From patchwork Wed Jan 24 09:14:17 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu Kuai X-Patchwork-Id: 13528842 Received: from szxga04-in.huawei.com (szxga04-in.huawei.com [45.249.212.190]) (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 B21DD1946B; Wed, 24 Jan 2024 09:20:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.190 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706088021; cv=none; b=p58wKP0zntS+Hq/qP1feSwWm5lkzhvO4sM4gh9BKe0maP14wyuq4oKSuYK4B7xreKyqPoM1UlrOhdleO6bXwyrrH5RJ+I1dHuSmnLfga2WZ0E/y+/O7kHXeO7zc0IyUKilysK5kykPo+SRY2+PndvxCFMiESip9lOoZF5c5Pf8o= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706088021; c=relaxed/simple; bh=kJ1nYmW4cicbBwQfSgo5X6zUUeLx3T+g5jG9se6tsaM=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=m75eKYQdjrhjGTt9Yn6xguJyfeI1jhahqwRM0PYL7AtDuc6b3O91jrT8MNhL2YVhBMvMxJd63kBJNAzcyB5F0mkMK2J9phIeJkQUbMlg5jUru9u94ogVFChVWflgTA+/yBKBE3OkfdEaPVOoOPzx/3x4ZW/mXpq+MfymYOe4844= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.190 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.88.214]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4TKdfx2jxGz29kj6; Wed, 24 Jan 2024 17:18:33 +0800 (CST) Received: from kwepemm600009.china.huawei.com (unknown [7.193.23.164]) by mail.maildlp.com (Postfix) with ESMTPS id 987251A0172; Wed, 24 Jan 2024 17:20:02 +0800 (CST) Received: from huawei.com (10.175.104.67) by kwepemm600009.china.huawei.com (7.193.23.164) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.35; Wed, 24 Jan 2024 17:18:24 +0800 From: Yu Kuai To: , , , , , , , , , , , CC: , , , , Subject: [PATCH v2 07/11] md/dm-raid: don't call md_reap_sync_thread() directly Date: Wed, 24 Jan 2024 17:14:17 +0800 Message-ID: <20240124091421.1261579-8-yukuai3@huawei.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240124091421.1261579-1-yukuai3@huawei.com> References: <20240124091421.1261579-1-yukuai3@huawei.com> Precedence: bulk X-Mailing-List: linux-raid@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To kwepemm600009.china.huawei.com (7.193.23.164) Currently md_reap_sync_thread() is called from raid_message() directly without holding 'reconfig_mutex', this is definitely unsafe because md_reap_sync_thread() can change many fields that is protected by 'reconfig_mutex'. However, hold 'reconfig_mutex' here is still problematic because this will cause deadlock, for example, commit 130443d60b1b ("md: refactor idle/frozen_sync_thread() to fix deadlock"). Fix this problem by using stop_sync_thread() to unregister sync_thread, like md/raid did. Fixes: be83651f0050 ("DM RAID: Add message/status support for changing sync action") Signed-off-by: Yu Kuai --- drivers/md/dm-raid.c | 28 ++++++++++++++++++---------- 1 file changed, 18 insertions(+), 10 deletions(-) diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c index 5ce3c6020b1b..6b6c011d9f69 100644 --- a/drivers/md/dm-raid.c +++ b/drivers/md/dm-raid.c @@ -3719,6 +3719,7 @@ static int raid_message(struct dm_target *ti, unsigned int argc, char **argv, { struct raid_set *rs = ti->private; struct mddev *mddev = &rs->md; + int ret = 0; if (!mddev->pers || !mddev->pers->sync_request) return -EINVAL; @@ -3726,17 +3727,24 @@ static int raid_message(struct dm_target *ti, unsigned int argc, char **argv, if (test_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) return -EBUSY; - if (!strcasecmp(argv[0], "frozen")) - set_bit(MD_RECOVERY_FROZEN, &mddev->recovery); - else - clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery); + if (!strcasecmp(argv[0], "frozen")) { + ret = mddev_lock(mddev); + if (ret) + return ret; - if (!strcasecmp(argv[0], "idle") || !strcasecmp(argv[0], "frozen")) { - if (mddev->sync_thread) { - set_bit(MD_RECOVERY_INTR, &mddev->recovery); - md_reap_sync_thread(mddev); - } - } else if (decipher_sync_action(mddev, mddev->recovery) != st_idle) + md_frozen_sync_thread(mddev); + mddev_unlock(mddev); + } else if (!strcasecmp(argv[0], "idle")) { + ret = mddev_lock(mddev); + if (ret) + return ret; + + md_idle_sync_thread(mddev); + mddev_unlock(mddev); + } + + clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery); + if (decipher_sync_action(mddev, mddev->recovery) != st_idle) return -EBUSY; else if (!strcasecmp(argv[0], "resync")) ; /* MD_RECOVERY_NEEDED set below */