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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 0CDD0C3A5A6 for ; Mon, 26 Aug 2019 23:05:19 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id C526121848 for ; Mon, 26 Aug 2019 23:05:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="sECy1IDo" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C526121848 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 5E2A06B0287; Mon, 26 Aug 2019 19:05:18 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 593C76B0288; Mon, 26 Aug 2019 19:05:18 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4A81D6B0289; Mon, 26 Aug 2019 19:05:18 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0051.hostedemail.com [216.40.44.51]) by kanga.kvack.org (Postfix) with ESMTP id 1FC196B0287 for ; Mon, 26 Aug 2019 19:05:18 -0400 (EDT) Received: from smtpin21.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with SMTP id B22DC181AC9AE for ; Mon, 26 Aug 2019 23:05:17 +0000 (UTC) X-FDA: 75866111874.21.scarf64_68630721f1261 X-HE-Tag: scarf64_68630721f1261 X-Filterd-Recvd-Size: 2577 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf22.hostedemail.com (Postfix) with ESMTP for ; Mon, 26 Aug 2019 23:05:17 +0000 (UTC) Received: from akpm3.svl.corp.google.com (unknown [104.133.8.65]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E2C02206BA; Mon, 26 Aug 2019 23:05:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566860716; bh=cl70OECwhOCqI7sxkc/Ft+EL3YyE5brFJ+VFfmAluBE=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=sECy1IDonKrYQ2nLaj1eiMbxLkbkQ25Ax1DH8KDGu91ViEAU5zM+pMa7lSZY2HIAS oyHC5+L9IuinAqpcegYdcRykO4IfktmcVG510+/9LUwyoYqk791/6hOCdM6ZEHdnE8 E2xpgPr+F7ymNwxz5XjrQqRNz8FzLgvzPhVZcTYM= Date: Mon, 26 Aug 2019 16:05:15 -0700 From: Andrew Morton To: "Gustavo A. R. Silva" Cc: Henry Burns , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/z3fold.c: fix lock/unlock imbalance in z3fold_page_isolate Message-Id: <20190826160515.446dabc587706fc80e5c6e6b@linux-foundation.org> In-Reply-To: <20190826030634.GA4379@embeddedor> References: <20190826030634.GA4379@embeddedor> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.32; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit 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 Sun, 25 Aug 2019 22:06:34 -0500 "Gustavo A. R. Silva" wrote: > Fix lock/unlock imbalance by unlocking *zhdr* before return. > > Addresses-Coverity-ID: 1452811 ("Missing unlock") > Fixes: d776aaa9895e ("mm/z3fold.c: fix race between migration and destruction") > Signed-off-by: Gustavo A. R. Silva > --- > mm/z3fold.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/mm/z3fold.c b/mm/z3fold.c > index e31cd9bd4ed5..75b7962439ff 100644 > --- a/mm/z3fold.c > +++ b/mm/z3fold.c > @@ -1406,6 +1406,7 @@ static bool z3fold_page_isolate(struct page *page, isolate_mode_t mode) > * should freak out. > */ > WARN(1, "Z3fold is experiencing kref problems\n"); > + z3fold_page_unlock(zhdr); > return false; > } > z3fold_page_unlock(zhdr); Looks good, thanks. This is a bit silly: if (..) { ... z3fold_page_unlock(zhdr); return false; } z3fold_page_unlock(zhdr); return false; but presumably the compiler will clean up after us.