Saurabh Sengar <ssengar@xxxxxxxxxxxxxxxxxxx> writes:
> For non VTL platforms vtl is always 0, and there is no need of
> get_vtl function. For VTL platforms get_vtl should always succeed
> and should return the correct VTL.
>
> Signed-off-by: Saurabh Sengar <ssengar@xxxxxxxxxxxxxxxxxxx>
> ---
> arch/x86/hyperv/hv_init.c | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
> index 783ed339f341..e589c240565a 100644
> --- a/arch/x86/hyperv/hv_init.c
> +++ b/arch/x86/hyperv/hv_init.c
> @@ -416,8 +416,8 @@ static u8 __init get_vtl(void)
> if (hv_result_success(ret)) {
> ret = output->as64.low & HV_X64_VTL_MASK;
> } else {
> - pr_err("Failed to get VTL(%lld) and set VTL to zero by default.\n", ret);
> - ret = 0;
> + pr_err("Failed to get VTL(error: %lld) exiting...\n", ret);
Nitpick: arch/x86/hyperv/hv_init.c lacks pr_fmt so the message won't get
prefixed with "Hyper-V". I'm not sure 'VTL' abbreviation has the only,
Hyper-V specific meaning. I'd suggest we add
#define pr_fmt(fmt) "Hyper-V: " fmt
to the beginning of the file.
> + BUG();
> }
>
> local_irq_restore(flags);
> @@ -604,8 +604,10 @@ void __init hyperv_init(void)
> hv_query_ext_cap(0);
>
> /* Find the VTL */
> - if (!ms_hyperv.paravisor_present && hv_isolation_type_snp())
> + if (IS_ENABLED(CONFIG_HYPERV_VTL_MODE))
> ms_hyperv.vtl = get_vtl();
> + else
> + ms_hyperv.vtl = 0;
Is 'else' branch really needed? 'ms_hyperv' seems to be a statically
allocated global. But instead of doing this, what about putting the
whole get_vtl() funtion under '#if (IS_ENABLED(CONFIG_HYPERV_VTL_MODE))', i.e.:
#if IS_ENABLED(CONFIG_HYPERV_VTL_MODE)
static u8 __init get_vtl(void)
{
u64 control = HV_HYPERCALL_REP_COMP_1 | HVCALL_GET_VP_REGISTERS;
...
}
#else
static inline get_vtl(void) { return 0; }
#endif
and then we can always do
ms_hyperv.vtl = get_vtl();
unconditionally?
>
> return;
--
Vitaly
