=pass (imf26.hostedemail.com: domain of minchan.kim@gmail.com designates 209.85.215.171 as permitted sender) smtp.mailfrom=minchan.kim@gmail.com X-Rspamd-Queue-Id: 2C890140035 X-HE-Tag: 1647995102-275728 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 Tue, Mar 22, 2022 at 02:46:48PM -0700, Andrew Morton wrote: > From: Charan Teja Kalla > Subject: mm: madvise: skip unmapped vma holes passed to process_madvise > > The process_madvise() system call is expected to skip holes in vma passed > through 'struct iovec' vector list. But do_madvise, which > process_madvise() calls for each vma, returns ENOMEM in case of unmapped > holes, despite the VMA is processed. > > Thus process_madvise() should treat ENOMEM as expected and consider the > VMA passed to as processed and continue processing other vma's in the > vector list. Returning -ENOMEM to user, despite the VMA is processed, > will be unable to figure out where to start the next madvise. > > Link: https://lkml.kernel.org/r/4f091776142f2ebf7b94018146de72318474e686.1647008754.git.quic_charante@quicinc.com I thought it was still under discussion and Charan will post next version along with previous patch "mm: madvise: return correct bytes advised with process_madvise" https://lore.kernel.org/linux-mm/7207b2f5-6b3e-aea4-aa1b-9c6d849abe34@quicinc.com/ > Fixes: ecb8ac8b1f14("mm/madvise: introduce process_madvise() syscall: an external memory hinting API") > Signed-off-by: Charan Teja Kalla > Cc: David Rientjes > Cc: Michal Hocko > Cc: Minchan Kim > Cc: Nadav Amit > Cc: Stephen Rothwell > Cc: Suren Baghdasaryan > Cc: Vlastimil Babka > Cc: > Signed-off-by: Andrew Morton > --- > > mm/madvise.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > --- a/mm/madvise.c~mm-madvise-skip-unmapped-vma-holes-passed-to-process_madvise > +++ a/mm/madvise.c > @@ -1428,9 +1428,16 @@ SYSCALL_DEFINE5(process_madvise, int, pi > > while (iov_iter_count(&iter)) { > iovec = iov_iter_iovec(&iter); > + /* > + * do_madvise returns ENOMEM if unmapped holes are present > + * in the passed VMA. process_madvise() is expected to skip > + * unmapped holes passed to it in the 'struct iovec' list > + * and not fail because of them. Thus treat -ENOMEM return > + * from do_madvise as valid and continue processing. > + */ > ret = do_madvise(mm, (unsigned long)iovec.iov_base, > iovec.iov_len, behavior); > - if (ret < 0) > + if (ret < 0 && ret != -ENOMEM) > break; > iov_iter_advance(&iter, iovec.iov_len); > } > _