2010-12-14 08:54:45

by Mi Jinlong

[permalink] [raw]
Subject: kernel panic when mount NFSv4

Hi,

When testing NFSv4 at RHEL6 with kernel 2.6.32, I got a kernel panic
at NFS client's __rpc_create_common function.

The panic place is:
rpc_mkpipe
__rpc_lookup_create() <=== find pipefile *idmap*
__rpc_mkpipe() <=== pipefile is *idmap*
__rpc_create_common()
****** BUG_ON(!d_unhashed(dentry)); ****** *panic*

It means that the dentry's d_flags have be set DCACHE_UNHASHED,
but it should not be set here.

Is someone known this bug? or give me some idea?

A reproduce program is append, but it can't reproduce the bug every time.
the export is: "/nfsroot *(rw,no_root_squash,fsid=0,insecure)"

And the panic message is append.

============================================================================
#!/bin/sh

LOOPTOTAL=768
LOOPCOUNT=0
ret=0

while [ $LOOPCOUNT -ne $LOOPTOTAL ]
do
((LOOPCOUNT += 1))
service nfs restart
/usr/sbin/rpc.idmapd
mount -t nfs4 127.0.0.1:/ /mnt|| return 1;
ls -l /var/lib/nfs/rpc_pipefs/nfs/*/
umount /mnt
echo $LOOPCOUNT
done

===============================================================================
Code: af 60 01 00 00 89 fa 89 f0 e8 64 cf 89 f0 e8 5c 7c 64 cf 31 c0 8b 5c 24 10 8b
74 24 14 8b 7c 24 18 8b 6c 24 1c 83 c4 20 c3 <0f> 0b eb fc 8b 46 28 c7 44 24 08 20
de ee f0 c7 44 24 04 56 ea
EIP:[<f0ee92ea>] __rpc_create_common+0x8a/0xc0 [sunrpc] SS:ESP 0068:eccb5d28
---[ end trace 8f5606cd08928ed2]---
Kernel panic - not syncing: Fatal exception
Pid:7131, comm: mount.nfs4 Tainted: G D -------------------2.6.32 #1
Call Trace:
[<c080ad18>] ? panic+0x42/0xed
[<c080e42c>] ? oops_end+0xbc/0xd0
[<c040b090>] ? do_invalid_op+0x0/0x90
[<c040b10f>] ? do_invalid_op+0x7f/0x90
[<f0ee92ea>] ? __rpc_create_common+0x8a/0xc0[sunrpc]
[<f0edc433>] ? rpc_free_task+0x33/0x70[sunrpc]
[<f0ed6508>] ? prc_call_sync+0x48/0x60[sunrpc]
[<f0ed656e>] ? rpc_ping+0x4e/0x60[sunrpc]
[<f0ed6eaf>] ? rpc_create+0x38f/0x4f0[sunrpc]
[<c080d80b>] ? error_code+0x73/0x78
[<f0ee92ea>] ? __rpc_create_common+0x8a/0xc0[sunrpc]
[<c0532bda>] ? d_lookup+0x2a/0x40
[<f0ee94b1>] ? rpc_mkpipe+0x111/0x1b0[sunrpc]
[<f10a59f4>] ? nfs_create_rpc_client+0xb4/0xf0[nfs]
[<f10d6c6d>] ? nfs_fscache_get_client_cookie+0x1d/0x50[nfs]
[<f10d3fcb>] ? nfs_idmap_new+0x7b/0x140[nfs]
[<c05e76aa>] ? strlcpy+0x3a/0x60
[<f10a60ca>] ? nfs4_set_client+0xea/0x2b0[nfs]
[<f10a6d0c>] ? nfs4_create_server+0xac/0x1b0[nfs]
[<c04f1400>] ? krealloc+0x40/0x50
[<f10b0e8b>] ? nfs4_remote_get_sb+0x6b/0x250[nfs]
[<c04f14ec>] ? kstrdup+0x3c/0x60
[<c0520739>] ? vfs_kern_mount+0x69/0x170
[<f10b1a3c>] ? nfs_do_root_mount+0x6c/0xa0[nfs]
[<f10b1b47>] ? nfs4_try_mount+0x37/0xa0[nfs]
[<f10afe6d>] ? nfs4_validate_text_mount_data+-x7d/0xf0[nfs]
[<f10b1c42>] ? nfs4_get_sb+0x92/0x2f0
[<c0520739>] ? vfs_kern_mount+0x69/0x170
[<c05366d2>] ? get_fs_type+0x32/0xb0
[<c052089f>] ? do_kern_mount+0x3f/0xe0
[<c053954f>] ? do_mount+0x2ef/0x740
[<c0537740>] ? copy_mount_options+0xb0/0x120
[<c0539a0e>] ? sys_mount+0x6e/0xa0





