From nobody Fri Oct 17 10:31:37 2025 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 29781C43217 for ; Wed, 19 Oct 2022 09:16:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233144AbiJSJQS (ORCPT ); Wed, 19 Oct 2022 05:16:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52510 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233035AbiJSJN3 (ORCPT ); Wed, 19 Oct 2022 05:13:29 -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 EA6C590823; Wed, 19 Oct 2022 02:03:31 -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 1A22B61750; Wed, 19 Oct 2022 09:02:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0535DC433D6; Wed, 19 Oct 2022 09:02:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666170164; bh=8jvjNDiaCdUPJjeCJK4JOqJEZvEbt3GWCTDXTZfvlps=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=yoRHaa9d+kM/gv1CffIJvtcCzBVewU/cEfMMkrsT7kl+o+IQiP7ytBwgDoi3F+06b zWRaTnSeTKHI06aCT7ufVAcxkwh7vB/EIqhXd50fENjejOFCJQQ/iCZClZYHwTR0AN 0PEzKzoINSAn0jy+HmCJJ17vYcJP4zvQXD46CmUs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Logan Gunthorpe , Christoph Hellwig , Guoqing Jiang , Song Liu , Sasha Levin Subject: [PATCH 6.0 550/862] md: Remove extra mddev_get() in md_seq_start() Date: Wed, 19 Oct 2022 10:30:37 +0200 Message-Id: <20221019083314.271924843@linuxfoundation.org> X-Mailer: git-send-email 2.38.0 In-Reply-To: <20221019083249.951566199@linuxfoundation.org> References: <20221019083249.951566199@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Logan Gunthorpe [ Upstream commit 3bfc3bcd787c48aa31e4fde4a6dfcef4cd7ee2c2 ] A regression is seen where mddev devices stay permanently after they are stopped due to an elevated reference count. This was tracked down to an extra mddev_get() in md_seq_start(). It only happened rarely because most of the time the md_seq_start() is called with a zero offset. The path with an extra mddev_get() only happens when it starts with a non-zero offset. The commit noted below changed an mddev_get() to check its success but inadvertently left the original call in. Remove the extra call. Fixes: 12a6caf27324 ("md: only delete entries from all_mddevs when the disk= is freed") Signed-off-by: Logan Gunthorpe Reviewed-by: Christoph Hellwig Acked-by: Guoqing Jiang Signed-off-by: Song Liu Signed-off-by: Sasha Levin --- drivers/md/md.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 729be2c5296c..470a975e4be9 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -8156,7 +8156,6 @@ static void *md_seq_start(struct seq_file *seq, loff_= t *pos) list_for_each(tmp,&all_mddevs) if (!l--) { mddev =3D list_entry(tmp, struct mddev, all_mddevs); - mddev_get(mddev); if (!mddev_get(mddev)) continue; spin_unlock(&all_mddevs_lock); --=20 2.35.1