Re: [PATCH] mmc: omap_hsmmc: Fix Oops in case of data errors

[Balaji T K <balajitk@ti.com>]

On Friday 09 November 2012 08:22 PM, Felipe Balbi wrote:
> On Fri, Nov 09, 2012 at 08:11:19PM +0530, Balaji T K wrote:
>> Setting end_cmd to 1 for Data Timeout/CRC leads to NULL pointer dereference of
>> host->cmd as the command complete has previously been handled.
>> Set end_cmd only in case of Data Timeout/CRC.
>
> this comment doesnt match code as code is setting end_cmd for cmd
> timeout and cmd crc, not data timeout/crc.

yes, you are right
s/Data/Cmd :-)

>
>> While at it restore error handling behaviour as was before the
>> "commit ae4bf788ee9bf7c2d51b0309117d1fcccbdd50a2
>> mmc: omap_hsmmc: consolidate error report handling of HSMMC IRQ"
>>
>> host->cmd->error should not be updated on data error case, only
>> host->data->error needs to be updated.
>> end_trans and end_crc should not to be set together, to avoid
>> mmc_request_done being called twice in case of Command CRC or command
>> Timeout.
>> Avoid soft reset of command internal state machine on data errors.
>
> looks to me you're doing to many changes in a single patch. Perhaps it
> deserves some splitting...
>

Let me check if I can split

>>
>> Signed-off-by: Balaji T K <balajitk@ti.com>
>> ---
>> based on mmc-fixes-for-3.7-rc5 in mmc_next
>>
>>   drivers/mmc/host/omap_hsmmc.c |   23 +++++++++++++++--------
>>   1 files changed, 15 insertions(+), 8 deletions(-)
>>
>> diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
>> index fedd258..6ea1da3 100644
>> --- a/drivers/mmc/host/omap_hsmmc.c
>> +++ b/drivers/mmc/host/omap_hsmmc.c
>> @@ -968,15 +968,20 @@ static inline void omap_hsmmc_reset_controller_fsm(struct omap_hsmmc_host *host,
>>   			__func__);
>>   }
>>
>> -static void hsmmc_command_incomplete(struct omap_hsmmc_host *host, int err)
>> +static void hsmmc_command_incomplete(struct omap_hsmmc_host *host,
>> +					int err, int end_cmd)
>>   {
>> -	omap_hsmmc_reset_controller_fsm(host, SRC);

This conditional reset can be separate patch if needed.

>> -	host->cmd->error = err;
>> +	if (end_cmd) {
>> +		omap_hsmmc_reset_controller_fsm(host, SRC);
>> +		if (host->cmd)
>> +			host->cmd->error = err;
>> +	}
>>
>>   	if (host->data) {
>>   		omap_hsmmc_reset_controller_fsm(host, SRD);
>>   		omap_hsmmc_dma_cleanup(host, err);
>> -	}
>> +	} else if (host->mrq && host->mrq->cmd)
>> +		host->mrq->cmd->error = err;

Updating the error code can also be split.
Let me know If you are Ok with this, I can send new series.

>>
>>   }
>>
>> @@ -990,14 +995,16 @@ static void omap_hsmmc_do_irq(struct omap_hsmmc_host *host, int status)
>>
>>   	if (status & ERR) {
>>   		omap_hsmmc_dbg_report_irq(host, status);
>> +
>> +		if (status & (CMD_TIMEOUT | CMD_CRC))
>> +			end_cmd = 1;
>>   		if (status & (CMD_TIMEOUT | DATA_TIMEOUT))
>> -			hsmmc_command_incomplete(host, -ETIMEDOUT);
>> +			hsmmc_command_incomplete(host, -ETIMEDOUT, end_cmd);
>>   		else if (status & (CMD_CRC | DATA_CRC))
>> -			hsmmc_command_incomplete(host, -EILSEQ);
>> +			hsmmc_command_incomplete(host, -EILSEQ, end_cmd);
>>
>> -		end_cmd = 1;
>>   		if (host->data || host->response_busy) {
>> -			end_trans = 1;
>> +			end_trans = !end_cmd;
>>   			host->response_busy = 0;
>>   		}
>>   	}
>> --
>> 1.7.5.4
>>
>> --
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>