2010-12-21 05:34:23

by Mi Jinlong

[permalink] [raw]
Subject: Re: kernel panic when mount NFSv4



Trond Myklebust 写道:
> On Tue, 2010-12-14 at 16:58 +0800, Mi Jinlong wrote:
>> Hi,
>>
>> When testing NFSv4 at RHEL6 with kernel 2.6.32, I got a kernel panic
>> at NFS client's __rpc_create_common function.
>>
>> The panic place is:
>> rpc_mkpipe
>> __rpc_lookup_create() <=== find pipefile *idmap*
>> __rpc_mkpipe() <=== pipefile is *idmap*
>> __rpc_create_common()
>> ****** BUG_ON(!d_unhashed(dentry)); ****** *panic*
>>
>> It means that the dentry's d_flags have be set DCACHE_UNHASHED,
>> but it should not be set here.
>>
>> Is someone known this bug? or give me some idea?
>>
>> A reproduce program is append, but it can't reproduce the bug every time.
>> the export is: "/nfsroot *(rw,no_root_squash,fsid=0,insecure)"
>>
>> And the panic message is append.
>>
>> ============================================================================
>> #!/bin/sh
>>
>> LOOPTOTAL=768
>> LOOPCOUNT=0
>> ret=0
>>
>> while [ $LOOPCOUNT -ne $LOOPTOTAL ]
>> do
>> ((LOOPCOUNT += 1))
>> service nfs restart
>> /usr/sbin/rpc.idmapd
>> mount -t nfs4 127.0.0.1:/ /mnt|| return 1;
>> ls -l /var/lib/nfs/rpc_pipefs/nfs/*/
>> umount /mnt
>> echo $LOOPCOUNT
>> done
>>
>> ===============================================================================
>> Code: af 60 01 00 00 89 fa 89 f0 e8 64 cf 89 f0 e8 5c 7c 64 cf 31 c0 8b 5c 24 10 8b
>> 74 24 14 8b 7c 24 18 8b 6c 24 1c 83 c4 20 c3 <0f> 0b eb fc 8b 46 28 c7 44 24 08 20
>> de ee f0 c7 44 24 04 56 ea
>> EIP:[<f0ee92ea>] __rpc_create_common+0x8a/0xc0 [sunrpc] SS:ESP 0068:eccb5d28
>> ---[ end trace 8f5606cd08928ed2]---
>> Kernel panic - not syncing: Fatal exception
>> Pid:7131, comm: mount.nfs4 Tainted: G D -------------------2.6.32 #1
>> Call Trace:
>> [<c080ad18>] ? panic+0x42/0xed
>> [<c080e42c>] ? oops_end+0xbc/0xd0
>> [<c040b090>] ? do_invalid_op+0x0/0x90
>> [<c040b10f>] ? do_invalid_op+0x7f/0x90
>> [<f0ee92ea>] ? __rpc_create_common+0x8a/0xc0[sunrpc]
>> [<f0edc433>] ? rpc_free_task+0x33/0x70[sunrpc]
>> [<f0ed6508>] ? prc_call_sync+0x48/0x60[sunrpc]
>> [<f0ed656e>] ? rpc_ping+0x4e/0x60[sunrpc]
>> [<f0ed6eaf>] ? rpc_create+0x38f/0x4f0[sunrpc]
>> [<c080d80b>] ? error_code+0x73/0x78
>> [<f0ee92ea>] ? __rpc_create_common+0x8a/0xc0[sunrpc]
>> [<c0532bda>] ? d_lookup+0x2a/0x40
>> [<f0ee94b1>] ? rpc_mkpipe+0x111/0x1b0[sunrpc]
>> [<f10a59f4>] ? nfs_create_rpc_client+0xb4/0xf0[nfs]
>> [<f10d6c6d>] ? nfs_fscache_get_client_cookie+0x1d/0x50[nfs]
>> [<f10d3fcb>] ? nfs_idmap_new+0x7b/0x140[nfs]
>> [<c05e76aa>] ? strlcpy+0x3a/0x60
>> [<f10a60ca>] ? nfs4_set_client+0xea/0x2b0[nfs]
>> [<f10a6d0c>] ? nfs4_create_server+0xac/0x1b0[nfs]
>> [<c04f1400>] ? krealloc+0x40/0x50
>> [<f10b0e8b>] ? nfs4_remote_get_sb+0x6b/0x250[nfs]
>> [<c04f14ec>] ? kstrdup+0x3c/0x60
>> [<c0520739>] ? vfs_kern_mount+0x69/0x170
>> [<f10b1a3c>] ? nfs_do_root_mount+0x6c/0xa0[nfs]
>> [<f10b1b47>] ? nfs4_try_mount+0x37/0xa0[nfs]
>> [<f10afe6d>] ? nfs4_validate_text_mount_data+-x7d/0xf0[nfs]
>> [<f10b1c42>] ? nfs4_get_sb+0x92/0x2f0
>> [<c0520739>] ? vfs_kern_mount+0x69/0x170
>> [<c05366d2>] ? get_fs_type+0x32/0xb0
>> [<c052089f>] ? do_kern_mount+0x3f/0xe0
>> [<c053954f>] ? do_mount+0x2ef/0x740
>> [<c0537740>] ? copy_mount_options+0xb0/0x120
>> [<c0539a0e>] ? sys_mount+0x6e/0xa0
>
> Hi,
>
> Does the following patch fix the problem?

