Re: [PATCH 6/8] iommu/intel: Add a gfp parameter to alloc_pgtable_page()

[Jason Gunthorpe]

On Tue, Jan 17, 2023 at 03:35:08AM +0000, Tian, Kevin wrote:
> > From: Jason Gunthorpe <j...@nvidia.com>
> > Sent: Saturday, January 7, 2023 12:43 AM
> > 
> > @@ -2676,7 +2676,7 @@ static int copy_context_table(struct intel_iommu
> > *iommu,
> >                     if (!old_ce)
> >                             goto out;
> > 
> > -                   new_ce = alloc_pgtable_page(iommu->node);
> > +                   new_ce = alloc_pgtable_page(iommu->node,
> > GFP_KERNEL);
> 
> GFP_ATOMIC

Can't be:

                        old_ce = memremap(old_ce_phys, PAGE_SIZE,
                                        MEMREMAP_WB);
                        if (!old_ce)
                                goto out;

                        new_ce = alloc_pgtable_page(iommu->node, GFP_KERNEL);
                        if (!new_ce)

memremap() is sleeping.

And the only caller is:

        ctxt_tbls = kcalloc(ctxt_table_entries, sizeof(void *), GFP_KERNEL);
        if (!ctxt_tbls)
                goto out_unmap;

        for (bus = 0; bus < 256; bus++) {
                ret = copy_context_table(iommu, &old_rt[bus],
                                         ctxt_tbls, bus, ext);

Jason