On Tue, Sep 4, 2018 a> +/** > > > + va = ioremap_cache(addr, size); > > > + if (!va) > > > + return -ENOMEM; > > > > I'm not sure this is a right API. Do we operate with memory? Does it > > have I/O side effects? > > If no, memremap() would be better to use. > > Preserving __iomem is desirable. There aren't side effects per se, > but direct non-enclave accesses to the EPC get abort page semantics so > the kernel shouldn't be directly dereferencing a pointer to the EPC. > Though by that argument, sgx_epc_bank.va, sgx_epc_addr's return and > all ENCLS helpers should be tagged __iomem. Why? Does it related to *any* I/O? -- With Best Regards, Andy Shevchenko