linux-kernel - Re: cifs: ls of mount point gives input/output error (probably related to CIFS: getdents() broken for large dirs)

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Date:	Fri, 30 Dec 2011 23:46:24 +0200
From:	Konstantinos Skarlatos <k.skarlatos@...il.com>
To:	Jeff Layton <jlayton@...hat.com>
CC:	linux-kernel@...r.kernel.org, linux-cifs@...r.kernel.org
Subject: Re: cifs: ls of mount point gives input/output error (probably related
 to CIFS: getdents() broken for large dirs)

On 30/12/2011 8:00 μμ, Konstantinos Skarlatos wrote:
> On 30/12/2011 3:11 μμ, Jeff Layton wrote:
>> On Fri, 30 Dec 2011 11:04:59 +0200
>> Konstantinos Skarlatos<k.skarlatos@...il.com>  wrote:
>>
>>> On 29/12/2011 3:54 μμ, Konstantinos Skarlatos wrote:
>>>> On Πέμπτη, 29 Δεκέμβριος 2011 3:39:30 μμ, Jeff Layton wrote:
>>>>> On Thu, 29 Dec 2011 12:30:18 +0200
>>>>> Konstantinos Skarlatos<k.skarlatos@...il.com>   wrote:
>>>>>
>>>>>> On 29/12/2011 4:04 πμ, Jeff Layton wrote:
>>>>>>> On Thu, 29 Dec 2011 02:08:57 +0200
>>>>>>> Konstantinos Skarlatos<k.skarlatos@...il.com>    wrote:
>>>>>>>
>>>>>>>> I mount via cifs a windows XP share, df gives me correct sizes,
>>>>>>>> but when
>>>>>>>> I ls the mount point i get input/output error.
>>>>>>>> strace: http://pastebin.com/WXf8M1nu
>>>>>>>>
>>>>>>>> mount --verbose -t cifs -o 
>>>>>>>> username=administrator,password=blahblah
>>>>>>>> //192.168.0.11/jobs /mnt/backups/montaz/jobs
>>>>>>>> mount.cifs kernel mount options:
>>>>>>>> ip=192.168.0.11,unc=\\192.168.0.11\jobs,,ver=1,user=administrator,pass=******** 
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> df
>>>>>>>> //192.168.0.11/jobs                                       114464
>>>>>>>> 105196      9268  92% /mnt/backups/montaz/jobs
>>>>>>>>
>>>>>>>> ls /mnt/backups/montaz/jobs/
>>>>>>>> ls: reading directory /mnt/backups/montaz/jobs/: Input/output 
>>>>>>>> error
>>>>>>>> total 0
>>>>>>>>
>>>>>>>> the fun thing is that i can cd to a lower level directory, and ls
>>>>>>>> works
>>>>>>>> fine there! only the mount point has the problem
>>>>>>>>
>>>>>>>> ls /mnt/backups/montaz/jobs/test
>>>>>>>> total 44K
>>>>>>>> drwxr-xr-x 1 root root    0 Apr 30  2010 blah blah/
>>>>>>>> ......
>>>>>>>>
>>>>>>>> kernel version 3.2rc7
>>>>>>>>
>>>>>>>> this seems to be related to :
>>>>>>>> https://lkml.org/lkml/2011/8/1/427
>>>>>>>> Re: [3.0.0+][Regression][Bisected] CIFS: getdents() broken for
>>>>>>>> large dirs
>>>>>>>>
>>>>>>> Hmmm, maybe. What makes you think that it's related? What sort of
>>>>>>> server are you seeing this against?
>>>>>> Windows XP service pack 2 (greek)
>>>>>
>>>>> How many files are in the directory?
>>>>>
>>>> 140 folders and 20 files
>>>>
>>> Attached is a tcp dump of my session.
>> I tried reproducing this here, but wasn't able to. Testing against my
>> xp box worked fine.
>>
>> Most likely, the FIND_FILE responses are falling afoul of the code in
>> coalesce_t2 or check2ndT2. Unfortunately that code is pretty
>> complicated and I'm not certain what the problem actually is...
>>
>> One thing that's interesting is that the total data being sent in the
>> request is rather large (16336 bytes). I think that's legit, but maybe
>> it's exceeding the end of the buffer once we try to coalesce it.
>>
>> Would it be possible to get the cFYI output from this test?
> I did not get a cFYI output from that test, but i redid a 
> mount-ls-umount and am attaching the tcpdump
> Also here http://pastebin.com/J20uC6kU you can find the cifsFYI and 
> the contents of /proc/fs/cifs/DebugData form the same test
>>
>> Is this a regression? Did it work with earlier kernels and only
>> recently start failing?
>>
> I do not know, and i am a bit afraid to downgrade this machine below 
> 3.0 due to some changes arch linux has introduced recently. I can 
> always set up a few virtual machines though, and i can even request 
> permission from my company to give you shell access if you like. Which 
> kernel versions would you like me to test?
I just tested  3.1.5-1-ARCH on a virtual machine and it works, so it is 
probably a regression... On the same virtual machine 3.2-rc7 produces 
input/output error. The virtual machine is a fresh install of arch linux.
here is the relevant pastebin http://pastebin.com/BwX2DqJC
and attached is the tcpdump
As a am a noob to all this, what should I do next in order to help you? 
maybe compile a 3.1 kernel from official sources to make sure no patches 
from arch linux interfere?


Download attachment "cifs-traffic.pcap" of type "application/octet-stream" (28885 bytes)