UBIFS errors when file-system is full

[Richard Weinberger]

Am 14.07.2015 um 12:08 schrieb Bhuvanchandra DV:
> On 07/14/2015 02:12 PM, Richard Weinberger wrote:
> 
>> Am 14.07.2015 um 10:29 schrieb Bhuvanchandra DV:
>>> On 07/14/2015 12:02 PM, Richard Weinberger wrote:
>>>
>>>> Am 14.07.2015 um 08:30 schrieb Bhuvanchandra DV:
>>>>> Reproduced the issue with a clean UBI image.
>>>> On 4.1?
>>>> How can you reproduce?
>>> Flashed a clean UBI image with 4.1.
>>> I can reproduce it by amost filling up the flash and doing a power resets for around ~200 cycles.
>> And it really happens only if you're filling up the UBIFS?
> 
> The only thing observed so far during this tests is when the journactl log starts filling up the flash
> memory and at some point of time fails to mount the ubifs.

You mean filling up the filesystem? How and when does the power cut happen?

> Flashed an Image which occupies less flash ~40-50%. Run the same tests for around 1200 power cycles
> no issues observed during mounting but still there are few error messages:
> ..
> [    6.879643] ubi0 error: __wl_get_peb: no free eraseblocks

This message cannot come from a recent kernel.

> So came to an assumption that filling the flash to max lead to this issue.
> 
> Could there be any other possibility for this issue apart from filling up the flash ?
> 
>> If you set the UBI module parameter "fm_debug", does the EBA selfcheck trigger?
> 
> Yes, EBA selfcheck got triggered. Atleast i could see the debug printks added
> in 'self_check_eba' method after setting the fm_debug parameter.
> 
>>
>>> During some point U-Boot cannot mount the ubifs partition and fails with:
>>> "Error reading superblock on volume 'ubi0:rootfs' errno=-22!"
>> How exactly is U-Boot involved? Does U-Boot touch UBI in any way?
> 
> kernel, device tree blobs are available in rootfs /boot. U-Boot mounts the ubi partition
> and loads the kernel and device tree blob.
> 
> Also U-Boot is involved during flashing the UBI image to flash.

In you last mail you wrote
"During some point U-Boot cannot mount the ubifs partition and fails with"..

So, please reproduce from scratch(!) with a recent kernel (4.1 or newer) and provide all needed infos.
Otherwise I see no way howto help you.

Thanks,
//richard