On Wed, 28 Feb 2018 10:54:56 +0100, Michael Tretter wrote: > If a file system is mounted on the nbd during a disconnect, resetting > the size to 0, might change the block size and destroy the buffer_head > mappings. This will cause a infinite loop when the file system looks for > the buffer_heads for flushing. > > Only set the file size to 0, if we are the only opener of the nbd. > > Signed-off-by: Michael Tretter <m.tretter@xxxxxxxxxxxxxx> > --- > drivers/block/nbd.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c > index 5f2a4240a204..0d1dbb60430b 100644 > --- a/drivers/block/nbd.c > +++ b/drivers/block/nbd.c > @@ -1118,7 +1118,8 @@ static int nbd_start_device_ioctl(struct nbd_device *nbd, struct block_device *b > if (ret) > sock_shutdown(nbd); > mutex_lock(&nbd->config_lock); > - bd_set_size(bdev, 0); > + if (bdev->bd_openers <= 1) > + bd_set_size(bdev, 0); > /* user requested, ignore socket errors */ > if (test_bit(NBD_DISCONNECT_REQUESTED, &config->runtime_flags)) > ret = 0; Are there any comments on this patch? Michael
