Hi,
On Mon, Aug 19, 2024 at 4:40 PM Doug Anderson <dianders@xxxxxxxxxxxx> wrote:
>
> Hi,
>
> On Mon, Aug 19, 2024 at 12:30 AM Sibi Sankar <quic_sibis@xxxxxxxxxxx> wrote:
> >
> > Any write access to the IMEM region when the Q6 is setting up XPU
> > protection on it will result in a XPU violation. Fix this by ensuring
> > IMEM writes related to the MBA post-mortem logs happen before the Q6
> > is brought out of reset.
> >
> > Fixes: 318130cc9362 ("remoteproc: qcom_q6v5_mss: Add MBA log extraction support")
> > Signed-off-by: Sibi Sankar <quic_sibis@xxxxxxxxxxx>
> > ---
> > drivers/remoteproc/qcom_q6v5_mss.c | 6 +++---
> > 1 file changed, 3 insertions(+), 3 deletions(-)
>
> As discussed offlist, this isn't a perfect fix since writes to this
> IMEM could happen by other drivers and those could still cause things
> to go boom if they run in parallel with this driver. That being said:
> * It seems like a more proper fix needs a coordinated effort between a
> device's built-in firmware and the modem firmware. This is difficult /
> near impossible to get done properly.
> * Even if we do a more proper fix, making this change won't hurt.
> * This change will immediately improve things by avoiding the XPU
> violation in the most common case.
>
> I've confirmed that the test case I had where things were going boom
> is fixed. Thus:
>
> Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
> Tested-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
Just checking in to see if there's anything else needed for this patch
to land. Thanks! :-)
-Doug
