nbd: replace kill_bdev() with __invalidate_device() (abbbdf12) · Commits · 戴 / test

When a filesystem is mounted on a nbd device and on a disconnect, because of kill_bdev(), and resetting bdev size to zero, buffer_head mappings are getting destroyed under mounted filesystem. After a bdev size reset(i.e bdev->bd_inode->i_size = 0) on a disconnect, followed by a sys_umount(), generic_shutdown_super()->... ->__sync_blockdev()->... -blkdev_writepages()->... ->do_invalidatepage()->... -discard_buffer() is discarding superblock buffer_head assumed to be in mapped state by ext4_commit_super(). [mlin: ported to 4.11-rc2] Signed-off-by:

Ratna Manoj Bolla <manoj.br@gmail.com> Signed-off-by:

Josef Bacik <jbacik@fb.com> Signed-off-by:

Jens Axboe <axboe@fb.com>

drivers/block/nbd.c

+6 −2

Original line number	Diff line number	Diff line
		@@ -126,6 +126,7 @@ static const char *nbdcmd_to_ascii(int cmd)

		static int nbd_size_clear(struct nbd_device nbd, struct block_device bdev)
		{
		if (bdev->bd_openers <= 1)
		bd_set_size(bdev, 0);
		set_capacity(nbd->disk, 0);
		kobject_uevent(&nbd_to_dev(nbd)->kobj, KOBJ_CHANGE);
		@@ -665,6 +666,8 @@ static void nbd_reset(struct nbd_device *nbd)

		static void nbd_bdev_reset(struct block_device *bdev)
		{
		if (bdev->bd_openers > 1)
		return;
		set_device_ro(bdev, false);
		bdev->bd_inode->i_size = 0;
		if (max_part > 0) {
		@@ -728,7 +731,8 @@ static int nbd_clear_sock(struct nbd_device nbd, struct block_device bdev)
		{
		sock_shutdown(nbd);
		nbd_clear_que(nbd);
		kill_bdev(bdev);

		__invalidate_device(bdev, true);
		nbd_bdev_reset(bdev);
		/*
		* We want to give the run thread a chance to wait for everybody

Admin message