> On Oct 30, 2016, at 21:18, Vitaliy Gusev <gusev.vitaliy@xxxxxxxxx> wrote: > > Hi. > > During some tests I’ve seen nfs-client crashes. It was just reading file via NFSv4.1 protocol. > > The panic message is below, fixing patch is attached. Why does this need to be fixed on the client? It looks like a server bug… In any case, the fix you propose is going to leave the client with broken open state. > > ——— > "BUG: unable to handle kernel NULL pointer dereference at 0000000000000090 > "IP: [<ffffffffb049eefc>] _raw_spin_lock+0xc/0x30 > PGD 2a1c067 PUD 29e5067 PMD 0 > Oops: 0002 [#1] SMP > CPU: 1 PID: 3573 Comm: kworker/1:0 Not tainted 4.8.0-26-generic #28-Ubuntu > Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/02/2015 > Workqueue: rpciod rpc_async_schedule [sunrpc] > task: ffffa017cb534740 task.stack: ffffa01782b44000 > RIP: 0010:[<ffffffffb049eefc>] [<ffffffffb049eefc>] _raw_spin_lock+0xc/0x30N^ > RSP: 0018:ffffa01782b47d48 EFLAGS: 00010246 > RAX: 0000000000000000 RBX: ffffa017c735d208 RCX: ffffa01783816c00 > RDX: 0000000000000001 RSI: ffffa017c735d1e0 RDI: 0000000000000090 > RBP: ffffa01782b47d78 R08: ffffa017cec58a00 R09: 0000000000000000 > R10: 0000000000000000 R11: 000000b4098ed036 R12: ffffa01783816c00 > R13: 0000000000000000 R14: 0000000000000090 R15: ffffa017c735d1e0 > FS: 0000000000000000(0000) GS:ffffa017cec40000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000000000090 CR3: 0000000002a0c000 CR4: 00000000001406e0 > Stack: > ffffffffc0836208 ffffa01783816c00 ffffffffc04c9070 ffffffffc04c9070 > 0000000000000000 ffffa01783816c40 ffffa01782b47d88 ffffffffc08362d0 > ffffa01782b47d98 ffffffffc04c9089 ffffa01782b47e00 ffffffffc04cb6fd > > Call Trace: > [<ffffffffc0836208>] ? nfs40_setup_sequence+0x48/0xe0 [nfsv4] > [<ffffffffc08362d0>] nfs4_open_confirm_prepare+0x30/0x40 [nfsv4] > [<ffffffffc04c9089>] rpc_prepare_task+0x19/0x20 [sunrpc] > [<ffffffffc04cb6fd>] __rpc_execute+0x8d/0x420 [sunrpc] > [<ffffffffc04cbaa2>] rpc_async_schedule+0x12/0x20 [sunrpc] > [<ffffffffafc9d61c>] process_one_work+0x1fc/0x4b0 > [<ffffffffafc9d91b>] worker_thread+0x4b/0x500 > [<ffffffffafca3c18>] kthread+0xd8/0xf0 > [<ffffffffb049f29f>] ret_from_fork+0x1f/0x40 > [<ffffffffafca3b40>] ? kthread_create_on_node+0x1e0/0x1e0 > Code: 00 01 00 00 f0 0f c1 37 81 c6 00 01 00 00 40 84 f6 75 01 c3 55 48 89 e5 e8 e2 19 83 ff 5d c3 0f 1f 44 00 00 31 c0 ba 01 00 00 00 <f0> 0f b1 17 85 c0 75 01 c3 55 89 c6 48 89 e5 e8 c0 01 83 ff 66 > "RIP [<ffffffffb049eefc>] _raw_spin_lock+0xc/0x30 > > ——— ��.n��������+%������w��{.n�����{��w���jg��������ݢj����G�������j:+v���w�m������w�������h�����٥