Re: [PATCH net] i40e: fix: remove needless retries of NVM update

[Jacob Keller <jacob.e.keller@intel.com>]

On 7/10/2024 3:44 PM, Tony Nguyen wrote:
> From: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
> 
> Remove wrong EIO to EGAIN conversion and pass all errors as is.
> 
> After commit 230f3d53a547 ("i40e: remove i40e_status"), which should only
> replace F/W specific error codes with Linux kernel generic, all EIO errors
> suddenly started to be converted into EAGAIN which leads nvmupdate to retry
> until it timeouts and sometimes fails after more than 20 minutes in the
> middle of NVM update, so NVM becomes corrupted.
> 
> The bug affects users only at the time when they try to update NVM, and
> only F/W versions that generate errors while nvmupdate. For example, X710DA2
> with 0x8000ECB7 F/W is affected, but there are probably more...
> 
> Command for reproduction is just NVM update:
>  ./nvmupdate64
> 
> In the log instead of:
>  i40e_nvmupd_exec_aq err I40E_ERR_ADMIN_QUEUE_ERROR aq_err I40E_AQ_RC_ENOMEM)
> appears:
>  i40e_nvmupd_exec_aq err -EIO aq_err I40E_AQ_RC_ENOMEM
>  i40e: eeprom check failed (-5), Tx/Rx traffic disabled
> 
> The problematic code did silently convert EIO into EAGAIN which forced
> nvmupdate to ignore EAGAIN error and retry the same operation until timeout.
> That's why NVM update takes 20+ minutes to finish with the fail in the end.
> 
> Fixes: 230f3d53a547 ("i40e: remove i40e_status")
> Co-developed-by: Kelvin Kang <kelvin.kang@intel.com>
> Signed-off-by: Kelvin Kang <kelvin.kang@intel.com>
> Reviewed-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
> Signed-off-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
> Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
> Tested-by: Tony Brelinski <tony.brelinski@intel.com>
> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
> ---
>  drivers/net/ethernet/intel/i40e/i40e_adminq.h | 4 ----
>  1 file changed, 4 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/i40e/i40e_adminq.h b/drivers/net/ethernet/intel/i40e/i40e_adminq.h
> index ee86d2c53079..55b5bb884d73 100644
> --- a/drivers/net/ethernet/intel/i40e/i40e_adminq.h
> +++ b/drivers/net/ethernet/intel/i40e/i40e_adminq.h
> @@ -109,10 +109,6 @@ static inline int i40e_aq_rc_to_posix(int aq_ret, int aq_rc)
>  		-EFBIG,      /* I40E_AQ_RC_EFBIG */
>  	};
>  
> -	/* aq_rc is invalid if AQ timed out */
> -	if (aq_ret == -EIO)
> -		return -EAGAIN;
> -

Makes sense. This hunk originated from commit bf848f328cf5 ("i40e: check
for AQ timeout in aq_rc decode") before the AQ return was converted to a
standard Linux error value. Previously we checked for
I40E_ERR_ADMIN_QUEUE_TIMEOUT, which is more specific. Now all errors
that were -EIO get converted, which could include a significantly higher
number of errors than just ADMIN_QUEUE_TIMEDOUT.

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>

>  	if (!((u32)aq_rc < (sizeof(aq_to_posix) / sizeof((aq_to_posix)[0]))))
>  		return -ERANGE;
>