{"action":"created","issue":{"url":"https://api.github.com/repos/zfsonlinux/zfs/issues/1040","repository_url":"https://api.github.com/repos/zfsonlinux/zfs","labels_url":"https://api.github.com/repos/zfsonlinux/zfs/issues/1040/labels{/name}","comments_url":"https://api.github.com/repos/zfsonlinux/zfs/issues/1040/comments","events_url":"https://api.github.com/repos/zfsonlinux/zfs/issues/1040/events","html_url":"https://github.com/zfsonlinux/zfs/issues/1040","id":7553406,"number":1040,"title":"Processes accessing ZFS/ZPOOL stuck","user":{"login":"basic6","id":2535481,"avatar_url":"https://avatars.githubusercontent.com/u/2535481?v=3","gravatar_id":"","url":"https://api.github.com/users/basic6","html_url":"https://github.com/basic6","followers_url":"https://api.github.com/users/basic6/followers","following_url":"https://api.github.com/users/basic6/following{/other_user}","gists_url":"https://api.github.com/users/basic6/gists{/gist_id}","starred_url":"https://api.github.com/users/basic6/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/basic6/subscriptions","organizations_url":"https://api.github.com/users/basic6/orgs","repos_url":"https://api.github.com/users/basic6/repos","events_url":"https://api.github.com/users/basic6/events{/privacy}","received_events_url":"https://api.github.com/users/basic6/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/zfsonlinux/zfs/labels/Bug%20-%20Minor","name":"Bug - Minor","color":"e11d21"},{"url":"https://api.github.com/repos/zfsonlinux/zfs/labels/Difficulty%20-%20Medium","name":"Difficulty - Medium","color":"207de5"}],"state":"closed","locked":false,"assignee":null,"milestone":{"url":"https://api.github.com/repos/zfsonlinux/zfs/milestones/11","html_url":"https://github.com/zfsonlinux/zfs/milestones/0.7.0","labels_url":"https://api.github.com/repos/zfsonlinux/zfs/milestones/11/labels","id":7013,"number":11,"title":"0.7.0","description":"ZFS on Linux v0.7.0 - Memory management\r\n\r\n","creator":{"login":"behlendorf","id":148917,"avatar_url":"https://avatars.githubusercontent.com/u/148917?v=3","gravatar_id":"","url":"https://api.github.com/users/behlendorf","html_url":"https://github.com/behlendorf","followers_url":"https://api.github.com/users/behlendorf/followers","following_url":"https://api.github.com/users/behlendorf/following{/other_user}","gists_url":"https://api.github.com/users/behlendorf/gists{/gist_id}","starred_url":"https://api.github.com/users/behlendorf/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/behlendorf/subscriptions","organizations_url":"https://api.github.com/users/behlendorf/orgs","repos_url":"https://api.github.com/users/behlendorf/repos","events_url":"https://api.github.com/users/behlendorf/events{/privacy}","received_events_url":"https://api.github.com/users/behlendorf/received_events","type":"User","site_admin":false},"open_issues":144,"closed_issues":160,"state":"open","created_at":"2011-05-03T17:38:46Z","updated_at":"2016-03-25T20:01:37Z","due_on":null,"closed_at":null},"comments":4,"created_at":"2012-10-12T20:33:44Z","updated_at":"2016-03-25T20:01:37Z","closed_at":"2016-03-25T20:01:37Z","body":"I've set up a zpool with 5 drives (RAID-Z2). While this pool was in use, I disconnected one of the drives, to see what happens (if a drive dies). The drive's status (zpool status) changed from \"ONLINE\" to \"UNAVAIL\" (and stayed that way, even when I reconnected the drive).\r\nSome time later (copy processes have been running the whole time writing data to this zpool), ZFS got stuck.\r\nEvery zpool command (e.g., zpool status) would get stuck. Every process trying to access the zpool gets stuck, even a simple ls. None of those stuck processes can be terminated, not even killed (SIGKILL).\r\n\r\nCtrl + Alt + SysRq + W (after echo 1 > /proc/sys/kernel/sysrq) shows a lot of call traces, most of them from udisks-helper. Here are the last 3:\r\nhttp://pastebin.com/W8A4ynkV\r\n\r\nUsing the Ubuntu Natty stable repository package (on Debian):\r\nii  zfsutils                             0.6.0.80-0ubuntu1~natty1          Native ZFS management utilities for Linux\r\n"},"comment":{"url":"https://api.github.com/repos/zfsonlinux/zfs/issues/comments/201463717","html_url":"https://github.com/zfsonlinux/zfs/issues/1040#issuecomment-201463717","issue_url":"https://api.github.com/repos/zfsonlinux/zfs/issues/1040","id":201463717,"user":{"login":"behlendorf","id":148917,"avatar_url":"https://avatars.githubusercontent.com/u/148917?v=3","gravatar_id":"","url":"https://api.github.com/users/behlendorf","html_url":"https://github.com/behlendorf","followers_url":"https://api.github.com/users/behlendorf/followers","following_url":"https://api.github.com/users/behlendorf/following{/other_user}","gists_url":"https://api.github.com/users/behlendorf/gists{/gist_id}","starred_url":"https://api.github.com/users/behlendorf/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/behlendorf/subscriptions","organizations_url":"https://api.github.com/users/behlendorf/orgs","repos_url":"https://api.github.com/users/behlendorf/repos","events_url":"https://api.github.com/users/behlendorf/events{/privacy}","received_events_url":"https://api.github.com/users/behlendorf/received_events","type":"User","site_admin":false},"created_at":"2016-03-25T20:01:37Z","updated_at":"2016-03-25T20:01:37Z","body":"This issue was addressed by commit 417104bdd3c7ce07ec58674dd078f9891c3bc780.  It was possible for commands like `zpool status` to trigger a disk I/O which would never complete when a pool went offline due to the loss of too many devices."}}