On Wed, Nov 09, 2016 at 06:35:13PM -0600, Tom Lendacky wrote: > +/* > + * AMD Secure Memory Encryption (SME) can reduce the size of the physical > + * address space if it is enabled, even if memory encryption is not active. > + * Adjust x86_phys_bits if SME is enabled. > + */ > +static void phys_bits_adjust(struct cpuinfo_x86 *c) > +{ Better call this function amd_sme_phys_bits_adjust(). This name makes it clear at the call-site why it is there and what it does. > + u32 eax, ebx, ecx, edx; > + u64 msr; > + > + if (c->x86_vendor != X86_VENDOR_AMD) > + return; > + > + if (c->extended_cpuid_level < 0x8000001f) > + return; > + > + /* Check for SME feature */ > + cpuid(0x8000001f, &eax, &ebx, &ecx, &edx); > + if (!(eax & 0x01)) > + return; Maybe add a comment here why you can't use cpu_has (yet). -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>