The patch below does not apply to the 3.18-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 3944369db701f075092357b511fd9f5755771585 Mon Sep 17 00:00:00 2001
From: Anna Schumaker Anna.Schumaker@Netapp.com Date: Wed, 1 Nov 2017 15:48:43 -0400 Subject: [PATCH] NFS: Avoid RCU usage in tracepoints
There isn't an obvious way to acquire and release the RCU lock during a tracepoint, so we can't use the rpc_peeraddr2str() function here. Instead, rely on the client's cl_hostname, which should have similar enough information without needing an rcu_dereference().
Reported-by: Dave Jones davej@codemonkey.org.uk Cc: stable@vger.kernel.org # v3.12 Signed-off-by: Anna Schumaker Anna.Schumaker@Netapp.com
diff --git a/fs/nfs/nfs4trace.h b/fs/nfs/nfs4trace.h index be1da19c65d6..7a5588c25f70 100644 --- a/fs/nfs/nfs4trace.h +++ b/fs/nfs/nfs4trace.h @@ -201,17 +201,13 @@ DECLARE_EVENT_CLASS(nfs4_clientid_event, TP_ARGS(clp, error),
TP_STRUCT__entry( - __string(dstaddr, - rpc_peeraddr2str(clp->cl_rpcclient, - RPC_DISPLAY_ADDR)) + __string(dstaddr, clp->cl_hostname) __field(int, error) ),
TP_fast_assign( __entry->error = error; - __assign_str(dstaddr, - rpc_peeraddr2str(clp->cl_rpcclient, - RPC_DISPLAY_ADDR)); + __assign_str(dstaddr, clp->cl_hostname); ),
TP_printk( @@ -1132,9 +1128,7 @@ DECLARE_EVENT_CLASS(nfs4_inode_callback_event, __field(dev_t, dev) __field(u32, fhandle) __field(u64, fileid) - __string(dstaddr, clp ? - rpc_peeraddr2str(clp->cl_rpcclient, - RPC_DISPLAY_ADDR) : "unknown") + __string(dstaddr, clp ? clp->cl_hostname : "unknown") ),
TP_fast_assign( @@ -1147,9 +1141,7 @@ DECLARE_EVENT_CLASS(nfs4_inode_callback_event, __entry->fileid = 0; __entry->dev = 0; } - __assign_str(dstaddr, clp ? - rpc_peeraddr2str(clp->cl_rpcclient, - RPC_DISPLAY_ADDR) : "unknown") + __assign_str(dstaddr, clp ? clp->cl_hostname : "unknown") ),
TP_printk( @@ -1191,9 +1183,7 @@ DECLARE_EVENT_CLASS(nfs4_inode_stateid_callback_event, __field(dev_t, dev) __field(u32, fhandle) __field(u64, fileid) - __string(dstaddr, clp ? - rpc_peeraddr2str(clp->cl_rpcclient, - RPC_DISPLAY_ADDR) : "unknown") + __string(dstaddr, clp ? clp->cl_hostname : "unknown") __field(int, stateid_seq) __field(u32, stateid_hash) ), @@ -1208,9 +1198,7 @@ DECLARE_EVENT_CLASS(nfs4_inode_stateid_callback_event, __entry->fileid = 0; __entry->dev = 0; } - __assign_str(dstaddr, clp ? - rpc_peeraddr2str(clp->cl_rpcclient, - RPC_DISPLAY_ADDR) : "unknown") + __assign_str(dstaddr, clp ? clp->cl_hostname : "unknown") __entry->stateid_seq = be32_to_cpu(stateid->seqid); __entry->stateid_hash =