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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Message-ID: <4EFE7080.5060302@gmail.com>
Date:	Sat, 31 Dec 2011 04:16:32 +0200
From:	Konstantinos Skarlatos <k.skarlatos@...il.com>
To:	Jeff Layton <jlayton@...hat.com>,
	Shirish Pargaonkar <shirishpargaonkar@...il.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 11:46 μμ, Konstantinos Skarlatos wrote:
> 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?
>
After some testing, vanilla 3.1.6 does not have this bug and 3.2.0-rc1 
has it.
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