Re: [PATCH v1 0/2] Fixes for kmemleak tracking with CMA regions

Andrew Morton
2023-01-24T20:20:22Z

On Tue, 24 Jan 2023 15:48:57 +0000 Catalin Marinas <catalin.marinas@arm.com> wrote:

> Thanks for digging this out. This patch shouldn't have ended up upstream
> (commit 972fa3a7c17c "mm: kmemleak: alloc gray object for reserved
> region with direct map"). I thought both Calvin Zhang and I agreed that
> it's not the correct approach (not even sure there was a real problem to
> fix).
>
> Do you still get the any faults with the above commit reverted? I'd
> prefer this if it works rather than adding unnecessary
> kmemleak_alloc/free callbacks that pretty much cancel each-other.
>
> > I'm not sure if that commit is appropriate, given that reserved regions
> > that still have their direct mappings intact may be used for DMA, which
> > isn't appropriate for kmemleak scanning.
>
> It's not. I think it should be reverted.

Could someone please send along a patch to revert this, along
with the explanation for doing so? And please consider a cc:stable.