[v2] NFSv4.1: handle memory allocation failure in nfs4_schedule_state_manager()
Commit Message
If memory allocation fail in nfs4_schedule_state_manager() when mount
NFSv4.1/NFSv4.2, nfs4_run_state_manager() will not be called, and current
construction state will never be marked as ready or failed,
nfs_wait_client_init_complete() will wait forever, as shown below:
syscall(mount)
...
nfs4_init_client
nfs4_discover_server_trunking
nfs41_discover_server_trunking
nfs4_schedule_state_manager
kthread_run /* nfs4_run_state_manager() will not be called */
kthread_create
kthread_create_on_node
__kthread_create_on_node
create = kmalloc() = NULL
return ERR_PTR(-ENOMEM)
nfs_wait_client_init_complete /* wait forever */
Fix this by checking return value of nfs4_schedule_state_manager() which
can indicate whether kernel thread is created successful.
Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com>
---
fs/nfs/nfs4_fs.h | 2 +-
fs/nfs/nfs4state.c | 17 +++++++++++------
2 files changed, 12 insertions(+), 7 deletions(-)
Comments
Hi Trond:
Do you have any suggestions for this patch ?
在 2022/11/12 15:30, ChenXiaoSong 写道:
> If memory allocation fail in nfs4_schedule_state_manager() when mount
> NFSv4.1/NFSv4.2, nfs4_run_state_manager() will not be called, and current
> construction state will never be marked as ready or failed,
> nfs_wait_client_init_complete() will wait forever, as shown below:
>
> syscall(mount)
> ...
> nfs4_init_client
> nfs4_discover_server_trunking
> nfs41_discover_server_trunking
> nfs4_schedule_state_manager
> kthread_run /* nfs4_run_state_manager() will not be called */
> kthread_create
> kthread_create_on_node
> __kthread_create_on_node
> create = kmalloc() = NULL
> return ERR_PTR(-ENOMEM)
> nfs_wait_client_init_complete /* wait forever */
>
> Fix this by checking return value of nfs4_schedule_state_manager() which
> can indicate whether kernel thread is created successful.
>
> Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com>
> ---
> fs/nfs/nfs4_fs.h | 2 +-
> fs/nfs/nfs4state.c | 17 +++++++++++------
> 2 files changed, 12 insertions(+), 7 deletions(-)
>
> diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
> index cfef738d765e..74c6d1504010 100644
> --- a/fs/nfs/nfs4_fs.h
> +++ b/fs/nfs/nfs4_fs.h
> @@ -502,7 +502,7 @@ extern int nfs4_state_mark_reclaim_nograce(struct nfs_client *, struct nfs4_stat
> extern void nfs4_schedule_lease_recovery(struct nfs_client *);
> extern int nfs4_wait_clnt_recover(struct nfs_client *clp);
> extern int nfs4_client_recover_expired_lease(struct nfs_client *clp);
> -extern void nfs4_schedule_state_manager(struct nfs_client *);
> +extern int nfs4_schedule_state_manager(struct nfs_client *);
> extern void nfs4_schedule_path_down_recovery(struct nfs_client *clp);
> extern int nfs4_schedule_stateid_recovery(const struct nfs_server *, struct nfs4_state *);
> extern int nfs4_schedule_migration_recovery(const struct nfs_server *);
> diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
> index a2d2d5d1b088..e32739fb9151 100644
> --- a/fs/nfs/nfs4state.c
> +++ b/fs/nfs/nfs4state.c
> @@ -376,8 +376,9 @@ int nfs41_discover_server_trunking(struct nfs_client *clp,
> else
> set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
> }
> - nfs4_schedule_state_manager(clp);
> - status = nfs_wait_client_init_complete(clp);
> + status = nfs4_schedule_state_manager(clp);
> + if (!status)
> + status = nfs_wait_client_init_complete(clp);
> if (status < 0)
> nfs_put_client(clp);
> return status;
> @@ -1201,11 +1202,12 @@ static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
> /*
> * Schedule the nfs_client asynchronous state management routine
> */
