Re: [PATCH mm-hotfixes v3 2/4] x86/mm/pat: acquire mmap lock on page table free to avoid ptdump UAF

[Lorenzo Stoakes (ARM)]

On Tue, Jul 14, 2026 at 10:29:51AM -0700, Dave Hansen wrote:
> On 7/14/26 10:24, Lorenzo Stoakes wrote:
> ...
> > Resolve the issue by acquiring the mmap read lock on init_mm which prevents
> > a concurrent ptdump as it acquires the write lock.
>
> The move over to locking on init_mm instead of current->mm fixes the
> earlier issues I saw with this. Thanks for doing that!

No worries! It's kinda laying foundations and then addressing things with other
patches in the series, which is why Mike's suggestion of combining all the
patches in one series was clearly the right way to go :)

>
> Reviewed-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
>

Thanks!

Cheers, Lorenzo