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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7E54BC4332F for ; Fri, 1 Apr 2022 18:20:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349161AbiDASWp (ORCPT ); Fri, 1 Apr 2022 14:22:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44756 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346232AbiDASWo (ORCPT ); Fri, 1 Apr 2022 14:22:44 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CF39F38198; Fri, 1 Apr 2022 11:20:54 -0700 (PDT) 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 259EDB82590; Fri, 1 Apr 2022 18:20:53 +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> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 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); } _