On Wed, 31 May 2023, Jason Gunthorpe wrote:
> On Sun, May 28, 2023 at 11:16:16PM -0700, Hugh Dickins wrote:
> > There is a faint risk that __pte_offset_map(), on a 32-bit architecture
> > with a 64-bit pmd_t e.g. x86-32 with CONFIG_X86_PAE=y, would succeed on
> > a pmdval assembled from a pmd_low a
On Sun, May 28, 2023 at 11:16:16PM -0700, Hugh Dickins wrote:
> There is a faint risk that __pte_offset_map(), on a 32-bit architecture
> with a 64-bit pmd_t e.g. x86-32 with CONFIG_X86_PAE=y, would succeed on
> a pmdval assembled from a pmd_low and a pmd_high which never belonged
> together: their
On Sun, May 28, 2023 at 11:16:16PM -0700, Hugh Dickins wrote:
> +#if defined(CONFIG_GUP_GET_PXX_LOW_HIGH) && \
> + (defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RCU))
> +/*
> + * See the comment above ptep_get_lockless() in include/linux/pgtable.h:
> + * the barriers in pmdp_get_lockless() can
There is a faint risk that __pte_offset_map(), on a 32-bit architecture
with a 64-bit pmd_t e.g. x86-32 with CONFIG_X86_PAE=y, would succeed on
a pmdval assembled from a pmd_low and a pmd_high which never belonged
together: their combination not pointing to a page table at all, perhaps
not even a v