3.10.y regression caused by: lockd: ensure we tear down any live sockets when socket creation fails during lockd_up

DISCUSSION Nikita Yushchenko 4 participants 5 messages Jun 20, 2014 – Aug 29, 2014

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Nikita Yushchenko

author

2014-06-20 11:14 UTC #0 lore raw

With current 3.10.y, if kernel is booted with init=/bin/sh and then nfs mount is attempted (without portmap or rpcbind running) using busybox mount, following OOPS happen:

# mount -t nfs 10.30.130.21:/opt /mnt
svc: failed to register lockdv1 RPC service (errno 111).
lockd_up: makesock failed, error=-111
Unable to handle kernel paging request for data at address 0x00000030
Faulting instruction address: 0xc055e65c
Oops: Kernel access of bad area, sig: 11 [#1]
MPC85xx CDS
Modules linked in:
CPU: 0 PID: 1338 Comm: mount Not tainted 3.10.44.cge #117
task: cf29cea0 ti: cf35c000 task.ti: cf35c000
NIP: c055e65c LR: c0566490 CTR: c055e648
REGS: cf35dad0 TRAP: 0300   Not tainted  (3.10.44.cge)
MSR: 00029000 <CE,EE,ME>  CR: 22442488  XER: 20000000
DEAR: 00000030, ESR: 00000000

GPR00: c05606f4 cf35db80 cf29cea0 cf0ded80 cf0dedb8 00000001 1dec3086 00000000
GPR08: 00000000 c07b1640 00000007 1dec3086 22442482 100b9758 00000000 10090ae8
GPR16: 00000000 000186a5 00000000 00000000 100c3018 bfa46edc 100b0000 bfa46ef0
GPR24: cf386ae0 c07834f0 00000000 c0565f88 00000001 cf0dedb8 00000000 cf0ded80 NIP [c055e65c] call_start+0x14/0x34
LR [c0566490] __rpc_execute+0x70/0x250

Call Trace:

[cf35db80] [00000080] 0x80 (unreliable) [cf35dbb0] [c05606f4] rpc_run_task+0x9c/0xc4 [cf35dbc0] [c0560840] rpc_call_sync+0x50/0xb8 [cf35dbf0] [c056ee90] rpcb_register_call+0x54/0x84 [cf35dc10] [c056f24c] rpcb_register+0xf8/0x10c [cf35dc70] [c0569e18] svc_unregister.isra.23+0x100/0x108 [cf35dc90] [c0569e38] svc_rpcb_cleanup+0x18/0x30 [cf35dca0] [c0198c5c] lockd_up+0x1dc/0x2e0 [cf35dcd0] [c0195348] nlmclnt_init+0x2c/0xc8 [cf35dcf0] [c015bb5c] nfs_start_lockd+0x98/0xec [cf35dd20] [c015ce6c] nfs_create_server+0x1e8/0x3f4 [cf35dd90] [c0171590] nfs3_create_server+0x10/0x44 [cf35dda0] [c016528c] nfs_try_mount+0x158/0x1e4 [cf35de20] [c01670d0] nfs_fs_mount+0x434/0x8c8 [cf35de70] [c00cd3bc] mount_fs+0x20/0xbc [cf35de90] [c00e4f88] vfs_kern_mount+0x50/0x104 [cf35dec0] [c00e6e0c] do_mount+0x1d0/0x8e0 [cf35df10] [c00e75ac] SyS_mount+0x90/0xd0 [cf35df40] [c000ccf4] ret_from_syscall+0x0/0x3c --- Exception: c01 at 0xff2acc4

    LR = 0x10048ab8
Instruction dump:
3d20c056 3929e648 91230028 38600001 4e800020 38600000 4e800020 81230014 
8103000c 81490014 394a0001 91490014 <81280030> 81490018 394a0001 91490018 
---[ end trace 033b5b4715cb5452 ]---

