Re: [PATCH v16 13/25] mm: pagewalk: Don't lock PTEs for walk_page_range_novma()
From: Qian Cai
Date: Wed Dec 11 2019 - 12:19:39 EST
> On Dec 11, 2019, at 10:54 AM, Steven Price <Steven.Price@xxxxxxx> wrote:
> I believe this is a false positive (although the trace here is useless).
> This patch adds a conditional lock/unlock:
> pte = walk->no_vma ? pte_offset_map(pmd, addr) :
> pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
> if (!walk->no_vma)
> I'm not sure how to match sparse happy about that. Is the only option to
> have two versions of the walk_pte_range() function? One which takes the
> lock and one which doesn't.
Or just ignore the sparse false positive without complicating the code further.