From 2eebd94379c56adc97a1cbac58ef3b9ec0573123 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Thu, 21 Feb 2019 14:51:25 -0500 Subject: [PATCH 1433/2944] NFS: Fix a soft lockup in the delegation recovery code task #28557789 [ Upstream commit 6f9449be53f3ce383caed797708b332ede8d952c ] Fix a soft lockup when NFS client delegation recovery is attempted but the inode is in the process of being freed. When the igrab(inode) call fails, and we have to restart the recovery process, we need to ensure that we won't attempt to recover the same delegation again. Fixes: 45870d6909d5a ("NFSv4.1: Test delegation stateids when server...") Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin Signed-off-by: Jeffle Xu Acked-by: Joseph Qi --- fs/nfs/delegation.c | 20 ++++++++++++-------- fs/nfs/delegation.h | 1 + 2 files changed, 13 insertions(+), 8 deletions(-) diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c index 74ff459..b0c0c2f 100644 --- a/fs/nfs/delegation.c +++ b/fs/nfs/delegation.c @@ -240,6 +240,8 @@ static struct inode *nfs_delegation_grab_inode(struct nfs_delegation *delegation spin_lock(&delegation->lock); if (delegation->inode != NULL) inode = igrab(delegation->inode); + if (!inode) + set_bit(NFS_DELEGATION_INODE_FREEING, &delegation->flags); spin_unlock(&delegation->lock); return inode; } @@ -955,10 +957,11 @@ void nfs_delegation_reap_unclaimed(struct nfs_client *clp) list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) { list_for_each_entry_rcu(delegation, &server->delegations, super_list) { - if (test_bit(NFS_DELEGATION_RETURNING, - &delegation->flags)) - continue; - if (test_bit(NFS_DELEGATION_NEED_RECLAIM, + if (test_bit(NFS_DELEGATION_INODE_FREEING, + &delegation->flags) || + test_bit(NFS_DELEGATION_RETURNING, + &delegation->flags) || + test_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags) == 0) continue; if (!nfs_sb_active(server->super)) @@ -1064,10 +1067,11 @@ void nfs_reap_expired_delegations(struct nfs_client *clp) list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) { list_for_each_entry_rcu(delegation, &server->delegations, super_list) { - if (test_bit(NFS_DELEGATION_RETURNING, - &delegation->flags)) - continue; - if (test_bit(NFS_DELEGATION_TEST_EXPIRED, + if (test_bit(NFS_DELEGATION_INODE_FREEING, + &delegation->flags) || + test_bit(NFS_DELEGATION_RETURNING, + &delegation->flags) || + test_bit(NFS_DELEGATION_TEST_EXPIRED, &delegation->flags) == 0) continue; if (!nfs_sb_active(server->super)) diff --git a/fs/nfs/delegation.h b/fs/nfs/delegation.h index dd0f3ee..f09b153 100644 --- a/fs/nfs/delegation.h +++ b/fs/nfs/delegation.h @@ -34,6 +34,7 @@ enum { NFS_DELEGATION_RETURNING, NFS_DELEGATION_REVOKED, NFS_DELEGATION_TEST_EXPIRED, + NFS_DELEGATION_INODE_FREEING, }; int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, -- 1.8.3.1