Thanks Trond.

After this patch, NFS client runs correctly.

>
> Cheers
> Trond
>
> --------------------------
> SUNRPC: Fix a BUG in __rpc_create_common
>
> From: Trond Myklebust <[email protected]>
>
> Mi Jinlong reports:
>
>
> When testing NFSv4 at RHEL6 with kernel 2.6.32, I got a kernel panic
> at NFS client's __rpc_create_common function.
>
> The panic place is:
> rpc_mkpipe
> __rpc_lookup_create() <=== find pipefile *idmap*
> __rpc_mkpipe() <=== pipefile is *idmap*
> __rpc_create_common()
> ****** BUG_ON(!d_unhashed(dentry)); ****** *panic*
>
> The test is wrong: we can find ourselves with a hashed negative dentry here
> if the idmapper tried to look up the file before we got round to creating
> it.
>
> Just replace the BUG_ON() with a d_drop(dentry).
>
> Reported-by: Mi Jinlong <[email protected]>
> Signed-off-by: Trond Myklebust <[email protected]>
> ---
>
> net/sunrpc/rpc_pipe.c | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>
>
> diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
> index 10a17a3..5356d95 100644
> --- a/net/sunrpc/rpc_pipe.c
> +++ b/net/sunrpc/rpc_pipe.c
> @@ -466,7 +466,7 @@ static int __rpc_create_common(struct inode *dir, struct dentry *dentry,
> {
> struct inode *inode;
>
> - BUG_ON(!d_unhashed(dentry));
> + d_drop(dentry);
> inode = rpc_get_inode(dir->i_sb, mode);
> if (!inode)
> goto out_err;
>
>

--
----
thanks
Mi Jinlong


2010-12-20 09:56:11

by Mi Jinlong

[permalink] [raw]
Subject: Re: kernel panic when mount NFSv4

hello,

At the latest kernel(2.6.37-rc6), I got warning message as below:

------------[ cut here ]------------
kernel BUG at net/sunrpc/rpc_pipe.c:469!
invalid opcode: 0000 [#1] SMP
last sysfs file: /sys/module/nfsd/initstate
Modules linked in: nfs fscache nfsd lockd nfs_acl auth_rpcgss sunrpc exportfs ipv6 ext3 jbd dm_mirror dm_region_hash dm_log dm_mod sg ppdev 8139too 8139cp r8169 mii parport_pc parport pcspkr serio_raw i2c_i801 iTCO_wdt iTCO_vendor_support snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer snd soundcore snd_page_alloc ext4 mbcache jbd2 sd_mod crc_t10dif pata_acpi ata_generic ata_piix usb_storage nouveau ttm drm_kms_helper drm i2c_algo_bit i2c_core video output [last unloaded: scsi_wait_scan]

