From patchwork Fri Apr 1 18:20:51 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 12798584 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 069F4C433F5 for ; Fri, 1 Apr 2022 18:21:17 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 848848D0002; Fri, 1 Apr 2022 14:21:06 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 7F7BD6B0072; Fri, 1 Apr 2022 14:21:06 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6BF318D0002; Fri, 1 Apr 2022 14:21:06 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.hostedemail.com [64.99.140.26]) by kanga.kvack.org (Postfix) with ESMTP id 5D5BB6B0071 for ; Fri, 1 Apr 2022 14:21:06 -0400 (EDT) Received: from smtpin15.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay13.hostedemail.com (Postfix) with ESMTP id 22EA761A97 for ; Fri, 1 Apr 2022 18:20:56 +0000 (UTC) X-FDA: 79309126512.15.581E540 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by imf21.hostedemail.com (Postfix) with ESMTP id 713351C0023 for ; Fri, 1 Apr 2022 18:20:55 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 1F7D8B82598; Fri, 1 Apr 2022 18:20:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B96F7C340EE; Fri, 1 Apr 2022 18:20:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1648837251; bh=Y1DSYXwwtCvcVdddctf38D7U2PdgnxIbrJmSu/87218=; h=Date:To:From:In-Reply-To:Subject:From; b=osP8n3Ke1SmV2qMXlXYHaPU5rpTMrPzVuGVbGLu7fzthxKy/Nb/d0rrXOCOtTY8ql g0pvBfXeOV1JZBebx3XAqV9SpKVOqBiQRqWHLT8ADy1YiP90f3JsdNoIjFnMrOeXYx rSNvnBfldIXHS6T14uFXLErx4rxchAETMJF0TnsI= Date: Fri, 01 Apr 2022 11:20:51 -0700 To: vbabka@suse.cz,surenb@google.com,stable@vger.kernel.org,rientjes@google.com,nadav.amit@gmail.com,mhocko@suse.com,quic_charante@quicinc.com,akpm@linux-foundation.org,patches@lists.linux.dev,linux-mm@kvack.org,mm-commits@vger.kernel.org,torvalds@linux-foundation.org,akpm@linux-foundation.org From: Andrew Morton In-Reply-To: Subject: [patch 01/16] Revert "mm: madvise: skip unmapped vma holes passed to process_madvise" Message-Id: <20220401182051.B96F7C340EE@smtp.kernel.org> X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 713351C0023 X-Stat-Signature: z5ft3spihj76a51b83b8mew7pxggbq4s X-Rspam-User: Authentication-Results: imf21.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=osP8n3Ke; dmarc=none; spf=pass (imf21.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.68.75 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org X-HE-Tag: 1648837255-462315 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: From: Charan Teja Kalla Subject: Revert "mm: madvise: skip unmapped vma holes passed to process_madvise" This reverts commit 08095d6310a7 ("mm: madvise: skip unmapped vma holes passed to process_madvise") as process_madvise() fails to return the exact processed bytes in other cases too. As an example: if process_madvise() hits mlocked pages after processing some initial bytes passed in [start, end), it just returns EINVAL although some bytes are processed. Thus making an exception only for ENOMEM is partially fixing the problem of returning the proper advised bytes. Thus revert this patch and return proper bytes advised. Link: https://lkml.kernel.org/r/e73da1304a88b6a8a11907045117cccf4c2b8374.1648046642.git.quic_charante@quicinc.com Fixes: 08095d6310a7ce ("mm: madvise: skip unmapped vma holes passed to process_madvise") Signed-off-by: Charan Teja Kalla Acked-by: Michal Hocko Cc: Suren Baghdasaryan Cc: Vlastimil Babka Cc: David Rientjes Cc: Nadav Amit Cc: Signed-off-by: Andrew Morton --- mm/madvise.c | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) --- a/mm/madvise.c~revert-mm-madvise-skip-unmapped-vma-holes-passed-to-process_madvise +++ a/mm/madvise.c @@ -1464,16 +1464,9 @@ 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 && ret != -ENOMEM) + if (ret < 0) break; iov_iter_advance(&iter, iovec.iov_len); }