On Mon, Sep 03, 2018 at 05:41:53PM +0300, Andy Shevchenko wrote: > On Mon, Aug 27, 2018 at 9:58 PM Jarkko Sakkinen > <jarkko.sakki...@linux.intel.com> wrote: > > > + 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. For documentation purposes, maybe it would be better to use __private or "#define __sgx_epc __iomem" and use that?
