From aa9ddcd4b5557102fa25695c11904f249b4dec49 Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Thu, 2 Aug 2012 10:22:20 -0400 Subject: [PATCH] Btrfs: do not use missing devices when showing devname If you do the following mkfs.btrfs /dev/sdb /dev/sdc rmmod btrfs dd if=/dev/zero of=/dev/sdb bs=1M count=1 mount -o degraded /dev/sdc /mnt/btrfs-test the box will panic trying to deref the name for the missing dev since it is the lower numbered devid. So fix show_devname to not use missing devices. Thanks, Signed-off-by: Josef Bacik --- fs/btrfs/super.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 75ee2c7791f0..2e06f124f284 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1505,6 +1505,8 @@ static int btrfs_show_devname(struct seq_file *m, struct dentry *root) while (cur_devices) { head = &cur_devices->devices; list_for_each_entry(dev, head, dev_list) { + if (dev->missing) + continue; if (!first_dev || dev->devid < first_dev->devid) first_dev = dev; } -- 2.34.1