Re: [PATCH 8/8] binder: use per-vma lock in page installation

[Carlos Llamas]

On Tue, Nov 05, 2024 at 08:02:50PM +0000, Carlos Llamas wrote:
> +static struct page *binder_page_lookup(struct mm_struct *mm,
> +				       struct vm_area_struct *vma,
> +				       unsigned long addr,
> +				       bool mm_locked)
> +{
> +	struct folio_walk fw;
> +	struct page *page;
> +
> +	/* folio_walk_start() requires the mmap_lock */
> +	if (!mm_locked)
> +		mmap_read_lock(mm);
> +
> +	if (!folio_walk_start(&fw, vma, addr, 0))
> +		return NULL;

Just realized that mmap_lock need to be released if folio_walk_start()
fails and !mm_locked. I'll add the fix for v2.