unknown partition table starting with 2.6.28

unknown partition table starting with 2.6.28

[Timothy D. Lenz]

I am trying to update my kernel from 2.6.26.8 to the current .32. 
Starting at .27 I get an acpi conflict:

ACPI: Power Button (CM) [PWRB]
i2c-adapter i2c-0: nForce2 SMBus adapter at 0x1c00
ACPI: I/O resource nForce2_smbus [0x1c40-0x1c7f] conflicts with ACPI 
region SM01 [0x1c40-0x1c45]
ACPI: Device needs an ACPI driver
i2c-adapter i2c-1: nForce2 SMBus adapter at 0x1c40
ACPI: Expecting a [Reference] package element, found type 0
thermal LNXTHERM:01: registered as thermal_zone0

Starting with .28 I am getting an error about unknown partition table 
for all 3 md's. md0 is boot and main programs, md1 is swap, md2 is 
mostly recordings storage for vdr. All 3 are raid 1 and raid is built in.

dmesg for .28 boot: http://pastebin.com/m1a459731
dmesg for .29 boot: http://pastebin.com/m419d7207


I tried to go directly to .32.2 but it didn't even mount md2. But that 
might have been an error by me. So was stepping through kernels to see 
where/if it stopped mounting.

The acpi error was known and seemed to effect all nforce chipset boards. 
I'm hoping that one is fixed.

Re: unknown partition table starting with 2.6.28

[John Robinson]

On 15/01/2010 23:58, Timothy D. Lenz wrote:
> I am trying to update my kernel from 2.6.26.8 to the current .32. 
[...]
> Starting with .28 I am getting an error about unknown partition table 
> for all 3 md's. md0 is boot and main programs, md1 is swap, md2 is 
> mostly recordings storage for vdr. All 3 are raid 1 and raid is built in.

Your md devices aren't partitioned so you can quite safely ignore the 
warning. See also http://marc.info/?l=linux-raid&m=125797242110594&w=2

Cheers,

John.

Re: unknown partition table starting with 2.6.28

[Bill Davidsen]

John Robinson wrote:
> On 15/01/2010 23:58, Timothy D. Lenz wrote:
>> I am trying to update my kernel from 2.6.26.8 to the current .32. 
> [...]
>> Starting with .28 I am getting an error about unknown partition table 
>> for all 3 md's. md0 is boot and main programs, md1 is swap, md2 is 
>> mostly recordings storage for vdr. All 3 are raid 1 and raid is built 
>> in.
>
> Your md devices aren't partitioned so you can quite safely ignore the 
> warning. See also http://marc.info/?l=linux-raid&m=125797242110594&w=2

To clarify that a bit, the kernel can use several partition formats, and 
something in the partitions looks like a partition table but not a 
*valid* partition table. So the kernel warns that it doesn't recognize 
the table.

I suspect that using a different superblock type would change (probably 
eliminate) this, putting the md information at the start of the 
partition, of in a bit or whatever makes the kernel happy. The kernel 
would make us happy if it checked for a valid md superblock at the *end* 
of the partition, but there may be reasons why that's undesirable.

Finally, I'm less willing than John to say you can ignore it, any time 
something comes close enough to working (in an undesired way) to 
generate an error message, if there's a simple way to be sure the kernel 
doesn't try to use random data as a partition table, you might well want 
to take a step to prevent a problem now.

I believe it arises out of all arrays being partitionable recently, 
again the details don't come to mid, I've been pretty head down on 
another project since November.

-- 
Bill Davidsen <davidsen@tmr.com>
  "We can't solve today's problems by using the same thinking we
   used in creating them." - Einstein

Re: unknown partition table starting with 2.6.28

[John Robinson]

On 01/02/2010 20:46, Bill Davidsen wrote:
> John Robinson wrote:
>> On 15/01/2010 23:58, Timothy D. Lenz wrote:
>>> I am trying to update my kernel from 2.6.26.8 to the current .32. 
>> [...]
>>> Starting with .28 I am getting an error about unknown partition table 
>>> for all 3 md's. md0 is boot and main programs, md1 is swap, md2 is 
>>> mostly recordings storage for vdr. All 3 are raid 1 and raid is built 
>>> in.
>>
>> Your md devices aren't partitioned so you can quite safely ignore the 
>> warning. See also http://marc.info/?l=linux-raid&m=125797242110594&w=2
> 
> To clarify that a bit, the kernel can use several partition formats, and 
> something in the partitions looks like a partition table but not a 
> *valid* partition table. So the kernel warns that it doesn't recognize 
> the table.
> 
> I suspect that using a different superblock type would change (probably 
> eliminate) this, putting the md information at the start of the 
> partition, of in a bit or whatever makes the kernel happy. The kernel 
> would make us happy if it checked for a valid md superblock at the *end* 
> of the partition, but there may be reasons why that's undesirable.
> 
> Finally, I'm less willing than John to say you can ignore it, any time 
> something comes close enough to working (in an undesired way) to 
> generate an error message, if there's a simple way to be sure the kernel 
> doesn't try to use random data as a partition table, you might well want 
> to take a step to prevent a problem now.
> 
> I believe it arises out of all arrays being partitionable recently, 
> again the details don't come to mid, I've been pretty head down on 
> another project since November.

I don't think this analysis is correct. Yes, the situation has arisen 
out of all arrays - in fact all block devices - being partitionable, but 
the warning's not because of something that looks like a dodgy partition 
table, it is precisely what it says, a statement that the device does 
not contain a valid partition table. I am essentially repeating the 
contents of Doug Ledford's earlier post to this list, to which I 
referred above.

Cheers,

John.

