When testing nfs4.0 lock, I get WARN_ON message as below,
[ 278.733391] ------------[ cut here ]------------
[ 278.734496] WARNING: CPU: 0 PID: 263 at /root/linux-nfs/net/sunrpc/sched.c:692 rpc_exit_task+0x85/0x90 [sunrpc]()
[ 278.736771] Modules linked in: nfsv4(OE) nfs(OE) nfsd(E) bnep bluetooth ip6t_rpfilter ip6t_REJECT xt_conntrack cfg80211 rfkill ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw btrfs ppdev xfs microcode xor serio_raw libcrc32c pcspkr raid6_pq e1000 parport_pc parport i2c_piix4 i2c_core auth_rpcgss nfs_acl lockd sunrpc(OE) ata_generic pata_acpi [last unloaded: nfsd]
[ 278.751462] CPU: 0 PID: 263 Comm: kworker/0:4 Tainted: G OE 3.16.0-rc2+ #28
[ 278.753364] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/31/2013
[ 278.755710] Workqueue: rpciod rpc_async_schedule [sunrpc]
[ 278.757112] 0000000000000000 00000000f6173352 ffff880072e5fd30 ffffffff816eacfa
[ 278.758811] 0000000000000000 ffff880072e5fd68 ffffffff8108bf3d ffff88005997f180
[ 278.760527] ffff88003ae44830 ffffffffa001a860 ffffffffa001a860 0000000000000000
[ 278.762271] Call Trace:
[ 278.762802] [<ffffffff816eacfa>] dump_stack+0x45/0x56
[ 278.763906] [<ffffffff8108bf3d>] warn_slowpath_common+0x7d/0xa0
[ 278.765419] [<ffffffffa001a860>] ? rpc_destroy_wait_queue+0x20/0x20 [sunrpc]
[ 278.767243] [<ffffffffa001a860>] ? rpc_destroy_wait_queue+0x20/0x20 [sunrpc]
[ 278.768758] [<ffffffff8108c06a>] warn_slowpath_null+0x1a/0x20
[ 278.770080] [<ffffffffa001a8e5>] rpc_exit_task+0x85/0x90 [sunrpc]
[ 278.771439] [<ffffffffa001b204>] __rpc_execute+0x94/0x420 [sunrpc]
[ 278.772829] [<ffffffffa001b5b6>] rpc_async_schedule+0x26/0x30 [sunrpc]
[ 278.774276] [<ffffffff810a7f95>] process_one_work+0x175/0x430
[ 278.775573] [<ffffffff810a866d>] worker_thread+0x11d/0x530
[ 278.776824] [<ffffffff810a8550>] ? rescuer_thread+0x300/0x300
[ 278.778069] [<ffffffff810aee18>] kthread+0xd8/0xf0
[ 278.779114] [<ffffffff810aed40>] ? insert_kthread_work+0x40/0x40
[ 278.780448] [<ffffffff816f22bc>] ret_from_fork+0x7c/0xb0
[ 278.781621] [<ffffffff810aed40>] ? insert_kthread_work+0x40/0x40
[ 278.782972] ---[ end trace 3350394592832e42 ]---
task1:
--> call_decode
--> rpc_exit_task (-10011)
--> nfs4_release_lockowner_done
--> rpc_restart_call_prepare
task->tk_action = call_start;
task2:
--> rpc_shutdown_client
--> rpc_killall_tasks
rovr->tk_flags |= RPC_TASK_KILLED; (set task1 to KILLED)
task1:
--> rpc_exit_task
WARN_ON(RPC_ASSASSINATED(task));
Signed-off-by: Kinglong Mee <[email protected]>
---
net/sunrpc/sched.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
index c0365c1..ed0f8e5 100644
--- a/net/sunrpc/sched.c
+++ b/net/sunrpc/sched.c
@@ -689,7 +689,9 @@ void rpc_exit_task(struct rpc_task *task)
if (task->tk_ops->rpc_call_done != NULL) {
task->tk_ops->rpc_call_done(task, task->tk_calldata);
if (task->tk_action != NULL) {
- WARN_ON(RPC_ASSASSINATED(task));
+ if (RPC_ASSASSINATED(task))
+ printk(KERN_ERR "RPC: dead task tried to"
+ " walk away.\n");
/* Always release the RPC slot and buffer memory */
xprt_release(task);
rpc_reset_task_statistics(task);
--
1.9.3