4.9-stable review patch. If anyone has any objections, please let me know.
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From: Jun Piao piaojun@huawei.com
[ Upstream commit bb34f24c7d2c98d0c81838a7700e6068325b17a0 ]
We should not handle migrate lockres if we are already in 'DLM_CTXT_IN_SHUTDOWN', as that will cause lockres remains after leaving dlm domain. At last other nodes will get stuck into infinite loop when requsting lock from us.
The problem is caused by concurrency umount between nodes. Before receiveing N1's DLM_BEGIN_EXIT_DOMAIN_MSG, N2 has picked up N1 as the migrate target. So N2 will continue sending lockres to N1 even though N1 has left domain.
N1 N2 (owner) touch file
access the file, and get pr lock
begin leave domain and pick up N1 as new owner
begin leave domain and migrate all lockres done
begin migrate lockres to N1
end leave domain, but the lockres left unexpectedly, because migrate task has passed
[piaojun@huawei.com: v3] Link: http://lkml.kernel.org/r/5A9CBD19.5020107@huawei.com Link: http://lkml.kernel.org/r/5A99F028.2090902@huawei.com Signed-off-by: Jun Piao piaojun@huawei.com Reviewed-by: Yiwen Jiang jiangyiwen@huawei.com Reviewed-by: Joseph Qi jiangqi903@gmail.com Reviewed-by: Changwei Ge ge.changwei@h3c.com Cc: Mark Fasheh mark@fasheh.com Cc: Joel Becker jlbec@evilplan.org Cc: Junxiao Bi junxiao.bi@oracle.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/ocfs2/dlm/dlmdomain.c | 14 -------------- fs/ocfs2/dlm/dlmdomain.h | 25 ++++++++++++++++++++++++- fs/ocfs2/dlm/dlmrecovery.c | 9 +++++++++ 3 files changed, 33 insertions(+), 15 deletions(-)
--- a/fs/ocfs2/dlm/dlmdomain.c +++ b/fs/ocfs2/dlm/dlmdomain.c @@ -675,20 +675,6 @@ static void dlm_leave_domain(struct dlm_ spin_unlock(&dlm->spinlock); }
-int dlm_shutting_down(struct dlm_ctxt *dlm) -{ - int ret = 0; - - spin_lock(&dlm_domain_lock); - - if (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN) - ret = 1; - - spin_unlock(&dlm_domain_lock); - - return ret; -} - void dlm_unregister_domain(struct dlm_ctxt *dlm) { int leave = 0; --- a/fs/ocfs2/dlm/dlmdomain.h +++ b/fs/ocfs2/dlm/dlmdomain.h @@ -28,7 +28,30 @@ extern spinlock_t dlm_domain_lock; extern struct list_head dlm_domains;
-int dlm_shutting_down(struct dlm_ctxt *dlm); +static inline int dlm_joined(struct dlm_ctxt *dlm) +{ + int ret = 0; + + spin_lock(&dlm_domain_lock); + if (dlm->dlm_state == DLM_CTXT_JOINED) + ret = 1; + spin_unlock(&dlm_domain_lock); + + return ret; +} + +static inline int dlm_shutting_down(struct dlm_ctxt *dlm) +{ + int ret = 0; + + spin_lock(&dlm_domain_lock); + if (dlm->dlm_state == DLM_CTXT_IN_SHUTDOWN) + ret = 1; + spin_unlock(&dlm_domain_lock); + + return ret; +} + void dlm_fire_domain_eviction_callbacks(struct dlm_ctxt *dlm, int node_num);
--- a/fs/ocfs2/dlm/dlmrecovery.c +++ b/fs/ocfs2/dlm/dlmrecovery.c @@ -1378,6 +1378,15 @@ int dlm_mig_lockres_handler(struct o2net if (!dlm_grab(dlm)) return -EINVAL;
+ if (!dlm_joined(dlm)) { + mlog(ML_ERROR, "Domain %s not joined! " + "lockres %.*s, master %u\n", + dlm->name, mres->lockname_len, + mres->lockname, mres->master); + dlm_put(dlm); + return -EINVAL; + } + BUG_ON(!(mres->flags & (DLM_MRES_RECOVERY|DLM_MRES_MIGRATION)));
real_master = mres->master;