[PATCH] mxcmmc: Internal error: Oops: 17 [#1] ARM from sg->offset

[Sascha Hauer]

On Wed, Jan 22, 2014 at 03:19:48PM +0800, Chris Ruehl wrote:
> On Wednesday, January 22, 2014 02:42 PM, Sascha Hauer wrote:
> >On Wed, Jan 22, 2014 at 12:32:39PM +0800, Chris Ruehl wrote:
> >>Function mxcmci_request() throw an exception on a imx27 cpu.
> >>This patch fix the problem by test the pointer before access it.
> >>
> >>diff --git a/drivers/mmc/host/mxcmmc.c b/drivers/mmc/host/mxcmmc.c
> >>index f7199c8..8645d6a 100644
> >>--- a/drivers/mmc/host/mxcmmc.c
> >>+++ b/drivers/mmc/host/mxcmmc.c
> >>@@ -347,7 +347,7 @@ static int mxcmci_setup_data(struct mxcmci_host *host, struct mmc_data *data)
> >>  		return 0;
> >>  	for_each_sg(data->sg, sg, data->sg_len, i) {
> >>-		if (sg->offset & 3 || sg->length & 3 || sg->length < 512) {
> >>+		if (sg && (sg->offset & 3 || sg->length & 3 || sg->length < 512)) {
> >The question is why sg is NULL. I think this shouldn't happen.
> >
> >Sascha
> >
> Thats was my idea too. But had no time to debug it out.
> As for_each_sg() iterate over the sg-list may its not set properly
> before - In an earlier post
> I ask for help but no-one returned so I quick fixed it.  Maybe now
> the bell is loud enough ;-)

Please try to track it further down. Does this happen every time you are
in this function or does it happen only every once in a while? Does it
happen in the first iteration of the loop? is it an SDIO card or regular
SD card?

Sascha

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