The flush_cache_page() is supposed to be justified only if the page
is already placed in process page table, and that is done right after
flush_cache_page(). So using this interface is wrong. And there is
no need to invalite cache since it was non-present before in
remove_migration_pmd(). So just to remove it.
Signed-off-by: Muchun Song <[email protected]>
---
mm/huge_memory.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index f58524394dc1..45ede45b11f5 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -3207,7 +3207,6 @@ void remove_migration_pmd(struct page_vma_mapped_walk *pvmw, struct page *new)
if (pmd_swp_uffd_wp(*pvmw->pmd))
pmde = pmd_wrprotect(pmd_mkuffd_wp(pmde));
- flush_cache_range(vma, mmun_start, mmun_start + HPAGE_PMD_SIZE);
if (PageAnon(new))
page_add_anon_rmap(new, vma, mmun_start, true);
else
@@ -3215,6 +3214,8 @@ void remove_migration_pmd(struct page_vma_mapped_walk *pvmw, struct page *new)
set_pmd_at(mm, mmun_start, pvmw->pmd, pmde);
if ((vma->vm_flags & VM_LOCKED) && !PageDoubleMap(new))
mlock_vma_page(new);
+
+ /* No need to invalidate - it was non-present before */
update_mmu_cache_pmd(vma, address, pvmw->pmd);
}
#endif
--
2.11.0
On 21 Jan 2022, at 3:13, Muchun Song wrote:
> The flush_cache_page() is supposed to be justified only if the page
> is already placed in process page table, and that is done right after
> flush_cache_page(). So using this interface is wrong. And there is
> no need to invalite cache since it was non-present before in
> remove_migration_pmd(). So just to remove it.
>
> Signed-off-by: Muchun Song <[email protected]>
> ---
> mm/huge_memory.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index f58524394dc1..45ede45b11f5 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c
> @@ -3207,7 +3207,6 @@ void remove_migration_pmd(struct page_vma_mapped_walk *pvmw, struct page *new)
> if (pmd_swp_uffd_wp(*pvmw->pmd))
> pmde = pmd_wrprotect(pmd_mkuffd_wp(pmde));
>
> - flush_cache_range(vma, mmun_start, mmun_start + HPAGE_PMD_SIZE);
> if (PageAnon(new))
> page_add_anon_rmap(new, vma, mmun_start, true);
> else
> @@ -3215,6 +3214,8 @@ void remove_migration_pmd(struct page_vma_mapped_walk *pvmw, struct page *new)
> set_pmd_at(mm, mmun_start, pvmw->pmd, pmde);
> if ((vma->vm_flags & VM_LOCKED) && !PageDoubleMap(new))
> mlock_vma_page(new);
> +
> + /* No need to invalidate - it was non-present before */
> update_mmu_cache_pmd(vma, address, pvmw->pmd);
> }
> #endif
LGTM. Thanks. Reviewed-by: Zi Yan <[email protected]>
--
Best Regards,
Yan, Zi