Re: [PATCH v2] ARM: DMA: Fix kzalloc flags in __dma_alloc

From: Rabin Vincent
Date: Fri Mar 18 2016 - 06:38:51 EST


On Fri, Mar 18, 2016 at 06:28:49PM +0900, Alexandre Courbot wrote:
> Commit 19e6e5e5392b ("ARM: 8547/1: dma-mapping: store buffer
> information") allocates a structure meant for internal buffer management
> with the GFP flags of the buffer itself. This can trigger the following
> safeguard in the slab/slub allocator:
>
> if (unlikely(flags & GFP_SLAB_BUG_MASK)) {
> pr_emerg("gfp: %u\n", flags & GFP_SLAB_BUG_MASK);
> BUG();
> }
>
> Fix this by filtering the flags that make the slab allocator unhappy.
>
> Signed-off-by: Alexandre Courbot <acourbot@xxxxxxxxxx>
> Cc: Rabin Vincent <rabin@xxxxxx>
> ---
> Changes since v1:
> - Filter flags that may cause problem instead of forcing GFP_KERNEL
> (and risk sleeping in atomic context), as suggested by Rabin.

Acked-by: Rabin Vincent <rabin@xxxxxx>

Thanks.