This does not happen if

commit 72a6e594497032bd911bd187a88fae4b4473abb3

Author: Jeff Layton <[email protected]>
Date:   Tue Mar 25 11:55:26 2014 -0700

lockd: ensure we tear down any live sockets when socket creation fails during lockd_up

commit 679b033df48422191c4cac52b610d9980e019f9b upstream.

is reverted:

# mount -t nfs 10.30.130.21:/opt /mnt
svc: failed to register lockdv1 RPC service (errno 111).
lockd_up: makesock failed, error=-111
mount: mounting 10.30.130.21:/opt on /mnt failed: Connection refused
#

Physical reason of the OOPS is that:

- addition of svc_shutdown_net() call to error path of make_socks() causes double call of svc_rpcb_cleanup():
- first call is from within svc_shutdown_net(), because serv->sv_shutdown
points to svc_rpcb_cleanup() at this time,
- immediately followed by second call from lockd_up_net()'s error path

- when second svc_rpcb_cleanup() is executed, then at
svc_unregister() -> __svc_unregister() -> rpcb_register() -> rpcb_register_call()
call path, rpcb_register_call() is called with clnt=NULL.

Greg Kroah-Hartman

maintainer

2014-07-07 22:23 UTC #1 lore raw

Quoted 80 lines · Nikita Yushchenko

With current 3.10.y, if kernel is booted with init=/bin/sh and then nfs mount is attempted (without portmap or rpcbind running) using busybox mount, following OOPS happen:
# mount -t nfs 10.30.130.21:/opt /mnt
svc: failed to register lockdv1 RPC service (errno 111).
lockd_up: makesock failed, error=-111
Unable to handle kernel paging request for data at address 0x00000030
Faulting instruction address: 0xc055e65c
Oops: Kernel access of bad area, sig: 11 [#1]
MPC85xx CDS
Modules linked in:
CPU: 0 PID: 1338 Comm: mount Not tainted 3.10.44.cge #117
task: cf29cea0 ti: cf35c000 task.ti: cf35c000
NIP: c055e65c LR: c0566490 CTR: c055e648
REGS: cf35dad0 TRAP: 0300   Not tainted  (3.10.44.cge)
MSR: 00029000 <CE,EE,ME>  CR: 22442488  XER: 20000000
DEAR: 00000030, ESR: 00000000
GPR00: c05606f4 cf35db80 cf29cea0 cf0ded80 cf0dedb8 00000001 1dec3086 00000000
GPR08: 00000000 c07b1640 00000007 1dec3086 22442482 100b9758 00000000 10090ae8
GPR16: 00000000 000186a5 00000000 00000000 100c3018 bfa46edc 100b0000 bfa46ef0
