From: Anand Jain Date: Mon, 4 May 2020 18:58:26 +0000 (+0800) Subject: btrfs: free alien device after device add X-Git-Tag: v5.4.48~101 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=fd9720b8e95736314999a6d6dfa6c6f60f2634c2;p=platform%2Fkernel%2Flinux-rpi.git btrfs: free alien device after device add commit 7f551d969037cc128eca60688d9c5a300d84e665 upstream. When an old device has new fsid through 'btrfs device add -f ' our fs_devices list has an alien device in one of the fs_devices lists. By having an alien device in fs_devices, we have two issues so far 1. missing device does not not show as missing in the userland 2. degraded mount will fail Both issues are caused by the fact that there's an alien device in the fs_devices list. (Alien means that it does not belong to the filesystem, identified by fsid, or does not contain btrfs filesystem at all, eg. due to overwrite). A device can be scanned/added through the control device ioctls SCAN_DEV, DEVICES_READY or by ADD_DEV. And device coming through the control device is checked against the all other devices in the lists, but this was not the case for ADD_DEV. This patch fixes both issues above by removing the alien device. CC: stable@vger.kernel.org # 5.4+ Signed-off-by: Anand Jain Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 3e64f49..b7885e5 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -2769,8 +2769,18 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path ret = btrfs_commit_transaction(trans); } - /* Update ctime/mtime for libblkid */ + /* + * Now that we have written a new super block to this device, check all + * other fs_devices list if device_path alienates any other scanned + * device. + * We can ignore the return value as it typically returns -EINVAL and + * only succeeds if the device was an alien. + */ + btrfs_forget_devices(device_path); + + /* Update ctime/mtime for blkid or udev */ update_dev_time(device_path); + return ret; error_sysfs: