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Date: Sat, 16 Dec 2023 21:22:41 -0800
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Subject: Re: [syzbot] [block?] INFO: task hung in bdev_release
From: syzbot <syzbot+4da851837827326a7cd4@syzkaller.appspotmail.com>
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Subject: [block?] INFO: task hung in bdev_release
Author: eadavis@qq.com

please test task hung in bdev_release

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git  8c9660f65153

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index b6414e1e645b..3a00ae9b4867 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -475,10 +475,11 @@ static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req)
 		 */
 		struct nbd_sock *nsock = config->socks[cmd->index];
 		cmd->retries++;
-		dev_info(nbd_to_dev(nbd), "Possible stuck request %p: control (%s@%llu,%uB). Runtime %u seconds\n",
+		dev_info(nbd_to_dev(nbd), "Possible stuck request %p: control (%s@%llu,%uB). Runtime %u seconds, nbd: %p, d: %p\n",
 			req, nbdcmd_to_ascii(req_to_nbd_cmd_type(req)),
 			(unsigned long long)blk_rq_pos(req) << 9,
-			blk_rq_bytes(req), (req->timeout / HZ) * cmd->retries);
+			blk_rq_bytes(req), (req->timeout / HZ) * cmd->retries,
+			nbd, nbd->disk);
 
 		mutex_lock(&nsock->tx_lock);
 		if (cmd->cookie != nsock->cookie) {
@@ -733,7 +734,7 @@ static int nbd_read_reply(struct nbd_device *nbd, struct socket *sock,
 	if (result < 0) {
 		if (!nbd_disconnected(nbd->config))
 			dev_err(disk_to_dev(nbd->disk),
-				"Receive control failed (result %d)\n", result);
+				"Receive control failed (result %d), nbd: %p, d: %p\n", result, nbd, nbd->disk);
 		return result;
 	}
 
@@ -1394,6 +1395,9 @@ static int nbd_start_device(struct nbd_device *nbd)
 	}
 	set_bit(NBD_RT_HAS_PID_FILE, &config->runtime_flags);
 
+	if (num_connections == 1 && !nbd->tag_set.timeout)
+		nbd->tag_set.timeout = HZ * 1024;
+
 	nbd_dev_dbg_init(nbd);
 	for (i = 0; i < num_connections; i++) {
 		struct recv_thread_args *args;
@@ -1424,6 +1428,7 @@ static int nbd_start_device(struct nbd_device *nbd)
 		args->nsock = config->socks[i];
 		args->index = i;
 		queue_work(nbd->recv_workq, &args->work);
+		printk("%p, %p, bs: %lld, blks: %lld, c: %d, %s\n", nbd, nbd->disk, config->bytesize, nbd_blksize(config), num_connections, __func__);
 	}
 	return nbd_set_size(nbd, config->bytesize, nbd_blksize(config));
 }