GPR24: cf386ae0 c07834f0 00000000 c0565f88 00000001 cf0dedb8 00000000 cf0ded80 NIP [c055e65c] call_start+0x14/0x34
LR [c0566490] __rpc_execute+0x70/0x250
Call Trace:
[cf35db80] [00000080] 0x80 (unreliable) [cf35dbb0] [c05606f4] rpc_run_task+0x9c/0xc4 [cf35dbc0] [c0560840] rpc_call_sync+0x50/0xb8 [cf35dbf0] [c056ee90] rpcb_register_call+0x54/0x84 [cf35dc10] [c056f24c] rpcb_register+0xf8/0x10c [cf35dc70] [c0569e18] svc_unregister.isra.23+0x100/0x108 [cf35dc90] [c0569e38] svc_rpcb_cleanup+0x18/0x30 [cf35dca0] [c0198c5c] lockd_up+0x1dc/0x2e0 [cf35dcd0] [c0195348] nlmclnt_init+0x2c/0xc8 [cf35dcf0] [c015bb5c] nfs_start_lockd+0x98/0xec [cf35dd20] [c015ce6c] nfs_create_server+0x1e8/0x3f4 [cf35dd90] [c0171590] nfs3_create_server+0x10/0x44 [cf35dda0] [c016528c] nfs_try_mount+0x158/0x1e4 [cf35de20] [c01670d0] nfs_fs_mount+0x434/0x8c8 [cf35de70] [c00cd3bc] mount_fs+0x20/0xbc [cf35de90] [c00e4f88] vfs_kern_mount+0x50/0x104 [cf35dec0] [c00e6e0c] do_mount+0x1d0/0x8e0 [cf35df10] [c00e75ac] SyS_mount+0x90/0xd0 [cf35df40] [c000ccf4] ret_from_syscall+0x0/0x3c --- Exception: c01 at 0xff2acc4
    LR = 0x10048ab8
Instruction dump:
3d20c056 3929e648 91230028 38600001 4e800020 38600000 4e800020 81230014 
8103000c 81490014 394a0001 91490014 <81280030> 81490018 394a0001 91490018 
---[ end trace 033b5b4715cb5452 ]---
This does not happen if
commit 72a6e594497032bd911bd187a88fae4b4473abb3
Author: Jeff Layton <[email protected]>
Date:   Tue Mar 25 11:55:26 2014 -0700
lockd: ensure we tear down any live sockets when socket creation fails during lockd_up
commit 679b033df48422191c4cac52b610d9980e019f9b upstream.
is reverted:
# mount -t nfs 10.30.130.21:/opt /mnt
svc: failed to register lockdv1 RPC service (errno 111).
lockd_up: makesock failed, error=-111
mount: mounting 10.30.130.21:/opt on /mnt failed: Connection refused
#
Physical reason of the OOPS is that:
- addition of svc_shutdown_net() call to error path of make_socks() causes double call of svc_rpcb_cleanup():
- first call is from within svc_shutdown_net(), because serv->sv_shutdown
points to svc_rpcb_cleanup() at this time,
- immediately followed by second call from lockd_up_net()'s error path

Quoted 3 lines

- when second svc_rpcb_cleanup() is executed, then at
svc_unregister() -> __svc_unregister() -> rpcb_register() -> rpcb_register_call()
call path, rpcb_register_call() is called with clnt=NULL.

So, Jeff, what should I do here? Drop this patch from 3.10? Add something else to fix it up? Something else entirely?

thanks,

greg k-h

Nikita Yushchenko

author

2014-07-22 13:59 UTC #2 lore raw

Quoted 80 lines

Quoted 80 lines
With current 3.10.y, if kernel is booted with init=/bin/sh and then nfs mount is attempted (without portmap or rpcbind running) using busybox mount, following OOPS happen:
# mount -t nfs 10.30.130.21:/opt /mnt
svc: failed to register lockdv1 RPC service (errno 111).
lockd_up: makesock failed, error=-111
Unable to handle kernel paging request for data at address 0x00000030
Faulting instruction address: 0xc055e65c
Oops: Kernel access of bad area, sig: 11 [#1]
MPC85xx CDS
Modules linked in:
CPU: 0 PID: 1338 Comm: mount Not tainted 3.10.44.cge #117
task: cf29cea0 ti: cf35c000 task.ti: cf35c000
NIP: c055e65c LR: c0566490 CTR: c055e648
REGS: cf35dad0 TRAP: 0300   Not tainted  (3.10.44.cge)
MSR: 00029000 <CE,EE,ME>  CR: 22442488  XER: 20000000
DEAR: 00000030, ESR: 00000000
GPR00: c05606f4 cf35db80 cf29cea0 cf0ded80 cf0dedb8 00000001 1dec3086 00000000
GPR08: 00000000 c07b1640 00000007 1dec3086 22442482 100b9758 00000000 10090ae8
GPR16: 00000000 000186a5 00000000 00000000 100c3018 bfa46edc 100b0000 bfa46ef0
GPR24: cf386ae0 c07834f0 00000000 c0565f88 00000001 cf0dedb8 00000000 cf0ded80 NIP [c055e65c] call_start+0x14/0x34
LR [c0566490] __rpc_execute+0x70/0x250
Call Trace:
[cf35db80] [00000080] 0x80 (unreliable) [cf35dbb0] [c05606f4] rpc_run_task+0x9c/0xc4 [cf35dbc0] [c0560840] rpc_call_sync+0x50/0xb8 [cf35dbf0] [c056ee90] rpcb_register_call+0x54/0x84 [cf35dc10] [c056f24c] rpcb_register+0xf8/0x10c [cf35dc70] [c0569e18] svc_unregister.isra.23+0x100/0x108 [cf35dc90] [c0569e38] svc_rpcb_cleanup+0x18/0x30 [cf35dca0] [c0198c5c] lockd_up+0x1dc/0x2e0 [cf35dcd0] [c0195348] nlmclnt_init+0x2c/0xc8 [cf35dcf0] [c015bb5c] nfs_start_lockd+0x98/0xec [cf35dd20] [c015ce6c] nfs_create_server+0x1e8/0x3f4 [cf35dd90] [c0171590] nfs3_create_server+0x10/0x44 [cf35dda0] [c016528c] nfs_try_mount+0x158/0x1e4 [cf35de20] [c01670d0] nfs_fs_mount+0x434/0x8c8 [cf35de70] [c00cd3bc] mount_fs+0x20/0xbc [cf35de90] [c00e4f88] vfs_kern_mount+0x50/0x104 [cf35dec0] [c00e6e0c] do_mount+0x1d0/0x8e0 [cf35df10] [c00e75ac] SyS_mount+0x90/0xd0 [cf35df40] [c000ccf4] ret_from_syscall+0x0/0x3c --- Exception: c01 at 0xff2acc4
     LR = 0x10048ab8
Instruction dump:
3d20c056 3929e648 91230028 38600001 4e800020 38600000 4e800020 81230014
8103000c 81490014 394a0001 91490014 <81280030> 81490018 394a0001 91490018
---[ end trace 033b5b4715cb5452 ]---
This does not happen if
commit 72a6e594497032bd911bd187a88fae4b4473abb3
Author: Jeff Layton <[email protected]>
Date:   Tue Mar 25 11:55:26 2014 -0700
lockd: ensure we tear down any live sockets when socket creation fails during lockd_up
commit 679b033df48422191c4cac52b610d9980e019f9b upstream.
is reverted:
# mount -t nfs 10.30.130.21:/opt /mnt
svc: failed to register lockdv1 RPC service (errno 111).
lockd_up: makesock failed, error=-111
mount: mounting 10.30.130.21:/opt on /mnt failed: Connection refused
#
Physical reason of the OOPS is that:
- addition of svc_shutdown_net() call to error path of make_socks() causes double call of svc_rpcb_cleanup():
- first call is from within svc_shutdown_net(), because serv->sv_shutdown
points to svc_rpcb_cleanup() at this time,
- immediately followed by second call from lockd_up_net()'s error path

Quoted 6 lines

Quoted 3 lines
- when second svc_rpcb_cleanup() is executed, then at
svc_unregister() -> __svc_unregister() -> rpcb_register() -> rpcb_register_call()
call path, rpcb_register_call() is called with clnt=NULL.
So, Jeff, what should I do here? Drop this patch from 3.10? Add something else to fix it up? Something else entirely?

Problem is still there with 3.10.49

sh-4.2# /tmp/mount 10.150.42.24:/opt /mnt
svc: failed to register lockdv1 RPC service (errno 111).
lockd_up: makesock failed, error=-111

Unable to handle kernel paging request for data at address 0x00000038           
Faulting instruction address: 0xc055bb5c                                        
Oops: Kernel access of bad area, sig: 11 [#1]                                   
PREEMPT SMP NR_CPUS=2 MPC8572 DS                                                
Modules linked in:                                                              
CPU: 0 PID: 1315 Comm: mount Not tainted 3.10.49.cge #123                       
task: efb1f300 ti: c7ab0000 task.ti: c7ab0000                                   
NIP: c055bb5c LR: c0564df4 CTR: c055bb48                                        
REGS: c7ab1aa0 TRAP: 0300   Not tainted  (3.10.49.cge)                          
MSR: 00029000 <CE,EE,ME>  CR: 22442482  XER: 20000000                           
DEAR: 00000038, ESR: 00000000

GPR00: c055e124 c7ab1b50 efb1f300 ef8f8d80 ef8f8db8 00000001 5d3119ef 00000000
GPR08: 00000000 c075e534 00000007 21964fef 22442482 100b9758 00000000 10090ae8
GPR16: 00000000 000186a5 00000000 00000000 101e3018 c0564814 00000001 ef8f8db8
GPR24: c0760000 00000000 c7ab0000 c055bb48 00000000 c055bb48 c7ab1bb8 ef8f8d80 NIP [c055bb5c] call_start+0x14/0x34
LR [c0564df4] __rpc_execute+0x90/0x388

Call Trace:                                                                     
[c7ab1b50] [c00879e8] ktime_get+0x154/0x170 (unreliable)                        
[c7ab1ba0] [c055e124] rpc_run_task+0x9c/0xc4                                    
[c7ab1bb0] [c055e270] rpc_call_sync+0x50/0xb8                                   
[c7ab1be0] [c056e1e4] rpcb_register_call+0x54/0x84
[c7ab1c00] [c056e680] rpcb_register+0x108/0x11c
[c7ab1c70] [c0568d08] svc_unregister+0x110/0x118
[c7ab1c90] [c0568d28] svc_rpcb_cleanup+0x18/0x30
[c7ab1ca0] [c02803c4] lockd_up+0x1e4/0x2e8
[c7ab1cd0] [c027c8fc] nlmclnt_init+0x2c/0xc8
[c7ab1cf0] [c024b3bc] nfs_start_lockd+0x98/0xec
[c7ab1d20] [c024c744] nfs_create_server+0x1e8/0x3f4
[c7ab1d90] [c02622dc] nfs3_create_server+0x14/0x40
[c7ab1da0] [c0255558] nfs_try_mount+0x158/0x1e4
[c7ab1e20] [c0257420] nfs_fs_mount+0x438/0x8cc
[c7ab1e70] [c0140e3c] mount_fs+0x20/0xbc
[c7ab1e90] [c015b7a8] vfs_kern_mount+0x50/0x104
[c7ab1ec0] [c015dad0] do_mount+0x1d0/0x8ec
[c7ab1f10] [c015e27c] SyS_mount+0x90/0xd0
[c7ab1f40] [c000ee74] ret_from_syscall+0x0/0x3c
--- Exception: c01 at 0xff0ada0
    LR = 0x10048ab8
Instruction dump:
3d20c056 3929bb48 91230028 38600001 4e800020 38600000 4e800020 81230014 
8103000c 81490014 394a0001 91490014 <81280038> 81490018 394a0001 91490018 
---[ end trace 17b77871713e3175 ]---