Pid: 7371, comm: mount.nfs4 Not tainted 2.6.37-rc6+ #2 E945GCZ/ASPIRE AG1720
EIP: 0060:[<fed81f6a>] EFLAGS: 00010246 CPU: 0
EIP is at __rpc_create_common+0x8a/0xc0 [sunrpc]
EAX: f64b4300 EBX: f0c3eb64 ECX: 00001180 EDX: f0c3eb64
ESI: f64b4300 EDI: 00001180 EBP: f09e0000 ESP: f12efd20
DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
Process mount.nfs4 (pid: 7371, ti=f12ee000 task=f0964530 task.ti=f12ee000)
Stack:
f8456d84 c0520e1a f0c5f21c f12efd6c f0c3eb64 f64b4380 00001180 f8456d84
fed82121 fed86a60 f09e0000 f48026d0 00000010 00000000 000000d0 f0c5f21c
f8456d84 f64b4300 f09e0000 11bcc18d 00000005 f8456d84 f09e0000 f28b7400
Call Trace:
[<c0520e1a>] ? d_lookup+0x2a/0x40
[<fed82121>] ? rpc_mkpipe+0x111/0x1b0 [sunrpc]
[<f844ddeb>] ? nfs_idmap_new+0x7b/0x140 [nfs]
[<c05c42da>] ? strlcpy+0x3a/0x60
[<f841fc3a>] ? nfs4_set_client+0xea/0x2b0 [nfs]
[<f841fec1>] ? nfs4_create_server+0xc1/0x2d0 [nfs]
[<f842afd9>] ? nfs4_remote_mount+0x59/0x2c0 [nfs]
[<c0510f1d>] ? vfs_kern_mount+0x7d/0x230
[<f842af80>] ? nfs4_remote_mount+0x0/0x2c0 [nfs]
[<f842ab2c>] ? nfs_do_root_mount+0x6c/0xa0 [nfs]
[<f842ac37>] ? nfs4_try_mount+0x37/0xa0 [nfs]
[<f84291ad>] ? nfs4_validate_text_mount_data+0x7d/0xf0 [nfs]
[<f842bf22>] ? nfs4_get_sb+0x92/0x2f0 [nfs]
[<c051102c>] ? vfs_kern_mount+0x18c/0x230
[<c0524762>] ? get_fs_type+0x32/0xb0
[<c051112f>] ? do_kern_mount+0x3f/0xe0
[<c0527356>] ? do_mount+0x306/0x6f0
[<c0525640>] ? copy_mount_options+0xb0/0x120
[<c05277ae>] ? sys_mount+0x6e/0xa0
[<c040a59f>] ? sysenter_do_call+0x12/0x28
Code: af 50 01 00 00 89 fa 89 d8 e8 13 e3 79 c1 89 d8 e8 cc d5 79 c1 31 c0 8b 5c 24 10 8b 74 24 14 8b 7c 24 18 8b 6c 24 1c 83 c4 20 c3 <0f> 0b eb fe 8b 43 28 c7 44 24 08 00 6a d8 fe c7 44 24 04 8f 75
EIP: [<fed81f6a>] __rpc_create_common+0x8a/0xc0 [sunrpc] SS:ESP 0068:f12efd20
---[ end trace 49fbc098c75066aa ]---



