Re: [PATCH v2] staging: tidspbridge: protect dmm_map properly

[Ohad Ben-Cohen]

On Tue, Dec 28, 2010 at 2:12 PM, Felipe Contreras
<felipe.contreras@xxxxxxxxx> wrote:
> On Tue, Dec 28, 2010 at 12:56 PM, Ohad Ben-Cohen <ohad@xxxxxxxxxx> wrote:
>> I still don't know how exactly you triggered the bug: is gst-dsp
>> multithreaded ? and one of its threads invoked proc_un_map() while
>> another thread called proc_begin_dma() ?
>
> I haven't investigated why that happens

Btw, I still think you should look into this.

The kernel panic will be solved, but you may still have a race there
that can lead to data corruption: if proc_un_map will be fast enough,
it will acquire the proc_lock mutex before proc_begin_dma(), and then
you will miss a cache operation.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/