On 1/8/2025 2:21 PM, Roman Kisel wrote: > The Top-Level Functional Specification for Hyper-V, Section 3.6 [1, 2], > disallows overlapping of the input and output hypercall areas, and > hv_vtl_apicid_to_vp_id() overlaps them. > > Use the output hypercall page of the current vCPU for the hypercall. > > [1] https://learn.microsoft.com/en-us/virtualization/hyper-v-on-windows/tlfs/hypercall-interface > [2] https://github.com/MicrosoftDocs/Virtualization-Documentation/tree/main/tlfs > > Reported-by: Michael Kelley <mhklinux@xxxxxxxxxxx> > Closes: https://lore.kernel.org/lkml/SN6PR02MB4157B98CD34781CC87A9D921D40D2@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/ > Signed-off-by: Roman Kisel <romank@xxxxxxxxxxxxxxxxxxx> > Reviewed-by: Easwar Hariharan <eahariha@xxxxxxxxxxxxxxxxxxx> > --- > arch/x86/hyperv/hv_vtl.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/x86/hyperv/hv_vtl.c b/arch/x86/hyperv/hv_vtl.c > index 04775346369c..4e1b1e3b5658 100644 > --- a/arch/x86/hyperv/hv_vtl.c > +++ b/arch/x86/hyperv/hv_vtl.c > @@ -189,7 +189,7 @@ static int hv_vtl_apicid_to_vp_id(u32 apic_id) > input->partition_id = HV_PARTITION_ID_SELF; > input->apic_ids[0] = apic_id; > > - output = (u32 *)input; > + output = *this_cpu_ptr(hyperv_pcpu_output_arg); > > control = HV_HYPERCALL_REP_COMP_1 | HVCALL_GET_VP_ID_FROM_APIC_ID; > status = hv_do_hypercall(control, input, output); Reviewed-by: Nuno Das Neves <nunodasneves@xxxxxxxxxxxxxxxxxxx>