2023-05-22 05:09:08

by Hugh Dickins

Subject: [PATCH 12/31] mm/vmalloc: vmalloc_to_page() use pte_offset_kernel()

vmalloc_to_page() was using pte_offset_map() (followed by pte_unmap()),
but it's intended for userspace page tables: prefer pte_offset_kernel().

Signed-off-by: Hugh Dickins <[email protected]>
---
mm/vmalloc.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 9683573f1225..741722d247d5 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -703,11 +703,10 @@ struct page *vmalloc_to_page(const void *vmalloc_addr)
if (WARN_ON_ONCE(pmd_bad(*pmd)))
return NULL;

- ptep = pte_offset_map(pmd, addr);
+ ptep = pte_offset_kernel(pmd, addr);
pte = *ptep;
if (pte_present(pte))
page = pte_page(pte);
- pte_unmap(ptep);

return page;
}
--
2.35.3

2023-05-22 07:43:39

by Lorenzo Stoakes

Subject: Re: [PATCH 12/31] mm/vmalloc: vmalloc_to_page() use pte_offset_kernel()

On Sun, May 21, 2023 at 10:04:07PM -0700, Hugh Dickins wrote:
> vmalloc_to_page() was using pte_offset_map() (followed by pte_unmap()),
> but it's intended for userspace page tables: prefer pte_offset_kernel().
>
> Signed-off-by: Hugh Dickins <[email protected]>
> ---
> mm/vmalloc.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> index 9683573f1225..741722d247d5 100644
> --- a/mm/vmalloc.c
> +++ b/mm/vmalloc.c
> @@ -703,11 +703,10 @@ struct page *vmalloc_to_page(const void *vmalloc_addr)
> if (WARN_ON_ONCE(pmd_bad(*pmd)))
> return NULL;
>
> - ptep = pte_offset_map(pmd, addr);
> + ptep = pte_offset_kernel(pmd, addr);
> pte = *ptep;
> if (pte_present(pte))
> page = pte_page(pte);
> - pte_unmap(ptep);
>
> return page;
> }
> --
> 2.35.3
>

Looks good to me,

Reviewed-by: Lorenzo Stoakes <[email protected]>