Re: [PATCH v2] powerpc: warn on emulation of dcbz instruction in kernel mode
From: Christoph Hellwig
Date: Thu Aug 22 2024 - 01:32:54 EST
On Thu, Aug 22, 2024 at 05:25:10AM +0000, LEROY Christophe wrote:
> > and this results in a call to dma_direct_allocation(), which has one
> > innocent looking memset():
>
>
> memset() can't be used on non-cached memory, memset_io() has to be used
> instead.
No, we use memset on uncached memory all the time. Note that uncached
memory != __iomem memory, for which you DO have to use memset_io.