{"action":"created","issue":{"url":"https://api.github.com/repos/zfsonlinux/zfs/issues/3652","labels_url":"https://api.github.com/repos/zfsonlinux/zfs/issues/3652/labels{/name}","comments_url":"https://api.github.com/repos/zfsonlinux/zfs/issues/3652/comments","events_url":"https://api.github.com/repos/zfsonlinux/zfs/issues/3652/events","html_url":"https://github.com/zfsonlinux/zfs/issues/3652","id":98243457,"number":3652,"title":"CPU stall when disk is removed","user":{"login":"AB17","id":5553456,"avatar_url":"https://avatars.githubusercontent.com/u/5553456?v=3","gravatar_id":"","url":"https://api.github.com/users/AB17","html_url":"https://github.com/AB17","followers_url":"https://api.github.com/users/AB17/followers","following_url":"https://api.github.com/users/AB17/following{/other_user}","gists_url":"https://api.github.com/users/AB17/gists{/gist_id}","starred_url":"https://api.github.com/users/AB17/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/AB17/subscriptions","organizations_url":"https://api.github.com/users/AB17/orgs","repos_url":"https://api.github.com/users/AB17/repos","events_url":"https://api.github.com/users/AB17/events{/privacy}","received_events_url":"https://api.github.com/users/AB17/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/zfsonlinux/zfs/labels/Bug%20-%20Major","name":"Bug - Major","color":"e11d21"}],"state":"open","locked":false,"assignee":null,"milestone":{"url":"https://api.github.com/repos/zfsonlinux/zfs/milestones/32","html_url":"https://github.com/zfsonlinux/zfs/milestones/0.6.5.2","labels_url":"https://api.github.com/repos/zfsonlinux/zfs/milestones/32/labels","id":1320849,"number":32,"title":"0.6.5.2","description":"ZFS on Linux v0.6.5.2 - Point release, includes critical bug fixes and support for new kernels.","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":18,"closed_issues":0,"state":"open","created_at":"2015-09-23T17:58:28Z","updated_at":"2015-09-24T22:11:00Z","due_on":null,"closed_at":null},"comments":17,"created_at":"2015-07-30T19:26:03Z","updated_at":"2015-09-25T01:59:57Z","closed_at":null,"body":"I'm getting a pool lockup when:\r\n\r\n1) Pool is doing IO (read or write)\r\n2) A disk is removed (or fails)\r\n\r\nz_null_int process takes 100% CPU:\r\n\r\n     PID USER      PR  NI    VIRT    RES    SHR S  %CPU %MEM     TIME+ COMMAND                                                                                                                                        \r\n    1424 root       0 -20       0      0      0 R 100.0  0.0   5:00.81 z_null_int                                                                                                                                     \r\n\r\nWe get this at the console just after removal of the disk:\r\n\r\n    blk_update_request: I/O error, dev sdb, sector 2392232\r\n    INFO: rcu_sched self-detected stall on CPU\r\n    INFO: rcu_sched self-detected stall on CPU\r\n    INFO: rcu_sched self-detected stall on CPU\r\n    INFO: rcu_sched self-detected stall on CPU\r\n    INFO: rcu_sched self-detected stall on CPU\r\n\r\nA hard reset of the machine is required.\r\n\r\nI've experienced this on multiple machines with:\r\n1) Local disks connected with LSI HBA\r\n2) SRP disks over InfiniBand\r\n3) Multipath disks\r\n\r\nKernel version is 3.18.19.\r\n\r\nThis only appeared on the **ZFS master** release from **13th July onwards.**\r\nI don't know the specific commit.\r\nThe latest release on 29th July is **still affected** by this issue. I confirmed that today.\r\n\r\nThe latest SPL master is **not affected** and is OK to use.\r\n\r\n\r\n"},"comment":{"url":"https://api.github.com/repos/zfsonlinux/zfs/issues/comments/143101705","html_url":"https://github.com/zfsonlinux/zfs/issues/3652#issuecomment-143101705","issue_url":"https://api.github.com/repos/zfsonlinux/zfs/issues/3652","id":143101705,"user":{"login":"adessemond","id":602713,"avatar_url":"https://avatars.githubusercontent.com/u/602713?v=3","gravatar_id":"","url":"https://api.github.com/users/adessemond","html_url":"https://github.com/adessemond","followers_url":"https://api.github.com/users/adessemond/followers","following_url":"https://api.github.com/users/adessemond/following{/other_user}","gists_url":"https://api.github.com/users/adessemond/gists{/gist_id}","starred_url":"https://api.github.com/users/adessemond/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/adessemond/subscriptions","organizations_url":"https://api.github.com/users/adessemond/orgs","repos_url":"https://api.github.com/users/adessemond/repos","events_url":"https://api.github.com/users/adessemond/events{/privacy}","received_events_url":"https://api.github.com/users/adessemond/received_events","type":"User","site_admin":false},"created_at":"2015-09-25T01:59:57Z","updated_at":"2015-09-25T01:59:57Z","body":"@behlendorf @ kernelOfTruth : echo 0 > /sys/module/spl/parameters/spl_taskq_thread_dynamic did not help in my case (even forced at system startup before importing anything). Will test the patch and report.  "}}