linux_dsm_epyc7002/fs/ocfs2
Junxiao Bi ded2cf7141 ocfs2: dlm: fix recovery hung
There is a race window in dlm_do_recovery() between dlm_remaster_locks()
and dlm_reset_recovery() when the recovery master nearly finish the
recovery process for a dead node.  After the master sends FINALIZE_RECO
message in dlm_remaster_locks(), another node may become the recovery
master for another dead node, and then send the BEGIN_RECO message to
all the nodes included the old master, in the handler of this message
dlm_begin_reco_handler() of old master, dlm->reco.dead_node and
dlm->reco.new_master will be set to the second dead node and the new
master, then in dlm_reset_recovery(), these two variables will be reset
to default value.  This will cause new recovery master can not finish
the recovery process and hung, at last the whole cluster will hung for
recovery.

old recovery master:                                 new recovery master:
dlm_remaster_locks()
                                                  become recovery master for
                                                  another dead node.
                                                  dlm_send_begin_reco_message()
dlm_begin_reco_handler()
{
 if (dlm->reco.state & DLM_RECO_STATE_FINALIZE) {
  return -EAGAIN;
 }
 dlm_set_reco_master(dlm, br->node_idx);
 dlm_set_reco_dead_node(dlm, br->dead_node);
}
dlm_reset_recovery()
{
 dlm_set_reco_dead_node(dlm, O2NM_INVALID_NODE_NUM);
 dlm_set_reco_master(dlm, O2NM_INVALID_NODE_NUM);
}
                                                  will hang in dlm_remaster_locks() for
                                                  request dlm locks info

Before send FINALIZE_RECO message, recovery master should set
DLM_RECO_STATE_FINALIZE for itself and clear it after the recovery done,
this can break the race windows as the BEGIN_RECO messages will not be
handled before DLM_RECO_STATE_FINALIZE flag is cleared.

A similar race may happen between new recovery master and normal node
which is in dlm_finalize_reco_handler(), also fix it.

Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Srinivas Eeda <srinivas.eeda@oracle.com>
Reviewed-by: Wengang Wang <wen.gang.wang@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03 16:20:54 -07:00
..
cluster Merge branch 'for-3.14/core' of git://git.kernel.dk/linux-block 2014-01-30 11:19:05 -08:00
dlm ocfs2: dlm: fix recovery hung 2014-04-03 16:20:54 -07:00
dlmfs
acl.c ocfs2: use generic posix ACL infrastructure 2014-01-25 23:58:21 -05:00
acl.h ocfs2: use generic posix ACL infrastructure 2014-01-25 23:58:21 -05:00
alloc.c ocfs2: improve fsync efficiency and fix deadlock between aio_write and sync_file 2014-04-03 16:20:53 -07:00
alloc.h
aops.c ocfs2: improve fsync efficiency and fix deadlock between aio_write and sync_file 2014-04-03 16:20:53 -07:00
aops.h ocfs2: change ip_unaligned_aio to of type mutex from atomit_t 2014-04-03 16:20:53 -07:00
blockcheck.c
blockcheck.h
buffer_head_io.c
buffer_head_io.h
dcache.c
dcache.h
dir.c ocfs2: improve fsync efficiency and fix deadlock between aio_write and sync_file 2014-04-03 16:20:53 -07:00
dir.h
dlmglue.c
dlmglue.h
export.c
export.h
extent_map.c
extent_map.h
file.c ocfs2: improve fsync efficiency and fix deadlock between aio_write and sync_file 2014-04-03 16:20:53 -07:00
file.h
heartbeat.c
heartbeat.h
inode.c ocfs2: improve fsync efficiency and fix deadlock between aio_write and sync_file 2014-04-03 16:20:53 -07:00
inode.h ocfs2: improve fsync efficiency and fix deadlock between aio_write and sync_file 2014-04-03 16:20:53 -07:00
ioctl.c ocfs2: adjust minlen with discard_granularity in the FITRIM ioctl 2014-01-21 16:19:42 -08:00
ioctl.h
journal.c
journal.h ocfs2: improve fsync efficiency and fix deadlock between aio_write and sync_file 2014-04-03 16:20:53 -07:00
Kconfig
localalloc.c ocfs2: free allocated clusters if error occurs after ocfs2_claim_clusters 2014-02-06 13:48:51 -08:00
localalloc.h ocfs2: free allocated clusters if error occurs after ocfs2_claim_clusters 2014-02-06 13:48:51 -08:00
locks.c
locks.h
Makefile
mmap.c
mmap.h
move_extents.c
move_extents.h
namei.c ocfs2: improve fsync efficiency and fix deadlock between aio_write and sync_file 2014-04-03 16:20:53 -07:00
namei.h
ocfs1_fs_compat.h
ocfs2_fs.h
ocfs2_ioctl.h
ocfs2_lockid.h
ocfs2_lockingver.h
ocfs2_trace.h
ocfs2.h
quota_global.c ocfs2: fix quota file corruption 2014-03-04 07:55:48 -08:00
quota_local.c ocfs2: fix quota file corruption 2014-03-04 07:55:48 -08:00
quota.h
refcounttree.c ocfs2: use generic posix ACL infrastructure 2014-01-25 23:58:21 -05:00
refcounttree.h
reservations.c
reservations.h
resize.c
resize.h
slot_map.c
slot_map.h
stack_o2cb.c
stack_user.c ocfs2: fix sparse non static symbol warning 2014-01-21 16:19:42 -08:00
stackglue.c ocfs2: check if cluster name exists before deref 2014-03-28 13:56:58 -07:00
stackglue.h
suballoc.c
suballoc.h
super.c ocfs2: improve fsync efficiency and fix deadlock between aio_write and sync_file 2014-04-03 16:20:53 -07:00
super.h
symlink.c
symlink.h
sysfile.c
sysfile.h
uptodate.c
uptodate.h
xattr.c ocfs2: use generic posix ACL infrastructure 2014-01-25 23:58:21 -05:00
xattr.h ocfs2: use generic posix ACL infrastructure 2014-01-25 23:58:21 -05:00