Re: [PATCH 1/2] drm/ttm: use the same attributes when freeing d_page->vaddr

From: Koenig, Christian
Date: Thu Jul 18 2019 - 03:56:07 EST


Am 18.07.19 um 09:21 schrieb Fuqian Huang:
> Koenig, Christian <Christian.Koenig@xxxxxxx> æ 2019å7æ16æéä äå9:38åéï
>> Am 11.07.19 um 05:10 schrieb Fuqian Huang:
>>> In function __ttm_dma_alloc_page(), d_page->addr is allocated
>>> by dma_alloc_attrs() but freed with use dma_free_coherent() in
>>> __ttm_dma_free_page().
>>> Use the correct dma_free_attrs() to free d_page->vaddr.
>>>
>>> Signed-off-by: Fuqian Huang <huangfq.daxian@xxxxxxxxx>
>> Reviewed-by: Christian KÃnig <christian.koenig@xxxxxxx>
>>
>> How do you want to upstream that? Should I pull it into our tree?
> I just came across this misuse case accidentally.
> I am not very clear about 'How to upstream that'.
> Are there more than one way to upstream the code and fix the problem?

Well I can add it to the TTM tree which send to David or it could be
pulled through some other way towards Linus.

> From my side, it is ok that you pull it into your tree and fix it or
> fix it in other way.
> :) It will be fine if the problem is fixed.

Ok, fine with me :)

Christian.

>
> Thanks.
>
>> Thanks,
>> Christian.
>>
>>> ---
>>> drivers/gpu/drm/ttm/ttm_page_alloc_dma.c | 6 +++++-
>>> 1 file changed, 5 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c
>>> index d594f7520b7b..7d78e6deac89 100644
>>> --- a/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c
>>> +++ b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c
>>> @@ -285,9 +285,13 @@ static int ttm_set_pages_caching(struct dma_pool *pool,
>>>
>>> static void __ttm_dma_free_page(struct dma_pool *pool, struct dma_page *d_page)
>>> {
>>> + unsigned long attrs = 0;
>>> dma_addr_t dma = d_page->dma;
>>> d_page->vaddr &= ~VADDR_FLAG_HUGE_POOL;
>>> - dma_free_coherent(pool->dev, pool->size, (void *)d_page->vaddr, dma);
>>> + if (pool->type & IS_HUGE)
>>> + attrs = DMA_ATTR_NO_WARN;
>>> +
>>> + dma_free_attrs(pool->dev, pool->size, (void *)d_page->vaddr, dma, attrs);
>>>
>>> kfree(d_page);
>>> d_page = NULL;