Re: [PATCH RFC 07/11] mm/mremap: use ptep_get() for the destination PTE
Alexander Gordeev <[email protected]>
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On Mon, Jul 27, 2026 at 05:46:58PM +0100, Muhammad Usama Anjum wrote: > move_ptes() directly dereferences new_ptep when checking that the > destination slot is empty. new_ptep now points to hw_pte_t table storage, > while pte_none() consumes a logical pte_t value. > > Read the destination entry through the standard ptep_get() accessor before > passing the logical value to pte_none(). > > Signed-off-by: Muhammad Usama Anjum <[email protected]> > --- > mm/mremap.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/mremap.c b/mm/mremap.c > index d966ee8248b6b..ecb90ccee6fdd 100644 > --- a/mm/mremap.c > +++ b/mm/mremap.c > @@ -264,7 +264,7 @@ static int move_ptes(struct pagetable_move_control *pmc, > > for (; old_addr < old_end; old_ptep += nr_ptes, old_addr += nr_ptes * PAGE_SIZE, > new_ptep += nr_ptes, new_addr += nr_ptes * PAGE_SIZE) { > - VM_WARN_ON_ONCE(!pte_none(*new_ptep)); > + VM_WARN_ON_ONCE(!pte_none(ptep_get(new_ptep))); Same as the previous patch, except that I did it already: https://lore.kernel.org/linux-mm/[email protected]/ > > nr_ptes = 1; > max_nr_ptes = (old_end - old_addr) >> PAGE_SHIFT; > -- > 2.47.3 >