On Wed, Apr 11, 2012 at 12:57 PM, Saravana Kannan <skannan@xxxxxxxxxxxxxx> wrote: > On 04/11/2012 10:59 AM, Turquette, Mike wrote: >> On Thu, Apr 5, 2012 at 6:30 PM, Saravana Kannan<skannan@xxxxxxxxxxxxxx> >> My only concern with this series is that platform clock code will >> access struct clk_hw members without the appropriate lock held (namely >> prepare_lock). I'm a bit worried that there might be a case where >> some clock code access clk_hw->name when clk_hw has somehow been >> destroyed/altered (e.g. if clk_put every finally gets implemented...). >> Besides clk_put are there any real instances where this might happen? > > This problem is true for any struct/field marked as __init_data. So, I don't > think this is a real problem. If someone is stupid enough to mark their data > as __init_data and access them later, then there is not much we can do. > Also, I believe the compiler throws out some warning when you try to access > __init_data from non-init code. I'm referring to platform clock code accessing clk_hw->name or clk_hw->parent_names AFTER the core code has copied the initialization data. So this isn't an __initdata problem as much as it is a design issue with exposing some members of struct clk_hw. I think that this is basically OK since the benefits of not having to use so many helpers functions in platform clock code is obvious and if a platform gets bitten by this then they will learn the hard way to honor the locking semantics outlined in Documentation/clk.txt >> I'll be pushing my fixes branch out to the list soon. Do you want to >> rebase this change on top of it taking into account the __initdata >> bits? > > I thought it might be easier for you to base your changes on top of my > patch. But I can try to rebase mine on top of your changes. Hopefully your > fixes aren't crazy big/complex. I don't think the fixes are a big deal, especially in the core code. > This is a busy week for me at work. I will try to send a patch in a day or > two. OK. I might take a swing at it myself if I have time. Regards, Mike -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
