On Tue, 17 Aug 2021 09:11:22 +0100,
Fuad Tabba <tabba@xxxxxxxxxx> wrote:
>
> Fix the places in KVM that treat MDCR_EL2 as a 32-bit register.
> More recent features (e.g., FEAT_SPEv1p2) use bits above 31.
>
> No functional change intended.
>
> Acked-by: Will Deacon <will@xxxxxxxxxx>
> Signed-off-by: Fuad Tabba <tabba@xxxxxxxxxx>
> ---
> arch/arm64/include/asm/kvm_arm.h | 20 ++++++++++----------
> arch/arm64/include/asm/kvm_asm.h | 2 +-
> arch/arm64/include/asm/kvm_host.h | 2 +-
> arch/arm64/kvm/debug.c | 2 +-
> arch/arm64/kvm/hyp/nvhe/debug-sr.c | 2 +-
> arch/arm64/kvm/hyp/vhe/debug-sr.c | 2 +-
> 6 files changed, 15 insertions(+), 15 deletions(-)
>
> diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h
> index d436831dd706..6a523ec83415 100644
> --- a/arch/arm64/include/asm/kvm_arm.h
> +++ b/arch/arm64/include/asm/kvm_arm.h
> @@ -281,18 +281,18 @@
> /* Hyp Debug Configuration Register bits */
> #define MDCR_EL2_E2TB_MASK (UL(0x3))
> #define MDCR_EL2_E2TB_SHIFT (UL(24))
> -#define MDCR_EL2_TTRF (1 << 19)
> -#define MDCR_EL2_TPMS (1 << 14)
> +#define MDCR_EL2_TTRF (UL(1) << 19)
> +#define MDCR_EL2_TPMS (UL(1) << 14)
> #define MDCR_EL2_E2PB_MASK (UL(0x3))
> #define MDCR_EL2_E2PB_SHIFT (UL(12))
> -#define MDCR_EL2_TDRA (1 << 11)
> -#define MDCR_EL2_TDOSA (1 << 10)
> -#define MDCR_EL2_TDA (1 << 9)
> -#define MDCR_EL2_TDE (1 << 8)
> -#define MDCR_EL2_HPME (1 << 7)
> -#define MDCR_EL2_TPM (1 << 6)
> -#define MDCR_EL2_TPMCR (1 << 5)
> -#define MDCR_EL2_HPMN_MASK (0x1F)
> +#define MDCR_EL2_TDRA (UL(1) << 11)
> +#define MDCR_EL2_TDOSA (UL(1) << 10)
> +#define MDCR_EL2_TDA (UL(1) << 9)
> +#define MDCR_EL2_TDE (UL(1) << 8)
> +#define MDCR_EL2_HPME (UL(1) << 7)
> +#define MDCR_EL2_TPM (UL(1) << 6)
> +#define MDCR_EL2_TPMCR (UL(1) << 5)
> +#define MDCR_EL2_HPMN_MASK (UL(0x1F))
>
> /* For compatibility with fault code shared with 32-bit */
> #define FSC_FAULT ESR_ELx_FSC_FAULT
> diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
> index 9f0bf2109be7..63ead9060ab5 100644
> --- a/arch/arm64/include/asm/kvm_asm.h
> +++ b/arch/arm64/include/asm/kvm_asm.h
> @@ -210,7 +210,7 @@ extern u64 __vgic_v3_read_vmcr(void);
> extern void __vgic_v3_write_vmcr(u32 vmcr);
> extern void __vgic_v3_init_lrs(void);
>
> -extern u32 __kvm_get_mdcr_el2(void);
> +extern u64 __kvm_get_mdcr_el2(void);
>
> #define __KVM_EXTABLE(from, to) \
> " .pushsection __kvm_ex_table, \"a\"\n" \
> diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
> index 347781f99b6a..4d2d974c1522 100644
> --- a/arch/arm64/include/asm/kvm_host.h
> +++ b/arch/arm64/include/asm/kvm_host.h
> @@ -289,7 +289,7 @@ struct kvm_vcpu_arch {
>
> /* HYP configuration */
> u64 hcr_el2;
> - u32 mdcr_el2;
> + u64 mdcr_el2;
This breaks an existing trace in debug.c::kvm_arm_setup_mdcr_el2():
trace_kvm_arm_set_dreg32("MDCR_EL2", vcpu->arch.mdcr_el2);
which expects a 32bit value. I guess we could add an equivalent 64bit
version, or silently upgrade the tracepoint to take a 64bit value.
None of them are good solutions, but hey, something has to give...
Thanks,
M.
--
Without deviation from the norm, progress is not possible.