2010-12-20 21:19:44

by Myklebust, Trond

[permalink] [raw]
Subject: Re: kernel panic when mount NFSv4

On Tue, 2010-12-14 at 16:58 +0800, Mi Jinlong wrote:
> Hi,
>
> When testing NFSv4 at RHEL6 with kernel 2.6.32, I got a kernel panic
> at NFS client's __rpc_create_common function.
>
> The panic place is:
> rpc_mkpipe
> __rpc_lookup_create() <=== find pipefile *idmap*
> __rpc_mkpipe() <=== pipefile is *idmap*
> __rpc_create_common()
> ****** BUG_ON(!d_unhashed(dentry)); ****** *panic*
>
> It means that the dentry's d_flags have be set DCACHE_UNHASHED,
> but it should not be set here.
>
> Is someone known this bug? or give me some idea?
>
> A reproduce program is append, but it can't reproduce the bug every time.
> the export is: "/nfsroot *(rw,no_root_squash,fsid=0,insecure)"
>
> And the panic message is append.
>
> ============================================================================
> #!/bin/sh
>
> LOOPTOTAL=768
> LOOPCOUNT=0
> ret=0
>
> while [ $LOOPCOUNT -ne $LOOPTOTAL ]
> do
> ((LOOPCOUNT += 1))
> service nfs restart
> /usr/sbin/rpc.idmapd
> mount -t nfs4 127.0.0.1:/ /mnt|| return 1;
> ls -l /var/lib/nfs/rpc_pipefs/nfs/*/
> umount /mnt
> echo $LOOPCOUNT
> done
>
> ===============================================================================
> Code: af 60 01 00 00 89 fa 89 f0 e8 64 cf 89 f0 e8 5c 7c 64 cf 31 c0 8b 5c 24 10 8b
> 74 24 14 8b 7c 24 18 8b 6c 24 1c 83 c4 20 c3 <0f> 0b eb fc 8b 46 28 c7 44 24 08 20
> de ee f0 c7 44 24 04 56 ea
> EIP:[<f0ee92ea>] __rpc_create_common+0x8a/0xc0 [sunrpc] SS:ESP 0068:eccb5d28
> ---[ end trace 8f5606cd08928ed2]---
> Kernel panic - not syncing: Fatal exception
> Pid:7131, comm: mount.nfs4 Tainted: G D -------------------2.6.32 #1
> Call Trace:
> [<c080ad18>] ? panic+0x42/0xed
> [<c080e42c>] ? oops_end+0xbc/0xd0
> [<c040b090>] ? do_invalid_op+0x0/0x90
> [<c040b10f>] ? do_invalid_op+0x7f/0x90
> [<f0ee92ea>] ? __rpc_create_common+0x8a/0xc0[sunrpc]
> [<f0edc433>] ? rpc_free_task+0x33/0x70[sunrpc]
> [<f0ed6508>] ? prc_call_sync+0x48/0x60[sunrpc]
> [<f0ed656e>] ? rpc_ping+0x4e/0x60[sunrpc]
> [<f0ed6eaf>] ? rpc_create+0x38f/0x4f0[sunrpc]
> [<c080d80b>] ? error_code+0x73/0x78
> [<f0ee92ea>] ? __rpc_create_common+0x8a/0xc0[sunrpc]
> [<c0532bda>] ? d_lookup+0x2a/0x40
> [<f0ee94b1>] ? rpc_mkpipe+0x111/0x1b0[sunrpc]
> [<f10a59f4>] ? nfs_create_rpc_client+0xb4/0xf0[nfs]
> [<f10d6c6d>] ? nfs_fscache_get_client_cookie+0x1d/0x50[nfs]
> [<f10d3fcb>] ? nfs_idmap_new+0x7b/0x140[nfs]
> [<c05e76aa>] ? strlcpy+0x3a/0x60
> [<f10a60ca>] ? nfs4_set_client+0xea/0x2b0[nfs]
> [<f10a6d0c>] ? nfs4_create_server+0xac/0x1b0[nfs]
> [<c04f1400>] ? krealloc+0x40/0x50
> [<f10b0e8b>] ? nfs4_remote_get_sb+0x6b/0x250[nfs]
> [<c04f14ec>] ? kstrdup+0x3c/0x60
> [<c0520739>] ? vfs_kern_mount+0x69/0x170
> [<f10b1a3c>] ? nfs_do_root_mount+0x6c/0xa0[nfs]
> [<f10b1b47>] ? nfs4_try_mount+0x37/0xa0[nfs]
> [<f10afe6d>] ? nfs4_validate_text_mount_data+-x7d/0xf0[nfs]
> [<f10b1c42>] ? nfs4_get_sb+0x92/0x2f0
> [<c0520739>] ? vfs_kern_mount+0x69/0x170
> [<c05366d2>] ? get_fs_type+0x32/0xb0
> [<c052089f>] ? do_kern_mount+0x3f/0xe0
> [<c053954f>] ? do_mount+0x2ef/0x740
> [<c0537740>] ? copy_mount_options+0xb0/0x120
> [<c0539a0e>] ? sys_mount+0x6e/0xa0

Hi,

Does the following patch fix the problem?

