Re: [PATCH v2 0/5] x86/mm/pat: CPA fixes

["Lorenzo Stoakes (ARM)" <ljs@kernel.org>]

On Thu, Aug 13, 2026 at 08:35:21PM +0530, Nikunj A. Dadhania wrote:
>
> Tested v2 on a 512-guest concurrent boot harness across 200 iterations
> with no splats. Both crash signatures reported in [1] are no longer seen.
>
> Tested-by: Nikunj A Dadhania <nikunj@amd.com>

Thanks so much for the testing!

And all credit to Pedro for reporting and contributing the key commit that
resolves this issue :)

>
> Regards,
> Nikunj
>
> [1] https://lore.kernel.org/all/20260812063316.21371-1-nikunj@amd.com/
>
> > v1: https://patch.msgid.link/20260728-cpa-fixes-v1-0-2ed2352300b3@kernel.org
> >
> > ---
> > Lorenzo Stoakes (ARM) (3):
> >       x86/mm/pat: acquire init_mm write lock on collapse to avoid UAF
> >       x86/mm/pat: acquire init_mm read lock on attribute change to avoid UAF
> >       x86/mm/pat: allocate split page tables as kernel page tables
> >
> > Mike Rapoport (Microsoft) (1):
> >       x86/mm/pat: fix effective RW computation in lookup_address_in_pgd_attr()
> >
> > Pedro Falcato (1):
> >       x86/alternative: exclude text poking against change_page_attr()
> >
> >  arch/x86/kernel/alternative.c | 39 ++++++++++++++++++++++++---
> >  arch/x86/mm/pat/set_memory.c  | 61 +++++++++++++++++++++++++++++++------------
> >  include/linux/mmap_lock.h     |  2 ++
> >  3 files changed, 83 insertions(+), 19 deletions(-)
> > ---
> > base-commit: 7da514d819a0afb148634aac92b3d190f34947c3
> > change-id: 20260727-cpa-fixes-d3c73c075672
> >
> > --
> > Sincerely yours,
> > Mike.
> >
>

--
Cheers, Lorenzo