From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 0CE0E53370; Mon, 1 Apr 2024 15:54:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711986861; cv=none; b=SlJPgbldspNnkORQrBT6ZoqnSqMMV7a7Hyk9OHKpoOJwjDYQE0+dhTARAk6CaV1y6TrFwTr5Pzi+8yVFcsBF2c/lEKbXbKQplCO0xh7VPYyJVQ9HdMbMdbzuyNWkCRFu73YsOCsPbx13Hh5ylbqCuNEUG59CowL8M245oqXxnto= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711986861; c=relaxed/simple; bh=vNCxTrfr7elRRcBO9nGgQClAWt8GidNvWuTWRfG1690=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Q4o268nPdQUfbD4zKqzAYj5qKM4Ggc46a0J5DYqOhwNDRkITM0Qd4lyfLMYsWkqotBNmUqTg6GUeRh64QXjmB9ljNzue5ZNTXJ7XEEmMKTGSAe16j9pw+Vj1mHH6xUbPAPQnkHSA6cO/qU4yPqtKS1h2WU6fR2hUc5busZ1kd0I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Wi1mvles; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Wi1mvles" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 31A40C433F1; Mon, 1 Apr 2024 15:54:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1711986860; bh=vNCxTrfr7elRRcBO9nGgQClAWt8GidNvWuTWRfG1690=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Wi1mvleslNQ7tgBwEVhwHJiZEzIckZ4+N207M66egBZ411X2iioNIWDto2uUhohKQ ksex3RHyJOdlx4cgGkC1amxs42yDYriIbABeIqc9hFE+5X8VT6Gjo7NgQMsuZnv7HV 9/VnPXiVtSunYZnWfsiz4tvkztI8bBadnc7BEMw4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yu Kuai , Xiao Ni , Mike Snitzer , Song Liu , Sasha Levin Subject: [PATCH 6.8 109/399] md/dm-raid: dont call md_reap_sync_thread() directly Date: Mon, 1 Apr 2024 17:41:15 +0200 Message-ID: <20240401152552.442293018@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240401152549.131030308@linuxfoundation.org> References: <20240401152549.131030308@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yu Kuai [ Upstream commit cd32b27a66db8776d8b8e82ec7d7dde97a8693b0 ] 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") Cc: stable@vger.kernel.org # v6.7+ Signed-off-by: Yu Kuai Signed-off-by: Xiao Ni Acked-by: Mike Snitzer Signed-off-by: Song Liu Link: https://lore.kernel.org/r/20240305072306.2562024-7-yukuai1@huaweicloud.com Signed-off-by: Sasha Levin --- 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 fff9336fee767..8d38cdb221453 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 */ -- 2.43.0