On Tue, Apr 23, 2019 at 07:06:06PM +1000, Stephen Rothwell wrote:
> Hi all,
>
> Today's linux-next merge of the akpm-current tree got a conflict in:
>
> arch/powerpc/mm/mmu_context_iommu.c
>
> between commits:
>
> eb9d7a62c386 ("powerpc/mm_iommu: Fix potential deadlock")
> 7a3a4d763837 ("powerpc/mm_iommu: Allow pinning large regions")
>
> from the powerpc-fixes tree and commit:
>
> 02f506bad7af ("mm/gup: replace get_user_pages_longterm() with FOLL_LONGTERM")
>
> from the akpm-current tree.
>
> I fixed it up (see below) and can carry the fix as necessary. This
Thanks Stephen
Looks good for my changes.
Acked-by: Ira Weiny <ira.weiny@xxxxxxxxx>
> is now fixed as far as linux-next is concerned, but any non trivial
> conflicts should be mentioned to your upstream maintainer when your tree
> is submitted for merging. You may also want to consider cooperating
> with the maintainer of the conflicting tree to minimise any particularly
> complex conflicts.
>
> --
> Cheers,
> Stephen Rothwell
>
> diff --cc arch/powerpc/mm/mmu_context_iommu.c
> index 8330f135294f,755fe7adc0d8..000000000000
> --- a/arch/powerpc/mm/mmu_context_iommu.c
> +++ b/arch/powerpc/mm/mmu_context_iommu.c
> @@@ -135,27 -144,18 +131,28 @@@ static long mm_iommu_do_alloc(struct mm
> }
>
> down_read(&mm->mmap_sem);
> - ret = get_user_pages(ua, entries, FOLL_WRITE | FOLL_LONGTERM,
> - mem->hpages, NULL);
> + chunk = (1UL << (PAGE_SHIFT + MAX_ORDER - 1)) /
> + sizeof(struct vm_area_struct *);
> + chunk = min(chunk, entries);
> + for (entry = 0; entry < entries; entry += chunk) {
> + unsigned long n = min(entries - entry, chunk);
> +
> - ret = get_user_pages_longterm(ua + (entry << PAGE_SHIFT), n,
> - FOLL_WRITE, mem->hpages + entry, NULL);
> ++ ret = get_user_pages(ua + (entry << PAGE_SHIFT), n,
> ++ FOLL_WRITE | FOLL_LONGTERM,
> ++ mem->hpages + entry, NULL);
> + if (ret == n) {
> + pinned += n;
> + continue;
> + }
> + if (ret > 0)
> + pinned += ret;
> + break;
> + }
> up_read(&mm->mmap_sem);
> - if (ret != entries) {
> - /* free the reference taken */
> - for (i = 0; i < ret; i++)
> - put_page(mem->hpages[i]);
> -
> - vfree(mem->hpas);
> - kfree(mem);
> - ret = -EFAULT;
> - goto unlock_exit;
> + if (pinned != entries) {
> + if (!ret)
> + ret = -EFAULT;
> + goto free_exit;
> }
>
> pageshift = PAGE_SHIFT;
