[PATCH v5 1/4] iommu/shmobile: Add iommu driver for Renesas IPMMU modules

Joerg Roedel joro at 8bytes.org
Thu Jan 10 13:32:37 EST 2013


Hi,

On Mon, Jan 07, 2013 at 07:11:58PM +0100, Laurent Pinchart wrote:
> > +		l2index = (iova >> 12) & 0xff;
> > +		spin_lock(&sh_domain->map_lock);
> > +		ret = l2alloc(sh_domain, l1index);
> 
> l2alloc calls dma_pool_alloc(GFP_KERNEL), that not safe in a non-sleepable 
> context. Do we need a spinlock here, or could a mutex do ?

iommu_map should work in any context, so a mutex will not work. Also the
memory allocations in that path should be GFP_ATOMIC instead of
GFP_KERNEL.

Other than that this driver looks good from an IOMMU-API perspective.
Please Cc me on future versions of this patch-set directly.

Thanks,

	Joerg




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