Re: [PATCH v9 05/13] iommu/amd: Add function copy_dev_tables()

Baoquan He
2017-08-04T12:21:30Z

Hi Joerg,

Thanks for your reviewing!

On 08/04/17 at 02:09pm, Joerg Roedel wrote:
> Hi Baoquan,
>
> On Tue, Aug 01, 2017 at 07:37:21PM +0800, Baoquan He wrote:
> > + for_each_iommu(iommu) {
> > + /* All IOMMUs should use the same device table with the same size */
> > + lo = readl(iommu->mmio_base + MMIO_DEV_TABLE_OFFSET);
> > + hi = readl(iommu->mmio_base + MMIO_DEV_TABLE_OFFSET + 4);
> > + entry = (((u64) hi) << 32) + lo;
> > + if (last_entry && last_entry != entry) {
> > + pr_err("IOMMU:%d should use the same dev table as others!/n",
> > + iommu->index);
> > + return -1;
> > + }
> > + last_entry = entry;
> > +
> > + old_devtb_size = ((entry & ~PAGE_MASK) + 1) << 12;
> > + if (old_devtb_size != dev_table_size) {
> > + pr_err("The device table size of IOMMU:%d is not expected!/n",
> > + iommu->index);
> > + return -1;
> > + }
> > +
> > + if (copied)
> > + continue;
> > +
> > + old_devtb_phys = entry & PAGE_MASK;
> > + old_devtb = memremap(old_devtb_phys, dev_table_size, MEMREMAP_WB);
> > + if (!old_devtb)
> > + return -1;
>
> You forgot to check whether the old device table is also below 4GB.

I did it in patch 10/13. I think it's an sub-issue and can be explained
in a specific patch.

Thanks
Baoquan