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 CF999C433EF for ; Fri, 1 Apr 2022 18:28:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349839AbiDASaE (ORCPT ); Fri, 1 Apr 2022 14:30:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59012 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347575AbiDASaD (ORCPT ); Fri, 1 Apr 2022 14:30:03 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3445F1AC72A; Fri, 1 Apr 2022 11:28:14 -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 dfw.source.kernel.org (Postfix) with ESMTPS id C214760F69; Fri, 1 Apr 2022 18:28:13 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 27EE7C2BBE4; Fri, 1 Apr 2022 18:28:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1648837693; bh=Y1DSYXwwtCvcVdddctf38D7U2PdgnxIbrJmSu/87218=; h=Date:To:From:In-Reply-To:Subject:From; b=pMnBwW3Bhg2X9q+7e9HyTQG/VvIQwiOuZM4Bm3z70U3yuluq6p/JLV7GVuJq6bdjy XLOi0V5zSW0dqceXt2TpxHjtNZSY8nzv/YVUobzHmrlzABvJ6G11zIxpbnPucqXiEI XWFVLVVxV+NkiH3qdWLQ3zDIcMUuwstGocPmjgKo= Date: Fri, 01 Apr 2022 11:28:12 -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: <20220401112740.351496714b370467a92207a6@linux-foundation.org> Subject: [patch 01/16] Revert "mm: madvise: skip unmapped vma holes passed to process_madvise" Message-Id: <20220401182813.27EE7C2BBE4@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@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); } _