[U-Boot] Possible race condition when accessing SPI NOR Flash ?

[Valentin Longchamp]

Hello Wolfgang,

On 05/02/2014 12:31 AM, Wolfgang Denk wrote:
> Dear Valentin,
> 
> In message <53623597.8040909 at keymile.com> you wrote:
>>
>> Now when fw_setenv ([1], [2]) updates the environment variables, it sometimes
>> (approximately 1 out of 100 runs) triggers such kernel errors:
> ...
>> I see the same behavior with both the 2013.10 and the 2014.04 releases of
>> u-boot/fw_env. The kernel we are using is 3.10.36.
>>
>> I suspect that the problem is related to SPI NOR/m25p80 driver: on the system we
>> have a NAND Flash device with UBI volumes. If I create 2 ubi volumes on the NAND
>> Flash and configure fw_setenv (/etc/fw_env.config) to use them instead of the
>> the mtd devices targetting the s25fl256s1, I am not able to reproduce the
>> problem, even over more than 10'000 runs.
> 
> Um... this is _Linux_ crashing - at this point the U-Boot driver has
> nothing to do with it..  If there is a problem, then with the Linux
> kernel / driver code.  I guess you should rather post this on the MTD
> mailing ist.
> 

Yes, it was clear for me that this is Linux crashing, as I write "it [..]
triggers [..] kernel errors." I have posted it to the linux-mtd ML, I have just
added the u-boot ML as CC since fw_env is u-boot code and it triggers it, so I
though it could be of interest.

Best regards,

Valentin