Re: [PATCH 1/1] x86/mm: fix incomplete page-table invalidation with TCE

[Lance Yang]

On 2026/10/5 17:57, Andrew Cooper wrote:
> On 05/10/2026 9:32 am, Lance Yang wrote:
> > On 2026/10/5 16:19, Andrew Cooper wrote:
> > > On 05/10/2026 8:29 am, Lance Yang wrote:
> > > > > Did you repro any bug related to this? The functionality is perhaps
> > > > > underspecified in the AMD manual.
> > > >
> > > > TBH, I don't have a reproducer yet. Just LLM stumbled upon this while
> > > > I was investigating another memory corruption issue [1].
> > > >
> > > > [1]
> > > > https://lore.kernel.org/linux-mm/arY1Wq6R9OY20ans@xxxxxxxxxxxxxxxxx/#t
> > >
> > > What hardware are you running on?
> > >
> > > That looks like the Zen5 issue, for which you want either the latest
> > > microcode out of linux-firmware and/or
> > > https://lore.kernel.org/r/20261002211617.1001617-1-bp@xxxxxxxxxx
> > >
> > > TCE is a no-op in Zen1 and later, so unless you're on older hardware, it
> > > won't be that.
> >
> > Just to clarify ... these are two separate issues.
> >
> > I mentioned [1] only to explain how this came up while investigating
> > something else. I'm not claiming that TCE caused the corruption reported
> > there :)
>
> Please can you answer the question.  Which CPU are you seeing this on?

Which CPU? None so far. As I said, I don't have a reproducer. I'm trying
to make sense of what the manual says and what the code does ...