Hi Matthew,
On Sun, Sep 10, 2023 at 04:02:32AM +0100, Matthew Wilcox wrote:
> On Sat, Sep 09, 2023 at 10:12:48AM -0700, syzbot wrote:
> > commit 617c28ecab22d98a3809370eb6cb50fa24b7bfe1
> > Author: Yin Fengwei <fengwei.yin@xxxxxxxxx>
> > Date: Wed Aug 2 15:14:05 2023 +0000
> >
> > filemap: batch PTE mappings
>
> Hmm ... I don't know if this is the bug, but ...
This is Fengwei. Sorry for replying with my private email. I can't access
my compony email now.
Yes. This is a bug. But I think it just impact the performance.
I will look at this regression. Thanks and sorry for the trouble.
Regards
Yin, Fengwei
>
> #syz test
>
> diff --git a/mm/filemap.c b/mm/filemap.c
> index 582f5317ff71..580d0b2b1a7c 100644
> --- a/mm/filemap.c
> +++ b/mm/filemap.c
> @@ -3506,7 +3506,7 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf,
> if (count) {
> set_pte_range(vmf, folio, page, count, addr);
> folio_ref_add(folio, count);
> - if (in_range(vmf->address, addr, count))
> + if (in_range(vmf->address, addr, count * PAGE_SIZE))
> ret = VM_FAULT_NOPAGE;
> }
>
> @@ -3520,7 +3520,7 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf,
> if (count) {
> set_pte_range(vmf, folio, page, count, addr);
> folio_ref_add(folio, count);
> - if (in_range(vmf->address, addr, count))
> + if (in_range(vmf->address, addr, count * PAGE_SIZE))
> ret = VM_FAULT_NOPAGE;
> }
>
>
>
