On 2/5/25 20:39, Ryan Roberts wrote:
> Fix callers that previously skipped calling arch_sync_kernel_mappings()
> if an error occurred during a pgtable update. The call is still required
> to sync any pgtable updates that may have occurred prior to hitting the
> error condition.
>
> These are theoretical bugs discovered during code review.
>
> Cc: <stable@xxxxxxxxxxxxxxx>
> Fixes: 2ba3e6947aed ("mm/vmalloc: track which page-table levels were modified")
> Fixes: 0c95cba49255 ("mm: apply_to_pte_range warn and fail if a large pte is encountered")
> Signed-off-by: Ryan Roberts <ryan.roberts@xxxxxxx>
This change could stand on its own and LGTM.
Reviewed-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
> ---
> mm/memory.c | 6 ++++--
> mm/vmalloc.c | 4 ++--
> 2 files changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/mm/memory.c b/mm/memory.c
> index 539c0f7c6d54..a15f7dd500ea 100644
> --- a/mm/memory.c
> +++ b/mm/memory.c
> @@ -3040,8 +3040,10 @@ static int __apply_to_page_range(struct mm_struct *mm, unsigned long addr,
> next = pgd_addr_end(addr, end);
> if (pgd_none(*pgd) && !create)
> continue;
> - if (WARN_ON_ONCE(pgd_leaf(*pgd)))
> - return -EINVAL;
> + if (WARN_ON_ONCE(pgd_leaf(*pgd))) {
> + err = -EINVAL;
> + break;
> + }
> if (!pgd_none(*pgd) && WARN_ON_ONCE(pgd_bad(*pgd))) {
> if (!create)
> continue;
> diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> index 6111ce900ec4..68950b1824d0 100644
> --- a/mm/vmalloc.c
> +++ b/mm/vmalloc.c
> @@ -604,13 +604,13 @@ static int vmap_small_pages_range_noflush(unsigned long addr, unsigned long end,
> mask |= PGTBL_PGD_MODIFIED;
> err = vmap_pages_p4d_range(pgd, addr, next, prot, pages, &nr, &mask);
> if (err)
> - return err;
> + break;
> } while (pgd++, addr = next, addr != end);
>
> if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
> arch_sync_kernel_mappings(start, end);
>
> - return 0;
> + return err;
> }
>
> /*
