From patchwork Thu Feb 1 09:25:51 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu Kuai X-Patchwork-Id: 13540852 Received: from dggsgout12.his.huawei.com (unknown [45.249.212.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6941215B990; Thu, 1 Feb 2024 09:30:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.56 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706779834; cv=none; b=lEpLZ8jXEOpHJRBuHp1DSQhgRlqHuJzSZaOR2PoWIH/mam7h59ihptqksKR1AqNetjK7OK154hPbJgvV79AUl3IENvM7ZcG2KKOoGhaUezHJMfwJuIqVB6E+wUYkI8MWtMUOX2548aPAckbNjNs3SmXerz312in52YN2VDxHdgM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706779834; c=relaxed/simple; bh=P78HzqbyoW17tfVjgGA+69KAblnYGxtOVqNCc1oclCo=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=tykn6fFwNjbVGh4uPTvZF1t7l3WNDCwTek1JD/+QsQj7BI0oOWPh32j9wKZGUlTadiOcFExJ8kl8T86bMv2z248PGLFeAcIyzp0FMs+Y+KDEhRjJNZ+13ACVDQCMRfM8pDVl8EV5mAPUGuoIYPHWjFpwwiCY/dP3wmglruoQn68= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.163.235]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4TQYXx1zxMz4f3l7R; Thu, 1 Feb 2024 17:30:25 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.112]) by mail.maildlp.com (Postfix) with ESMTP id 7855C1A027B; Thu, 1 Feb 2024 17:30:29 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP1 (Coremail) with SMTP id cCh0CgCXaBGtZLtl8V6KCg--.33515S10; Thu, 01 Feb 2024 17:30:29 +0800 (CST) From: Yu Kuai To: mpatocka@redhat.com, heinzm@redhat.com, xni@redhat.com, blazej.kucman@linux.intel.com, agk@redhat.com, snitzer@kernel.org, dm-devel@lists.linux.dev, song@kernel.org, yukuai3@huawei.com, jbrassow@f14.redhat.com, neilb@suse.de, shli@fb.com, akpm@osdl.org Cc: linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com Subject: [PATCH v5 06/14] md: fix missing release of 'active_io' for flush Date: Thu, 1 Feb 2024 17:25:51 +0800 Message-Id: <20240201092559.910982-7-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240201092559.910982-1-yukuai1@huaweicloud.com> References: <20240201092559.910982-1-yukuai1@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-raid@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: cCh0CgCXaBGtZLtl8V6KCg--.33515S10 X-Coremail-Antispam: 1UD129KBjvJXoW7Ww1UCw1Utw1xZF4kXr1fZwb_yoW8WF4fp3 y8tas8tr4UGF98t398JF48WF95W3WUtay09FZxAw13AFnxWFs8K39agrW8Xr95Gr1fJ398 ur4jgr1DWa4UWFUanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUP214x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JF0E3s1l82xGYI kIc2x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2 z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Cr1j6r xdM28EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0D M2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjx v20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr0_Gr1l F7xvr2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7M4IIrI8v6xkF7I0E8cxan2 IY04v7MxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrVAF wI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVW8ZVWrXwCIc4 0Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1I6r4UMIIF0xvE2Ix0cI8IcVCY1x0267AK xVW8Jr0_Cr1UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJV W8JwCI42IY6I8E87Iv6xkF7I0E14v26r4UJVWxJrUvcSsGvfC2KfnxnUUI43ZEXa7VUbmZ X7UUUUU== X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ From: Yu Kuai submit_flushes atomic_set(&mddev->flush_pending, 1); rdev_for_each_rcu(rdev, mddev) atomic_inc(&mddev->flush_pending); bi->bi_end_io = md_end_flush submit_bio(bi); /* flush io is done first */ md_end_flush if (atomic_dec_and_test(&mddev->flush_pending)) percpu_ref_put(&mddev->active_io) -> active_io is not released if (atomic_dec_and_test(&mddev->flush_pending)) -> missing release of active_io For consequence, mddev_suspend() will wait for 'active_io' to be zero forever. Fix this problem by releasing 'active_io' in submit_flushes() if 'flush_pending' is decreased to zero. Fixes: fa2bbff7b0b4 ("md: synchronize flush io with array reconfiguration") Reported-by: Blazej Kucman Closes: https://lore.kernel.org/lkml/20240130172524.0000417b@linux.intel.com/ Signed-off-by: Yu Kuai --- drivers/md/md.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 85fde05c37dd..9e41a9aaba8b 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -579,8 +579,12 @@ static void submit_flushes(struct work_struct *ws) rcu_read_lock(); } rcu_read_unlock(); - if (atomic_dec_and_test(&mddev->flush_pending)) + if (atomic_dec_and_test(&mddev->flush_pending)) { + /* The pair is percpu_ref_get() from md_flush_request() */ + percpu_ref_put(&mddev->active_io); + queue_work(md_wq, &mddev->flush_work); + } } static void md_submit_flush_data(struct work_struct *ws)