J. Bruce Fields

2014-08-29 20:25 UTC #3 lore raw

In reply to Greg Kroah-Hartman

Quoted 81 lines · Greg Kroah-Hartman

Quoted 80 lines · Nikita Yushchenko
With current 3.10.y, if kernel is booted with init=/bin/sh and then nfs mount is attempted (without portmap or rpcbind running) using busybox mount, following OOPS happen:
# mount -t nfs 10.30.130.21:/opt /mnt
svc: failed to register lockdv1 RPC service (errno 111).
lockd_up: makesock failed, error=-111
Unable to handle kernel paging request for data at address 0x00000030
Faulting instruction address: 0xc055e65c
Oops: Kernel access of bad area, sig: 11 [#1]
MPC85xx CDS
Modules linked in:
CPU: 0 PID: 1338 Comm: mount Not tainted 3.10.44.cge #117
task: cf29cea0 ti: cf35c000 task.ti: cf35c000
NIP: c055e65c LR: c0566490 CTR: c055e648
REGS: cf35dad0 TRAP: 0300   Not tainted  (3.10.44.cge)
MSR: 00029000 <CE,EE,ME>  CR: 22442488  XER: 20000000
DEAR: 00000030, ESR: 00000000
GPR00: c05606f4 cf35db80 cf29cea0 cf0ded80 cf0dedb8 00000001 1dec3086 00000000
GPR08: 00000000 c07b1640 00000007 1dec3086 22442482 100b9758 00000000 10090ae8
GPR16: 00000000 000186a5 00000000 00000000 100c3018 bfa46edc 100b0000 bfa46ef0
GPR24: cf386ae0 c07834f0 00000000 c0565f88 00000001 cf0dedb8 00000000 cf0ded80 NIP [c055e65c] call_start+0x14/0x34
LR [c0566490] __rpc_execute+0x70/0x250
Call Trace:
[cf35db80] [00000080] 0x80 (unreliable) [cf35dbb0] [c05606f4] rpc_run_task+0x9c/0xc4 [cf35dbc0] [c0560840] rpc_call_sync+0x50/0xb8 [cf35dbf0] [c056ee90] rpcb_register_call+0x54/0x84 [cf35dc10] [c056f24c] rpcb_register+0xf8/0x10c [cf35dc70] [c0569e18] svc_unregister.isra.23+0x100/0x108 [cf35dc90] [c0569e38] svc_rpcb_cleanup+0x18/0x30 [cf35dca0] [c0198c5c] lockd_up+0x1dc/0x2e0 [cf35dcd0] [c0195348] nlmclnt_init+0x2c/0xc8 [cf35dcf0] [c015bb5c] nfs_start_lockd+0x98/0xec [cf35dd20] [c015ce6c] nfs_create_server+0x1e8/0x3f4 [cf35dd90] [c0171590] nfs3_create_server+0x10/0x44 [cf35dda0] [c016528c] nfs_try_mount+0x158/0x1e4 [cf35de20] [c01670d0] nfs_fs_mount+0x434/0x8c8 [cf35de70] [c00cd3bc] mount_fs+0x20/0xbc [cf35de90] [c00e4f88] vfs_kern_mount+0x50/0x104 [cf35dec0] [c00e6e0c] do_mount+0x1d0/0x8e0 [cf35df10] [c00e75ac] SyS_mount+0x90/0xd0 [cf35df40] [c000ccf4] ret_from_syscall+0x0/0x3c --- Exception: c01 at 0xff2acc4
    LR = 0x10048ab8
Instruction dump:
3d20c056 3929e648 91230028 38600001 4e800020 38600000 4e800020 81230014 
8103000c 81490014 394a0001 91490014 <81280030> 81490018 394a0001 91490018 
---[ end trace 033b5b4715cb5452 ]---
This does not happen if
commit 72a6e594497032bd911bd187a88fae4b4473abb3
Author: Jeff Layton <[email protected]>
Date:   Tue Mar 25 11:55:26 2014 -0700
lockd: ensure we tear down any live sockets when socket creation fails during lockd_up
commit 679b033df48422191c4cac52b610d9980e019f9b upstream.
is reverted:
# mount -t nfs 10.30.130.21:/opt /mnt
svc: failed to register lockdv1 RPC service (errno 111).
lockd_up: makesock failed, error=-111
mount: mounting 10.30.130.21:/opt on /mnt failed: Connection refused
#
Physical reason of the OOPS is that:
- addition of svc_shutdown_net() call to error path of make_socks() causes double call of svc_rpcb_cleanup():
- first call is from within svc_shutdown_net(), because serv->sv_shutdown
points to svc_rpcb_cleanup() at this time,
- immediately followed by second call from lockd_up_net()'s error path

Quoted 6 lines

Quoted 3 lines
- when second svc_rpcb_cleanup() is executed, then at
svc_unregister() -> __svc_unregister() -> rpcb_register() -> rpcb_register_call()
call path, rpcb_register_call() is called with clnt=NULL.
So, Jeff, what should I do here? Drop this patch from 3.10? Add something else to fix it up? Something else entirely?

