2009-10-20 17:44:48

by Terry Loftin

Subject: [PATCH 1/1] nfs: Panic when commit fails

Actually pass the NFS_FILE_SYNC option to the server to avoid a
Panic in nfs_direct_write_complete() when a commit fails.

At the end of an nfs write, if the nfs commit fails, all the writes
will be rescheduled. They are supposed to be rescheduled as NFS_FILE_SYNC
writes, but the rpc_task structure is not completely intialized and so
the option is not passed. When the rescheduled writes complete, the
return indicates that they are NFS_UNSTABLE and we try to do another
commit. This leads to a Panic because the commit data structure pointer
was set to null in the initial (failed) commit attempt.

Signed-off-by: Terry Loftin <[email protected]>
---

diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index e4e089a..1af78ff 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -457,6 +457,7 @@ static void nfs_direct_write_reschedule(struct nfs_direct_req *dreq)
};
struct rpc_task_setup task_setup_data = {
.rpc_client = NFS_CLIENT(inode),
+ .rpc_message = &msg,
.callback_ops = &nfs_write_direct_ops,
.workqueue = nfsiod_workqueue,
.flags = RPC_TASK_ASYNC,

2009-10-20 22:06:27

by Trond Myklebust

Subject: Re: [PATCH 1/1] nfs: Panic when commit fails

On Tue, 2009-10-20 at 11:44 -0600, Terry Loftin wrote:
> Actually pass the NFS_FILE_SYNC option to the server to avoid a
> Panic in nfs_direct_write_complete() when a commit fails.
>
> At the end of an nfs write, if the nfs commit fails, all the writes
> will be rescheduled. They are supposed to be rescheduled as NFS_FILE_SYNC
> writes, but the rpc_task structure is not completely intialized and so
> the option is not passed. When the rescheduled writes complete, the
> return indicates that they are NFS_UNSTABLE and we try to do another
> commit. This leads to a Panic because the commit data structure pointer
> was set to null in the initial (failed) commit attempt.
>
> Signed-off-by: Terry Loftin <[email protected]>
> ---
>
> diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
> index e4e089a..1af78ff 100644
> --- a/fs/nfs/direct.c
> +++ b/fs/nfs/direct.c
> @@ -457,6 +457,7 @@ static void nfs_direct_write_reschedule(struct nfs_direct_req *dreq)
> };
> struct rpc_task_setup task_setup_data = {
> .rpc_client = NFS_CLIENT(inode),
> + .rpc_message = &msg,
> .callback_ops = &nfs_write_direct_ops,
> .workqueue = nfsiod_workqueue,
> .flags = RPC_TASK_ASYNC,

Doh! Well spotted. I'll pass this along into mainline+stable.

Cheers
Trond