On Fri, Jul 26, 2024 at 03:59:07PM -0700, Roman Kisel wrote: > To run in the VTL mode, Hyper-V drivers have to know what > VTL the system boots in, and the arm64/hyperv code does not > update the variable that stores the value. > > Update the variable to enable the Hyper-V drivers to boot > in the VTL mode and print the VTL the code runs in. > > Signed-off-by: Roman Kisel <romank@xxxxxxxxxxxxxxxxxxx> > --- > arch/arm64/hyperv/Makefile | 1 + > arch/arm64/hyperv/hv_vtl.c | 13 +++++++++++++ > arch/arm64/hyperv/mshyperv.c | 4 ++++ > arch/arm64/include/asm/mshyperv.h | 7 +++++++ > 4 files changed, 25 insertions(+) > create mode 100644 arch/arm64/hyperv/hv_vtl.c > > diff --git a/arch/arm64/hyperv/Makefile b/arch/arm64/hyperv/Makefile > index 87c31c001da9..9701a837a6e1 100644 > --- a/arch/arm64/hyperv/Makefile > +++ b/arch/arm64/hyperv/Makefile > @@ -1,2 +1,3 @@ > # SPDX-License-Identifier: GPL-2.0 > obj-y := hv_core.o mshyperv.o > +obj-$(CONFIG_HYPERV_VTL_MODE) += hv_vtl.o > diff --git a/arch/arm64/hyperv/hv_vtl.c b/arch/arm64/hyperv/hv_vtl.c > new file mode 100644 > index 000000000000..38642b7b6be0 > --- /dev/null > +++ b/arch/arm64/hyperv/hv_vtl.c > @@ -0,0 +1,13 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (C) 2024, Microsoft, Inc. > + * > + * Author : Roman Kisel <romank@xxxxxxxxxxxxxxxxxxx> > + */ > + > +#include <asm/mshyperv.h> > + > +void __init hv_vtl_init_platform(void) > +{ > + pr_info("Linux runs in Hyper-V Virtual Trust Level\n"); > +} > diff --git a/arch/arm64/hyperv/mshyperv.c b/arch/arm64/hyperv/mshyperv.c > index 341f98312667..8fd04d6e4800 100644 > --- a/arch/arm64/hyperv/mshyperv.c > +++ b/arch/arm64/hyperv/mshyperv.c > @@ -98,6 +98,10 @@ static int __init hyperv_init(void) > return ret; > } > > + /* Find the VTL */ > + ms_hyperv.vtl = get_vtl(); > + hv_vtl_init_platform(); > + > ms_hyperv_late_init(); > > hyperv_initialized = true; > diff --git a/arch/arm64/include/asm/mshyperv.h b/arch/arm64/include/asm/mshyperv.h > index a7a3586f7cb1..63d6bb6998fc 100644 > --- a/arch/arm64/include/asm/mshyperv.h > +++ b/arch/arm64/include/asm/mshyperv.h > @@ -49,6 +49,13 @@ static inline u64 hv_get_msr(unsigned int reg) > ARM_SMCCC_OWNER_VENDOR_HYP, \ > HV_SMCCC_FUNC_NUMBER) > > +#ifdef CONFIG_HYPERV_VTL_MODE > +void __init hv_vtl_init_platform(void); > +int __init hv_vtl_early_init(void); > +#else > +static inline void __init hv_vtl_init_platform(void) {} > +#endif > + These functions are defined in x86 header as well. We can move it to generic header. - Saurabh