Cheers
Trond

--------------------------
SUNRPC: Fix a BUG in __rpc_create_common

From: Trond Myklebust <[email protected]>

Mi Jinlong reports:


When testing NFSv4 at RHEL6 with kernel 2.6.32, I got a kernel panic
at NFS client's __rpc_create_common function.

The panic place is:
rpc_mkpipe
__rpc_lookup_create() <=== find pipefile *idmap*
__rpc_mkpipe() <=== pipefile is *idmap*
__rpc_create_common()
****** BUG_ON(!d_unhashed(dentry)); ****** *panic*

The test is wrong: we can find ourselves with a hashed negative dentry here
if the idmapper tried to look up the file before we got round to creating
it.

Just replace the BUG_ON() with a d_drop(dentry).

Reported-by: Mi Jinlong <[email protected]>
Signed-off-by: Trond Myklebust <[email protected]>
---

net/sunrpc/rpc_pipe.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)


diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
index 10a17a3..5356d95 100644
--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -466,7 +466,7 @@ static int __rpc_create_common(struct inode *dir, struct dentry *dentry,
{
struct inode *inode;

- BUG_ON(!d_unhashed(dentry));
+ d_drop(dentry);
inode = rpc_get_inode(dir->i_sb, mode);
if (!inode)
goto out_err;


--
Trond Myklebust
Linux NFS client maintainer

NetApp
[email protected]
http://www.netapp.com


2012-12-14 07:20:44

by Willy Tarreau

[permalink] [raw]
Subject: Re: [2.6.32.y, 2.6.34.y] Re: kernel panic when mount NFSv4

Hi Jonathan,

On Thu, Dec 13, 2012 at 09:39:58PM -0800, Jonathan Nieder wrote:
> Hi Willy et al,
>
> Please consider
>
> beb0f0a9fba1 kernel panic when mount NFSv4, 2010-12-20
>
> for application to kernel.org's 2.6.32.y and 2.6.34.y trees. The
> patch was applied upstream during the 2.6.38 merge window, so newer
> kernels don't need it.
>
> (Context: <http://bugs.debian.org/695872>.) Tom Downes (cc-ed)
> experienced the bug on a Debian kernel close to 2.6.32.58 and
> confirmed that the patch doesn't seem to hurt.
>
> The patch is part of Fedora 13's 2.6.34-based and Fedora 14's
> 2.6.35-based kernels[1]. It was also included in the RHEL kernel at
> some point between 2.6.32-71.29.1.el6 and 2.6.32-131.0.15.el6[2].
>
> Thoughts of all kinds welcome, as always.

Thank you for all the details, as always :-)

I'm queuing this patch for 2.6.32.61.

Best regards,
Willy


2012-12-14 05:40:07

by Jonathan Nieder

[permalink] [raw]
Subject: [2.6.32.y, 2.6.34.y] Re: kernel panic when mount NFSv4

Hi Willy et al,

Please consider

beb0f0a9fba1 kernel panic when mount NFSv4, 2010-12-20

for application to kernel.org's 2.6.32.y and 2.6.34.y trees. The
patch was applied upstream during the 2.6.38 merge window, so newer
kernels don't need it.

(Context: <http://bugs.debian.org/695872>.) Tom Downes (cc-ed)
experienced the bug on a Debian kernel close to 2.6.32.58 and
confirmed that the patch doesn't seem to hurt.

The patch is part of Fedora 13's 2.6.34-based and Fedora 14's
2.6.35-based kernels[1]. It was also included in the RHEL kernel at
some point between 2.6.32-71.29.1.el6 and 2.6.32-131.0.15.el6[2].

Thoughts of all kinds welcome, as always.

Regards,
Jonathan

[1] https://bugzilla.redhat.com/673207
[2] https://oss.oracle.com/git/?p=redpatch.git;a=commit;h=8028cccdc4b1