Sorry this got ignored. Adding more useful addressess....

So looks like the new svc_shutdown_net made lockd_up_net's cleanup redundant, and just removing it might do the job?

--b.

fs/lockd/svc.c +1 -3

index 673668a9eec1..685e953c5103 100644
@@ -253,13 +253,11 @@ static int lockd_up_net(struct svc_serv *serv, struct net *net)
 
 	error = make_socks(serv, net);
 	if (error < 0)
-		goto err_socks;
+		goto err_bind;
 	set_grace_period(net);
 	dprintk("lockd_up_net: per-net data created; net=%p\n", net);
 	return 0;
 
-err_socks:
-	svc_rpcb_cleanup(serv, net);
 err_bind:
 	ln->nlmsvc_users--;
 	return error;

Jeff Layton

Acked-by

2014-08-29 21:22 UTC #4 lore raw

Quoted 105 lines · On Fri, 29 Aug 2014 16:25:33 -0400 "J. Bruce Fields" <[email protected]> wrote:

Quoted 81 lines · Greg Kroah-Hartman
Quoted 80 lines · Nikita Yushchenko
With current 3.10.y, if kernel is booted with init=/bin/sh and then nfs mount is attempted (without portmap or rpcbind running) using busybox mount, following OOPS happen:
# mount -t nfs 10.30.130.21:/opt /mnt
svc: failed to register lockdv1 RPC service (errno 111).
lockd_up: makesock failed, error=-111
Unable to handle kernel paging request for data at address 0x00000030
Faulting instruction address: 0xc055e65c
Oops: Kernel access of bad area, sig: 11 [#1]
MPC85xx CDS
Modules linked in:
CPU: 0 PID: 1338 Comm: mount Not tainted 3.10.44.cge #117
task: cf29cea0 ti: cf35c000 task.ti: cf35c000
NIP: c055e65c LR: c0566490 CTR: c055e648
REGS: cf35dad0 TRAP: 0300   Not tainted  (3.10.44.cge)
MSR: 00029000 <CE,EE,ME>  CR: 22442488  XER: 20000000
DEAR: 00000030, ESR: 00000000
GPR00: c05606f4 cf35db80 cf29cea0 cf0ded80 cf0dedb8 00000001 1dec3086 00000000
GPR08: 00000000 c07b1640 00000007 1dec3086 22442482 100b9758 00000000 10090ae8
GPR16: 00000000 000186a5 00000000 00000000 100c3018 bfa46edc 100b0000 bfa46ef0
GPR24: cf386ae0 c07834f0 00000000 c0565f88 00000001 cf0dedb8 00000000 cf0ded80 NIP [c055e65c] call_start+0x14/0x34
LR [c0566490] __rpc_execute+0x70/0x250
Call Trace:
[cf35db80] [00000080] 0x80 (unreliable) [cf35dbb0] [c05606f4] rpc_run_task+0x9c/0xc4 [cf35dbc0] [c0560840] rpc_call_sync+0x50/0xb8 [cf35dbf0] [c056ee90] rpcb_register_call+0x54/0x84 [cf35dc10] [c056f24c] rpcb_register+0xf8/0x10c [cf35dc70] [c0569e18] svc_unregister.isra.23+0x100/0x108 [cf35dc90] [c0569e38] svc_rpcb_cleanup+0x18/0x30 [cf35dca0] [c0198c5c] lockd_up+0x1dc/0x2e0 [cf35dcd0] [c0195348] nlmclnt_init+0x2c/0xc8 [cf35dcf0] [c015bb5c] nfs_start_lockd+0x98/0xec [cf35dd20] [c015ce6c] nfs_create_server+0x1e8/0x3f4 [cf35dd90] [c0171590] nfs3_create_server+0x10/0x44 [cf35dda0] [c016528c] nfs_try_mount+0x158/0x1e4 [cf35de20] [c01670d0] nfs_fs_mount+0x434/0x8c8 [cf35de70] [c00cd3bc] mount_fs+0x20/0xbc [cf35de90] [c00e4f88] vfs_kern_mount+0x50/0x104 [cf35dec0] [c00e6e0c] do_mount+0x1d0/0x8e0 [cf35df10] [c00e75ac] SyS_mount+0x90/0xd0 [cf35df40] [c000ccf4] ret_from_syscall+0x0/0x3c --- Exception: c01 at 0xff2acc4
