On Thu, Apr 08, 2021 at 04:20:54PM +0200, Siddharth Chandrasekaran wrote: > On Thu, Apr 08, 2021 at 02:05:53PM +0200, Vitaly Kuznetsov wrote: > > Siddharth Chandrasekaran <sidcha@xxxxxxxxx> writes: > > > > > Now that all extant hypercalls that can use XMM registers (based on > > > spec) for input/outputs are patched to support them, we can start > > > advertising this feature to guests. > > > > > > Cc: Alexander Graf <graf@xxxxxxxxxx> > > > Cc: Evgeny Iakovlev <eyakovl@xxxxxxxxx> > > > Signed-off-by: Siddharth Chandrasekaran <sidcha@xxxxxxxxx> > > > --- > > > arch/x86/include/asm/hyperv-tlfs.h | 4 ++-- > > > arch/x86/kvm/hyperv.c | 1 + > > > 2 files changed, 3 insertions(+), 2 deletions(-) > > > > > > diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h > > > index e6cd3fee562b..1f160ef60509 100644 > > > --- a/arch/x86/include/asm/hyperv-tlfs.h > > > +++ b/arch/x86/include/asm/hyperv-tlfs.h > > > @@ -49,10 +49,10 @@ > > > /* Support for physical CPU dynamic partitioning events is available*/ > > > #define HV_X64_CPU_DYNAMIC_PARTITIONING_AVAILABLE BIT(3) > > > /* > > > - * Support for passing hypercall input parameter block via XMM > > > + * Support for passing hypercall input and output parameter block via XMM > > > * registers is available > > > */ > > > -#define HV_X64_HYPERCALL_PARAMS_XMM_AVAILABLE BIT(4) > > > +#define HV_X64_HYPERCALL_PARAMS_XMM_AVAILABLE BIT(4) | BIT(15) > > > > TLFS 6.0b states that there are two distinct bits for input and output: > > > > CPUID Leaf 0x40000003.EDX: > > Bit 4: support for passing hypercall input via XMM registers is available. > > Bit 15: support for returning hypercall output via XMM registers is available. > > > > and HV_X64_HYPERCALL_PARAMS_XMM_AVAILABLE is not currently used > > anywhere, I'd suggest we just rename > > > > HV_X64_HYPERCALL_PARAMS_XMM_AVAILABLE to HV_X64_HYPERCALL_XMM_INPUT_AVAILABLE > > and add HV_X64_HYPERCALL_XMM_OUTPUT_AVAILABLE (bit 15). > > That is how I had it initially; but then noticed that we would never > need to use either of them separately. So it seemed like a reasonable > abstraction to put them together. > They are two separate things in TLFS. Please use two macros here. Wei.