Re: unknown partition table starting with 2.6.28

[Bill Davidsen]

John Robinson wrote:
> On 01/02/2010 20:46, Bill Davidsen wrote:
>> John Robinson wrote:
>>> On 15/01/2010 23:58, Timothy D. Lenz wrote:
>>>> I am trying to update my kernel from 2.6.26.8 to the current .32. 
>>> [...]
>>>> Starting with .28 I am getting an error about unknown partition 
>>>> table for all 3 md's. md0 is boot and main programs, md1 is swap, 
>>>> md2 is mostly recordings storage for vdr. All 3 are raid 1 and raid 
>>>> is built in.
>>>
>>> Your md devices aren't partitioned so you can quite safely ignore 
>>> the warning. See also 
>>> http://marc.info/?l=linux-raid&m=125797242110594&w=2
>>
>> To clarify that a bit, the kernel can use several partition formats, 
>> and something in the partitions looks like a partition table but not 
>> a *valid* partition table. So the kernel warns that it doesn't 
>> recognize the table.
>>
>> I suspect that using a different superblock type would change 
>> (probably eliminate) this, putting the md information at the start of 
>> the partition, of in a bit or whatever makes the kernel happy. The 
>> kernel would make us happy if it checked for a valid md superblock at 
>> the *end* of the partition, but there may be reasons why that's 
>> undesirable.
>>
>> Finally, I'm less willing than John to say you can ignore it, any 
>> time something comes close enough to working (in an undesired way) to 
>> generate an error message, if there's a simple way to be sure the 
>> kernel doesn't try to use random data as a partition table, you might 
>> well want to take a step to prevent a problem now.
>>
>> I believe it arises out of all arrays being partitionable recently, 
>> again the details don't come to mid, I've been pretty head down on 
>> another project since November.
>
> I don't think this analysis is correct. Yes, the situation has arisen 
> out of all arrays - in fact all block devices - being partitionable, 
> but the warning's not because of something that looks like a dodgy 
> partition table, it is precisely what it says, a statement that the 
> device does not contain a valid partition table. I am essentially 
> repeating the contents of Doug Ledford's earlier post to this list, to 
> which I referred above.

But the question is, *should* it contain a valid partition table, or 
even anything which looks enough like a partition table to have the 
kernel look at it hard enough to think it's invalid? I have several 
devices on one system which contain essentially random data, and I don't 
see this, so I assume that my data never looks enough like a partition 
table to trigger this. At least to 2.6.33-rc6, which I did boot.

-- 
Bill Davidsen <davidsen@tmr.com>
  "We can't solve today's problems by using the same thinking we
   used in creating them." - Einstein

Re: unknown partition table starting with 2.6.28

[Bill Davidsen]

Bill Davidsen wrote:
> John Robinson wrote:
>> On 01/02/2010 20:46, Bill Davidsen wrote:
>>> John Robinson wrote:
>>>> On 15/01/2010 23:58, Timothy D. Lenz wrote:
>>>>> I am trying to update my kernel from 2.6.26.8 to the current .32. 
>>>> [...]
>>>>> Starting with .28 I am getting an error about unknown partition 
>>>>> table for all 3 md's. md0 is boot and main programs, md1 is swap, 
>>>>> md2 is mostly recordings storage for vdr. All 3 are raid 1 and 
>>>>> raid is built in.
>>>>
>>>> Your md devices aren't partitioned so you can quite safely ignore 
>>>> the warning. See also 
>>>> http://marc.info/?l=linux-raid&m=125797242110594&w=2
>>>
>>> To clarify that a bit, the kernel can use several partition formats, 
>>> and something in the partitions looks like a partition table but not 
>>> a *valid* partition table. So the kernel warns that it doesn't 
>>> recognize the table.
>>>
>>> I suspect that using a different superblock type would change 
>>> (probably eliminate) this, putting the md information at the start 
>>> of the partition, of in a bit or whatever makes the kernel happy. 
>>> The kernel would make us happy if it checked for a valid md 
>>> superblock at the *end* of the partition, but there may be reasons 
>>> why that's undesirable.
>>>
>>> Finally, I'm less willing than John to say you can ignore it, any 
>>> time something comes close enough to working (in an undesired way) 
>>> to generate an error message, if there's a simple way to be sure the 
>>> kernel doesn't try to use random data as a partition table, you 
>>> might well want to take a step to prevent a problem now.
>>>
>>> I believe it arises out of all arrays being partitionable recently, 
>>> again the details don't come to mid, I've been pretty head down on 
>>> another project since November.
>>
>> I don't think this analysis is correct. Yes, the situation has arisen 
>> out of all arrays - in fact all block devices - being partitionable, 
>> but the warning's not because of something that looks like a dodgy 
>> partition table, it is precisely what it says, a statement that the 
>> device does not contain a valid partition table. I am essentially 
>> repeating the contents of Doug Ledford's earlier post to this list, 
>> to which I referred above.
>
> But the question is, *should* it contain a valid partition table, or 
> even anything which looks enough like a partition table to have the 
> kernel look at it hard enough to think it's invalid? I have several 
> devices on one system which contain essentially random data, and I 
> don't see this, so I assume that my data never looks enough like a 
> partition table to trigger this. At least to 2.6.33-rc6, which I did 
> boot.
>
On reflection I may not have said this clearly. I have block devices 
which do not have partition tables and which do not trigger this 
message. Therefore something is triggering this message, beyond the lack 
of a partition table. My thought is that it may be some logic called 
when the array is assembled, and some data on the array.

-- 
Bill Davidsen <davidsen@tmr.com>
  "We can't solve today's problems by using the same thinking we
   used in creating them." - Einstein