From patchwork Fri Mar 1 09:56:54 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu Kuai X-Patchwork-Id: 13578253 X-Patchwork-Delegate: snitzer@redhat.com Received: from dggsgout11.his.huawei.com (dggsgout11.his.huawei.com [45.249.212.51]) (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 AA37B6BFBC for ; Fri, 1 Mar 2024 10:03:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.51 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709287391; cv=none; b=ufU8YV2al7NHVIrIUEbO9yaZxlBz22mqIxyXb7U9OZ9XILZRRGlCYsRGjKGRNu6qxQIgFjEFxspVcgS+sgwSVJ1voEjh5oTfpGYQy995MgIVWRNlEqQDT7V+w7Cntj56aGQllX/iKeHwZhJWoFmgeEowu6n3+Z4i0UGwuKxUTDs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709287391; c=relaxed/simple; bh=tzsmm4I3A6wxqwxdBMCsCEs/m98BNt/dBIkv7eT554g=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Sf1lY4UHFjE5hiNzDfaxU5ptM2ep6mD6W0ykUCilS29uqltMxI1KjVyU0uC+8en1ItpGYD7XwHZ04DYpE1H/soHsvN6Bb885cpSEjWqDN+YPnswaHVrbXwAGRUkAcazHYIzXghkP6tFGPb6OXO3gI9XEddAQTi//WxLJjAYXiPE= 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=45.249.212.51 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 dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4TmNv72thzz4f3lg0 for ; Fri, 1 Mar 2024 18:02:59 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.112]) by mail.maildlp.com (Postfix) with ESMTP id C43831A07FA for ; Fri, 1 Mar 2024 18:03:06 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP1 (Coremail) with SMTP id cCh0CgCXaBHTp+FlqmBuFg--.36874S10; Fri, 01 Mar 2024 18:03:06 +0800 (CST) From: Yu Kuai To: zkabelac@redhat.com, xni@redhat.com, agk@redhat.com, snitzer@kernel.org, mpatocka@redhat.com, dm-devel@lists.linux.dev, song@kernel.org, yukuai3@huawei.com, heinzm@redhat.com, neilb@suse.de, jbrassow@redhat.com Cc: linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com Subject: [PATCH -next 6/9] md/dm-raid: don't call md_reap_sync_thread() directly Date: Fri, 1 Mar 2024 17:56:54 +0800 Message-Id: <20240301095657.662111-7-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240301095657.662111-1-yukuai1@huaweicloud.com> References: <20240301095657.662111-1-yukuai1@huaweicloud.com> Precedence: bulk X-Mailing-List: dm-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: cCh0CgCXaBHTp+FlqmBuFg--.36874S10 X-Coremail-Antispam: 1UD129KBjvJXoW7AF1xAF18KFyDuFy5Ww48JFb_yoW8Kw4fpa yakas8Ar48JrW3ZFZrt3WDWayFv3ZFg34qyFWfG3y3JF1fKF43WF1j9a17ZFWDtayrt34U XFZ8tF45uF4YqFJanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPI14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JF0E3s1l82xGYI kIc2x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2 z4x0Y4vE2Ix0cI8IcVAFwI0_Ar0_tr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F 4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq 3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7 IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4U M4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2 kIc2xKxwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E 14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_WrylIx kGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUCVW8JwCI42IY6xIIjxv20xvEc7CjxVAF wI0_Gr1j6F4UJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Gr 0_Cr1lIxAIcVC2z280aVCY1x0267AKxVW8Jr0_Cr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUQ SdkUUUUU= X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ From: Yu Kuai 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 ac8b37fcf76f..766a0334460e 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 */