The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From b40813ddcd6bf9f01d020804e4cb8febc480b9e4 Mon Sep 17 00:00:00 2001
From: Ming Lei <ming.lei@xxxxxxxxxx>
Date: Wed, 28 Oct 2020 15:24:34 +0800
Subject: [PATCH] nbd: don't update block size after device is started
Mounted NBD device can be resized, one use case is rbd-nbd.
Fix the issue by setting up default block size, then not touch it
in nbd_size_update() any more. This kind of usage is aligned with loop
which has same use case too.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: c8a83a6b54d0 ("nbd: Use set_blocksize() to set device blocksize")
Reported-by: lining <lining2020x@xxxxxxx>
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
Cc: Josef Bacik <josef@xxxxxxxxxxxxxx>
Cc: Jan Kara <jack@xxxxxxx>
Tested-by: lining <lining2020x@xxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 0bed21c0c81b..c4f9ccf5cc2a 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -296,7 +296,7 @@ static void nbd_size_clear(struct nbd_device *nbd)
}
}
-static void nbd_size_update(struct nbd_device *nbd)
+static void nbd_size_update(struct nbd_device *nbd, bool start)
{
struct nbd_config *config = nbd->config;
struct block_device *bdev = bdget_disk(nbd->disk, 0);
@@ -313,7 +313,8 @@ static void nbd_size_update(struct nbd_device *nbd)
if (bdev) {
if (bdev->bd_disk) {
bd_set_nr_sectors(bdev, nr_sectors);
- set_blocksize(bdev, config->blksize);
+ if (start)
+ set_blocksize(bdev, config->blksize);
} else
set_bit(GD_NEED_PART_SCAN, &nbd->disk->state);
bdput(bdev);
@@ -328,7 +329,7 @@ static void nbd_size_set(struct nbd_device *nbd, loff_t blocksize,
config->blksize = blocksize;
config->bytesize = blocksize * nr_blocks;
if (nbd->task_recv != NULL)
- nbd_size_update(nbd);
+ nbd_size_update(nbd, false);
}
static void nbd_complete_rq(struct request *req)
@@ -1308,7 +1309,7 @@ static int nbd_start_device(struct nbd_device *nbd)
args->index = i;
queue_work(nbd->recv_workq, &args->work);
}
- nbd_size_update(nbd);
+ nbd_size_update(nbd, true);
return error;
}