> -void nfs4_schedule_state_manager(struct nfs_client *clp)
> +int nfs4_schedule_state_manager(struct nfs_client *clp)
> {
> struct task_struct *task;
> char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1];
> struct rpc_clnt *cl = clp->cl_rpcclient;
> + int ret = 0;
>
> while (cl != cl->cl_parent)
> cl = cl->cl_parent;
> @@ -1213,7 +1215,8 @@ void nfs4_schedule_state_manager(struct nfs_client *clp)
> set_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state);
> if (test_and_set_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state) != 0) {
> wake_up_var(&clp->cl_state);
> - return;
> + ret = -EIO;
> + goto out;
> }
> set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
> __module_get(THIS_MODULE);
> @@ -1228,13 +1231,15 @@ void nfs4_schedule_state_manager(struct nfs_client *clp)
> rcu_read_unlock();
> task = kthread_run(nfs4_run_state_manager, clp, "%s", buf);
> if (IS_ERR(task)) {
> - printk(KERN_ERR "%s: kthread_run: %ld\n",
> - __func__, PTR_ERR(task));
> + ret = PTR_ERR(task);
> + printk(KERN_ERR "%s: kthread_run: %d\n", __func__, ret);
> nfs4_clear_state_manager_bit(clp);
> clear_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state);
> nfs_put_client(clp);
> module_put(THIS_MODULE);
> }
> +out:
> + return ret;
> }
>
> /*
>
@@ -502,7 +502,7 @@ extern int nfs4_state_mark_reclaim_nograce(struct nfs_client *, struct nfs4_stat
extern void nfs4_schedule_lease_recovery(struct nfs_client *);
extern int nfs4_wait_clnt_recover(struct nfs_client *clp);
extern int nfs4_client_recover_expired_lease(struct nfs_client *clp);
-extern void nfs4_schedule_state_manager(struct nfs_client *);
+extern int nfs4_schedule_state_manager(struct nfs_client *);
extern void nfs4_schedule_path_down_recovery(struct nfs_client *clp);
extern int nfs4_schedule_stateid_recovery(const struct nfs_server *, struct nfs4_state *);
extern int nfs4_schedule_migration_recovery(const struct nfs_server *);
@@ -376,8 +376,9 @@ int nfs41_discover_server_trunking(struct nfs_client *clp,
else
set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
}
- nfs4_schedule_state_manager(clp);
- status = nfs_wait_client_init_complete(clp);
+ status = nfs4_schedule_state_manager(clp);
+ if (!status)
+ status = nfs_wait_client_init_complete(clp);
if (status < 0)
nfs_put_client(clp);
return status;
@@ -1201,11 +1202,12 @@ static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
/*
* Schedule the nfs_client asynchronous state management routine
*/
-void nfs4_schedule_state_manager(struct nfs_client *clp)
+int nfs4_schedule_state_manager(struct nfs_client *clp)
{
struct task_struct *task;
char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1];
struct rpc_clnt *cl = clp->cl_rpcclient;
+ int ret = 0;
while (cl != cl->cl_parent)
cl = cl->cl_parent;
@@ -1213,7 +1215,8 @@ void nfs4_schedule_state_manager(struct nfs_client *clp)
set_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state);
if (test_and_set_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state) != 0) {
wake_up_var(&clp->cl_state);
- return;
+ ret = -EIO;
+ goto out;
}
set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
__module_get(THIS_MODULE);
@@ -1228,13 +1231,15 @@ void nfs4_schedule_state_manager(struct nfs_client *clp)
rcu_read_unlock();
task = kthread_run(nfs4_run_state_manager, clp, "%s", buf);
if (IS_ERR(task)) {
- printk(KERN_ERR "%s: kthread_run: %ld\n",
- __func__, PTR_ERR(task));
+ ret = PTR_ERR(task);
+ printk(KERN_ERR "%s: kthread_run: %d\n", __func__, ret);
nfs4_clear_state_manager_bit(clp);
clear_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state);
nfs_put_client(clp);
module_put(THIS_MODULE);
}
+out:
+ return ret;
}
/*