On Thu, Jul 23, 2020 at 01:02:43AM +0200, Thomas Gleixner wrote: > Ricardo Neri <ricardo.neri-calderon@xxxxxxxxxxxxxxx> writes: > > On Tue, Jul 07, 2020 at 09:36:15AM -0700, Andy Lutomirski wrote: > >> On Mon, Jul 6, 2020 at 7:21 PM Cathy Zhang <cathy.zhang@xxxxxxxxx> wrote: > >> > > >> > This instruction gives software a way to force the processor to complete > >> > all modifications to flags, registers and memory from previous instructions > >> > and drain all buffered writes to memory before the next instruction is > >> > fetched and executed. > >> > > >> > The same effect can be obtained using the cpuid instruction. However, > >> > cpuid causes modification on the eax, ebx, ecx, and ecx regiters; it > >> > also causes a VM exit. > >> > > >> > A processor supports SERIALIZE instruction if CPUID.0x0x.0x0:EDX[14] is > >> > present. The CPU feature flag is shown as "serialize" in /proc/cpuinfo. > >> > > >> > Detailed information on the instructions and CPUID feature flag SERIALIZE > >> > can be found in the latest Intel Architecture Instruction Set Extensions > >> > and Future Features Programming Reference and Intel 64 and IA-32 > >> > Architectures Software Developer's Manual. > >> > >> Can you also wire this up so sync_core() uses it? > > > > I am cc'ing Fenghua, who has volunteered to work on this. Addind support > > for SERIALIZE in sync_core() should not block merging these patches, > > correct? > > Come on. We are not serving KVM first before making this usable on bare > metal. Hi Thomas, I ended up implementing support for SERIALIZE in sync_core() I will be posting patches for this in the next few days. Thanks and BR, Ricardo
