On Thu, Feb 01, 2024 at 04:32:27PM +0800,
Yuan Yao <yuan.yao@xxxxxxxxxxxxxxx> wrote:
...
> > +static int __tdx_reclaim_page(hpa_t pa)
> > +{
> > + struct tdx_module_args out;
> > + u64 err;
> > +
> > + do {
> > + err = tdh_phymem_page_reclaim(pa, &out);
> > + /*
> > + * TDH.PHYMEM.PAGE.RECLAIM is allowed only when TD is shutdown.
> > + * state. i.e. destructing TD.
> > + * TDH.PHYMEM.PAGE.RECLAIM requires TDR and target page.
> > + * Because we're destructing TD, it's rare to contend with TDR.
> > + */
> > + } while (unlikely(err == (TDX_OPERAND_BUSY | TDX_OPERAND_ID_RCX)));
>
> v16 changed to tdx module 1.5, so here should be TDX_OPERAND_ID_TDR, value 128ULL.
We should handle both RCX(SEPT) and TDR. So I make it err == RCX || err == TDR.
...
> > +static int __tdx_td_init(struct kvm *kvm)
> > +{
> > + struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm);
> > + cpumask_var_t packages;
> > + unsigned long *tdcs_pa = NULL;
> > + unsigned long tdr_pa = 0;
> > + unsigned long va;
> > + int ret, i;
> > + u64 err;
> > +
> > + ret = tdx_guest_keyid_alloc();
> > + if (ret < 0)
> > + return ret;
> > + kvm_tdx->hkid = ret;
> > +
> > + va = __get_free_page(GFP_KERNEL_ACCOUNT);
> > + if (!va)
> > + goto free_hkid;
> > + tdr_pa = __pa(va);
> > +
> > + tdcs_pa = kcalloc(tdx_info->nr_tdcs_pages, sizeof(*kvm_tdx->tdcs_pa),
> > + GFP_KERNEL_ACCOUNT | __GFP_ZERO);
> > + if (!tdcs_pa)
> > + goto free_tdr;
> > + for (i = 0; i < tdx_info->nr_tdcs_pages; i++) {
> > + va = __get_free_page(GFP_KERNEL_ACCOUNT);
> > + if (!va)
> > + goto free_tdcs;
> > + tdcs_pa[i] = __pa(va);
> > + }
> > +
> > + if (!zalloc_cpumask_var(&packages, GFP_KERNEL)) {
> > + ret = -ENOMEM;
> > + goto free_tdcs;
> > + }
> > + cpus_read_lock();
> > + /*
> > + * Need at least one CPU of the package to be online in order to
> > + * program all packages for host key id. Check it.
> > + */
> > + for_each_present_cpu(i)
> > + cpumask_set_cpu(topology_physical_package_id(i), packages);
> > + for_each_online_cpu(i)
> > + cpumask_clear_cpu(topology_physical_package_id(i), packages);
> > + if (!cpumask_empty(packages)) {
> > + ret = -EIO;
> > + /*
> > + * Because it's hard for human operator to figure out the
> > + * reason, warn it.
> > + */
> > +#define MSG_ALLPKG "All packages need to have online CPU to create TD. Online CPU and retry.\n"
> > + pr_warn_ratelimited(MSG_ALLPKG);
> > + goto free_packages;
> > + }
>
> Generate/release hkid both requests to have "cpumask of at least 1
> cpu per each node", how about add one helper for this ? The helper also
> checks the cpus_read_lock() is held and return the cpumask if at least
> 1 cpu is online per node, thus this init funciotn can be simplified and
> become more easy to review.
We don't need cpumask to release hkid. So only tdx_td_init() needs cpumask
allocation. So I didn't to bother create a helper function with v19.
--
Isaku Yamahata <isaku.yamahata@xxxxxxxxxxxxxxx>
