From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp153-168.sina.com.cn (smtp153-168.sina.com.cn [61.135.153.168]) (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 BBB21156CA for ; Wed, 30 Jul 2025 02:08:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=61.135.153.168 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753841345; cv=none; b=MOw9YRVXXj3YcnmYzBDFlBpwvXTrzXfWvhHsW12NTjTg2gEX9oL1GAcS8JjlCHHezwNpkp/ztZkNxcHHNCEAegE6gk/JzVz3NkYRc0PAXy7IQxPcBMUet8rooWWNRgfVXJJyg9ZcazaWlkJLNFmkCpUgiy4wuL6+xf6srlq8Al4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753841345; c=relaxed/simple; bh=o9KBsZRW9asy9Vyz9ECeG7Nlcg5RkCPs98yedGaU8eI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=caVtWPCw5bu7cxmyi3rE2E9N8jVLhUkVy26qARzCMD1LbVk6oZe1HyWpKHGx3fe54X8pp/pe2F6DWdo09mgVWp/4O6ipa4cGbfTIApd3JdO4F0tukdVj1f/afuDsbeFryUA8TEb8tbF4zJAMYVeL2B76ls7nQEaVooEwdYWM3Kg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=sina.com; spf=pass smtp.mailfrom=sina.com; dkim=pass (1024-bit key) header.d=sina.com header.i=@sina.com header.b=EUfiOjrV; arc=none smtp.client-ip=61.135.153.168 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=sina.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sina.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=sina.com header.i=@sina.com header.b="EUfiOjrV" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sina.com; s=201208; t=1753841336; bh=yY9jez1HB94PtjWZDN5sbboUpAgoKw097P/B2TR9a1Q=; h=From:Subject:Date:Message-ID; b=EUfiOjrVViTZsAh9rv9GO6bjaAqlrEP6nSKhVn/yVumRU1H+xXqJmnO5WwkSd5vZ4 9rmQgrPm4bDEfjPh+cEJGFzhykoQ+2xDbxMv+7PtSpGglYZX2lWgFELtbdGxCG0Too Vt1oxGzN67DS4UxMQ5J91L4NatMSnJUrfajp09Es= X-SMAIL-HELO: localhost.localdomain Received: from unknown (HELO localhost.localdomain)([114.249.58.236]) by sina.com (10.54.253.33) with ESMTP id 68897D6E000045B4; Wed, 30 Jul 2025 10:03:28 +0800 (CST) X-Sender: hdanton@sina.com X-Auth-ID: hdanton@sina.com Authentication-Results: sina.com; spf=none smtp.mailfrom=hdanton@sina.com; dkim=none header.i=none; dmarc=none action=none header.from=hdanton@sina.com X-SMAIL-MID: 8040466685343 X-SMAIL-UIID: 9E0DD5E463AD46BD991820629B4AFB70-20250730-100328-1 From: Hillf Danton To: syzbot Cc: linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [fuse?] WARNING: refcount bug in process_scheduled_works Date: Wed, 30 Jul 2025 10:03:17 +0800 Message-ID: <20250730020318.3428-1-hdanton@sina.com> In-Reply-To: <68894408.a00a0220.26d0e1.0012.GAE@google.com> (raw) References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit > Date: Tue, 29 Jul 2025 14:58:32 -0700 [thread overview] > Hello, > > syzbot found the following issue on: > > HEAD commit: ced1b9e0392d Merge tag 'ata-6.17-rc1' of git://git.kernel... > git tree: upstream > console+strace: https://syzkaller.appspot.com/x/log.txt?x=15c89782580000 > kernel config: https://syzkaller.appspot.com/x/.config?x=d51af648924b64c9 > dashboard link: https://syzkaller.appspot.com/bug?extid=9921e319bd6168140b40 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=177f7034580000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=165e44a2580000 #syz test --- x/drivers/md/md.c +++ y/drivers/md/md.c @@ -632,10 +632,13 @@ static void mddev_delayed_delete(struct static void __mddev_put(struct mddev *mddev) { + struct kobject *kobj = &mddev->kobj; + if (mddev->raid_disks || !list_empty(&mddev->disks) || mddev->ctime || mddev->hold_active) return; + BUG_ON(kref_read(&kobj->kref) < 1); /* * Call queue_work inside the spinlock so that flush_workqueue() after * mddev_find will succeed in waiting for the work to be done. @@ -710,6 +713,7 @@ int mddev_init(struct mddev *mddev) INIT_WORK(&mddev->sync_work, md_start_sync); INIT_WORK(&mddev->del_work, mddev_delayed_delete); + kobject_init(&mddev->kobj, &md_ktype); return 0; } @@ -5982,7 +5986,6 @@ struct mddev *md_alloc(dev_t dev, char * if (error) goto out_put_disk; - kobject_init(&mddev->kobj, &md_ktype); error = kobject_add(&mddev->kobj, &disk_to_dev(disk)->kobj, "%s", "md"); if (error) { /* --