On Sat, Sep 1, 2012 at 1:14 PM, shiraz hashim <shiraz.linux.kernel@xxxxxxxxx> wrote: > Hi Roland, > > On Wed, Aug 22, 2012 at 7:19 PM, Roland Stigge <stigge@xxxxxxxxx> wrote: >> @@ -2016,6 +2030,8 @@ pl022_probe(struct amba_device *adev, co >> pl022->master_info = platform_info; >> pl022->adev = adev; >> pl022->vendor = id->data; >> + /* Point chipselects to allocated memory beyond the main struct */ >> + pl022->chipselects = (int *) pl022 + sizeof(struct pl022); > > This is going beyond memory allocated for chipselects > as it adds 4 * sizeof(struct pl022) bytes to pl022. Yes that is why the allocation looks like this: + master = spi_alloc_master(dev, sizeof(struct pl022) + sizeof(int) * + platform_info->num_chipselect); > pl022->chipselects = (int *) &pl022[1]; > can be musch safer. I see absolutely no sematic difference between these two methods to reach the first position beyond the first struct. If we're gonna be debating this it's a safe sign that this is not a good design pattern at all, so then it is better to simply devm_kzalloc(sizeof(int) * platform_info->num_chipselect); separately. (But I'm happy with the patch as it is. And the other way too, since I'm not very picky.) Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