    LR = 0x10048ab8
Instruction dump:
3d20c056 3929e648 91230028 38600001 4e800020 38600000 4e800020 81230014 
8103000c 81490014 394a0001 91490014 <81280030> 81490018 394a0001 91490018 
---[ end trace 033b5b4715cb5452 ]---
This does not happen if
commit 72a6e594497032bd911bd187a88fae4b4473abb3
Author: Jeff Layton <[email protected]>
Date:   Tue Mar 25 11:55:26 2014 -0700
lockd: ensure we tear down any live sockets when socket creation fails during lockd_up
commit 679b033df48422191c4cac52b610d9980e019f9b upstream.
is reverted:
# mount -t nfs 10.30.130.21:/opt /mnt
svc: failed to register lockdv1 RPC service (errno 111).
lockd_up: makesock failed, error=-111
mount: mounting 10.30.130.21:/opt on /mnt failed: Connection refused
#
Physical reason of the OOPS is that:
- addition of svc_shutdown_net() call to error path of make_socks() causes double call of svc_rpcb_cleanup():
- first call is from within svc_shutdown_net(), because serv->sv_shutdown
points to svc_rpcb_cleanup() at this time,
- immediately followed by second call from lockd_up_net()'s error path
Quoted 6 lines
Quoted 3 lines
- when second svc_rpcb_cleanup() is executed, then at
svc_unregister() -> __svc_unregister() -> rpcb_register() -> rpcb_register_call()
call path, rpcb_register_call() is called with clnt=NULL.
So, Jeff, what should I do here? Drop this patch from 3.10? Add something else to fix it up? Something else entirely?
Sorry this got ignored. Adding more useful addressess....
So looks like the new svc_shutdown_net made lockd_up_net's cleanup redundant, and just removing it might do the job?
--b.
fs/lockd/svc.c +0 -1
index 673668a9eec1..685e953c5103 100644
@@ -253,13 +253,11 @@ static int lockd_up_net(struct svc_serv *serv, struct net *net)
 
 	error = make_socks(serv, net);
 	if (error < 0)
-		goto err_socks;

fs/lockd/svc.c static int lockd_up_net(struct svc_serv *serv, struct net *net) · line 263

Quoted 10 lines

fs/lockd/svc.c +1 -2

+		goto err_bind;
 	set_grace_period(net);
 	dprintk("lockd_up_net: per-net data created; net=%p\n", net);
 	return 0;
 
-err_socks:
-	svc_rpcb_cleanup(serv, net);
 err_bind:
 	ln->nlmsvc_users--;
 	return error;

Oof -- sorry I missed this. Must have gotten lost in the shuffle with my email address change...

Yeah, that patch looks correct to me. I do wish the whole svc setup/shutdown codepath weren't so godawful complicated, but that's not a trivial thing to untangle at this point (particularly not in the context of -stable).

Acked-by Jeff Layton <[email protected]>