Re: [PATCH] coresight: tpdm: fix invalid MMIO access issue

[Jie Gan]

Hi Leo,

On 4/7/2026 6:35 PM, Leo Yan wrote:
> Hi Jie,
>
> On Tue, Apr 07, 2026 at 04:33:22PM +0800, Jie Gan wrote:
> > On 4/7/2026 4:10 PM, Leo Yan wrote:
> > > On Tue, Apr 07, 2026 at 12:47:11PM +0800, Jie Gan wrote:
> > > > Create the csdev_access struct only when a valid MMIO resource is
> > > > available. In tpdm_probe(), base is uninitialized for static TPDM
> > > > instances that lack an MMIO resource, causing csdev_access to be
> > > > created with a garbage address and potentially leading to
> > > > unexpected issues.
> > >
> > > This patch itself is fine for me.  However, I am wandering if this
> > > is sufficient.
> > >
> > > As mentioned "potentially leading to unexpected issues", can I
> > > understand some code pieces access register with uninitialized base?
> > > If so, you would also explictly add coresight_is_static_tpdm() to
> > > prevent register access.
> >
> > Actually, we havent MMIO access for the static TPDM device, So no issues are
> > observed. The commit message here may be misleading. do I need rephrase the
> > commit message?
>
> Yes, good to clarify a bit in commit log:
>
>    "So far there has no register access for static instance, but this
>     change helps mitigate potential risks in the future."
>
> With this:
>
> Reviewed-by: Leo Yan <leo.yan@xxxxxxx>

Well noted.

Thanks,
Jie