> On Nov 30, 2018, at 1:40 PM, Trond Myklebust <trondmy@xxxxxxxxxxxxxxx> wrote:
>
> On Fri, 2018-11-30 at 12:08 -0500, Chuck Lever wrote:
>> Hi-
>>
>> I'm testing krb5/krb5i/krb5p with stock v4.20-rc4 and NFS/TCP.
>> The workload is synthetic:
>>
>> /home/cel/bin/iozone -M -+u -i0 -i1 -s1g -r8k -t16 -c
>>
>> The client is a 12-core Xeon system.
>>
>>
>> I'm seeing all kinds of symptoms:
>>
>> - memory leaks: bvec and enc_pages are leaking
>>
>> - EBADMSG is reported to user space
>>
>> - data corruption
>>
>> - connect deadlocks resulting in a mount hang
>>
>> - invalid soft IRQ receive buffer warnings
>>
>
> Does the following patch help?
With this patch applied I am able to reproduce at least the
soft IRQ warnings and the connect deadlock. There is possibly
more than one bug.
I've found and fixed the enc_pages leak. Patch forthcoming.
> 8<----------------------------------------------
> From 8ff4cd9f0f6912e14f657371b6b7eecf6d2091ee Mon Sep 17 00:00:00 2001
> From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
> Date: Fri, 30 Nov 2018 12:48:47 -0500
> Subject: [PATCH] SUNRPC: call_connect_status() must handle tasks that got
> transmitted
>
> If a task failed to get the write lock in the call to xprt_connect(), then
> it will be queued on xprt->sending. In that case, it is possible for it
> to get transmitted before the call to call_connect_status(), in which
> case it needs to be handled by call_transmit_status() instead.
>
> Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
> ---
> net/sunrpc/clnt.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
> index ae3b8145da35..e35d642558e7 100644
> --- a/net/sunrpc/clnt.c
> +++ b/net/sunrpc/clnt.c
> @@ -1915,6 +1915,13 @@ call_connect_status(struct rpc_task *task)
> struct rpc_clnt *clnt = task->tk_client;
> int status = task->tk_status;
>
> + /* Check if the task was already transmitted */
> + if (!test_bit(RPC_TASK_NEED_XMIT, &task->tk_runstate)) {
> + xprt_end_transmit(task);
> + task->tk_action = call_transmit_status;
> + return;
> + }
> +
> dprint_status(task);
>
> trace_rpc_connect_status(task);
> --
> 2.19.2
>
> --
> Trond Myklebust
> Linux NFS client maintainer, Hammerspace
> trond.myklebust@xxxxxxxxxxxxxxx
--
Chuck Lever
