On Mon, Jun 12, 2017 at 6:42 AM, Song liwei <liwei.s...@windriver.com> wrote: > From: Liwei Song <liwei.s...@windriver.com> >
> Fix the following calltrace: No, you don't fix a call trace, you are fixing a bug. > This happen When run "i2cdetect -y 0" detect SMBus iSMT adapter. > > After finished I2C block read/write, when unmap the data buffer, > a wrong device address was pass to dma_unmap_single(), > the right > device address should be "dev" not "&adap->dev", the relation is > *(&adap->dev) == dev. This is confusing. You are telling that there are two copies of struct device here? Otherwise if one is a pointer to the real struct device, there shouldn't be a problem. > When come into Intel IOMMU routine, the wrong > devices address was operated. This basically duplicates what you have said previously. > To fix this, give dma_unmap_single() the "dev" parameter, just like > what dma_map_single() does, then unmap can find the right devices. Fix per se looks good, explanation is confusing. > > Signed-off-by: Liwei Song <liwei.s...@windriver.com> > --- > drivers/i2c/busses/i2c-ismt.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/i2c/busses/i2c-ismt.c b/drivers/i2c/busses/i2c-ismt.c > index 1db3e0d..605d44e 100644 > --- a/drivers/i2c/busses/i2c-ismt.c > +++ b/drivers/i2c/busses/i2c-ismt.c > @@ -585,7 +585,7 @@ static int ismt_access(struct i2c_adapter *adap, u16 addr, > > /* unmap the data buffer */ > if (dma_size != 0) > - dma_unmap_single(&adap->dev, dma_addr, dma_size, > dma_direction); > + dma_unmap_single(dev, dma_addr, dma_size, dma_direction); > > if (unlikely(!time_left)) { > dev_err(dev, "completion wait timed out\n"); > -- > 2.7.4 > -- With Best Regards, Andy Shevchenko